CN111699017A - Cochlear implant positioning system - Google Patents

Abstract

A navigation system or combination of navigation systems may be used to provide one or more navigation modalities for tracking position and navigating individual instruments in a volume. For example, both electromagnetic (EM) navigation systems and electrode potential (EP) navigation systems may be used to navigate instruments within the volume. Two navigation systems may each be used to selectively navigate the individual instruments in the volume individually. Also disclosed are systems and processes for determining the shape of the individual instruments, alone or in combination with the positions of the instruments. The instrument can be navigated by adding tracking means or through native or inherent parts of the instrument.

Description

Cochlear Implant Positioning System

CROSS-REFERENCE TO RELATED APPLICATIONS

This application contains information related to US Patent Application No. 15/890,920 entitled "COCHLEAR IMPLANT LOCALIZATION SYSTEM" and US Patent Application No. 15 entitled "COCHLEAR IMPLANT LOCALIZATION SYSTEM" The subject matter disclosed in /890,949. The entire disclosures of each of the aforementioned applications are incorporated herein by reference.

technical field

The present disclosure relates generally to a system for locating a tracked item, and more particularly, to a locating system that uses one or more modalities to locate an item within a volume.

Background technique

This section provides background information related to the present disclosure which is not necessarily prior art.

The navigation system can be used to track and navigate instruments within the volume. For example, navigation systems can be used to track electromagnetic tracking devices on instruments during surgical procedures. A tracking device is positioned for determining the positioning of the instrument.

However, some instruments are not associated with a tracking device. Therefore, some instruments cannot be tracked with a navigation system. Untraceable instruments may require direct inspection to determine final positioning. Furthermore, due to various limitations, it may be difficult to associate tracking hardware with such instruments.

SUMMARY OF THE INVENTION

This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features.

和/或

耳蜗植入物。耳蜗植入物可以包含沿可植入装置的长度间隔开的多个电极。因此，可植入装置可以是植入物。植入物可以出于各种目的(如接收、放大和/或提供刺激)而被连接到外部装置。用于接收音频信号并且在耳蜗内提供刺激以复制听觉的耳蜗植入物的手术对于所属领域的技术人员来说是众所周知的。A navigation system or combination of navigation systems may be used to provide navigation for tracking the instrument. The instrument may be an instrument that aids in performing surgery and/or may be a permanently implanted device. Permanently implantable devices may include well-known devices, such as cochlear implants, including Contour sold by Cochlear Americas, having a place of business in Centennial, CO, USA

and / or

Cochlear Implants. A cochlear implant may contain a plurality of electrodes spaced apart along the length of the implantable device. Thus, the implantable device may be an implant. Implants can be connected to external devices for various purposes, such as receiving, amplifying, and/or providing stimulation. Procedures for cochlear implants to receive audio signals and provide stimulation within the cochlea to replicate hearing are well known to those skilled in the art.

A navigation system may contain one or more types of navigation or navigation modalities to navigate a single instrument. A single instrument can be placed in the patient and tracked. For example, both electromagnetic (EM) tracking systems and electrode potential (EP) tracking systems can be used to navigate instruments within a patient. Various EM navigation systems include the EM navigation systems disclosed in US Pat. Nos. 7,599,730 and 7,697,972, both of which are incorporated herein by reference. Various EP navigation systems include the EP navigation systems disclosed in US Pat. Nos. 8,260,395 and 9,101,285, both of which are incorporated herein by reference. Certain navigation systems may operate in combination with and/or using both types of navigation modalities (eg, both EM and EP), and include the navigation modalities disclosed in US Pat. Nos. 8,494,613 and 8,494,614. state.

Navigation systems can often contain locators and tracking devices. Those skilled in the art will understand that the locator can transmit or receive signals, and the tracking device can also transmit or receive signals to allow the location of the tracking device associated with the surgical instrument to be determined. The surgical instrument may have associated therewith one or more tracking devices for navigation, as discussed herein. Furthermore, each tracking device may be used for one or more navigation modalities. For example, an instrument can contain electrodes that can be used with an EP tracking system and that can also be associated or moved relative to a tracking device containing an EM coil to be used with the EM tracking system.

An instrument may contain one or more tracking devices for use with one or more navigation systems during a single procedure. Additionally, one method can be used to register two navigation systems during a single procedure. Registration of the two navigation systems may allow all or a selected number of points in one navigation domain to be determined to coordinate or correspond to all or a selected number of points in a second navigation domain.

The apparatus may also include one or more tracking devices that may be used with a single selected navigation system of a single selected modality. In various embodiments, portions of the instrument, including the implant, may be used as tracking devices during implantation procedures. After implantation, the same portion can be reused as an augmentation portion or reassigned as an augmentation portion.

It should be understood that although the following disclosure specifically refers to cochlear implants, other types of implants may also be used. As discussed herein, cochlear implants contain various parts that can be used for navigation purposes during an implantation procedure but can be repurposed to stimulate a patient after implantation. In other words, a cochlear implant may have parts (eg electrodes) that operate in a first function and then be changed to a different function. A cochlear implant may contain multiple electrodes connected for use to a receiver and stimulator (R&S). During use after implantation, the R&S can receive the signals and provide stimulation signals to the electrodes. The electrodes can be used for tracking prior to implantation so that no changes or additions to the implant's hardware are required. Thus, the standard structure of the cochlear implant can be maintained. However, as discussed herein, various additional tracking devices may be added to the cochlear implant.

Furthermore, it should be understood that the systems and methods disclosed herein are not limited to use during implantation in the human body, but may also be used during navigation of the instrument relative to any non-living machine having selected or suitable features.

Other areas of application will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only, and are not intended to limit the scope of the disclosure.

Description of drawings

The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.

Figure 1 is an environmental view of a navigation system;

Figure 2A is a detailed view of a subject and a portion of a localizer according to various embodiments;

2B is a detailed cross-sectional view of a subject in accordance with various embodiments;

Figure 3 is a detailed view of an instrument according to various embodiments;

4 is an environmental view of the device during implantation in a subject according to various embodiments;

Figure 5 is a detailed view of an instrument according to various embodiments;

FIG. 6 is a detailed environmental view of the apparatus according to various embodiments;

7, 7A and 7B are flowcharts illustrating a method of determining the shape of an implantable device and subroutines thereof;

Figures 7A1 and 7A2 illustrate theoretical shapes based on capacitance between multiple electrodes; and

8 is a perspective view of an implantable device according to various embodiments.

Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.

Detailed ways

Example embodiments will now be described more fully with reference to the accompanying drawings.

Fig. 1 shows a navigation system 20, which may be a surgical navigation system, and is shown in further detail in Fig. 2A. The first tracking system may include an electrode potential (EP) tracking system 22 . The second tracking system may include an electromagnetic (EM) tracking system 24 . Suitable EP tracking systems may include the EP tracking systems disclosed in US Pat. Nos. 8,260,395 and 9,101,285, both of which are incorporated herein by reference. Suitable EM navigation systems include the EM navigation systems disclosed in US Pat. Nos. 7,599,730 and 7,697,972, both of which are incorporated herein by reference. The first tracking system 22 and the second tracking system 24 may be used to track one or more instruments, such as a single surgical instrument 26 . The surgical instrument 26 may be any suitable instrument, including a cochlear implant positioned in the cochlea of the inner ear of the subject. Other suitable devices may also include, but are not limited to, cardiac electrode implants, brain electrode implants, spinal electrode implants, sacral electrode implants, vagus nerve electrode implants, and gastric electrode implants, such as with Lead wires that act as part of an implantable medical device (IMD) for cardiac rhythm therapy, neurological therapy, ablation, or other suitable purposes.

