HK1161064A - Tissue modification devices and methods of using the same - Google Patents

Description

Tissue modification devices and methods of use

Cross Reference to Related Applications

According to 35u.s.c § 119(e), the present application claims priority from U.S. provisional patent application serial No.61/082,774 filed on 7/22/2008 and U.S. application No.12/422,176 filed on 10/4/2009; the contents of these two U.S. patent applications are incorporated herein by reference.

Background

Traditional surgery, whether therapeutic or diagnostic, can cause significant trauma to intermediate tissues (intervening tissue) due to pathologies within the body. These procedures often require long incisions, extensive muscle stripping, prolonged tissue retraction, denervation of the tissue, and interruption of blood supply. These procedures can require several hours of surgical time, and several weeks of post-operative recovery time due to damage to tissue during the procedure. In some cases, these invasive procedures result in permanent scarring, as well as pain that may be more severe than the pain that results from performing the surgical procedure.

Because of the need for minimal dissection of tissue, such as muscle tissue, the development of percutaneous surgery has made major improvements in reducing recovery time and post-operative pain. For example, minimally invasive surgical techniques are desirable for spinal and neurosurgical applications because of the need to access internal body locations and the risk of injury to critical intervening tissues. Although the development of minimally invasive surgery is a step in the right direction, there is a need for further development of minimally invasive surgical instruments and methods.

Disclosure of Invention

A tissue modification device is provided. Aspects of the device include an elongate member having a proximal end and a distal end. The distal end of the elongate member is dimensioned to pass through the minimally invasive body opening and includes a distal integrated visualization sensor and tissue modifier. In some examples, the device further comprises an integrated articulation mechanism that provides steering capability for at least one of the visualization sensor, the tissue modifier, and the distal end of the elongate member. Methods for altering internal target tissue of a subject using a tissue altering device are also provided.

Drawings

Fig. 1A and 1B provide two different views of a disposable tissue modification device according to embodiments of the present invention.

Fig. 2A-2C provide cross-sectional views of the distal end of devices according to some embodiments of the present invention.

Figures 3A through 3E provide cross-sectional views of the distal end of devices according to some embodiments of the present invention.

FIG. 4 provides an alternative view of the distal end of a device according to an embodiment of the present invention, wherein the device is shown approaching the nucleus pulposus of an intervertebral disc.

FIG. 5 provides an alternative view of the distal end of a device according to an embodiment of the present invention, wherein the device is shown approaching the nucleus pulposus of an intervertebral disc.

Fig. 6A through 6E provide various views of the distal end of a device according to one embodiment of the present invention.

Fig. 7 provides a cut-away view of the device shown in fig. 1A and 1B.

Fig. 8 provides an illustration of a system according to an embodiment of the present invention, wherein the system comprises a disposable tissue modifier device and an extracorporeal control unit.

FIG. 9 provides a block diagram illustrating the architecture of a system and how the system interacts with a user, according to one embodiment of the invention.

FIG. 10 illustrates a CMOS (complementary metal oxide semiconductor) visualization subsystem that may be incorporated into a tissue modification system according to an embodiment of the present invention.

Fig. 11 provides a block flow diagram of a stereoscopic image module according to an embodiment.

Fig. 12A provides a single development sensor that moves between two different positions to sequentially obtain image data according to an embodiment. Fig. 12B provides slightly offset development positions of two different development sensors according to an embodiment.

FIG. 13 provides a functional block diagram of a portion of a system including a video processor module, according to one embodiment.

Fig. 14 provides a flowchart of an image processing module according to an embodiment.

FIG. 15 provides a schematic diagram of the operational architecture of a processor configured to generate video from image data obtained under white light and/or near infrared light in accordance with an embodiment of the present invention.

FIG. 16 provides a cross-sectional view of a distal end of an elongate member and an access device of a minimally invasive tissue modification device according to one embodiment.

Figure 17 provides different views of an access device according to an embodiment.

FIG. 18 provides a device with two cameras positioned within the same cross-section at the distal end of the device according to an embodiment.

Fig. 19 provides a number of views of an electric motor linear actuator that may be present in the device of the present invention to provide linear translation for RF (radio frequency) electrodes, according to an embodiment.

Detailed Description

A tissue modification device is provided. Aspects of the device include an elongate member having a proximal end and a distal end. The distal end of the elongate member is dimensioned to pass through the minimally invasive body opening and includes a distally integrated visualization sensor and tissue modifier. In some examples, the device further comprises an integrated articulation mechanism that provides steering capability for at least one of the visualization sensor, the tissue modifier, and the distal end of the elongate member. A method of altering an internal target tissue of a subject using a tissue modification device is also provided.

Before the present invention is described in greater detail, it is to be understood that this invention is not limited to particular embodiments described, as such may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting, since the scope of the present invention will be limited only by the appended claims.

Where a range of values is provided, it is understood that each intervening value, to the tenth of the unit of the lower limit unless the context clearly dictates otherwise, between the upper and lower limit of that range and any other stated or intervening value in that stated range is encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included in the smaller ranges and are also encompassed within the invention, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of these limits, ranges excluding either or both of these included limits are also included in the invention.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although any methods and materials similar or equivalent to those described herein can also be used in the practice or testing of the present invention, representative exemplary methods and materials are now described.

All publications and patents cited in this specification are herein incorporated by reference as if each individual publication or patent were specifically and individually indicated to be incorporated by reference and were incorporated by reference to disclose and describe the methods and/or materials in connection with which the publications were cited. The citation of any publication is for its disclosure prior to the filing date and should not be construed as an admission that the present invention is not entitled to antedate such publication by virtue of prior invention. Further, the dates of publication provided may be different from the dates of actual publication that may need to be independently confirmed.

It is noted that, as used herein and in the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. It is further noted that the claims may be drafted to exclude any optional element. Also, this statement is intended to serve as antecedent basis for use of such exclusive terminology as "solely," "only," and the like in connection with the recitation of claim elements, or use of a "negative" limitation.

Each of the individual embodiments described and illustrated herein has discrete components and features that can be readily separated from or combined with the features of any of the other several embodiments without departing from the scope or spirit of the present invention, as will be apparent to those skilled in the art upon studying this disclosure. Any recited methods may be performed in the order of the referenced examples, or in any other order that is logically possible.

In further describing aspects of the present invention, various aspects of embodiments of the subject tissue modification devices are first described in greater detail. Next, embodiments of methods of altering target tissue within a subject using the subject tissue altering devices will be described in greater detail.

Tissue modification device

Aspects of the present invention include tissue modification devices that may be used to modify an internal target tissue site, such as a spinal location near or within an intervertebral disc (IVD). As outlined above, the tissue modification devices are sized such that at least the distal ends of these devices can pass through the minimally invasive body opening. Also, at least the distal end of these devices may be passed through a small bore incision (minor incision) into an internal target site of a patient, such as a spinal site located near or within an intervertebral disc, such as a small bore incision having a size smaller than the size of an incision used with an access device having an outer diameter of 20mm or less, such as less than 75% of the size of such incision, such as less than 50% of the size of such incision, or less. In some examples, at least the distal end of the elongate member is sized to pass through Cambin's triangle. The Kambin's triangle, also known as Panbin's triangle, is an anatomical spinal structure defined by the exiting and passing nerve roots and the intervertebral disc. The exiting nerve root is the nerve root that directs the spinal canal cephalad (superior) to the intervertebral disc, and the passing nerve root is the nerve root that directs the spinal canal caudally (inferior) to the intervertebral disc. Where the distal end of the elongate member is dimensioned to pass through Kambin's triangle, at least the distal end of the device has a longest cross-sectional dimension of 10mm or less, such as 8mm or less and including 7mm or less. In some examples, the elongate member has an outer diameter that is 7.5mm or less, such as 7.0mm or less, including 6.7mm or less, such as 6.6mm or less, 6.5mm or less, 6.0mm or less, 5.5mm or less, 5.0mm or less.

As outlined above, the tissue modification device of the present invention comprises an elongate member. Because such a component of the device is elongated, such a component has a length that is 1.5 times or more, such as 2 times or more, including 5 times or even 10 times or more, of the width of such a component, such as 20 times or more, 30 times or more, of the width of such a component. The length of the elongate member may vary, in some examples ranging from 5cm to 20cm, such as 7.5cm to 15cm and including 10 to 12 cm. The elongated member may have the same external cross-sectional dimension (e.g., diameter) along its entire length. Alternatively, the cross-sectional diameter may vary along the length of the elongated member.

The elongate member of the subject tissue modification devices has a proximal end and a distal end. As used herein, the term "proximal" refers to the end of the elongate member that is closer to a user (e.g., a physician operating the device in a tissue modification procedure), and as used herein, the term "distal" refers to the end of the elongate member that is closer to the target internal tissue of a subject during use. In some examples, the elongate member is a structure that is sufficiently rigid to allow the distal end to be pushed through tissue when a sufficiently large force is applied to the proximal end of the elongate member. Also, in these embodiments, the elongate member is not pliable or soft, at least not to a significant extent.

Depending on the particular device embodiment, the elongate member may or may not include one or more lumens extending at least partially along the length of the elongate member. When present, the lumen may vary in diameter and may be used for a variety of different purposes, such as irrigation, aspiration, electrical isolation (e.g., of an electrically conductive member such as a lead), e.g., as a mechanical guide, etc., as described in more detail below. When present, the lumens may have a longest cross-section, which in some examples varies in a range from 0.5 to 5.0mm, such as a range of 1.0 to 4.5mm, including a range of 1.0 to 4.0 mm. The cavities can have any convenient cross-section as desired, including but not limited to circular, square, rectangular, triangular, semi-circular, trapezoidal, irregular, etc. These lumens may be provided for a variety of different functions, including as irrigation lumens and/or suction lumens, as described in more detail below.

As outlined above, the device comprises a distal-end integrated visualization sensor and a distal-end integrated tissue modifier. Since the visualization sensor is integrated at the distal end of the device, the visualization sensor cannot be removed from the rest of the device without significantly compromising the structure and function of the device. Thus, the device of the present invention differs from devices that include a "working channel" in which a separate autonomous device, such as a tissue modifier, passes through the working channel. In contrast to these devices, since the visualization sensor of the device of the present invention is integrated at the distal end, it is not such a device as follows: a device which is present only in the working channel of the elongated member and which can be removed from the working channel of such elongated member independently of the elongated member without structurally damaging the elongated member in any way. The visualization sensor may be integrated with the distal end of the elongated member in a number of different configurations. The integrated configuration includes a configuration in which the development sensor is fixed with respect to the distal end of the long member, and a configuration in which the development sensor is movable to some extent with respect to the distal end of the long member. Movement of the visualization sensor relative to the distal end of the elongate member may also be provided, but the visualization sensor is stationary relative to movement of another component at the distal end, such as a distal integrated tissue modifier. The specific configuration of interest is further described below in conjunction with the accompanying drawings. In some examples, the device may include two or more visualization sensors integrated at the distal end of the elongate member, such as described in more detail below.

The development sensor comprises a miniature imaging sensor having a cross-sectional area that is small enough for its intended use, but retains a sufficiently high matrix resolution. For example, some of the development sensors of the present invention have a cross-sectional area (i.e., x-y dimensions, also known as the packaged chip size) of 2mm by 2mm or less, such as 1.8mm by 1.8mm or less, but also have a matrix resolution of 400 x 400 or greater, such as 640 x 480 or greater. In some examples, the imaging sensor has a sensitivity of 500mV/Lux-Sec or greater, such as 700mV/Lux-Sec or greater, including 1000mV/Lux-Sec or greater, wherein in some examples, the sensitivity of the sensor is 2000mV/Lux-Sec or greater, such as 3000mV/Lux-Sec or greater. The imaging sensor is of the type that includes a light sensitive component, such as an array of light sensitive elements that convert light into electrons, coupled to an integrated circuit. The integrated circuit may be configured to obtain and integrate signals from the photosensitive array and output image data, which may in turn be transmitted to an extracorporeal device configured to receive and display data to a user. The image sensors of these embodiments may be considered as integrated circuit image sensors. The integrated circuit components of these sensors may include a variety of different types of functionality, including but not limited to: image signal processing, a memory, and a data transmission circuit for transmitting data from the development sensor to a location outside the body. The miniature imaging sensor may further comprise a lens component comprised of one or more lenses positioned relative to the light-sensitive component to focus an image on the light-sensitive component. One or more lenses may be present within the housing, if desired. Specific types of the micro imaging sensor include a Complementary Metal Oxide Semiconductor (CMOS) sensor and a Charge Coupled Device (CCD) sensor. The sensor may have any convenient configuration, including circular, square, rectangular, and the like. The visualization sensor can have a longest cross-sectional dimension that varies depending on the particular embodiment, where in some embodiments the longest cross-sectional dimension (e.g., diameter) is 4.0mm or less, such as 3.5mm or less, including 3.0mm or less, such as 2.5mm or less, including 2.0mm or less, including 1.5mm or less, including 1.0mm or less.

The imaging sensor may be a front-or back-illuminated sensor and have a sufficiently small size while retaining sufficient functionality to be integrated at the distal end of the elongated member of the inventive device. Aspects of these sensors are further described in one or more of the following U.S. patents, the contents of which are incorporated herein by reference: 7,388,242, respectively; 7,368,772, respectively; 7,355,228, respectively; 7,345,330, respectively; 7,344,910, respectively; 7,268,335, respectively; 7,209,601, respectively; 7,196,314, respectively; 7,193,198, respectively; 7,161,130, respectively; and 7,154,137.

When the visualization sensor is a distal end integrated visualization sensor, it is located at or near the distal end of the elongated member. Thus, it is located at or closer to the distal end by 3mm, such as at or closer to the distal end by 2mm, including at or closer to the distal end by 1 mm. In some examples, the visualization sensor is located at a distal end of the elongated member. The development sensor may provide front viewing and/or side viewing as desired. Thus, the development sensor may be configured to provide image data viewed from the distal end of the long member in the forward direction. Alternatively, the development sensor may be configured to provide image data viewed from the side of the long member. In still other embodiments, the development sensor may be configured to provide image data as viewed from the front and sides, such as where the image sensor faces at an angle of less than 90 ° relative to the longitudinal axis of the elongated member, such as shown in fig. 6A-6C, described in more detail below.

Since the visualization sensor is a remote integrated visualization sensor, the visualization sensor also includes functionality for transmitting image data to an extracorporeal device, such as an image display device. In some examples, there may be a signal cable (or other type of signal transmission element) to connect the image sensor at the distal end to a device at the proximal end of the elongate member, for example in the form of one or more wires extending along the length of the elongate member from the distal end to the proximal end. Alternatively, a wireless communication protocol may be employed, for example, where the imaging sensor is operatively coupled to a wireless data transmitter, the wireless data transmitter may be positioned at the distal end of the elongate member (including integrated into the visualization sensor, at some location along the elongate member or at the proximal end of the device, such as at a location at the proximal end of the elongate member or coupled to a handle of the device).

In certain embodiments, an image sensor configuration described in co-pending U.S. patent application serial No.12/269,770 (the contents of which are incorporated herein by reference) is present in the device. In these embodiments, the device may include a visualization sensor configuration at least during use, the visualization sensor configuration characterized by having two or more visualization sensors located at a distal end of the device. The two or more visualization sensors may be integrated with the distal end of the device altogether, or distributed between the device and another device, such as a separate access device, or located only on the access device. Accordingly, embodiments may include those systems in which two or more visualization sensors are located at the distal end of the elongated member. Embodiments may also include those wherein one visualization sensor is located at the distal end of the elongated member and another visualization element is located proximate the distal end of the device. Further, embodiments may include such systems wherein two or more visualization elements are located proximate the distal end of the device. It should be noted that although these particular visualization sensor configurations are described primarily with respect to devices that include a distal integrated tissue modification device, the present invention also includes devices that include such visualization sensor configurations, but may not include an integrated distal tissue modification device, for example, as described in U.S. patent application serial No.12/269,770 (the contents of which are incorporated herein by reference).

Where desired, the device may include one or more illumination elements configured to illuminate the target tissue site such that the site may be displayed with a visualization sensor such as described above. Many different types of light sources may be used as the illumination element, as long as they are sized such that they can be located at the distal end of the elongated member. The light sources may be integrated with a given component (e.g., an elongated member) such that they are configured relative to the component such that the light source elements cannot be removed from the remainder of the component without significantly compromising the component structure. Also, the integrated lighting elements of these embodiments are not readily removable from the remainder of the component such that the lighting elements and the remainder of the component form an interrelated whole. The light source may be a light emitting diode configured to emit light of a desired wavelength range, or an optical transmission element, such as an optical fiber, configured to transmit light of the desired wavelength range from a location other than the distal end of the elongate member, e.g., at the proximal end of the elongate member, to the distal end of the elongate member. As with the image sensor, the light source may include a conductive element, such as a wire or fiber, that extends along the length of the elongated member to provide power and control to the light source from a location external to the body, such as an extracorporeal control device. In certain embodiments, the light source may be configured to wirelessly communicate with an extracorporeal control device. Where desired, the light source may include a diffusing element that provides uniform illumination of the target tissue site. Any convenient diffusing element may be used, including but not limited to translucent covers or layers (made of any convenient translucent material) through which light from the light source is transmitted and thus diffused.

The device of the invention may comprise two or more lighting elements, if desired. In those embodiments of the invention where the system comprises two or more lighting elements, the lighting elements may emit light of the same wavelength, or they may be light sources of different spectral characteristics, wherein by "different spectral characteristics" it is meant that the light sources emit light of wavelengths that do not substantially overlap, e.g. white light and infrared light. "white light" light sources are those configured to illuminate a tissue site with white light, i.e., electromagnetic radiation having a wavelength visible to the human eye (approximately 400-700nm), or up to 380-750 nm. The near infrared light source is a light source configured to illuminate the tissue site with near infrared light, i.e., near infrared radiation having a wavelength between about 700nm and 1100 nm.

In certain embodiments where there are two or more different illumination elements, there may also be a controller configured to alternately illuminate a target tissue, such as an intervertebral disc or portion of an intervertebral disc, with a white light source and a near infrared light source. By "alternating", it is meant that there is a transition somewhere from illumination with a white light source and illumination with a near infrared light source. In these embodiments, the controller may also be configured to cause the image sensor to obtain one or more images, such as photographs or video, under various types of illumination, for example, white light image data and infrared image data. The term "image data" refers to data that may be used by a processor to produce some type of human-visible image, such as a photographic image or video, on a suitable display, such as a monitor.

In certain embodiments, the processor is configured to provide a multispectral image to the user, the multispectral image being generated from image data obtained under white light illumination and near infrared illumination. Multispectral images may be generated to provide the user with: many different types of information are not available to a user using image data obtained under a single illumination spectrum. For example, multispectral images may be generated to provide a user with three-dimensional effects that present depth information to the user during use, such as tissue dissection, lavage, and aspiration procedures.

In some embodiments, the processor may be configured to generate video from image data obtained under white light, or under near infrared light, or a combination of both, i.e., generate multi-spectral or combined video. For example, if the target tissue site is relatively fluid-free, the user may desire to view the site under white light illumination. Alternatively, where the target tissue site is filled with fluid, the user may desire to view the site under near infrared illumination.

In certain embodiments, a lighting configuration consisting of two or more lighting elements described in co-pending U.S. patent application serial nos. 12/269,770 and 12/269,772 (the contents of which are incorporated herein by reference) is present in the device. It should be noted that although embodiments of the present invention having two or more light sources are described herein primarily with respect to minimally invasive tissue modification devices also having an integrated tissue modifier at the tip, embodiments of the present invention having two or more distal illumination elements but lacking a tip tissue modifier and/or visualization sensor (e.g., as described in U.S. patent application serial nos. 12/269,770 and 12/269,772, the disclosures of which are incorporated herein by reference) are also encompassed within the scope of the present invention. Thus, embodiments may include those systems in which two or more illumination elements are located at the distal end of the elongate member. Embodiments may also include those systems in which one illumination element is located at the distal end of the elongated member and another illumination element is located at the distal end of another device, such as proximal to the device. Further, embodiments may include those systems in which two or more illumination elements are located at a distal end of another device, such as a proximal device.

In addition to the distal integrated visualization sensor, the device of embodiments of the present invention also includes an integrated distal tissue modifier. Because the tissue modifier is integrated at the distal end of the device, it cannot be completely removed from the rest of the device without significantly compromising the structure and function of the device. Although the tissue modifier cannot be completely removed from the remainder of the device without significantly compromising the structure and function of the device, the components of the tissue modifier may be removable and replaceable. For example, the RF electrode tissue modifier may be configured such that the lead member of the tissue modifier may be replaceable while the remainder of the tissue device is not. Thus, the device of the present invention differs from devices that include a "working channel" through which a separate autonomous tissue modifier device, such as an autonomous RF electrode device, passes. In contrast to these devices, since the tissue modifier of the device of the invention is integrated at the distal end, it is not the following: means which are independent with respect to the elongated member, are present only in the working channel of the elongated member and can be removed from the working channel of such elongated member without damaging the elongated member in any way structurally. The tissue modifier may be integrated with the distal end of the elongate member by various configurations. Integrated configurations include configurations in which the tissue modifier is fixed relative to the distal end of the elongate member, and configurations in which the tissue modifier is movable to some extent relative to the distal end of the elongate member may be used in the devices of the invention. The specific configurations of interest are further described below in conjunction with the accompanying figures. Because the tissue modifier is a distally integrated tissue modifier, it is located at or near the distal end of the elongate member. Thus, the tissue modifier is located 10mm or less from the distal end, for example 5mm or less from the distal end, including 2mm or less from the distal end. In some examples, the tissue modifier is located at the distal end of the elongate member.

A tissue modifier is a component that interacts with tissue in some way to modify the tissue in a desired way. The term "altering" is used broadly to mean changing in some way, including cutting tissue, resecting tissue, delivering an agent to tissue, freezing tissue, and the like. Thus, as with tissue modifiers, tissue cutters, tissue resectors, tissue freezing/heating elements, reagent delivery devices, and the like are also of interest. The tissue cutters include, but are not limited to: blades, liquid jet devices, lasers, etc. Including, but not limited to, ablation devices such as devices for delivering ultrasonic energy (such as when used for ultrasonic ablation), plasma energy, Radio Frequency (RF) energy, microwave energy, and the like. The energy transmission devices include, but are not limited to: means for regulating the temperature of the tissue, such as freezing or heating means, etc. In some embodiments, the tissue modifier is not a tissue modifier that effects tissue modification by grasping, clipping, or grasping tissue, such as may be achieved by a device that traps tissue between opposing surfaces (e.g., similar to a caliper-like device). In these embodiments, the tissue modification device is not an element configured to tear tissue apart, for example, by applying mechanical force such as by trapping the tissue between opposing surfaces. In some embodiments, the tissue modification includes effects other than removal by only low pressure irrigation or aspiration, such as some other effects performed on the tissue in addition to low pressure irrigation and/or aspiration. In some embodiments, the tissue modifier is distinct from the probe element, or device configured to move tissue without any change to the tissue other than simple movement or repositioning, such as by retraction, atraumatic motion, or the like.

In some examples, the tissue modifier includes at least one electrode. For example, the tissue modifier can comprise an RF energy tissue modifier comprising at least one electrode and can be configured in a number of different ways depending on the desired configuration of the RF circuit. The RF circuit may be formed substantially completely at the target tissue site of interest (bipolar device) or by using a second electrode attached to another part of the patient's body (monopolar device). In either case, controlled delivery of RF energy is achieved. Aspects of the subject tissue modification devices include a Radio Frequency (RF) electrode at a distal end of an elongate member. RF electrodes are devices for transmitting radio frequency energy such as ultrasound, microwaves, and the like. In some examples, the RF electrode is an electrical conductor for delivering RF energy to a particular location, such as desired target tissue. For example, in some cases, the RF electrode may be an RF ablation electrode. The RF electrode of the subject tissue modification devices may include a conductor, such as a metal wire, and may be dimensioned to approximate the intervertebral disc space. The RF electrode can be shaped in a number of different forms, such as circular, square, rectangular, oval, and the like. The size of such electrodes can vary, with the RF electrode having a longest cross-sectional dimension in some embodiments of 7mm or less, 6mm or less, 5mm or less, 4mm or less, 3mm or less, or even 2mm or less, as desired. Where the electrodes comprise wires, the wire diameter in such embodiments may be 180 μm, such as 150 μm or less, such as 130 μm or less, such as 100 μm or less, such as 80 μm or less. A number of different RF electrode configurations suitable for use in tissue modification include, but are not limited to, those described in the following U.S. patents: no.7,449,019; no.7,137,981; no.6,997,941; no.6,837,887; no.6,241,727; no.6,112,123; no.6,607,529; no.5,334,183. The RF electrode system or components thereof may be adapted for use in the device of the present invention (when the guidance provided in connection with the description of the invention is incorporated herein by reference), and as such, the disclosure of the RF electrode configurations in these patents is incorporated herein by reference. The specific construction of the RF electrode is further described below in conjunction with the figures.

In some examples, the tissue modifier is supplied with current from an RF energy source. The voltage signal that drives current to the tissue modifier may be defined as a sinusoidal waveform, a square waveform, a sawtooth waveform, a triangular waveform, a pulse waveform, a non-standard waveform, a complex waveform, an irregular waveform, or the like, having a well-defined operating frequency. For example, the operating frequency may range from 1KHz to 50MHz, such as from 100KHz to 25MHz, and including from 250KHz to 10 MHz. In some embodiments, the RF voltage signal is a sine wave having an operating frequency of 460 KHz. In addition, the operating frequency of the tissue modifier may be modulated by modulating the waveform. By "modulated", it is meant that the amplitude is reduced by a second waveform, such as a periodic signal waveform. The modulation waveform may be definable with a well-defined modulation frequency, such as a sinusoidal waveform, a square waveform, a sawtooth waveform, a triangular waveform, a pulse waveform, a non-standard waveform, a complex waveform, or an irregular waveform, among others. For example, the modulation frequency may range from 1Hz to 10KHz, such as from 1Hz to 500Hz, and include from 10Hz to 100 Hz. In some embodiments, the modulation waveform is a square wave having a modulation frequency of 70 Hz.

In some embodiments, the RF tuner is included as part of the RF energy source. An RF tuner includes basic electrical components (e.g., capacitors and inductors) that function to adjust the output impedance of the RF energy source. The term "adjust" is intended herein to have a broad interpretation including affecting the electrical response to achieve maximum power delivery, affecting the electrical response to achieve a constant power (or voltage) level under different load conditions, affecting the electrical response to achieve different power (or voltage) levels under different load conditions. Furthermore, the elements of the RF tuner are selectable such that the output impedance is dynamically adjusted, meaning that the RF tuner is self-adjusting according to the load impedance encountered at the electrode tip. For example, the elements may be selected such that when the electrode is placed in saline solution (saline solution grounded to the return electrode), the electrode has sufficient voltage to form a plasma corona, but then when the electrode contacts tissue (tissue also grounded to the return electrode, e.g., through saline solution), the voltage level may be self-adjusted to a lower threshold, thus dynamically maintaining a plasma corona at the electrode tip while minimizing power delivered to the tissue and thermal shock to surrounding tissue. The presence of an RF tuner may provide a number of advantages. For example, delivering RF energy to target tissue through the distal tip of the electrode is challenging because RF energy undergoes attenuation and reflection along the conductive path length from the RF energy source to the electrode tip, which can lead to insertion loss. Including an RF tuner such as described above may help minimize and control insertion loss.