The navigation system 20 may operate with only a single of the tracking systems 22, 24, each provided in a selected individual modality. The first tracking system 22 is an EP modal tracking system, and the second tracking system 24 is an EM modal tracking system. Thus, the navigation system 20 may be a single-modal or multi-modal tracking system.

In some procedures, it may be useful to have two tracking systems. An exemplary procedure involves placing a cochlear implant with one or more electrodes in the cochlea of a subject, such as a human subject or patient 36 . In the cochlea, electrodes on the implant can be exposed to conductive fluid for position determination using the EP tracking system 22 . Also, tracking devices that can transmit or receive EM signals can be tracked using the EM tracking system 24 . Furthermore, registration of the EM tracking system 24 with the image data may be used to help illustrate the location (eg, anatomical location or anatomy) relative to the patient 36 .

Certain procedures may also be more easily tracked using the EP tracking system 22 as opposed to the EM tracking system 24 . For example, a stylet containing an EM tracking device can be positioned through at least a portion of the implant or the delivery portion of the implant. However, in various procedures, the stylet can be removed from a portion of the implant to allow the implant to be substantially less rigid and more flexible. Once the stylet is removed from the implant, the precise location of the implant may not be tracked using the EM tracking system 24 . After the probe is removed, the implant electrodes can be tracked using the EP tracking system 22 .

成像系统、磁共振成像(MRI)系统和正电子发射断层扫描(PET)成像系统。外科医生34可以使用成像系统30在手术之前(术前)、手术期间(术中)或手术之后(术后)对患者36进行成像。对患者36进行成像可以创建可以在显示装置38或显示装置40上被视为图像84的图像数据。显示装置38、40可以单独提供，如在支架42上，或者作为工作站或处理系统44的一部分与处理系统一起提供。图像数据可以通过发射系统数据46(如有线或无线发射系统)从成像系统30传送到显示装置38、40。可以为选定手术选择图像并且图像可以适合于选定过程，如用于耳蜗植入物的内耳或耳蜗的图像。In addition to the tracking systems 22 , 24 , the navigation system 20 used in the various procedures discussed above or herein may also include various components, such as an imaging system 30 . Imaging system 30 may be any suitable imaging system, and is illustratively shown as a fluoroscopic C-arm system 32 . Other imaging systems may include computed tomography (CT) imaging systems,

Imaging Systems, Magnetic Resonance Imaging (MRI) Systems, and Positron Emission Tomography (PET) Imaging Systems. Surgeon 34 may use imaging system 30 to image patient 36 before surgery (pre-operative), during surgery (intra-operative), or after surgery (post-operative). Imaging patient 36 may create image data that may be viewed as image 84 on display device 38 or display device 40 . The display devices 38 , 40 may be provided separately, such as on a stand 42 , or provided with the processing system as part of a workstation or processing system 44 . Image data may be transmitted from the imaging system 30 to the display devices 38, 40 via transmission system data 46, such as a wired or wireless transmission system. The images may be selected for the selected procedure and may be suitable for the selected procedure, such as images of the inner ear or cochlea for cochlear implants.

The navigation system 20 (which also includes the tracking systems 22 , 24 ) may be incorporated or connected to the processor system 44 . The processor system 44 may include a human input device, such as a keyboard 48, a joystick or mouse 50, a foot pedal 52, or any other suitable human input device. Each of the human input devices 48-52 may be connected to the processor system 44 or other systems (eg, imaging system 30) to control or actuate the same. The processor system may further include a general-purpose processor 44a configured to execute instructions stored on memory 44b (eg, non-transitory memory (eg, solid state memory, spinning hard disk, optically readable disk)). Processor 44a may also be a special purpose processor, such as an ASIC.

The EP tracking system 22 may contain components that generate electrical current within the patient 36 . The EP tracking system may comprise or be based on the Localisa ^™ intracardiac tracking system sold by Medtronic, Inc., having a place of business in Minneapolis, Minnesota. The EP tracking system 22 may also include portions disclosed in US Patent Nos. 5,697,377 or 5,983,126 to Wittkampf, which are incorporated herein by reference.

Briefly, the EP tracking system 22 may include one or more shaft electrodes 60 (including 60a, 60b, 60c). In various embodiments, the shaft electrodes may operate as shaft electrode pairs. Shaft electrode 60, which may also be referred to as a positioner, is operable to generate or inject electrical current within a volume such as patient 36. However, the shaft electrode 60 may contain a single shaft electrode 60a. However, it should be understood that two or more shaft electrodes 60b and 60c may also be provided. Because there are two or more electrodes, the temporal variation of the injected current can be used to more finely discern the positioning of the implantable device, as discussed further herein.

It should also be understood that one or more pairs of shaft electrodes may be provided. For example, three pairs of axis electrodes may be used to generate three substantially orthogonal current axes within the patient 36 . As described above, the shaft may be confined between selected pairs of shaft electrodes by alternating current generated between any pair of shaft electrodes. For example, a first pair of shaft electrodes may be positioned to the left and right of the patient 36 to define the X-axis when current is generated between the two shaft electrodes.

The location of the tracking device 70 may be determined or calculated using the injected current from one or more shaft electrodes. The tracking device 70 may comprise a first or EP tracking device 70a and a second or EM tracking device 70b. The EP tracking system 22 may be used to track the EP tracking device 70a. The first tracking device 70a may sense the voltage or associated impedance within the patient 36 based on the induced current from the shaft electrode 60a or between shaft electrode pairs. The voltage may be related to the position of the first tracking device 70a within the patient 36 .

The shaft electrodes 60a-60c may be driven by generators in the controller 72, which are wired or wirelessly connected to the shaft electrodes 60a-64b. The generator may provide power for generating a selected electrical current (eg, alternating current within the patient 36). Controller 72 may also contain connections for instrument 26 to transmit signals from tracking device 70 to controller 72 . According to various embodiments, the connection to the instrument 26 may be wired or wireless. Additionally, the controller 72 may contain a processor portion, or the controller may simply be a transmitter for transmitting signals from the tracking device 70 . Signals may be transmitted from controller 72 to processor system 44 via transmission system 74 . Transmission system 74 may be a wired or wireless transmission system.

The EM tracking system 24 may also be associated with the controller 72, or may be provided with a separate controller system. It will be appreciated that various separate circuitry portions may be provided in the controller 72 to generate or operate the EP tracking system 22 or the EM tracking system 24 .

The EM tracking system 24 includes an EM localizer 76 that can be positioned relative to the patient 36 . The EM tracking system may include the AxiEM ^™ electromagnetic tracking system sold by Medtronic Navigation, Inc., having a place of business in Colorado, USA. The localizer 76 may generate an electromagnetic field that is sensed by the EM tracking device 70b. Alternatively, the EM tracking device 70b may generate the field sensed by the localizer 76 .

The locator may be used as part of a tracking system for determining the location of the tracking device 70 . For example, the locator 76 may be interconnected with the controller 72 to transmit a signal to the processor system 44 regarding the location of the EM tracking device 70b. The shaft electrodes 60a-60c may be localizers that induce a current shaft within the patient 36 to locate the EP tracking device 70a. Thus, a locator may refer to a portion of a tracking system that may be external or internal to a volume (eg, patient 36 ) used to determine the location of tracking device 70 .