The devices of the present invention may include a linear mechanical actuator for linearly translating a distal element of the device, such as a tissue modifier (e.g., an RF electrode), relative to the distal end of the elongate member. By "linearly translating" is meant moving the tissue modifier along a substantially linear path. As used herein, the term "linear" also includes movement of the tissue modifier along a non-linear (i.e., curvilinear) path. For example, if the electrode encounters tissue of different densities (e.g., cartilage, bone, etc.), or the tissue structure through which the electrode is passing is not linear, etc., the path of motion of the tissue modifier may be skewed from a substantially linear path.

When actuated by a linear mechanical actuator, the tissue modifier is periodically moved from a "neutral" position along its axial extension to a position moved distally or proximally from the neutral position, and the maximum displacement moved from the neutral position corresponds to the vibration amplitude. Thus, the linear mechanical actuator actuates the tissue modifier by a distance equal to twice the amplitude of the vibration and covering the distance from the distal limit position to the proximal limit position. In some embodiments, the tissue modifier may extend 0.1mm or more, such as 0.5mm or more, including 1mm or more, such as 2mm or more, such as 5mm or more, from the elongate member distal end by a linear mechanical actuator. This back and forth movement of the tissue modifier relative to the distal end of the elongate member by the linear mechanical actuator is described herein in terms of a linear translation frequency. Note that the distal limit positions and the proximal limit positions described above refer to those positions reached by the linear mechanical actuator alone. In some embodiments, the linear mechanical actuator may be the only means for translating the electrode. In other embodiments, such as described in more detail below, the linear mechanical actuator may provide a vibration amplitude that is superimposed on another independent control that controls the translation of the electrodes, the other independent control moving the electrodes over a distance significantly greater than the vibration amplitude, such as 10mm or more, such as 20mm or more, including 30mm or more, such as 40mm or more. In this case, the tissue modifier may extend beyond a range defined by the distal limit position and the proximal limit position defined by the linear mechanical actuator described above. For example, a manual control (e.g., a thumbwheel or similar structure) may be provided on the device that allows a user to move the tissue modifier relative to the distal end in a motion other than that provided by the linear mechanical actuator.

Accordingly, the device of the present invention may include a linear mechanical actuator configured to linearly translate the tissue modifier relative to the distal end at a linear translation frequency. The linear mechanical actuator may be any of a variety of actuators that are convenient for use in the subject devices for linearly translating the tissue modifier relative to the distal end of the elongate member. For example, the linear mechanical actuator may be a Voice Coil Motor (VCM), a solenoid, a pneumatic actuator, an electric motor, or the like. A linear mechanical actuator is operatively coupled to the tissue modifier. By "operatively coupled" it is meant that the linear mechanical actuator is connected to the tissue modifier such that linear motion of the actuator is transferred to the tissue modifier, thereby extending the tissue modifier from or retracting the tissue modifier towards the distal end of the elongated member, depending on the direction of motion of the linear actuator.

When present, the linear actuator is for linearly translating the tissue modifier at a linear translation frequency. In some examples, the linear translation frequency is 10Hz or greater, such as 25Hz or greater, including 50Hz or greater, such as 100Hz or greater. In some embodiments, the linear translation frequency is 70 Hz. In some examples, translation of the tissue modifier between the distal limit position and the proximal limit position occurs at a predetermined linear translation frequency, while in other embodiments, the linear translation frequency may not be predetermined. The translation frequency (whether predetermined or not) may depend on various factors such as, but not limited to, the type of tissue being altered, the total amount of tissue being altered, the location of the tissue, the proximity of surrounding tissue, the tissue architecture, the type of procedure being performed, the nature of the linear mechanical actuator, the DC (direct current) voltage applied to the actuator, the amplitude of the AC (alternating current) voltage applied to the actuator, etc. For example, in certain embodiments, the linear translation frequency is definable as a standard waveform, such as a sinusoidal waveform. In some examples, the sinusoidal waveform is an Hz sinusoidal waveform such that the linear translation frequency ranges from 1Hz to 500Hz, such as from 1Hz to 250Hz, and includes from 10Hz to 100 Hz. In other examples, the linear translation frequency is a waveform that may be defined as non-standard, complex, or irregular, among others. For example, a linear translation frequency may be a waveform that may be defined to include a period with a varying frequency, a waveform that includes a period with a varying amplitude, a waveform that includes a period with a varying frequency and a varying amplitude, a waveform in which two or more waveforms are superimposed, and so forth.

In some embodiments, the tissue modification device is configured to synchronize the linear mechanical actuation with the modulated RF waveform. By "synchronized," it is meant that two or more events are timed to operate in a coordinated manner. For example, two or more waveforms may be timed to operate in a coordinated manner. In some embodiments, the modulation frequency is equal to the linear translation frequency and the modulation waveform is phase shifted relative to the linear translation waveform. Synchronization of these waveforms may be accomplished using a variety of different protocols and may implement one or more controllers in different forms, including hardware, software, and combinations of hardware and software. For example, a single common controller may produce two phase-shifted waveforms; alternatively, a separate controller may be provided in a master-slave configuration to generate the two phase shifted waveforms; alternatively, one controller may generate a waveform, hardware (e.g., an opto-electrical encoder, a mechanical encoder, a hall sensor, etc.) may be used to trigger a physical implementation of the waveform (e.g., mechanical rotation), and a second controller may generate a second waveform with an adjustable phase shift from the trigger signal. The phase shift of the modulation waveform relative to the linearly translated waveform may be positive (phase lead) or negative (phase lag), and may have an amplitude of 0 ° to 360 ° or more, such as 0 ° to 180 °, including 60 ° to 120 °. In some embodiments of the invention, the modulation waveform lags the linear translation waveform by 90 °.

As discussed above, the tissue modifier (e.g., RF electrode) has distal and proximal limit positions of its periodic linear translation. In some embodiments, the tissue modifier is configured to deliver RF energy to the internal target tissue at a location other than the distal limit. Thus, in these examples, the modulation waveform is synchronized with the linear translation frequency such that the tissue modifier is energized when the tissue modifier is located at a position other than the distal limit position, such as when the tissue modifier is located at or near the proximal limit position. For example, as discussed above, the modulation waveform may be phase shifted relative to the linearly translated waveform.

The periodic linear translation of the tissue modification device may provide a number of functions with a number of benefits. For example, periodic linear translation of the tissue modifier at a faster rate relative to manually controlled translation (e.g., at a frequency greater than 10 Hz) will tend to physically advance the tissue modifier into the soft tissue due to the compliance of the soft tissue, while hard tissue will resist deformation and thus will not allow the tissue modifier to physically advance the hard tissue. Thus, as the electrode hits hard tissue, the electrode will push back against the elongated body, thus creating tactile feedback to the user. In some embodiments, synchronization of the modulation waveform of the tissue modifier with the linear translation waveform of the tissue modifier provides additional benefits. For example, as the tissue modifier approaches the proximal limit, rapid withdrawal of the electrode from the hard tissue it encounters will physically separate the tissue modifier from the hard tissue by a gap. In some embodiments, the tissue modifier tip is actuated only when the tissue modifier is located at or near the proximal limit position, as described above. This has the effect of preferentially delivering tissue altering energy to soft, compliant tissue as compared to firm, hard tissue. Additionally stated, this provides tissue discrimination based on elastic modulus. In the case of spinal surgical applications requiring removal of nuclear material, such as fusion, artificial total disc replacement, and artificial partial disc replacement, synchronization of the modulation waveform with the linear translation waveform facilitates delivery of tissue altering energy to the nucleus pulposus (soft compliant tissue) while minimizing delivery of tissue altering energy to the annulus fibrosus (hard, firm tissue) of the intervertebral disc and to the endplates of the vertebral body (hard, firm tissue). In addition, the cyclic linear translation of the tissue modifier helps prevent conditions where the electrodes adhere to the tissue as the tissue is resected, resulting in increased thermal effects to surrounding tissue, ineffective or discontinuous tissue dissection, charring or otherwise modified tissue build-up on the tissue modifier tip, or combinations thereof. In addition, the cyclic linear translation of the tissue modifier helps to slice the dissected tissue into smaller pieces, thus facilitating aspiration of the dissected tissue.

In some examples, the apparatus includes one or more sensors configured to obtain linear translation data. Information about the linear translation of the RF electrode is represented by "linear translation data," where such information may include information about the direction of translation, the speed of translation, translational acceleration/negative acceleration, and the like. The sensor, when present, may be positioned at any convenient location of the elongate member, such as at the distal end or the like, so long as the sensor is positioned such that the desired linear translation data may be obtained. Any of a number of different types of sensors may be employed, including but not limited to: optical encoders, mechanical encoders, photoelectric sensors, hall effect sensors, position sensors, motion detection sensors, and the like.

Additional details regarding linear translation are provided in U.S. patent application serial No.12,467,122, the contents of which are incorporated herein by reference. It should be understood that although the linear mechanical actuator elements are described herein primarily with respect to devices including integrated distal end visualization, as shown in fig. 1, devices including distal end linear translation of any element positioned at the distal end of the device are also encompassed within the scope of the present invention.

Depending on the nature of the tissue modifier, the device will include a proximal connector for operatively connecting the device and the tissue modifier to extracorporeal components required for tissue modifier operation, such as an extracorporeal RF controller, a mechanical tissue cutter controller, a liquid jet controller, and the like.

In some embodiments, there is also an integrated articulation mechanism in the device that provides steering capability to at least one of the visualization sensor, the tissue modifier, and the distal end of the elongate member. By "steerability" is meant the ability to steer or orient the visualization sensor, tissue modifier, and distal end of the elongate member as desired during a procedure, for example, by utilizing a controller positioned at the proximal end of the device. In these embodiments, the device includes a steering mechanism (or one or more elements at the distal end of the elongate member) that enables the desired distal components to be manipulated as desired by the proximal control. Also, as used herein, the term "steering capability" refers to a structure that provides a user with a steering function, such as the ability to change direction in a desired manner, such as by moving left, right, up, or down relative to an initial direction. The steering function may be provided by a variety of different mechanisms. Examples of suitable mechanisms include, but are not limited to, one or more wires, tubes, slats, mesh, or combinations thereof made of a suitable material such as shape memory material, music wire, or the like. In some examples, the tip of the elongated member is provided with a different additional function of allowing the tip of the elongated member to rotate independently about its longitudinal axis while a substantial portion of the lever is maintained in a fixed position, as discussed in more detail below. The articulation range of the distal member of the present invention may vary, for example, from-180 to +180, such as-90 to + 90. Alternatively, the distal probe tip may articulate through a range from 0 to 360 °, such as from 0 to +180 °, including from 0 to 90 °, allowing for rotation of the entire probe about its axis such that a full range of angles are accessible on either side of the probe axis, for example, as described in more detail below. The hinge mechanism is also described in the PCT application publications published below, namely No. wo 2009029639; no. wo 2008/094444; no. wo 2008/094439 and No. wo 2008/094436; the contents of which are incorporated herein by reference. The specific hinge configuration is further described below in conjunction with the figures.

In certain embodiments, the devices of the present invention may further comprise an irrigator and aspirator configured to irrigate the internal target tissue site and/or components of the device, such as the lens of the visualization sensor. Likewise, the elongate member may also include one or more lumens extending through at least a substantial length of the device, for example, for performing a variety of different functions, as outlined above. In certain embodiments where it is desired to irrigate (i.e., wash) a target tissue site located at the distal end of the elongate member (e.g., to remove excised tissue from the site, etc.), the elongate member may include both an irrigation lumen and a suction lumen. Thus, the tissue modification device may comprise an irrigation lumen at the distal end of the elongate member and the tissue modification device may comprise a suction lumen at the distal end of the elongate member. In use, the irrigation lumen is operatively connected to a fluid source (e.g., a physiologically acceptable fluid such as saline) at the proximal end of the device, wherein the fluid source is configured to introduce fluid into the lumen at a positive pressure, e.g., a pressure in the range of from 0 to 60 pounds per square inch, such that the fluid is delivered along the irrigation lumen and out the distal end. Although the size of the irrigation lumen may vary, in certain embodiments, the longest cross-sectional dimension of the irrigation lumen ranges from 0.5mm to 5mm, such as from 0.5mm to 3mm, including from 0.5mm to 1.5 mm. During use, the aspiration lumen is operatively connected to a source of negative pressure (e.g., a vacuum source) at the proximal end of the device. Although the size of the aspiration lumen may vary, in certain embodiments, the longest cross-sectional dimension of the aspiration lumen ranges from 1mm to 7mm, such as from 1mm to 6mm, including from 1mm to 5 mm. In some embodiments, the aspirator includes a port having a cross-sectional area that is 33% or more, such as 50% or more, including 66% or more, of the cross-sectional area of the distal end of the elongate member. In some examples, the negative pressure source is configured to draw fluid and/or tissue into the suction lumen from a target tissue site at the distal end under negative pressure, e.g., in a range from 300 to 600mmHg, e.g., 550mmHg, such that the fluid and/or tissue is moved away from the tissue site and transported along the suction lumen and out the proximal end, e.g., into a waste reservoir. In some embodiments, the irrigation lumen and the aspiration lumen may be separate lumens, while in other embodiments, the irrigation lumen and the aspiration lumen may be included in a single lumen, e.g., as concentric tubes with an inner tube provided for aspiration and an outer tube provided for irrigation. When present, the lumen of the device with irrigation functionality may be operably coupled to an extracorporeal irrigation device, such as a fluid source, positive and negative pressure, and the like. Where desired, the irrigator and/or aspirator may be steerable, as described above.

Where desired, the device may include a control structure, such as a handle, operatively connected to the proximal end of the elongate member. By "operatively connected," it is meant that one structure is in communication with another structure (e.g., mechanically, electrically, optically, etc.). When present, a control structure (e.g., a handle) is located at the proximal end of the device. The handle may have any convenient configuration, such as a hand-held wand with one or more buttons, such as a hand-held gun with a trigger, and the like, examples of suitable handle configurations are provided further below.

In some embodiments, the distal end of the elongate member is rotatable about its longitudinal axis while a substantial portion of the lever remains in a fixed position. Also, at least the distal end of the elongate member may be rotated through some angle while the handle attached to the proximal end of the elongate member remains in a fixed position. The angle of rotation of a given device may vary and may range from 0 to 360, such as from 0 to 270, including from 0 to 180.

The device of the present invention may be disposable or reusable. Likewise, the devices of the present invention may be all reusable (e.g., as a multi-purpose device), or all disposable (e.g., where all of the components of the device are used once). In some examples, the device may be reusable all of a number of times (e.g., where all components may be reusable a limited number of times). Each of the components of the device may be individually disposable, have limited reusability, or be infinitely reusable, resulting in an overall device or system composed of components with different usability parameters.

The devices of the present invention may be fabricated using any convenient material or combination thereof, including but not limited to: metallic materials such as tungsten, stainless steel alloys, platinum or alloys thereof, titanium or alloys thereof, molybdenum or alloys thereof, and nickel or alloys thereof; polymer materials such as polytetrafluoroethylene, polyimide, PEEK (polyetheretherketone), and the like; ceramics, e.g. alumina ceramics (e.g. STEATITE)^TMAlumina porcelain, MAECOR^TMAlumina porcelain), and the like.

Additionally, the device of the present invention may include a distally integrated non-visualization sensor. In other words, the device may include one or more non-visualization sensors integrated at the distal end of the elongate member. It should be understood that although the non-visualization sensor is described herein primarily with respect to a tissue modification device having a non-visualization sensor at a distal end, other minimally invasive devices may also include a non-visualization sensor located at a distal end.

The one or more non-visualization sensors are sensors configured to obtain non-visible data from the target location. The non-visible data includes, but is not limited to: temperature, pressure, pH, elasticity, impedance, conductivity, distance, size, etc. The non-visualization sensors include those configured to obtain one or more types of the non-visible data. Examples of sensors that may be integrated at the distal end include, but are not limited to: temperature sensors, pressure sensors, pH sensors, impedance sensors, conductivity sensors, elasticity sensors, and the like. Specific types of sensors include, but are not limited to: thermistors, strain gauges, including diaphragm sensors, MEMS (micro-electro-mechanical systems) sensors, electrodes, optical sensors, and the like. The particular type of sensor chosen will depend on the nature of the non-visible data. For example, the pressure sensor may detect a force applied to the target tissue as the pressure sensor is deformed to determine the elastic modulus of the target tissue. A temperature sensor may be used to detect locally elevated temperatures (which may be used to distinguish between different types of tissue, e.g. between different normal and tumour tissue (tumours showing increased blood flow and therefore higher temperatures)). A suitably calibrated laser beam may be used to determine the distance to an object located within the field of view of the device, or the proportion of the length of an object located within the field of view of the device. When present, the integrated non-visualization sensor may be configured to complement other distal components of the device, minimizing any impact on the outer profile of the distal end, e.g., in a manner similar to those described in connection with the integrated illumination element.

The apparatus of the present invention may also include shielded components, such as components that are shielded from the surrounding RF field. It should be understood that although the structures with RF shielding are described herein primarily with respect to tissue modification devices with RF shielding, other minimally invasive devices may also include RF shielding.

In certain embodiments, a develop module including one or more develop sensors may include an RF shield. The RF shielded developing sensor module is integrated with the long member. Since the RF shielded development sensor module is integrated with the elongated member, the RF shielded development sensor module cannot be removed from the elongated member and the rest of the apparatus without significantly compromising the structure and function of the apparatus. Thus, the device of the present invention differs from devices that include a "working channel" in which different independent autonomous devices pass through the working channel. In contrast to these devices, since the RF shielded development sensor module of the device of the present invention is integrated with the long member, it is not the following device: a device which is independent with respect to the elongated member, which is present only in the elongated member working channel and which can be removed from the working channel of such elongated member without damaging the elongated member in any way structurally. The development sensor module may be integrated with the long member by a variety of different configurations. The integrated configuration includes a configuration in which the development sensor of the development sensor module is fixed with respect to the distal end of the long member, and a configuration in which the development sensor of the development sensor module is movable to some extent with respect to the distal end of the long member. Movement of the visualization sensor module relative to the distal end of the elongate member may also be provided, but then fixed relative to another component present at the distal end, such as a distal-end integrated tissue modifier.

When the development sensor module is RF shielded, the development sensor module includes an RF shield that substantially prevents, if not completely prevents, ambient RF fields from reaching and interacting with the circuitry of the development sensor. Likewise, the RF shield is a structure that substantially prevents, if not completely prevents, ambient RF energy (e.g., when provided by the distal RF electrode) from affecting the circuit function (circuit function) of the visualization sensor.

The RF shield of the developer sensor module can have a variety of different configurations. The RF shield may include an airtight element that functions to shield the circuitry of the development sensor from ambient RF fields. In some examples, the RF shield is a grounded conductive containment that couples the development sensor, the conductive member, and other components of the development sensor module. In some examples, the development sensor of the development sensor module resides within a housing, wherein the housing may include a grounded outer conductive layer that functions as an RF shielding component. In these examples, the RF shield is an outer grounded conductive layer. The conductive enclosure of the RF shielded developer sensor module can be made of a variety of different conductive materials such as metals, metal alloys, and the like, including but not limited to copper foil and the like. In some examples, the RF shield is a metal layer. Such layers, when present, may vary in thickness, but in some examples have a thickness in the range from 0.2mm to 0.7mm, such as from 0.3mm to 0.6mm, including 0.4mm to 0.5 mm.

Further details regarding the RF shielded visualization sensor module are provided in U.S. patent application serial No.12/437,865, the contents of which are incorporated herein by reference. It should be noted that although the RF shielded visualization sensor module is described primarily with respect to a device including a distal integrated tissue modifier, a device including such a visualization sensor module without a distal tissue modifier is also within the scope of the present invention.

The tissue modification devices of the present invention may be configured to be hand-held. Thus, in certain examples, the tissue modification device has a mass of 1.5kg or less, e.g., 1kg or less, including 0.5kg or less, such as 0.25kg or less.

Various aspects of the apparatus embodiments of the present invention have been described above in varying detail. Device embodiments will now be described in further detail with reference to the accompanying drawings. Fig. 1A and 1B provide two different side views of an apparatus 100 according to an embodiment of the invention. The device 100 includes an elongate member 110 and a handle 120 at a proximal end of the elongate member 110. The handle has a gun-type configuration and includes a trigger 125 and a thumbwheel 130, the trigger 125 and thumbwheel 130 providing manual operation by the user to control some function of the device, such as RF electrode positioning and extension. Located at the distal end of the elongate member is an integrated visualization sensor 140 and tissue modifier 150. A control element 160 (which may include suction and irrigation lumens, control/power leads, etc.) exits the handle 120 at a distal region 170, the distal region 170 being rotatable relative to the remainder of the handle 120. There may be a variety of additional components at the distal end of the elongate member, which may include irrigators, aspirators, articulating mechanisms, and the like, as generally described above. More detail about the distal end of the elongate member 110 can be seen in fig. 6D.

Fig. 2A to 2C provide cross-sections of the distal end of an elongate member according to three different embodiments of the device. Each of these views shows how the visualization sensor and the tissue modifier may be integrated at the distal end, despite the limited size of the distal end.

Fig. 2A shows an exemplary cross-sectional view of a distal end 200 of an elongate member of a device according to one embodiment of the present invention. The distal end 200 includes an integrated CMOS development sensor 210, the development sensor 210 having a diameter of 2.5 mm. Also shown is a guide wire 215, the guide wire 215 having a diameter of 1mm and providing articulation for the distal end of the device. The integrated mechanical cutter 230 has a diameter of 1.58 mm. Light source 240 has a diameter of 1.33 mm. Also shown is a lumen 250 that provides for aspiration and irrigation. Fig. 2A is drawn to scale, illustrating that integrated visualization, tissue modification, illumination and irrigation may be located at the distal end of an elongated member having an outer diameter of 5.00 mm.

Fig. 2B shows a cross-section of the distal end of an elongate member similar to that shown in fig. 2A, except that a smaller diameter guidewire (0.80mm) is used. As a result, the light source 240 may have a 1.50mm diameter and the mechanical cutter 230 may have a 1.92mm diameter. Similar to the embodiment shown in fig. 2A, fig. 2B is drawn to scale, illustrating that integrated visualization, tissue modification, illumination, and irrigation may be located at the distal end of an elongated member having an outer diameter of 5.00 mm.

Fig. 2C shows a cross-section of the distal end of an elongate member similar to that shown in fig. 2A, except for the presence of a smaller non-circular cross-section guidewire (1.20mm x 0.60 mm). As a result, the light source 240 may have a 1.63mm diameter and the mechanical cutter 230 may have a 2.22mm diameter. Similar to the embodiment shown in fig. 2A, fig. 2C is drawn to scale, illustrating that integrated visualization, tissue modification, illumination, and irrigation may be located at the distal end of an elongated member having an outer diameter of 5.00 mm.

Fig. 3A shows an exemplary cross-section of the distal end of a device according to an embodiment of the present invention. Fig. 3A illustrates the distal end 300 of the device having a distal outer diameter of 6.6mm, where the figure is drawn to scale. The distal end 300 of the device includes an integrated camera 320 (e.g., a CMOS sensor) having an outer diameter of 2.8mm and two fiber optic light sources 330 each having an outer diameter of 1.3 mm. Also integrated at the distal end are electrode cutters 340 (having dimensions of 2.0mm x 0.7 mm) each associated with an irrigation lumen 350 (having dimensions of 1.2mm x 0.8 mm). In addition, the distal end includes a central aspiration lumen 360, the central aspiration lumen 360 having a rectangular configuration and dimensions of 5.0mm by 1.8 mm. In fig. 3A, the integrated camera 320 overlaps with other elements, and fig. 3A illustrates how the camera cross-section occupies only the space of the distal-most portion 300 of the device. The overlapping portions of the cross-sections of other components, including the aspiration lumen 360, will terminate or turn laterally before reaching the proximal end of the camera. During use of the device for removing tissue from a target tissue site, the following steps may be performed. First, the distal end 300 of the device is introduced through the access device 310 into the target tissue anatomical region. The access device 310 may be any convenient device, such as a conventional retractor tube. The access device 310 shown in figure 3A has an inner diameter of 7.0mm and an outer diameter of 9.5 mm. At this stage, the orientation of the camera 320 is biased to one side (left side in the figure). During insertion, electrode 340 (right side in the figure) on the opposite side of the camera's field of view is translated distally so that electrode 340 protrudes distally from the distal end 300 end of the device. Also, during insertion, distally translated electrode 340 is actuated by supplying RF current and perfusing a conductive fluid, resulting in tissue dissection during insertion of the device. To further dissect tissue to the side toward which the camera is biased (left side in the figure), electrode 340 on the same side of the camera's field of view (left side in the figure) is translated distally so that electrode 340 protrudes laterally from the endoscopic probe on the proximal side of the camera. When translated, the same electrode (left side in the figure) is actuated by supplying the RF electrode and perfusing the conductive fluid, resulting in tissue dissection. At this point, the entire end 300 of the device may be translated proximally and distally so that the desired tissue anatomy is achieved. When tissue dissection in the first position is complete, the device can be rotated 180 degrees and additional tissue removal can be performed using the steps described above.

Fig. 3B shows an exemplary cross-section of a device distal end 300 similar to that of fig. 3A, except that the device distal end in fig. 3B includes an additional irrigation lumen 370 (1.2 mm outer diameter) in addition to the irrigation lumen 350 (1.5 mm x 0.9mm size) coupled to the electrode 340 (2.5 mm x 1.1mm size). Also, the geometry of the draft tube is hexagonal rather than rectangular to maximize the space utilization of this geometry (dimensions 4.2mm by 2.3 mm). The figure is drawn to scale and shows another example of what may be integrated at the distal end of the device having an outer diameter of 6.6 mm. As illustrated, the cross-section of the camera 320 overlaps with other elements, as in fig. 3A, which shows how the camera cross-section occupies space only at the distal-most portion of the device. The overlapping portions of the other cross-sections, including the light source, one of the electrodes, and the aspiration tube, will terminate or turn sideways before reaching the proximal end of the camera. Operation of such a device may include the same steps described above in connection with the device of fig. 3A, except that additional irrigation by use of additional irrigation lumen 370 may be used to help wash out the dissected tissue and clean the camera lens.

Fig. 3C shows an exemplary cross-section of the distal end 300 of a device similar to that shown in fig. 3B, except that the orientation of one of the electrodes 340 is reversed and the geometry of the aspiration tube 360 is trapezoidal instead of hexagonal to maximize the space utilization of this geometry. The figure is drawn to scale and shows another example of a component that may be integrated at the distal end of a 6.6mm outer diameter device. In fig. 3C, the dimensions of the components are the same as in fig. 3B, except that the irrigation lumen 370 has a 1.1mm outer diameter, the dimensions of the aspiration lumen 360 are 4.2mm x 2.7mm, the dimensions of the electrode 340 are 2.5mm x 1.1mm, and the dimensions of the electrode irrigation lumen 350 are 1.5mm x 0.9 mm. As in the device shown in FIGS. 3A and 3B, the camera cross-section overlaps with other elements, and the figure shows how the camera cross-section 320 occupies space only at the distal-most portion of the probe. The overlapping portions of the other cross-sections, including the light source, one of the electrodes, and the aspiration tube, will terminate or turn laterally before reaching the proximal end of the camera 320. Operating such a device may include the same steps as described above in connection with the device of fig. 3A and 3B.