According to various embodiments, a localizer device including EM localizer 76 and shaft electrodes 60a-60c may be used to define a navigation domain in subject space. Subject space may refer to the physical space in which the instrument moves during a selected procedure. The subject space may contain the patient space of the patient 36 . The patient space may be the physical space in which surgery is performed during surgery. The patient space may also contain a navigation space through which surgical instruments 26 are navigated. The image space may be defined by image data displayed as images 84 on the display devices 38 , 40 . The image data may comprise any suitable image data, such as image data of the skull, inner ear, or other suitable portion of the patient 36 . The image data is used to generate or present the images 84 displayed on the display devices 38, 40, and may also include atlas data. Graph data can contain statistical or historical data. The atlas data can be registered or deformed into patient image data or patient space. It will be appreciated that the atlas data can be used in an imageless navigation system. For example, an imageless navigation system may not need to acquire image data of the patient 36 . Image data and map data may be stored in or recalled from memory 44b.

The patient space may be registered to the image space of the image data to allow the position of the instrument to be displayed (eg, superimposed on the image 84 as an icon) according to any suitable technique, including those discussed herein. Typically, however, the patient space is registered to the image data to allow icons or representations of tracked devices (eg, surgical instruments 26 ) to be displayed or superimposed on top of the images 84 on the display devices 38 , 40 . Registration typically allows for the transformation of image data into patient space. Various registration techniques may include contour matching, fiducial or point matching, automatic registration, or any other suitable registration. For example, various landmarks or fiducials may be identified in the image data and/or image 84, and the same fiducials or landmarks may be identified within the patient 36 (eg, in the inner ear). The image data can then be transformed into the patient space of the patient 36 so that the appropriate location of the superimposed icon 26i can be displayed relative to the image 84 . The registration techniques may include the registration techniques discussed in the above-incorporated US patents.

Additionally, as discussed herein, the EP tracking system 22 may be registered to the EM tracking system 24 . Registering the EP tracking system 22 to the EM tracking system 24 may allow the image data 80 to be used to navigate the EP tracking device 70a. For example, EP tracking system 22 may not form positioning geometry that is Euclidean to effectively map to the Euclidean coordinates of the image of subject 36 . Thus, mapping points or co-correlation points between the EM tracking system 24 and the EP tracking system 22 allow the points determined in the EP tracking system 22 to be translated to the EM tracking system 24 , and thus to the image 84 . In various embodiments, co-registration may include locating EM tracking devices trackable using EM tracking system 24 with EP tracking devices trackable by EP tracking system 22 . Co-location (eg, placing the EM tracking device and the EP tracking device at the same location) may allow tracking of a point in space using both the EP tracking system 22 and the EM tracking system 24 to allow registration (ie, translation of the two navigation spaces) ).

Instrument 26 may include a cochlear implantable member or cochlear implant electrode assembly 226 to be placed in patient 36 . In various embodiments, as shown in FIGS. 2B and 3 , the cochlear implant 226 may include an elongated body 230 extending along a long axis. The elongated body 230 may contain a plurality of implant electrodes or contacts, such as twenty-four individual electrode segments or contacts (also individually referred to as electrodes) 232i configured to be positioned within the subject's cochlea 37 to 232xxiv. It should be understood that the cochlear implant 226 may contain any suitable number of electrodes 232, and that twenty-four electrodes are merely exemplary. Also, as discussed herein, cochlear implant 226 may also be referred to as an array or assembly of electrode contacts that may contact the cochlea to emit or deliver stimulation signals from a stimulator or source.

One or more of electrodes 232 may be formed as solid plates or members (eg, biocompatible conductive plates (eg, stainless steel, gold, etc.)) having a thickness extending from the long axis of body 230 . The electrodes may also or alternatively be formed as coils of conductive material (eg, copper, gold, carbon, etc.). The coils may be formed around a core (eg, an air core), and the core may extend along an axis generally angled and/or perpendicular to the long axis of the body 320 . In various embodiments, at least a selected number of electrodes (which may include all electrodes) may be formed as solid plates, while other electrodes may be formed as coils or lengths of wire. If the electrodes are formed as coils of conductive material, the coils may be formed to have a geometry similar to a pole plate as shown in FIG. 3 , thus forming the coils on the sides of the implantable member 226 or arc surface. Thus, when a coil is provided as electrode 232, the outermost portion of the coil can contact the subject.

Each of electrodes 232 may be connected to selected portions by one or more connectors, communication or transmission lines, or cables 233. Each of electrodes 232 may have a separate wire or connection 233 that allows each of electrodes 232 to be directly connected (eg, wired) to an internal receiver as shown in Figure 2A and stimulator (R&S) 234 and/or directly connected to an external R&S 234a as discussed herein. Accordingly, implant 226 may deliver stimulation from R&S 234, 234a to selected portions of subject 36 and/or transmit or receive other selected signals as discussed herein.

Profile和/或Cochlear^TM

声音处理器中所包含的接收器和刺激器部分以及各种特征。接收器可以接收外部刺激，并且通过一个或多个电连接器233向电极232中的一个或多个选定电极提供电刺激。连接器233可以是导电的，并且可以包含导电导线或其它导电材料。The R&S 234, 234a may be connected to the cochlear implant 226 at selected times to provide stimulation within the cochlea 37, as is known in the art. Thus, the cochlear implant may be connected to the R&S 234 as shown by the dashed portion 226'. The R&S 234, 234a may comprise any suitable R&S, such as the implantable Modiolar Electrode (CI532) sold by Cochlear Ltd. having a place of business in Centennial, Colorado Cochlear ^TM Electrode System

Profile and/or Cochlear ^TM

The receiver and stimulator parts and various features included in the sound processor. The receiver may receive external stimulation and provide electrical stimulation to one or more selected ones of electrodes 232 through one or more electrical connectors 233 . Connector 233 may be conductive, and may contain conductive wires or other conductive materials.

The R&S 234 may include an internal R&S 234 (as shown in Figure 2A) and/or an external R&S 234a. The external R&S 234a may be substantially the same as the internal R&S 234, or contain selected additional or alternative components. In various embodiments, the external R&S 234a may contain a portion that allows transdermal communication with an internal receiver (eg, the internal R&S 234). The inner portion may then transmit signals via the connector 233 to eg the implantable electrode 226 along the communication line 226' in the manner discussed above. Thus, the R&S 234 may contain an inner part 234 and an outer R&S part 234a. It should be understood that the external part 234a may contain most or all of the power supply, processor part and hearing or signal receiving part and transmitters to the internal R&S 234. The external assembly may contain parts as described and those further described in US Patent 4,352,960, which is incorporated herein by reference. Additionally, the external components may contain various additional transmission features, such as transmitting signals to the CACs 22 , 24 , eg, to aid in the navigation and placement of the implant portion 226 .

By providing stimulation to electrodes 232, external sound may be provided to subject 36 as stimulation in an appropriate manner. As shown in Figures 2B and 4, during implantation, cochlear implant 226 may be positioned in cochlea 37 of subject 36 through small opening 36o. The cochlear implant 226 may be flexible in a suitable manner to be positioned within the cochlea 37 to achieve the shape of the interior space of the cochlea 37 (including circular or interior wrap). Accordingly, the cochlear implant 226 may contain a selected degree of flexibility to allow implantation into the cochlea 37 .

Opening 36o may contain a smaller surgical opening that is only slightly larger than the diameter of cochlear implant 226 . For example, the outer largest diameter of the cochlear implant 226 may be about 0.1 millimeters (mm) to about 2 mm, including about 0.8 mm to about 0.1 mm, further including about 0.5 mm to about 0.2 mm. Additionally, the portion of the cochlear implant 226 containing the electrodes 232 may taper from the largest dimension to about 0.4 mm to about 0.8 mm. The inner diameter of opening 36o may thus be about 0.1 millimeters to about 0.8 millimeters larger than the diameter of cochlear implant 226 . In various embodiments, the inner diameter of opening 36o may be about 1% to about 300% larger, including about 150%, than the outer diameter of cochlear implant 226 . Thus, when cochlear implant 226 is placed into cochlea 37, the size of opening 36o may not allow direct viewing of the cochlear implant.

As discussed above, the navigation system 20 may allow for tracking of selected portions of the cochlear implant 226 . For example, the EM tracking device 250 may be positioned at the distal end 254 of the cochlear implant 226 . EM tracking device 250 may be any suitable EM tracking device, such as an EM tracking device that includes one or more coils or wires made of conductive material. For example, EM tracking device 250 may contain three coils of wire, all on different axes, but with a common origin. EM tracking devices can be designed and configured to allow six degrees of freedom position (including position and orientation) to be determined. Exemplary EM tracking devices include the EM tracking devices disclosed in US Patent No. 8,644,907, which is incorporated herein by reference.

The EM tracking device 250 may be tracked by the EM tracking system 24 . As discussed above, EM tracking system 24 may include a localizer 76 for transmitting or receiving EM fields to allow determination of EM tracking devices 70b (which may include one or more of the tracking devices 250). The tracking device 250 may be sized and configured to be positioned within the internal structure while allowing tracking of the cochlear implant 226 and/or without altering the known external geometry of the cochlear implant 226 .

Furthermore, it should be understood that multiple devices 250 may be positioned along the length of the cochlear implant 226 . For example, the plurality of devices 250 may be positioned along the length of the cochlear implant 226 spaced from about 0.1 millimeters (mm) to about 1 centimeter, inclusive. The tracking devices may be spaced apart along the body 230 , such as along the longitudinal axis of the body 230 . For example, each of the plurality of these devices 250 may be positioned substantially adjacent to each of the electrodes 232 along the length of the body 230 . Thus, a defined or substantially precise location of the length of the body 230 of the cochlear implant 226 can be determined. Additionally, the tracked and determined position of the cochlear implant 226 may be shown relative to the image 84 on the selected display device(s) 38 , 40 based on the registration of the image data to the patient 36 .

Thus, in various embodiments, the EM tracking device 250 or devices 250 may be formed in the body 230 of the cochlear implant 226 to allow tracking of one or more points along the length of the cochlear implant 226 . Tracking one or more of the devices 250 allows the location of the cochlear implant 226 to be determined. The determined position of the cochlear implant 226 may then be shown relative to the image 84 shown on the selected display device 38 , 40 . Tracking EM tracking devices 250 using EM tracking system 24 is well known in the art. As discussed above, the tracking device 250 may generate or sense an electromagnetic (EM) field when the locator 76 is operating in the opposite direction to the tracking device 250 . Signals from the locator 76 and/or the tracking device 250 are transmitted directly to the processor system 44 or through the CAC 72 to the processor system. The transmission of the signal may be wireless or wired, such as using the transmission line 76 ′ from the locator 76 and/or a suitable transmission system (wireless or wired) from the EM tracking device 250 . In various embodiments, the connector 236 of the cochlear implant 226 may be connected to the EM tracking system 24 (eg, the CAC 72 ) to transmit signals from the EM tracking device 250 .

The signals from the tracking device 250 are used to determine the position (including the three-dimensional positioning and one or more orientations in space of the tracking device 250 and thus the instrument 26). As described above, registration of the image data to the subject may be performed such that tracking of the cochlear implant 226 may allow the position of the cochlear implant relative to the image 84 to be shown.

With continued reference to Figures 2B, 3 and 4, the position of the body 230 of the cochlear implant 226 may be determined by a plurality of EM tracking devices 250, including a second EM tracking device 250' and a third EM tracking device 250". As described above It is noted that multiple tracking devices can be used to display or determine specific locations of multiple points along the length of body 230. Thus, specific shapes such as coiled shapes can be determined based on multiple spaced tracking devices. This will be used to determine implants The final positioning of the implant 226 and when the implant has reached the selected positioning.

Referring additionally to FIG. 5 , in addition to or alternatively to providing the EM tracking device 70b as one or more of the EM tracking devices 250 in the implanted member 226, the EM tracking device 70b may be provided as a temporary member or a removable member . In various embodiments, the cochlear implant 226 may be positioned within a sleeve or flexible member, such as a silicone or other selected flexible material sleeve 270 . The sleeve 270 may have a terminal end 272 that covers the end of the implant 226 . The sleeve 270 may further include openings or gaps 274, such as a first gap 274a and a second gap 274b. The gaps may be separated by solid portions 276 . Gap 274 allows electrode 232 to enter a portion of patient 36 , such as cochlea 37 . The cannula may be positioned over the implant 226 prior to positioning the cannula in the cochlea, as is well known in the art. In this case, the sleeve 270 may form part of the implant.

A traceable stylet or guidewire 280 can be positioned within cannula 270 and can extend a distance into cannula 270 (including extending to terminal end 272). Guidewire 280 may include one or more EM tracking devices 70b, such as tracking device 282' and/or multiple tracking devices 282". Tracking device 282 may include multiple tracking devices positioned along the length of guidewire 280. For example, tracking The devices 282 can be spaced apart along the longitudinal axis of the guidewire 280. Accordingly, the guidewire 280 can be positioned within the cannula 270 during implantation and positioning of the implantable member 226.

Once the final positioning of the implant 226 is achieved, the guide wire 280 can be removed. The cannula 270 may remain in place with the cochlear implant 226 when the guidewire 280 is removed. In various embodiments, the guidewire 280 may be removed at any time prior to achieving final implant positioning to allow the implantable member 226 to achieve a shape or position within the cochlea 37 . Because the guidewire 280 is removable, the tracking device 282 need not be permanently incorporated into the implantable member 226. Removal of the guide wire 280 also allows the cochlear implant 226 to remain unchanged from the current configuration, but allows at least a portion of the cochlear implant 226 to be tracked. However, maintaining the guidewire 280 with the implant while positioning the implant within the cochlea may allow the position of the implantable member 226 to be tracked during at least a portion of the implantation procedure.

Guidewire 280 may contain one or more tracking devices 282 . Tracking device 282 may comprise a tracking device formed around the exterior of guidewire 280 , such as having a plurality of coils of conductive material (eg, wires) around and equiaxed along the long axis of guidewire 280 . The coil may be formed of a conductive material (eg, wire) wrapped around the outer surface of the guidewire 280 . Additionally, the wire may be wrapped at selected angles to provide differentiation of the tracking axis relative to the longitudinal axis of the guide wire 280. The selected package configuration and trackable portion includes the package configuration and trackable portion disclosed in US Patent No. 8,644,907, which is incorporated herein by reference. The tracking member 282 may also or alternatively be surrounded by a perimeter of a size and shape to be positioned within the guidewire 280 (eg, about 0.1 mm to about 0.5 mm in diameter and about 0.5 mm to about 5.0 mm in length). Individual coils of wire wound around the core. The individual coils may be selectively placed within the guidewire 280 at selected locations, such as near the tip of the guidewire and/or along its length. Regardless of the tracking member 282 configuration, the trackable member 226 may be tracked using the tracking member to provide a determination of the location (including its shape) of various points of the trackable member 226 . However, the guidewire 280 may be removed from the cannula 270 prior to concluding the procedure on the patient 36 . By removing the guidewire, the implanted member 226 is configured to be positioned within the subject without permanently incorporating the tracking device 280 .