Fig. 3D shows an exemplary cross-section of the distal end 300 of a device similar to that in fig. 3C, except that only one electrode 340 (5.4 mm diameter by 0.35mm thickness in size) is used, and it is much larger than the electrodes present in the device shown in fig. 3C. The electrode lavage lumens were also formed with different sizes, having dimensions of 1.5mm by 0.6 mm. In fig. 3D, the integrated camera 320 is shown with a camera cable 380 (having dimensions of 1.5mm x 0.8 mm). Also, the geometry of the suction lumen is semi-circular rather than trapezoidal to maximize the space utilization of the geometry, where the dimensions of the suction lumen are 3.4mm by 2.1 mm. The figure is drawn to scale and shows an example of components that may be integrated at the distal end of a device having an outer diameter of 6.6 mm. The device is shown residing within an access tube having an inner diameter of 7.2mm and an outer diameter of 9.5 mm. In fig. 3D, the camera 320 cross-section overlaps with other elements as in fig. 3A to 3C, the figure showing how the camera cross-section 320 only occupies space at the most distal part of the probe. The overlapping portions of the other cross-sections, including the light source and the aspiration tube, will terminate or turn sideways before reaching the proximal end of the camera. Operating such a device may include the same steps as described above in connection with the device of fig. 3A-3C, except that a single electrode functions as both electrodes in fig. 3A-3C. The electrode is translated distally only a short distance to make a distal cut, and then it is translated distally further so that it extends laterally to the side viewed by the camera to make tissue dissection on that side.

Fig. 3E shows an exemplary cross-section of a distal probe tip similar to that in fig. 3D, except that one of the irrigation channels is replaced by a probe tool 390 having an outer diameter of 1.2mm, the probe tool 390 being used to manipulate tissue and expose a target tissue region for visualization and/or alteration by a tissue modifier such as an electrode device 340. The figure is drawn to scale and shows another example of a component that may be integrated at the distal end of a device having an outer diameter of 6.6 mm. Operation of such a device may include the same steps as described above in connection with the device of fig. 3A-3D, except that the probe may also be used to probe a region of tissue anatomy and assist in desired tissue anatomy.

FIG. 4 provides a side view of a device according to an embodiment of the present invention, wherein the device includes a side view integrated camera at its distal end. In fig. 4, the device 400 includes an integrated camera 410 with a side or offset lens 420, the integrated camera 410 providing a field of view that includes components viewed from a front and side view of the device. As illustrated, the side view camera is tilted at an angle ranging from 15 to 65 ° relative to the longitudinal axis of the elongated member. The device 400 also includes an integrated tissue cutter 430 (e.g., in the form of an RF electrode) and an integrated light source 435. The device 400 is shown with respect to an intervertebral disc 440, wherein the distal end of the device 400 extends through the annulus fibrosus 450 and into the nucleus pulposus 460.

Fig. 5 provides a side view of a device 500 according to an embodiment of the present invention, wherein the device includes a side-looking integrated camera 510 and two steerable electrodes 530 and 535 at its distal end. In fig. 5, the device 500 includes an integrated camera 510 with a side-looking or offset lens 520. Device 500 also includes steerable integrated electrodes 530 and 535 (e.g., made of shape memory material) and an integrated light source 540. The device 500 is shown with respect to an intervertebral disc 540, wherein the distal end of the device 500 extends through the annulus fibrosus 450 and into the nucleus pulposus 460.

Fig. 6A and 6B are perspective views illustrating an embodiment of the distal end of the tissue modification device of the present invention inserted into an intervertebral disc space. The tissue modification device 600 includes an elongated member 610 inserted through the disc annulus 620 into the nucleus 630 of the disc space. The tissue modification device 600 also includes an RF electrode 640 extending from the distal end of a catheter 650, the catheter 650 extending from the distal end of the elongate member 610. A catheter 650 extends from the distal end of the elongate member 610 and has a curvilinear shape that facilitates access of the RF electrode 640 to the entire intervertebral disc space. The tissue modification device 600 also includes an integrated CMOS visualization element 660 at the distal end of the elongate member 610.

Fig. 6A and 6B provide views of an RF electrode that can be steered at its distal end. In the embodiment shown in fig. 6A and 6B, the steering function of the RF electrode is provided by a shape memory element in conjunction with the catheter. The term "shape memory" as used herein refers to a material that is capable of recovering its original shape after being deformed. In certain embodiments, the shape memory element comprises a shape memory alloy, such as, but not limited to, a nickel-titanium (e.g., NITINOL) alloy, a copper-zinc-aluminum-nickel alloy, a copper-aluminum-nickel alloy, and the like. For example, the steering function of the RF electrode can be provided by a guidewire comprising a shape memory alloy. The shape memory guidewire may be attached to the RF electrode such that when the RF electrode extends from the distal end of the elongate member, the shape memory alloy assumes a predetermined configuration, thus moving the RF electrode to substantially the same configuration. In some examples, a shape memory alloy is provided in conjunction with the catheter. The catheter may be a tube (i.e., a sleeve with a hollow central lumen) disposed inside the elongated member for receiving the RF electrode and for guiding the direction of the RF electrode. Thus, the RF electrode may be disposed within the central lumen of the catheter. The catheter may be formed of any convenient biocompatible material, such as plastic, rubber, metal, and the like. The catheter may be provided with one or more shape memory elements, such as a guidewire comprising a shape memory alloy, as described above. In certain embodiments, the catheter is a shape memory catheter, such as a catheter comprising a shape memory alloy.

In some examples, the catheter is slidably positioned within the elongate member and may extend from the elongate member distal end. In some examples, the shape memory catheter has a curvilinear shape when extending from the distal end of the elongate member such that the catheter extends at an angle to the longitudinal axis of the elongate member. For example, the catheter may form an arc when the catheter is fully extended from the distal end of the elongate member, wherein the catheter comprises an arc of 1 ° to 360 °, such as 30 ° to 180 °, including 60 ° to 120 °. As described above, the catheter may be provided with an RF electrode located within the central lumen of the catheter. In some examples, the catheter is configured to facilitate access of the RF electrode to the entire intervertebral disc space. In certain examples, access to the entire IVD space is facilitated by articulation of one or more of the RF electrode, the catheter, and the elongate member. Additionally, the RF electrode may be slidably positioned within the catheter and may extend from the distal end of the catheter. The elongate member, RF electrode and/or catheter may be independently rotatable, thereby providing additional accessibility within the IVD space.

In some embodiments, the tissue modification device comprises two or more catheters, wherein the catheters are slidably translatable relative to the elongate member. In some examples, the catheters are slidably translatable relative to each other, which facilitates extending the RF electrode at an angle to the elongate member longitudinal axis, or deforming the electrode tip into a new shape or configuration. Thus, one catheter may be extended or retracted relative to the distal end of the elongate member independently of the other catheter. For example, the movement of each catheter may be controlled by the user so that the user may individually extend, retract, or steer each catheter.

In some examples, the RF electrode includes a guidewire slidably positioned within a shape memory catheter slidably positioned within the elongate member. In certain examples, the RF electrode includes an exposed portion between a first end and a second end, wherein the first end and the second end are each positioned within the shape memory catheter. By "exposed," it is meant that a portion of the RF electrode is capable of achieving electrical contact with the desired target tissue. In these examples, the first end and the second end are linearly translatable, wherein the first end and the second end are translatable in unison such that the first end and the second end extend and retract from the distal end of the elongate member at the same rate. In other examples, the first and second ends are linearly translatable relative to each other such that the first and second ends may extend and retract from the distal end of the elongate member at different rates, or from the distal end of the elongate member to different positions. This facilitates movement of the exposed portion of the RF electrode at an angle to the longitudinal axis of the elongate member. For example, when the RF electrode extends from the distal end of the elongate member, the angle between the RF electrode and the longitudinal axis of the elongate member can be from 1 ° to 270 °, such as 30 ° to 180 °, including 60 ° to 120 °.

As shown in fig. 6A and 6B, RF powerThe pole 640 is a U-shaped structure that includes a distal cutting end (exposed area) bounded on each side by a porcelain member. This U-shaped configuration is further illustrated in fig. 6E. Porcelain members 617 at each side of the distal cutting end 619 can be engaged (e.g., such that they have the crossbar configuration shown in fig. 6A and 6B) or separate components from one another (e.g., as shown in fig. 6E). These components may be made of any convenient ceramic material, including but not limited to alumina ceramics, such as STEATITE^TMAlumina ceramic, MAECOR^TMAlumina ceramics, and the like. In fig. 6E, the extended length of region 619 may vary from 2 to 20mm, for example from 2 to 10mm, and including 2 to 6 mm. The diameter of the conductive lines making up region 619 can vary, and in some embodiments is 180 μm, such as 150 μm or less, such as 130 μm or less, such as 100 μm or less, such as 80 μm or less. While the distal cutting end or region 619 may be made from a variety of materials, in some examples, this portion of the electrode is made from a different material than the material of the electrode lead 621. Such materials from which the distal cutting end 619 may be fabricated include, but are not limited to, tungsten alloys, such as tungsten rhenium, steel, tungsten coated with noble metals, such as Pt, Au, and the like.

Fig. 6C provides a view of the distal end of a device similar to that shown in fig. 6A and 6B. Fig. 6C illustrates how various components, including the integrated CMOS visualization sensor 660, the irrigation lumen 665, the suction lumen 670, and the steerable RF electrode 640, can be incorporated into the distal end of an elongated member having an outer diameter of 7.0mm or less, e.g., 6.5mm or less. The electrodes 640 are comprised of electrode leads extending from an electrode catheter 650. Separating the electrode lead from the distal cutting end 690 is a ceramic electrode crimping element 680. Electrode lead 640 and catheter 650 are shown in an extended configuration in fig. 6C, but electrode lead 640 and catheter 650 may each independently be made of a shape memory material to assume a curved configuration (as shown in fig. 6A and 6B) and thus impart steering capabilities to the RF electrode. As shown in fig. 6C, aspiration lumen 670 is open to the side of device 600 and is positioned just proximal to CMOS image sensor 660 so that these disparate components can all be integrated at the distal end of the device.

FIG. 6D provides a three-dimensional view of one embodiment of the distal end of a tissue modification device 600 (having an outer dimension of 6.5 mm) of the present invention. In fig. 6D, the distal end of the device includes a circular integrated CMOS development sensor 605 and an integrated LED 610. Also shown are a first lavage lumen 615 facing forward and a second lavage lumen 617, the second lavage lumen 617 extending slightly from the distal end and facing sideways so that fluid expelled from the lumen 617 flows across the CMOS visualization sensor 605 to clean the sensor of debris when needed. Also shown is a suction lumen 625 positioned proximally of the irrigation lumens 615 and 617 and the integrated CMOS visualization sensor 605, wherein the suction lumen 625 is configured to aspirate fluid and tissue debris from the target tissue site during use. The distal end also includes steerable integrated RF electrode assemblies 655. The RF electrode assembly 655 includes a NITINOL shape memory catheter 645 extending from an isolated (e.g., RF shielded) guide lumen 642. The RF electrode also includes tungsten cut lines 665, the tungsten cut lines 665 being joined at each end to NITINOL shape memory electrode wire 663 by ceramic arcuate stops 675. As illustrated, the diameter of the cut line 665 is smaller than the diameter of the electrode wire 663, wherein the dimensional difference may vary and may range from 100 to 500 μm, for example 300 to 400 μm.

Referring back to the above, fig. 1A and 1B provide different views of a device according to an embodiment of the present invention, wherein the device includes a distal end as shown in fig. 6D. Fig. 7 provides a cut-away view of the device shown in fig. 1A and 1B. As shown in fig. 7, the device includes a trigger element 125, and the trigger element 125 translates the catheter distally relative to the elongate member. Also shown is a thumbwheel 130, the thumbwheel 130 providing for manual movement of the electrodes relative to the distal end. The cutaway view of fig. 7 shows a mechanical actuator 180, the mechanical actuator 180 providing linear translation for the electrode 150 located at the distal end of the elongated member.

As summarized above, certain embodiments of the devices of the present invention include linear mechanical actuators, such as described in U.S. patent application serial No.12/467,122, the contents of which are incorporated herein by reference. Fig. 19 provides several views of an electric-motor linear actuator that may be present in the device of the present invention to provide linear translation of the RF electrode. As shown in fig. 19, the apparatus includes a motor carrier 1910 that houses an electric motor 1920. The electric motor 1920 includes a bevel pinion 1930 in operative relationship with a bevel pinion 1940. Large bevel gear 1940 is in turn operatively connected to cam follower 1950, and cam follower 1950 is operatively connected to an RF electrode located at drive point 1960.

System for controlling a power supply

Aspects of the subject invention include tissue modification systems, wherein the systems include a tissue modification device, such as described above, operatively connected to one or more extracorporeal control units (i.e., extracorporeal controllers). The extracorporeal control unit may comprise many different components, such as: a power source, a lavage source, a suction source, an image data processing component, an image display component (e.g., a monitor, a printer, etc.), a data processor such as in the form of a computer or the like, a data storage device such as a floppy disk, a hard disk, a CD-ROM (compact disk read only memory), a DVD (digital versatile disk), a flash memory, or the like, a device and system controller, and the like.

An example of a system according to an embodiment of the invention is shown in fig. 8. In fig. 8, the system includes a handheld tissue modification device 800 and an extracorporeal control unit 850. The handheld device 800 includes a distal end 810 and a handle 820 configured to be held within an operator's hand. Positioned at distal end 810 is an integrated visualization component and tissue modification component (as well as other components), as shown in cross-section 830. The extracorporeal control unit 850 includes an image display 860 (e.g., a liquid crystal display monitor), a video digital signal processor 870, an energy source 880 (e.g., configured to operate the RF tissue altering member), and an irrigation/aspiration system 890. The handheld device 800 and the extracorporeal control unit 850 are operatively connected to each other by a cable.