Alternatively or in addition to the EM tracking device 70b, the implantable body 226 may contain an outer sleeve 270, as discussed above. The cannula 270 discussed above and shown in FIG. 5 may be permanently implanted with the implantable device 226 . However, removable or tracking sheath 290 may be temporarily positioned over implantable device 226 and/or over sheath 270 . As shown in Figure 3, the tracking cannula 290 may contain one or more of the EM tracking devices 70b, such as a first EM tracking device 294' and a second tracking device 294". The EM tracking devices 294', 294" may A removable sleeve 290 is formed (eg, molded into the removable sleeve). Removable sleeve 290 may be formed with body 230 from a resilient material and/or including a material with a sufficiently high coefficient of friction. Thus, when the implantable device 226 is positioned and moved into the patient 36, the cannula 290 can be maintained in a selected position relative to the implantable device 226. However, once the implantable device 226 is selectively positioned within the cochlea, the removable sleeve 290 can be removed, such as through an open or frangible end.

Tracking devices 294', 294" may be used to track the position of cannula 290 as implantable portion 226 moves toward cochlea 37 to and through opening 36o. As cannula 290 moves with implantable portion 226 The position of the implantable portion 226 can also be determined. The implantable portion 226 can also be tracked using a cannula 290 formed of a material that remains substantially stationary relative to the implantable body 230, tracking devices 294', 294" in the cannula 290. into the location of the device 226. The cannula 290 may be formed of selected materials such as biocompatible silicone, or the like. The material of sleeve 290 may fixedly engage implantable device 226 for retention relative to implantable device 226 during an implantation procedure. Accordingly, the cannula 290 remains substantially stationary and movement relative to the implantable member 226 during implantation does not exceed the error tolerance of the tracking system 24 .

The tracking devices 294', 294" may be formed at discrete intervals along the length of the removable sleeve 290. Each of the tracking devices 294', 294" is made of a plurality of conductive materials used as the EM tracking device 70b the coil. For example, the coils may be formed on the surface of the sleeve 290 relative to each other. In various embodiments, the conductive material of the tracking devices 294' and 294" may be formed as windings around the exterior of the sleeve 290 along the longitudinal axis of the sleeve 290. As discussed above, the tracking devices 294', 294" may also be Formed or provided as small coils and/or printed on the sleeve, and/or formed as windings on the sleeve. Accordingly, the tracking devices 294', 294" may be formed substantially similar to those of the guide wire 280. It should be understood, however, that the tracking devices 294', 294" may be formed by positioning or forming on the surface or wall of the cannula 290. formed in separate and separate parts.

After positioning the implantable member 226 in the cochlea 37 , the sleeve 290 can be removed from the implantable device 226 . As shown in FIGS. 2B and 3 , tabs or pull straps 298 may be attached to the sleeve 290 and extend outwardly through the opening 36o to be grasped by the user or surgeon 34 . After positioning the implantable device 226 within the patient 36 , the pull strap 298 can be grasped and pulled to remove the sleeve 290 from the implantable device 226 . Cannula 290 may include a frangible or breakable portion, such as a perforated portion (eg, perforation 302 ), located at distal end 290 ′ of cannula 290 . The perforation 302 can be opened or perforated by pulling the pull strap 298 and the sleeve 290 at the perforation that engages the distal end 254 of the implantable device 226. When the implantable member 226 is engaged, the perforations can be opened to allow the cannula 290 to be withdrawn from over the implantable device 226 after the implantable device 226 is positioned in the cochlea 37 .

It should be appreciated that other features may be provided to remove sleeve 290 from implantable device 226 to ensure that sleeve 290 need not be maintained within subject 36 after implantable device 226 is positioned. For example, the terminal end can be open and the sleeve 290 can contain features such as a high coefficient of friction material to maintain the cannula 290 fixed relative to the cochlear implant 226 during implantation. However, it should be understood that the sleeve 290 may be maintained on the implantable device 226 during the useful life of the implantable device 226 . Cannula 290 may be formed from a similar biocompatible material as cannula 270 . Furthermore, it should be understood that the cannula 270 may contain the tracking devices 294', 294" rather than providing the removable cannula 290 as a separate second cannula.

According to various embodiments, wireless or wired transmission of signals to the EM tracking system 24 may be performed from each EM tracking device 70b. The EM tracking system 24 may receive the tracking signals to allow the location of the respective tracking device to be determined, and further to determine the location tracked by the instrument 26 (including the implantable device 226). Various parts of the implantable device 226 may be repurposed or re-tasked from tracking during implantation to during use of the implantable device 226 to stimulate the cochlea after implantation. For example, as discussed above, the implantable device 226 includes one or more leads 236 that may be interconnected to the plurality of electrodes 232 on the implantable device 226 . Before connecting lead 236 from cochlear implant 226 to a selected receiver and stimulator 234 that can be positioned with patient 36, a tracking signal from a corresponding tracking device can be transmitted along lead 236, as is typical for cochlear implants as known. Thus, lead 236 may be used both to transmit signals from the tracking device to EM tracking system 24 , and may be used to subsequently disconnect from EM tracking system 24 and connect to receiver and stimulator 234 for implant component 226 to operate. As noted above, one or both of the inner R&S section 234 and/or the outer R&S 234a may transmit signals from selected sections (eg, coils 250 and/or electrodes 232) for tracking. It should be appreciated that the coil 250 and/or the electrodes 232 may communicate via signals through the internal R&S section 234 and/or the external R&S 234a and or alternatively the connector 233.

In addition to and/or alternatively to EM tracking device 70b, EP tracking device 70a may be provided with implantable device 226, as discussed above. As discussed above, one or more shaft electrodes 60a - 60c may inject electrical current into subject 36 . The injected current may create a voltage or impedance at one or more electrodes on the implantable device 226 . For example, as discussed above, the implantable device 226 includes one or more electrodes 232, where the electrodes 232 may be implant electrodes that stimulate the cochlea 37 once connected to the R&S 234. Electrodes 232 may emit or transmit signals along conductive members or wires 233 . As discussed above, lead 233 may be connected to EP tracking system 22 in a manner similar to how EM tracking device 24 is connected. Thus, lead 233 may be initially designated or used as a transmission lead for tracking electrode 232, and may then be connected to stimulators and receivers for transmission and/or reception from receivers and/or stimulators associated with patient 36 Signal. Similarly, electrode 232 may initially be designated or used as EP tracking device 70a. After implantation, the electrodes and leads 233 may be reassigned or reused as analog electrodes for the cochlear implant system.

In EP tracking system 22, shaft electrodes 60a-60c, or any suitable number of shaft electrodes 60, may inject electrical current into subject 36. A voltage or impedance may be sensed at one or more electrodes 232 due to the injected current. Referring to FIGS. 2A , 2B, and additionally to FIG. 5 , implant member 226 may be positioned within cochlea 37 . Cochlea 37 may contain a conductive or partially conductive fluid to allow one or more of electrodes 232 to sense voltage from shaft electrode 60 based on the injected current. Although shaft electrodes 60a, 60b, and 60c are shown, it should be understood that more than three shaft electrodes may be provided.

Each shaft electrode may inject current (which may contain alternating current). The alternating current creates a voltage or potential at each of the electrodes 232 on the implant device 226 . Each of the shaft electrodes 60a-60c can inject current at a selected frequency, where each frequency can be different. Furthermore, there may be temporal/time differences between the injected currents from each of the shaft electrodes 60a-60c. In other words, the current injected with shaft electrodes 60a-60c may be time or frequency multiplexed or differentiated. Thus, the potential measured at each of electrodes 232 can be triangulated relative to all of the individual shaft electrodes 60a-60c. The relative position of each of the electrodes 232 to each other may be determined based on the spaced position of each of the shaft electrodes 60a-60c. This may allow the user 34 to operate the processor system 44 to determine the relative position of the implant device 226 during implantation. User 34 may view image 84 and the position determined by implant device 226 may be displayed on image 84 .