FIG. 9 provides a schematic diagram illustrating the architecture of a system according to one embodiment of the present invention, and how various components of the system may interact with a user, such as a surgeon, during use. In fig. 9, the extracorporeal control unit 910 comprises a video processing unit 911, an RF electrode power supply 912, a lavage source 913, and a suction source 914. Each of these components is operatively connected to an electrical controller 915, and a user 990 can interact with the electrical controller 915 as desired to operate the system. Also shown is a tissue modification device 950, the tissue modification device 950 comprising an integrated visualization sensor 951, RF electrodes 952, irrigation lumen 953, suction lumen 954 and articulation mechanism 955. The tissue modification device 950 provides a number of functions 960 including tissue dissection 961, tissue removal 962, tissue discrimination 963, and access capability 964. The system provides a number of user interface options 930; including an image display 931, tactile feedback 932, and a mechanical controller 933.

The integrated distal visualization subsystem may have a variety of different configurations within a given system. FIG. 10 provides an example of an embodiment of an integrated development subsystem including a remote CMOS development sensor. As shown in fig. 10, the development subsystem 1000 includes a remote CMOS development sensor 1010, the remote CMOS development sensor 1010 including a lens housing member 1015 operatively coupled to an integrated circuit member 1020. As shown in the figure, the lens housing 1015 includes a lens group 1016. Also shown at the distal end is an LED1018, the LED1018 providing illumination of the target tissue site during use. The integrated circuit assembly 1020 includes a CMOS sensor integrated circuit 1021 and a rigid printed circuit board 1022. The sub-components of the lens housing/light source assembly 1015 are operatively coupled to a flexible cable 1030, the flexible cable 1030 providing for operatively connecting a CMOS visualization system at the distal end of the device to a video processing subsystem 1050 via a handle 1040. Within handle 1040, the flexible cable is operatively connected to shielded cable 1052, with shielded cable 1052 providing for RF isolation. As shown in fig. 10, the various components are shielded from RF, for example by coating the elements with a conductive material which is then grounded. For example, the lens housing 1015 and the cable 1030 are RF shielded. RF shielded cable 1052 connects to video processing subsystem 1050, which video processing subsystem 1050 includes a variety of functional blocks such as host controller 1051 (coupled to PC1061), digital signal processor 1054 (coupled to LCD 1062), and CMOS develop sensor bridge 1053. As shown in fig. 10, video processing subsystem 1050 is connected to ground 1072 by being connected to metal shell 1070.

The system of the present invention may include many additional components in addition to the tissue modification device and the extracorporeal control unit, as described above. The add-on component may include an access port device; a root retractor; retractor devices, system component securing devices, and the like. Of interest are systems that further include an access device as described in co-pending U.S. patent application serial nos. 12/269,770, 12/269,772, and 12/269,775; the contents of these U.S. patent applications are incorporated herein by reference.

As described above, some embodiments of the invention include a system having a proximity device. In such embodiments, two or more development elements may be distributed between the distal end of the elongate member and the access means. FIG. 16 provides a cross-sectional view of a distal end of an elongate member of a minimally invasive tissue modification device and an access device, according to one embodiment. In fig. 16, the distal end of the elongate member 1620 includes a first imaging sensor 1621 and the distal end of the proximity device 1622 includes a second imaging sensor 1623. Also shown at the distal end of the elongate member 1620 are first and second LEDs 1624 and 1625. An irrigation lumen 1626 and an aspiration lumen 1627 are also shown. In addition, the device includes a tissue modifier in the form of an anatomical electrode 1628 (e.g., an RF electrode). In the system of fig. 16, a first imaging sensor 1621 provides visualization of the target tissue site. The second imaging sensor 1623 is located on the proximity device (although it could be located at multiple locations on the proximity device or the elongated member). The orientation of the second imaging sensor 1623 is such that the imaging sensor 1623 provides image data of the elongate member, such as at the distal end of the elongate member during placement. Any convenient location when in use can be achieved.

Figure 17 provides different views of an access device according to an embodiment. As shown in fig. 17, the access device 1730 includes a distal end 1731. Positioned at the distal end 1731 are two cameras 1732A and 1732B and two illumination sources 1733A and 1733B, such as LEDs or optical fibers. Passing through the length of the access device and exiting proximally are wires 1734 and 1735, the wires 1734 and 1735 being used to provide power and control for the camera and visualization elements, for example, by coupling to a control device.

The multiple development and/or illumination elements of the device may be positioned relative to one another in a number of different ways. By selectively positioning these pairs of elements, as desired, unique images of the target tissue site may be obtained with the aid of specific image processing techniques. For example, as shown in FIG. 18, two cameras 1842 and 1844 may be located within the same cross-section of the distal end of an imaging device 1840 (e.g., a minimally invasive tissue modification device and/or a proximity device). In such an embodiment, the image data from the two cameras may be combined to obtain a panoramic view of the target tissue site, in this example, the nucleus 1814 located within the annulus 1812. This configuration also allows us to obtain a stereoscopic image of the target tissue site, for example by synchronizing the image data from the two cameras.

Placing the development elements in different cross-sections of the device and/or on different devices may also provide imaging advantages. For example, fig. 16 provides a view of the distal end of a system comprised of a minimally invasive tissue modification device slidably positioned within an internal passage of an access device, such as a retractor tube. In the embodiment depicted in fig. 16, the primary camera 1621 is located on a cross-section of the tissue modification device and the secondary camera 1623 is located on a wall of the access device. Both cameras may be arranged to have certain orientations, such as toward the front or at an oblique angle or toward the sides, as desired. The illumination may also be arranged such that different views of the same object may be displayed. For example, the light source may be substantially collimated or focused in a certain direction to more clearly view the surgical blade, electrode, or local tissue appearance.

Image processing module

Embodiments of the apparatus and system of the present invention may include one or more different types of image processing modules. In some examples, the inventive device may include a stereoscopic imaging module having one or more visualization sensors located at a distal end. The "stereoscopic image module" is a functional module for providing stereoscopic images from image data obtained by the apparatus. Also, the module enables the user to perceive, by means of the monitor, a three-dimensional view of the image produced by the image data obtained by the device. Although the modules are described in terms of "images," it should be understood that the description applies equally to photographic images and video. The device may include two or more different visualization sensors or a single visualization sensor through which image data is collected and employed by the stereoscopic imaging module to provide stereoscopic images. In the case where the long member includes the first and second developing sensors, the stereoscopic image module is configured to process image data provided by the first and second developing sensors to generate a stereoscopic image.

In such embodiments, any convenient stereoscopic image processing procedure may be employed. FIG. 11 illustrates a block flow diagram of a technique for generating stereoscopic imagery from imagery data, according to one embodiment. Left and right image data are obtained (as represented by block 1105), either sequentially by a single development sensor moving from a first location to a second location, or sequentially or simultaneously if there are two development sensors. The left and right image data allow for different positions and perspective views associated with respective positions of the same visualization sensor or respective positions of two different visualization sensors. The image data for the first and second images may include distortion, and algorithms may be utilized, for example, where the left and right image data are first deformed as illustrated by means of a calibration element to remove lens distortion, as illustrated by block 1110. Any convenient algorithm may be employed. The algorithm comprises the following steps: those described in "geometrical Calibration of Digital Cameras through Multi-view retrieval" by Luca Lucchese (Image and Vision Computing, Vol. 23, No.5, 5.2005, p. 517-539); and "Correction of geometrical Lens departure through Image Warping" by Lucchese (ISPA 2003, Proceeding of the 3^rdLevenberg-Marquardt algorithm described by International Symposium on Image and Signal Processing and Analysis, 18-20 9 months 2003, Vol.1, pp.516-521). Then, the generated represented by block 1115Undistorted left and right images are processed with a stereo and image fusion algorithm to construct stereo images, as represented by blocks 1120, 1122, 1124, 1126, 1128. Any convenient stereo and image fusion algorithm may be employed, such as, but not limited to, those described below: "Scene Reconstruction from Multiple Cameras" (Microsoft Vision Technology Group; see also, Microsoft Vision Technology Group; of Richard Szeliskihttp://research.microsoft.com/pubs/75687/Szeliski-ICIP00.pdf) (ii) a Nishimoto and Y.Shirai, "A parallel matching algorithm for stereo vision" (IJCAI-1985-Vol.2, page 977; see alsohttp://ijcai.org/Past％20Proceedings/IJCAI-85-VOL2/PDF/059.pdf) (ii) a ZhuShu Shu-long "Image Fusion Using Wavelet Transform" (Institute of Surveing)&Mapping; commission IV, Working Group IV/7; see alsohttp://www.isprs.org/commission4/proceedings02/pdfpapers/162.pdf) (ii) a Tzovaras, "resolution field and depth map coding for multiview 3D Image generation" (Image Communication, Signal Processing; 1998, volume 11, n ° 3, pages 205-230); and so on.

The stereo algorithm calculates range information of an object observed by the development sensor by using triangulation. An object viewed at different observation points will cause the object to be located at different positions in the image data of the first and second development sensors. Parallax or image disparity is used to determine object depth and range. Corresponding pixel points within the image data of the first and second development sensors may be identified and used to determine a disparity line (disparity line), as represented by block 1124. Since the first and second development sensors are located at different positions and thus have different perspective views, the same object present in the image data of the first and second development sensors may be located at different pixel coordinate positions. Triangulation may be implemented, as represented by block 1126, which may be used to determine the depth and range of an object viewed by the visualization sensors based on the geometry associated with the positions of the first and second visualization sensors. Triangulation calculations are applied to acquire range data and the resulting range (or depth) map may be overlaid on the image sensor as desired. This is indicated by block 1128 in FIG. 11. Accordingly, a stereoscopic image in which three-dimensional depth information is considered may be reconstructed from image data from the first and second development sensors.

FIG. 12B illustrates a slightly offset development position according to some embodiments. Fig. 12B illustrates two development sensors, namely 1242 for a first view of objects a and B and 1244 for a second view of objects a and B. The depth and extent of the object are found in a similar manner in fig. 12A, as described below. Further details regarding stereoscopic imaging modules that employ image data obtained from two or more different imaging sensors may be found in U.S. patent application serial No.12/269,770; the contents of this U.S. patent application are incorporated herein by reference.

Also of interest is a stereoscopic image module configured to provide stereoscopic images from data obtained by a single image sensor. In such embodiments, the image sensor is configured to provide successive offset image data of the target tissue location to the stereoscopic image module, which is then used by the stereoscopic image module to provide the desired stereoscopic image. By "continuously shifted image data", image data is meant that includes at least data from a first view of a target tissue location and data from a second view of the same target location, where the second view is shifted from the first view. The second view may be offset from the first view by any convenient distance, such as 1mm or less, including 0.5mm or less. The first and second offset views may be obtained using any convenient approach. In one approach, a single development sensor is moved from a first position to a second position to obtain the desired offset image data. The single development sensor may be moved from the first position to the second position using any convenient means, such as by mechanical elements that physically move the sensor from the first position to the second position. In still other embodiments, the desired may be obtained by means of a single visualization sensor operatively coupled to an optical guidance system (which may include one or more lenses, mirrors, filters, etc.) configured to provide the desired first and second offset viewsOffset view of (a). For example, the first and second offset views may be provided to a single development sensor by including first and second lens systems that alternately transmit image data to the development sensor. The offset view may also be provided, for example, by including a single lens system with a mirror configured to provide two or more different views to the lens. The frequencies utilized to obtain the first and second offset views may vary, where in some examples, the frequencies may range from 1 to 30 frames/second, such as 1 to 15 frames/second. Various systems may be implemented to provide multiple views with a single camera. Such systems include, but are not limited to, those described in the following: hill, "Scalable Multi-view Stereo Camera Array for Real World Real-Time Image Capture and Three Dimensional display" (Mass of Technology, Program in Media Arts and Sciences School of Architecture and Planning; 5 months and 7 days 2004; see also http:// web. "Single Camera Stereo Using Planar Plate" by Chunyu Gao et al (Beckman Institute, University of lllinois at Urbana-Champiagn; see alsohttp://vision.ai.uiuc.edu/newpubs/Stereo PPP Gao.pdf) (ii) a And "3-D Reconnection Using Mirror Images Based on a Plane Symmetry recovery Method" by Mitsumoto, H. et al (IEEE transfer on Pattern Analysis and Machine understanding; volume 14; phase 9, 1992, month 9, pages 941-946).

Fig. 12A illustrates a single development sensor 1205 moved to two different positions (1201 and 1202) to sequentially obtain image data, which is employed by the stereoscopic image module to generate stereoscopic images of objects a and B. First and second image locations 1201 and 1202 are spaced apart from each other by an offset width W that may vary, in some examples, in a range of 1mm or less, such as 0.5mm or less. Objects a and B at the focal plane distance Z are observed at different perspective views (shown by dashed lines 1215, 1220, respectively) at the first and second locations. The differences when viewing the perspective view are reflected in the image data obtained by the single sensor from the first and second positions. As illustrated, the development sensor 1205 observes the objects a and B shifted to the right of the center at the position 1201, and observes the objects a and B shifted to the left of the center at the position 1202. The disparity between the two views is used to determine the depth and range of objects a and B.

The stereoscopic image module may be implemented in a video processor module configured to receive image data obtained by one or more development sensors. The stereoscopic image module processes the image data to provide stereoscopic image data for display on a display. FIG. 13 illustrates a functional block diagram of portions of a system 1300 including a video processor module 1305, according to one embodiment. The video processor module 1305 includes a processor/controller module 1310, the processor/controller module 1310 in communication with a sensor module 1360, a camera module 1350, and a display 1380. The processor/controller module 1310 includes a front-end module 1315, a back-end module 1320, a microcontroller 1330, and an image co-processing module 1340. The image co-processing module 1340 includes, for example, a stereoscopic image module, and performs the aforementioned functions and operations of the stereoscopic image module.