As discussed above, image 84 may be registered to implant device 226 . EP tracking system 24 may be registered to image 84 using suitable registration techniques, such as those discussed above. For example, EP tracking device 70a may be positioned at known landmarks within subject 36 to determine registration to image data by identifying landmarks on image 84 . Alternatively, or in addition, one or more of the EM tracking devices 70b may be positioned at the same or known location relative to the EP tracking device 70a to allow for the matching of the EP tracking device 70a and the EM tracking device 70b. , and thus to image 84 . Co-registration with EM tracking system 24 may be used to assist in registration to image 84 (including EP tracking system 22). For example, as discussed above, one or more of the EM tracking devices 70b may be co-located with one or more of the shaft electrodes 60a-60c. Thus, the location of the shaft electrodes 60a-60c of the EP tracking system 22 can be determined with the EM tracking system 24, and thus, the location of the EP tracking device 70a tracked using the EP tracking system 22 can translate its determined location to the EM tracking system twenty four.

Registering in this manner, the image 84 can be registered with the EM tracking system 24, which can contain substantially Euclidean geometry that an EP tracking system may not contain. As understood by those skilled in the art, an EP tracking system that includes current injected from shaft electrodes 60a-60c may not provide a pure Euclidean geometry for registration. It should be understood, however, that precise registration may not be required if user 34 chooses to simply identify and/or understand the relative positions of electrodes 232 relative to each other during the implantation procedure.

Additionally, one or more of the EM tracking devices 70b may be associated with one or more of the shaft electrodes 60a-60c. In various embodiments, as noted above, rather than using a single solid member (eg, a metal plate) as the electrode 232, a coil of wire or other conductive material may be used to form the electrode 232 . If a coiled wire is selected, the thickness of the wire may extend from the surface of the implant electrode 232 toward the central axis of the electrode 232. The outermost portion can be used as an electrode pad for the electrode implant 232 .

Coiled wires as electrodes can work as tracking device 70b with EM tracking system 24 . Accordingly, the positions of shaft electrodes 60a-60c can be tracked using EM tracking system 24. Electrode 232 may be positioned relative to shaft electrodes 60a-60c. Thus, this will allow the use of the EM tracking system 24 to determine the position of the electrode 232 relative to a position. Thus, if the EM tracking system 24 is registered to the image, the positions of the electrodes 232 may also be shown as icons on the image 84 .

By understanding the position of each of electrodes 232 relative to each other on implantable device 226, user 34 can understand the varying positions of implantable device 226. Thus, user 34 can understand and determine whether implantable device 226 is reaching a selected shape, such as a predetermined shape of cochlea 37 . Additionally, the user 34 may understand and evaluate the image 84 of the subject 36 prior to surgery to predetermine the final desired orientation and position of the implant device 226 . Thus, by determining the relative positions of electrodes 232 of implant device 226, user 34 can determine whether a preselected shape (including the positioning and/or orientation of implant device 26) has been achieved.

Each of the electrodes 232 on the implantable portion 226 may be used to receive a voltage at the electrode based on the injected current from the shaft electrodes 60a-60c. This information can be used to identify or determine the location and orientation of the implant device 226 . As described above, the selected particular shape of the implantable device 226 can be selected to help ensure that the implantable device 226 is reaching the shape of the cochlea 37 . To aid in determining the shape of implantable device 226, the relative capacitance between each of the electrodes 232 may be determined with or without determination of the positioning of implantable device 226 relative to subject 36. As discussed herein, any first electrode and any second electrode of electrodes 232 may form any or selected electrode pairs. The capacitance between each arbitrary pair of electrodes 232 can be measured. A comparison of the capacitance between each arbitrary pair can be made instantaneously over time and at any instant in time to determine the relative distance between the arbitrary electrode pairs. It should be understood that the relative capacitance between any two of the electrodes of implant electrode 232 may also be determined by direct reading (eg, using a voltmeter) between the two electrodes (eg, 232i and 232ii). Therefore, no current needs to be injected from the shaft electrodes 60a-60c for the determination of the capacitance comparison.

Each of the shaft electrodes 60 a - 60 c positioned on the outer surface of the patient 36 may be used to generate an electrical potential relative to each of the electrodes 232 on the implantable device 226 . For example, shaft electrodes 60a-60c may be used to generate a relatively positive charge relative to electrode 232 on implantable device 226. Determination of the capacitance between any two of the electrodes 232 can be used to identify and determine the shape of the implantable device 226 between the two electrodes 232 . As the distance between the two corresponding electrodes decreases, the capacitance between the same two electrodes increases. For example, referring to FIG. 6, when implantable device 226 is substantially straight and initially inserted into patient 36, an initial distance between electrodes 232xxii and 232xxi may be achieved. As the implantable device 226 implements a coil within the cochlea 37, the distance between the two electrodes 232xxii and 232xxi may vary. As the two electrodes 232xxii and 232xxi get closer together, the capacitance between the two electrodes may increase as they begin to coil within the cochlea 37 . Thus, the capacitance between any two selected electrodes (especially between electrodes 232xxii and 232xxi) can be measured, and can be measured and compared over time to determine that the electrodes are getting closer to each other .

Capacitance may be determined between any two of the electrodes, and thus also between electrodes 232xxii may be determined relative to electrode 232xx and any other of electrodes to electrodes 232ii. Likewise, the change in capacitance over time between electrode 232xxii and all other electrodes can be measured and determined to help determine the shape of implantable device 226. Processor system 44 (including memory 44b) can maintain a record of capacitance changes over time, and can also determine the shape of implantable device 226 over time. The determined shape may then be shown on the display device 38 , 44 either alone or relative to the image 84 .

In addition to determining the capacitance between two of the electrodes 232 of the implantable device 226 by injecting current from the access electrodes 60a-60c as discussed above, direct determination or sensing may also be performed. As discussed above, connectors 233 connect portions of implantable device 226, such as each of electrodes 232, to the selected system. Connector 233 may connect to selected tracking systems 22 , 24 and/or workstation 44 . It should be appreciated that other suitable measurement systems may also be included within or associated with the various tracking systems 22, 24 and/or workstations 44. For example, a multimeter may be used to connect the multimeter directly to two or more of electrodes 232. By connecting a selected meter to two or more of the electrodes, a direct calculation of the difference in capacitance between two different electrodes can be determined. As discussed above, measurements may be taken between any or all pairs of electrodes 232 of implantable device 226 . Thus, it should be understood that the difference in capacitance between two of electrodes 232 need not be induced by shaft electrodes 60a-60c, but can be determined directly. In addition, the EM locator 76 can also be used to generate a field that can induce a voltage or capacitance difference between the electrodes 232 (which can also be measured using a selected system, such as a selected multimeter or other suitable meter).

It should be understood that each of the electrodes 232 on the implantable device 226 may measure relative to any other electrodes on the implantable device 226 . Thus, the number of possible electrode pairs is also a function of the number of electrodes on the implantable device 226 . Therefore, the greater the number of electrodes, the greater the number of possible pair measurements. The greater the number of electrode pairs, the higher the resolution in determining the shape of the implantable device 226.