Camera module 1350 may include a single development sensor, or two or more development sensors, that provide image data. The front end module 1315 includes circuitry for receiving image data from the camera module 1350. The image data received from the camera module 1350 is processed by a stereoscopic image module (i.e., by the image co-processing module 1340) to provide stereoscopic image data. For example, as previously described, image data from the various different visualization sensors may be deformed to correct image distortion and fused to construct a single stereoscopic image that takes into account three-dimensional depth information. The back end module 1320 includes circuitry for transmitting stereoscopic image data to a display 1380. The display 1380 displays a three-dimensional view of the image data for viewing by a user.

The video processor module 1305 may be electrically coupled to the camera module 1350 via an I2C bus, for example, with the camera module 1350 configured as a slave and the microcontroller 1330 configured as a master. The microcontroller 1330 may be configured to send camera control data to the camera module 1350. The camera control data may include information requests (e.g., for test/debug related information, for calibration data, etc.) or provide instructions for controlling the camera module 1350 (e.g., controlling two or more different development sensors, etc.).

The sensor module 1360 may include one or more of the sensors and/or tools previously described. One or more sensors and/or tools implemented may provide sensor data related to their specific function and application. The sensor data is received by the processor/controller module 1310 and may be used in a variety of ways depending on the particular function of the sensor and/or tool and their application. For example, sensor data may be used by the processor/controller module 1310 to provide information to a user (e.g., parameter data to be displayed on the display 1380 or to illuminate one or more LEDs, calibration data, measurement readings, warnings, etc.), to take into account feedback signals for more precise control of a particular sensor and/or tool, to store in memory, to further process additional related information, etc. The microcontroller 1330 may also control the sensor module 1360 via an I2C bus or general purpose input/output (GPIO) interface and by sending sensor control data (e.g., to control and/or calibrate the particular sensor and/or tool implemented).

The processor/controller module 1310 also includes various modules for interfacing with external devices and peripherals. For example, as shown in fig. 13, the processor control module includes keypad and switch circuitry 1370 for receiving input signals from user keypads and switches on the device, SD (secure digital card) card holder circuitry 1372 for sending/receiving data stored in the storage device, and motor control circuitry 1374 for controlling the rotation of the camera. The microcontroller 1330 may be configured with GPIOs to communicate with various circuits, for example. Further, the video processor module 1305 may include a communication interface for implementing a test or debugging program, such as UART (universal asynchronous receiver/transmitter), USB (universal serial bus), or the like.

The development system may include an image processing component that manipulates the image data in some manner, such as to collate the data, to obtain information from the data, to take one or more actions based on the obtained information, and so forth. The image processing component may be physically embedded within any convenient component of the system, such as within an extracorporeal processing unit, within a minimally invasive device, and the like. It should be understood that although the image processing components are described herein primarily with reference to minimally invasive tissue modification devices having (or in communication with) image processing components, other minimally invasive devices may implement (or in communication with) image processing components.

Additional details regarding the stereoscopic image processing module are provided in U.S. patent application serial nos. 12/269,770 and 12/501,336; the contents of these U.S. patent applications are incorporated herein by reference. It should also be understood that although the stereoscopic image module is described herein primarily with reference to minimally invasive tissue modification devices having an integrated tissue modifier at the distal end, other minimally invasive devices may also implement the stereoscopic image module of the present invention, wherein such devices may include a distal integrated tissue modifier and still fall within the scope of these embodiments of the present invention.

In some embodiments, there may be an image processing module that compares image data to reference data. The image processing module of these particular embodiments is a processing module configured to receive image data and compare the received image data with reference data comprising at least one of color descriptor data and anatomical descriptor data to determine whether an alarm signal should be generated.

The image data received by the image processing module can be changed. In some examples, the image data is data obtained from a development sensor. The received image data may be data for one or more photographic images or video data. Thus, the image data can be utilized by the image processing component to generate and output a photographic image or video. When the image data is video data, the image processing module may be configured to perform its function in real time, such that the image processing module is configured to process the video data in real time. The term "real-time" is used in its ordinary sense to mean that the image processing module compares the received image data to the reference data at the same rate as the image data is received.

In some embodiments, the received image data includes a comparator component. The comparator component is a component that can be used to compare the received image data with reference data (the reference data is described in more detail below). Such a comparator component may be any convenient data component that allows for accurate comparison of the received data with data for one or more reference data images. Although any convenient comparator component may be employed, in some examples, the comparator component is comprised of one or more predetermined reference elements in the image. The one or more predetermined reference elements in the image may be virtual points or actual structures present in the image. In either case, the reference element may be at a known position in the image relative to the development sensor used to obtain the image based on its position in the image. Similarly, in the case where the reference element is an imaginary point, the imaginary point may be a point in space in the image calculated with respect to the development sensor that acquired the image. Any convenient protocol for determining the virtual reference element may be employed. Alternatively, where the reference element is an actual structure in the image, the actual structure in the image may be a structure of the device that is present in the image and is located at a known position relative to a development sensor of the device.

In some examples, the reference elements of one or more images of the received image data are actual structural elements of the device used to obtain the image data. The structural element of the device may be any device component present in the image obtained by the development sensor. In some examples, the structural element is not used for any purpose other than being a reference element in an image obtained by the development sensor. For example, the structural element may be a wire or similar structure that protrudes from the distal end of the device into the field of view of the development sensor and is thus captured into the image data obtained by the development sensor. In still other embodiments, the structural element serves one or more purposes in addition to merely serving as a reference element for the image. For example, the structural element may be a tissue modifier, such as an RF electrode, such as described in more detail below. In these embodiments, the structural element provides one or more additional functions, such as tissue modification. Any structure of the device that is located within the field of view of the camera can serve as a structural element and thus as a reference element.

As summarized above, the image processing module is configured to compare the received image data with reference data. The term "reference data" is used herein to refer to data in any format, such as data stored as one or more image files, etc., that are used in one or more reference images, such as where the data may be utilized by an appropriate processor to generate one or more reference images. Also, the reference data includes at least a first set of reference image data for the first reference image. In some examples, the reference data also includes a second set of reference picture data for a second reference picture. In these embodiments, the reference data may include multiple sets of reference image data for multiple reference images, such as 2 or more, 5 or more, 10 or more, 25 or more, 50 or more, 100 or more, 1000 or more, 1500 or more, 2000 or more, 5000 or more, 10000 or more, etc. reference images.

The reference image is a predetermined image of the region of interest. Because the reference images are predetermined, they are generated independently of the image data received by the image processing module. In some examples, the reference image is an image that existed prior to obtaining the image data received by the image processing module. The reference image may be an image obtained from the same object (e.g., a person) being visualized in a given procedure (e.g., in the case of a reference image obtained from the object prior to the given procedure), or from a different object (e.g., a person). Alternatively, the reference images may be generated ab initio such that they are not generated from image data acquired by any actual object, but instead are designed, for example, by using manual or computer-aided graphics protocols.

The reference images that constitute the reference data may differ from one another in many ways. For example, any two given reference images may be images of regions of interest at different internal tissue locations. In such reference data, the reference data may include first and second predetermined images that are different from each other with respect to a predetermined internal tissue location. For example, the reference data may comprise images of at least a first tissue location and a second tissue location. The first and second tissue locations may be locations where imaging of a given device is desired during a given procedure, such as a surgical procedure. In some examples, the reference data includes multiple images of different locations that a given visualization sensor should image during a given procedure when the procedure is properly performed. The reference data may also include images of different tissue locations that should not be observed by the visualization sensor during a given procedure, such as tissue location images that should not be observed by the sensor when the given procedure is not performed properly. Thus, some reference data may include multiple images that track the position of the device when properly and incorrectly positioned throughout the procedure, such as the entire surgical procedure.

The set of image data in the reference data may include one or more of color descriptor data and anatomical descriptor data. Data of a particular color based on a given internal tissue site and its composition is represented by "color descriptor data". For example, the internal tissue site may include one or more tissues each having a different color. For example, different tissues such as muscles, nerves, bones, etc. may have different colors. The different colors may be present in the reference image as color descriptor data and may be used by the image processing module. Data based on a particular shape of one or more tissue structures at an internal tissue site is represented by "anatomical descriptor data". For example, different tissues such as muscles, nerves, bones, etc. have different shapes. These different shapes are present in the image data as anatomical descriptor data.

As summarized above, the image processing module compares received image data of the internal tissue site (e.g., obtained during a given procedure) with reference data. The comparison performed by the image processing module may be implemented using any convenient data processing protocol. A data processing protocol employable in the comparing step may compare the number of images received with the reference data based on the color descriptor data and/or the anatomical descriptor data. Data comparison protocols include, but are not limited to: the average absolute difference between the data descriptors, such as the average color intensity, and the stored values, and the degree of correlation between the principal axis of the structure and the stored values.

In performing the comparing step, the image processing module may be configured to automatically select an appropriate image from the reference data to compare the received image data. In some examples, the image processing module is configured to compare the received image data with reference data by selecting an appropriate set of reference image data based on the determined positional location of the device. For example, the image processing module may obtain positioning information about the device (e.g., information obtained from sensors on the device or manually input and associated with a given image), and then select a reference image for positioning at the same location as the device when the device that acquired the image data is being received. Alternatively, the image processing module may automatically select an appropriate set of image data based on the similarity parameter. For example, the image processing module may automatically select the image data of the most similar group from the reference data for the comparison step.

The image processing module compares the received image data with reference data to determine whether an alarm signal should be generated. In other words, the output of the image processing module is a decision as to whether or not an alarm signal should be generated. If the image processing module determines that an alarm signal should be generated, the image processing module may generate an alarm signal or instruct an independent module of the system to generate an alarm signal.

The alarm signal, when generated, may vary depending on the nature of the system. The alarm signal may be a warning signal regarding a given system parameter, or a signal to the system operator to confirm that the given system parameter is acceptable. In some embodiments, the alarm signal may include functional information about the device. For example, in these embodiments, the alarm signal may include information that a given device is functioning properly, such as information that the tissue modifier has not been damaged in some way. For example, one problem that can occur during a surgical procedure is the breakage or loss of the RF electrode. The image processing module can automatically detect the occurrence and generate an alarm signal to provide a user with information that the RF electrode has been broken. In some embodiments, the alarm signal may include location information about the device. For example, the alarm signal may include information regarding whether a given device (or component thereof, such as a tissue modifier) is properly spatially located. In these embodiments, the alert signal may include information that the tissue modifier of the device is in contact with non-target tissue such that the tissue modifier is not properly spatially located.

The system may be configured to utilize the alarm signal in a number of different ways. The system may be configured to provide an alarm signal to a user of the system, for example via an alarm signal output of the system. Additionally or alternatively, the system may be configured to automatically modulate one or more operating parameters of the system based on the generation of the alarm signal. For example, in the event that the image processing module determines that the tissue modifier is contacting non-target tissue and therefore generates an alert signal, the alert signal may automatically modulate the operation of the tissue modifier, such as by turning off the tissue modifier. In some examples, the alarm signal may cause the system to automatically shut down.

The image processing module may be implemented as software, such as digital signal processing software, as desired; hardware such as circuitry; or a combination thereof. Fig. 14 provides a flowchart of an image processing module according to an embodiment. In fig. 14, the image processing module 1400 powers up at 1405. After power is turned on at step 1405, the system loads reference data made up of sets of image data corresponding to the region of interest 1410 and the color descriptor 1420 and anatomical descriptor 1425. Next, the system receives video image data at step 1430 and processes the received video image data at step 1440. For each given frame of video, the image processing module 1400 selects color and anatomy descriptors at step 1450 and compares the received image data with reference descriptors using these selected descriptors. At step 1470, the system determines whether an alarm signal is generated. The system may decide whether to generate an alarm signal based on many different alarm signal thresholds. The alarm threshold is a value for an image parameter, such as a structural element (e.g., a tissue modifier), a color descriptor, a structural descriptor, etc., in the image. If the threshold is not exceeded (e.g., the system finds that the correct color or structure is present in the image), the image processing module may continue to move to the next frame of video image data, as shown. Alternatively, if the threshold is exceeded such that at least one of the correct colors and/or structures is not present in the image, the image processing module generates an alarm signal at step 1480. The alarm signal may comprise many different types of information, such as providing a user (e.g., a surgeon) with a simple warning that something wrong with the system and/or procedure is occurring, such as whether the tissue modifier is damaged, the tissue modifier is not properly positioned, etc. In these examples, the user may use the alarm signal as an indication to stop or change the surgical parameters. In some examples, the alert signal may automatically change an operating parameter of the system in some manner, such as by automatically changing an operating parameter of the tissue modifier, by shutting down the system, or the like.

Additional details regarding such image processing modules configured to compare reference data are provided in U.S. patent application serial No.12/437,186, the contents of which are incorporated herein by reference. It should be noted that although the image processing module of these embodiments is described in terms of an image processing module for use with a device that includes an integrated distal tissue modifier, devices that do not include an integrated distal tissue modifier are also encompassed by these specific embodiments of the present invention, as the image processing module may be used with a variety of different types of devices.

As described above, in certain embodiments, the processor may be configured to generate video from image data obtained under white light, or under near infrared light, or a combination of data acquired under both illuminations, i.e., to generate polychromatic spectra or a combined video. For example, if the target tissue site is relatively free of fluid, the user may desire to view the site under white light illumination. Alternatively, where the target tissue site is filled with fluid, the user may desire to view the site under near infrared illumination.

FIG. 15 provides a schematic diagram of an operational framework of a processor configured to generate video from image data obtained under white light and/or near infrared light, according to an embodiment. As shown in fig. 15, after the camera turns on the power supply 1531, the camera obtains a NIR light buffer 1532 of a video frame with a NIR LED (near infrared light emitting diode) on and white light off 1533. In addition, with the NIR LED off and white light on 1535, the camera obtains a white light buffer 1534 of video frames. The generated video data is processed at step 1536 to produce a combined video with depth 1537. At step 1538, the user is provided with the option of viewing a white light video obtained under white light illumination only, or viewing a combined video of a video obtained under white light illumination and a video obtained under near infrared light illumination. By "combined video", a video image is meant that combines image data obtained under white light illumination and near infrared light illumination. Although not shown in fig. 15, the processor may also be configured to provide the user with the option of viewing image data of only near infrared light. The user's selection can be used to control the LEDs, as shown at step 1539.