As discussed above, the capacitance between various electrodes (eg, electrode 232 of implantable device 226) can be determined. An implantable device 226 comprising a selected number of electrodes 232 as noted above, or any suitable number of such electrodes, may be used to determine the shape of the implantable device 226 within a patient 36 or any suitable volume. The measurements may be based on shape determination algorithms and/or shape determination methods, as discussed below and as shown in flowchart 360 in FIG. 7 . To determine the shape of the implantable device 226, as noted above, the capacitance between selected electrode pairs can be determined and used to calculate the relative shape of the implantable device 226. It should be appreciated that the relative shape of the implantable device 226 may be relative to any selected fixed or known point (eg, tracked location) (eg, one or more of the tracking devices 250 associated with the implantable device 226 ). location of a tracking device). Accordingly, the shape of the implantable device 226 can be determined according to the method 360 shown in FIG. 7 and relative to a selected origin (eg, one or more of the tracking devices 250).

In various embodiments, method 360 begins at start block 364 and continues at block 368 to determine pairwise capacitances between selected electrodes 232 . In determining the pairwise capacitance between selected electrodes 232, it should be understood that the capacitance between any two of electrodes 232 may be determined. For example, the capacitance between electrodes 232i and 232ii may be determined as the capacitance between electrodes 232i and 232iii or 232i and 234iv. Accordingly, those skilled in the art will understand that the pairwise capacitance between selected electrodes may involve the determination of the capacitance between all possible electrode pairs of the implantable device 226 . Accordingly, the number of pairs selected may be based on the number of electrodes included in the implantable device 226 .

It should be further understood that the more times the pairwise capacitances are determined in block 368, the finer the determination of the shape of the implantable device 226 can be. For example, if a selected error or roughness of the shape to be determined by the implantable device 226 is chosen, then the pairwise calculations between each of the electrodes may be performed only on every other electrode or an appropriate number (as shown) half of the electrode, one third of the electrode, etc.) between the electrodes. If a finer shape determination is chosen, the pairwise capacitance between each electrode 232 and all other electrodes 232 can be measured and determined. However, pairwise capacitance determinations of electrodes may be made along the length of the implantable device 226 to determine the shape along the length of the implantable device 226 .

Once the pairwise capacitance measurements between the selected electrodes are completed in block 368 (from which the determination can be made), the calculated pairwise spacing is made in block 372 . The calculated pairwise spacing may be between any electrode pair for which the pairwise capacitance has been measured or determined in block 368 . For example, pairwise capacitances between all electrodes relative to each of the other electrodes may be performed in block 368 . In block 372 , a calculation of pairwise spacing may be performed based on the capacitance of the selected electrode determined from block 368 . The determination of pairwise intervals can be based on known computational or algorithmic techniques, such as direct computation, conformal transformations, helper functions, and numerical approximations. Typically, the pairwise separation may be the distance or radius (r) between the two electrodes (i) and (j). Thus, the determination of the radius (r) between the two electrodes can be shown or determined as r _ij . As discussed herein and shown in Figures 7A1 and 7A2, the radius r may define a circle with respect to the corresponding electrode.

The determination of the shape of the implant device 226 may be determined based on the pairwise spacing calculated from the measured pairwise capacitances. The determination of the shape of the implantable device 226 may be made by initializing the relative electrode positions in block 376 (also referred to as determining an initial or initial guessed position of the electrodes). Initialization of the relative electrode positions may be performed by selecting a source electrode such as electrode 232i. It should be understood that any suitable electrode may be selected as the source electrode, and that electrode 232i is merely exemplary. However, initialization does not require a single one of electrodes 232. Instead, the implant electrode assembly 226 can be assumed to be a straight line, and shape determination algorithms and methods as discussed herein can begin with this initialization.

Additionally, the shape of the implantable device 226 determined using the method 360 as shown in the flowchart of FIG. 7 may be used to calculate or determine a selected fine shape of the implantable device 226 . However, the relative or absolute position of implantable device 226 may be determined using an alternative or separate tracking device, such as tracking device 250 . Accordingly, the source electrode may be proximate to one or more of the tracking devices associated with or connected to the implantable device 226 .

With continued reference to Figure 7 and additional reference to Figure 7A, the initialization of the relative electrode positions in block 376 will be described in more detail. Figure 7A describes the process of block 376 in more detail. Accordingly, as shown in FIG. 7A , the method at 360 comprising block 376 comprises the sub-steps or sub-algorithms in block 376 . As discussed above, the selection or placement of a single electrode at the origin location _Pi is performed in block 380 . With continued reference to Figure 7A and additionally to Figures 7A1 and 7A2, the positions of the electrodes are shown in dots and enumerated by P _i or P _i+1 and P _i+N . It should be understood that any suitable number of electrodes 232 may be determined and that the following discussion of three electrodes is merely exemplary. Furthermore, it should be understood that, as discussed further herein, the electrodes may have an initial or initialized position determined as _Pi , and the relative position may then be determined.

Referring to Figure 7A1, the electrodes are shown in a straight line. It should be understood, however, that the electrodes may be positioned in any three-dimensional relative position, as shown in Figure 7A2. Furthermore, it should be understood that the location of the electrodes may be constrained by various constraints (eg, the subject's anatomy). Thus, the return or determined relative position of the electrodes may be based on or limited to constraints determined relative to the anatomy of subject 36 . For example, as shown in FIG. _7A2 , only one of the two orientations may be determined as much as possible and shown to the user 34, as the orientation of the branch to the right from the origin Pi is shown. For example, as shown in Figure 7A2, therefore, electrodes determined to be on the right (ie, P _i+N(r) ) can be determined as true or proper electrode locations, while electrodes determined to be on the left (ie, P i+N(r) ) That is, P _i+N(l) ) may be determined not to be a suitable or correct possible electrode location. Thus, as discussed further herein, only one of the selected possible positions of the electrodes may be determined or returned or shown to the user.

The distance between the electrodes (defined by the radius r, as noted above) can be based on the measured capacitance between the different electrodes. The measured capacitance may be based on the voltage applied across the implantable device 226 between the various electrodes and the implant system. As discussed above, the implantable device 226 includes a communication line 233 to the controller, which may be included in the processor system 44 . Thus, the capacitance between each of the electrodes can be measured and determined by the controller.

The distance or radius determined relative to each of the other electrodes, as shown in Figures 7A1 and 7A12. For example, electrode P _i includes a radius ri ₍₁₎ relative to the second electrode P _i+1 . Electrode _Pi also contains a radius ri ₍₂₎ relative to end electrode Pi _+N . Similarly, electrodes P _i+1 and P _i+N contain the radius relative to each of the other electrodes. It should be understood that only three electrodes are exemplary only, and to facilitate this discussion. As discussed further herein, the radius can be used to determine the relative position of the electrodes.

和

)以使得表1中的以下等式满足的方式放置。Once the selection of a single electrode at the origin is performed in block 380, the first nearest neighbor electrode may also be "placed". In placing the first nearest neighbor, it should be understood that the spacing is determined based on the measured capacitance between the selected electrode and said neighbor (here the first nearest neighbor). first nearest neighbor (where two electrodes are

and

) are placed in such a way that the following equations in Table 1 are satisfied.

Since the measurement error, instrument error or the amount of fitting is arbitrary, there may be errors in the amount, and the error is indicated by "ε". It should be further understood that, as discussed below, additional equations in a similar manner may be provided or derived to calculate the positions of all measured electrodes.