Method

Aspects of the invention also include methods of imaging and/or altering internal target tissue of a subject. Accordingly, aspects of the present invention also include methods of imaging an internal tissue site with the tissue modification devices of the present invention. Multiple internal tissue sites can be imaged with the device of the present invention. In some embodiments, the method is a method of imaging an intervertebral disc in a minimally invasive manner. For ease of description, the method will now be further described primarily in terms of imaging an IVD target tissue site. However, the present invention is not so limited as these devices may be used to image a plurality of different target tissue sites.

With respect to imaging an intervertebral disc or portions thereof, such as the exterior of an intervertebral disc, the nucleus pulposus, etc., embodiments of these methods include positioning the distal end of the minimally invasive intervertebral disc imaging device of the invention in viewing relation to the intervertebral disc or portions thereof, such as the nucleus pulposus, an interior portion of the nucleus pulposus, etc. By "viewing relationship", it is meant that the distal end is positioned within 40mm, such as within 10mm, including within 5mm, of the target tissue site.

The method of the present invention may include obtaining image data of the internal tissue site with the aid of a visualization sensor and then forwarding the image data to an image processing module of the system of the present invention. The method of the present invention may also include receiving image data into a system including the image processing module of the present invention. The method also includes viewing an image generated from the image data received by the image processing module.

Positioning the distal end within the viewing device relative to the desired target tissue may be accomplished using any convenient approach, including by using an access device such as a cannula or retractor tube, which may or may not be equipped with a trocar as desired. After positioning the distal end of the imaging device in viewing relation to the target tissue, such as an intervertebral disc or portion thereof, is imaged by using the illumination and visualization elements to obtain image data. The image data obtained according to the method of the present invention is output to the user in the form of an image, for example, by using a monitor or other convenient medium as a display device. In some embodiments, the image is a photographic image, while in other embodiments, the image may be a video.

In certain embodiments, the method comprises a tissue modification step in addition to tissue observation. For example, the method may comprise a tissue removal step, for example using a combination of tissue cutting and irrigation or irrigation for tissue removal. For example, the method may include cutting at least a portion of the tissue and then removing the cut tissue from the site, such as by flushing at least a portion of the imaged tissue site with fluid introduced by an irrigation lumen and discharged by an aspiration lumen.

The internal target tissue may vary widely. Including but not limited to cardiac locations, vascular locations, orthopedic joints, central nervous system locations, and the like. In some examples, the internal target tissue site includes spinal tissue.

The subject methods are applicable to a variety of mammals. Such mammals include, but are not limited to: sports objects such as horses, dogs, etc.; working animals such as horses, cattle, etc.; and humans. In some embodiments, the mammal in which the subject methods are practiced is a human.

An example of a method employing the apparatus depicted in fig. 3A includes the following steps. First, the distal end 300 of the device is introduced into the target tissue anatomy via the access device 310. The access device 310 may be any convenient device, such as a conventional retractor tube. The access device 310 shown in fig. 3A has an inner diameter of 7.0mm and an outer diameter of 9.5 mm. At this stage, the orientation of the camera 320 is biased to one side (left side in the figure). During insertion, electrode 340 (right side in the figure) on the opposite side of the camera's field of view translates distally so that it protrudes distally from the distal tip of device 300. Also, during insertion, distally translated electrode 340 is actuated by supplying RF current and perfusing a conductive fluid, resulting in tissue dissection during insertion of the device. To further bias the camera toward tissue dissection to one side (left side in the figure), the electrode 340 on the same side as the camera field of view (left side in the figure) is translated distally so that it protrudes laterally from the endoscopic probe on the proximal side of the camera. Upon translation, the same electrode (left side in the figure) is actuated by supplying the RF electrode and perfusing the conductive fluid, resulting in tissue dissection. At this point, the entire end of the device 300 may be translated proximally and distally until the desired tissue anatomy is achieved. When tissue dissection in the first position is complete, the device can be rotated 180 degrees and further tissue removal can be performed using the steps described above.

Practicality of use

The subject tissue modification devices and methods are useful in many different applications where it is desirable to image and/or modify internal target tissue of a subject while minimizing damage to surrounding tissue. The subject devices and methods find use in a wide variety of applications, such as, but not limited to, surgery, where many different types of tissue may be removed, including, but not limited to: soft tissue, cartilage, bone, ligaments, etc. Specific procedures include, but are not limited to: spinal fusion procedures (e.g., transforaminal lumbar interbody fusion, TLIF), artificial Total Disc Replacement (TDR), artificial Partial Disc Replacement (PDR), procedures to remove all or part of the nucleus pulposus from the disc (IVD) space, arthroplasty procedures, and the like. Likewise, the methods of the present invention also include methods of treatment, such as altering the intervertebral disc in some way to treat conditions of an existing medical condition. Such treatment methods include, but are not limited to: annulectomy, nuclectomy, discectomy, annulus replacement, nucleus replacement, and decompression due to herniation or herniation of the disc. Additional methods in which the imaging device may be used include those described in U.S. published application No. 20080255563.

In certain embodiments, the subject devices and methods facilitate nucleus pulposus dissection while minimizing thermal damage to surrounding tissue. In addition, the subject devices and methods may facilitate a surgeon's access to the entire area or annulus within the outer shell of an IVD during dissection and removal of the nucleus while minimizing the risk of cutting or otherwise damaging the annulus or other adjacent structures (e.g., nerve roots).

In addition, the subject devices and methods may be used in other procedures, such as, but not limited to, ablation procedures, including high power focused ultrasound surgical ablation, cardiac tissue ablation, tumor tissue ablation (e.g., cancer tissue ablation, sarcoma tissue ablation, etc.), microwave ablation, and the like. Other applications of additional interest include, but are not limited to: orthopedic surgery, such as fracture repair, bone remodeling, and the like; sports medical applications, such as ligament repair, cartilage removal, and the like; neurosurgical applications, and the like.

The inventive device can provide variable tactile feedback to the operator depending on the tissue type. For example, in embodiments where the distal structure, such as a tissue modifier (e.g., an RF electrode), is linearly translated by a mechanical linear actuator (e.g., as described above), the operator may experience different haptic properties depending on the type of tissue the linearly translating distal structure is contacting. These different tactile properties can then be used by the user to distinguish tissue types. In other words, the device of the present invention may provide different sensations to an operator, such as a surgeon, depending on the nature of the tissue with which the distal end of the device is in contact during use. Likewise, the devices and methods of the present invention may also be used in tissue discrimination applications where the devices are used to determine specific properties of internal tissue that the distal end of the device contacts, such as whether the distal end of the device contacts soft tissue, cartilage, and the like.

As described above, in some embodiments, synchronization of the modulation waveform of the tissue modifier with its linear translation waveform provides additional benefits. For example, as the tissue modifier approaches the proximal limit, rapid withdrawal of the electrode from the hard tissue it encounters will physically separate the tissue modifier from the hard tissue by a gap. In some embodiments, the tissue modifier tip is actuated only when the tissue modifier is at or near the proximal limit position, as described above. This has the effect of preferentially transmitting tissue-altering energy to soft, compliant tissue as compared to firm, hard tissue. It is further stated that this provides for tissue discrimination based on elastic modulus. In the case of spinal surgical applications requiring removal of nuclear material, such as fusion, artificial total disc replacement, and artificial partial disc replacement, the synchronization of the modulation waveform with the linear translation waveform facilitates the delivery of tissue altering energy to the nucleus pulposus (soft compliant tissue) while minimizing the delivery of tissue altering energy to the annulus fibrosus (hard, firm tissue) of the intervertebral disc and the endplates of the vertebral body (hard, firm tissue). In addition, the cyclic linear translation of the tissue modifier helps prevent conditions in which the electrodes adhere to the tissue as they resect the tissue, resulting in increased thermal effects on the surrounding tissue, ineffective or discontinuous tissue dissection, accumulation of carbonized or otherwise modified tissue on the tissue modifier tip, or combinations thereof. In addition, the cyclic linear translation of the tissue modifier helps to cut the dissected tissue into smaller pieces, thus facilitating aspiration of the dissected tissue.

External member

Kits for practicing the subject methods are also provided, wherein the kits can include one or more of the above-described devices, and/or components of the subject systems, as described above. The kit may also include other components that may be used to implement the subject methods, such as guide wires, access devices, fluid sources, and the like. The various components may be packaged as desired, e.g., together or separately.

In addition to the components described above, the subject kits can also include instructions for using the kit components to perform the subject methods. The instructions for carrying out the subject methods are typically recorded on a suitable recording medium. For example, the instructions may be printed on a substrate such as paper or plastic. Likewise, these instructions may be present as package instructions within the kit, within the kit container label or within a component thereof (i.e., associated with the package or sub-package), etc. In other embodiments, the instructions reside as an electronic storage data file on a suitable computer-readable storage medium such as a CD-ROM, magnetic disk, or the like. In still other embodiments, the actual instructions are not present within the kit, but provide a means for obtaining the instructions from a remote instruction source, e.g., via a network. An example of such an embodiment is a kit comprising a web address where the instructions can be viewed and/or downloaded. As with the instructions, the means for obtaining the instructions is recorded on a suitable substrate.

Although the foregoing invention has been described in some detail by way of illustration and example for purposes of clarity of understanding, it will be readily apparent to those of ordinary skill in the art in light of the teachings of this invention that certain changes and modifications may be made thereto without departing from the spirit or scope of the appended claims. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting, since the scope of the present invention will be limited only by the appended claims.

Accordingly, the foregoing merely illustrates the principles of the invention. It will thus be appreciated that those skilled in the art will be able to devise various arrangements that, although not explicitly described or shown herein, embody the principles of the invention and are included within its spirit and scope. Furthermore, all examples and conditional language recited herein are principally intended expressly to aid the reader in understanding the principles of the invention and the concepts contributed by the inventor to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions. Moreover, all statements herein reciting principles, aspects, and embodiments of the invention, as well as specific examples thereof, are intended to encompass both structural and functional equivalents thereof. Further, such equivalents are intended to include both currently known equivalents as well as equivalents developed in the future, i.e., any elements developed that perform the same function, regardless of structure. Accordingly, the scope of the present invention is not intended to be limited to the exemplary embodiments shown and described herein. Rather, the scope and spirit of the present invention is embodied by the appended claims.

Claims (28)

1. A tissue modification device comprising:

an elongated member having a distal end sized to pass through a minimally invasive body opening, wherein the distal end includes an integrated visualization sensor and a tissue modifier.

2. The tissue modification device of claim 1, wherein the integrated visualization sensor comprises a lens and an integrated circuit.

3. The tissue modification apparatus of claim 2, wherein the visualization sensor is a CMOS device.

4. The tissue modification device of claim 2, wherein the visualization sensor is a CCD device.

5. The tissue modification device of claim 1, wherein the device further comprises an integrated articulation mechanism that provides steering capability for at least one of the visualization sensor, the tissue modifier, and the distal end of the elongate member.

6. The tissue modification device of claim 1, wherein the distal end of the elongate member is sized to pass through Kambin's triangle.

7. The tissue modification device of claim 6, wherein the distal end of the elongate member has an outer diameter of 7.5mm or less.

8. The tissue modification device of claim 7, wherein the distal end of the elongate member has an outer diameter of 7.0mm or less.

9. The tissue modification device of claim 8, wherein the distal end of the elongate member has an outer diameter of 5.0mm or less.

10. The tissue modification apparatus of claim 1, wherein the distal end of the elongate member further comprises an integrated illuminator.

11. The tissue modification apparatus of claim 10, wherein the illuminator is a fiber-optic illuminator.

12. The tissue modification apparatus of claim 10, wherein the illuminator is a light emitting diode.

13. The tissue modification device of claim 1, wherein the tissue modifier comprises an electrode.

14. The tissue modification device of claim 1, wherein at least one of the visualization sensor and the tissue modifier is movable relative to the distal end of the elongate member.

15. The tissue modification apparatus of claim 1, wherein the distal end of the elongate member further comprises an irrigator and an aspirator.

16. The tissue modification device of claim 15, wherein the aspirator is located proximal to the integrated visualization sensor.

17. The tissue modification device of claim 15, wherein the aspirator includes a port having a cross-sectional area that is 33% or greater of a cross-sectional area of the distal end of the elongate member.

18. The tissue modification apparatus of claim 1, wherein the elongate member is rigid.

19. The tissue modification device of claim 1, wherein the tissue modification device is configured to modify intervertebral disc tissue.

20. The tissue modification device of claim 1, wherein the device is configured to be disposable.

21. The tissue modification apparatus of claim 1, wherein the apparatus includes a handle at a proximal end.

22. The tissue modification apparatus of claim 21, wherein the distal end of the elongate member is rotatable about its longitudinal axis when a substantial portion of the lever is held in a fixed position.

23. A system, comprising:

(a) an elongated member having a distal end sized to pass through a minimally invasive body opening, wherein the distal end includes an integrated visualization sensor and a tissue modifier; and

(b) an external controller operatively coupled to the proximal end of the elongated member.

24. The system of claim 23, wherein the system further comprises an image display for displaying images obtained by the visualization sensor to a user.

25. The system of claim 23, wherein the system further comprises a minimally invasive access tube.

26. A method of altering an internal target organization of a subject, the method comprising:

(a) positioning a distal end of a tissue modification device, the tissue modification device comprising an elongated member having a distal end sized to pass through a minimally invasive body opening, wherein the distal end comprises an integrated visualization sensor and a tissue modifier operatively associated with the internal target tissue; and

(b) altering the internal target tissue with the tissue modifier.

27. The method of claim 26, wherein the internal target tissue comprises spinal tissue.

28. The method of claim 26, wherein the method is a method of removing nucleus pulposus tissue from an intervertebral disc.