The implantable device 226 is positioned, or at least initially positioned within the patient, and the determination of the positions of the electrodes can help determine the shape of the implantable device 226 in the subject 36 . Thus, the method 360 aids in determining the position or shape of the implantable device 226 . Thus, in block 376, electrode placement and initiation of placement allow for the shape of the implantable device 226 to be determined. The placement or possible determination of the positioning of each of the electrodes may also contain a small amount of error, denoted ε. Thus, the calculated or checked position of the electrodes may be the radius between the electrodes, which contains some amount of error (eg, plus or minus (±)ε).

The position of the determined electrode can be between the origin or the first electrode P _i and any other electrode (eg electrode P _i+N ). The determining may then further include placing all neighbors or the kth nearest neighbor with less than or equal to k+1 nearest neighbor constraints in block 386 . As discussed above, the constraints may contain a certain amount of error to allow the placement of the electrodes relative to each other to be determined. The constraints may also include the location determined by the tracking device 70 . For example, the shape of the implantable device 226 may be limited or constrained by the location tracked and determined by any selected tracking device. Additional constraints may include selected or known rotational positions of the electrodes relative to the shape of the patient or subject space. For example, as shown in Figure 7A2, the electrodes may branch at selected locations (eg, in the right and left directions). Since the implantable device 226 is positioned in a selected portion of the patient 36 (eg, in the cochlea of the subject 36), the implantable device 226 may have selected or known curvilinear constraints. Thus, the constraints may only include return or placement electrodes that bend in a selected direction (to the right as shown in Figure 7A2). It should be understood that the curve may be any suitable curve or constrained shape and that the curve to the right is merely exemplary. Furthermore, it should be understood that the curve or branch locations may lie in three-dimensional space relative to any of the electrodes placed.

Finally, after all electrodes have been placed, the electrode relative positions can be returned in block 390 . Again, it should be understood that the relative positions returned may be the positions initialized in block 376 and that the detailed sub-algorithms or steps shown in FIG. 7A are included in the initialization of the relative electrode positions in block 376 . Furthermore, the placement of the electrodes is based on the capacitance between the electrodes measured and determined in pairs. As noted above, it should be understood that the position between electrodes or the distance between electrodes may be based on measurements of capacitance between all electrodes in pairs, or between a selected number of electrodes in pairs Measurement of capacitance. The placement of the electrodes may be based on the process as discussed above and shown in Figures 7A and 7A1 and 7A2. However, initialization of the relative electrode positions in block 376 may allow the shape of the implantable device 226 to be determined, as discussed further herein.

As discussed above, after initializing the electrode relative positions in block 376 , adjustments to the electrode relative positions may be made in block 396 . It should be understood that adjusting the relative position of block 396 is optional and not required for method 360 . However, the adjustment of the relative positions of the electrodes in block 396 may also include various sub-steps or algorithms, as shown and discussed in detail with reference to Figure 7B. The sub-steps shown and discussed with respect to FIG. 7B are understood to include or be included in block 396 of method 360 . In particular, as discussed above, the adjustment of the relative electrode positions in block 396 may create an error (ε) and redistribute the error. In particular, as noted above, the error can be incorporated into the location or selected location of the electrode 323 placement. Therefore, the errors may not be properly distributed between the electrodes on the initial or first pass. In other words, when determining the positions of electrodes based on calculated radii relative to other pairs of electrodes, errors in the calculations (eg, due to measurements) may correlate to one electrode more than the other. The redistribution error allows better identification of the distance between pairs of electrodes and allows better determination of the shape of the implantable device 226 .

Initially, when the relative positions of the electrodes are adjusted in block 396, a calculation of the expected pairwise capacitance may be performed in block 400. Calculations of expected pairwise capacitances can be based on well-known calculations such as direct calculations, conformal transformations, helper functions, and numerical approximations. The calculated pairwise capacitances may be based on the placement of the electrodes initialized in block 376 . Thus, calculations can be made based on the placement of electrodes 232, including the distance between them. Calculation of expected pairwise capacitances may be performed by a processor system, such as processor system 44 discussed above. The algorithm can calculate the expected pairwise capacitance based on the calculation formula discussed above.

具体地，所述函数可以是每个选定电极232对之间测得的电容与预期的电容之间的差的总和。同样，应当理解，电极对可以是任何选定数量的电极对的每一个电极与其它电极中的每个电极组成的对。此外，如上文所讨论的，测得的电容和/或期望的电容基于电极之间的距离。给定一对之间的距离，以与第一电极的距离为半径的圆应该与以与第二电极的距离为半径的圆相交，如图7A1和7A2所示出的，其中相对于所述对中的另一个电极，所述电极实际位于空间中。因此，在测得的电容与预期的电容之间的差(以上文所讨论的计算的)可能是由于测量误差或计算误差引起的。因此，误差ε可以分布在电极的选定位置或初始化位置之间，以提供更好的拟合，并且因此使函数F_o最小化。After calculating the expected pairwise capacitances in block 400 , based on the initialization tree from block 376 , a difference between the expected capacitances and the measured capacitances may be generated in block 402 by receiving the measured pairwise capacitances. Then, in block 404, a function (F _o ) is calculated using the measured capacitance sum and the difference (Δ _ij ) from the expected capacitance. The function (F _o ) can be any suitable function, such as a least squares function, such as

Specifically, the function may be the sum of the difference between the measured capacitance and the expected capacitance between each selected pair of electrodes 232 . Also, it should be understood that the electrode pairs may be any selected number of electrode pairs, each electrode of each electrode being paired with each electrode of the other electrodes. Furthermore, as discussed above, the measured capacitance and/or the expected capacitance is based on the distance between the electrodes. Given the distance between a pair, a circle with a radius of the distance from the first electrode should intersect a circle with a radius of the distance from the second electrode, as shown in Figures 7A1 and 7A2, where relative to the The other electrode in the pair, which is actually in the space. Therefore, the difference between the measured capacitance and the expected capacitance (calculated as discussed above) may be due to measurement error or calculation error. Therefore, the error ε can be distributed between the selected or initialized positions of the electrodes to provide a better fit and thus minimize the function F _o .

Once the function is calculated or determined in block 404 , the function may be optimized in block 406 at the electrode positions. As discussed above, the error may be included in the calculation or positioning of each of electrodes 232 in space, as discussed and shown in block 376 . Thus, assigning or applying more error to one electrode or the other may optimize the fit or reduce the error between the expected and measured positions of each electrode 232 . Thus, in block 406, the error may be adjusted or shifted between the different electrodes 232 calculated or determined in pairs.

The optimization of the function (including the error distribution that minimizes the function (F _o ) below) can be done in a selected manner, such as selectively or randomly applying errors to different ones of the electrodes. In various embodiments, the error redistribution and/or the determined shape may be adjusted by the following well-known methods: random motion algorithms (eg, Monte Carlo methods), local optimization methods (eg, gradient descent), global optimization methods (eg, parallel tempering) and pattern recognition methods (eg, deep neural networks). However, it should be understood that other suitable optimization algorithms may be used.

Thus, once the function F _o has been optimized in block 406 , a determination of the optimized or determined relative electrode positions may be made in block 410 . Then, in block 414, the determined relative electrode positions may be output. The output may be any suitable output, such as a signal to the navigation system 22, 24, a signal presenting a display, and the like.

The relative electrode positions in block 316 , including the adjusted relative electrode positions, may be used to determine the relative shape of the implantable device 226 . As discussed above, the relative positions of electrodes 232 that are fixed or positioned along the length of implantable device 226 may be used to determine the relative shape of implantable device 226 . The electrodes adjusted relative to position in block 396 may be used in block 420 to determine or output the relative shape of the implantable device. The shape of the implantable device 226 determined based on the electrode relative positions initialized in block 376 and/or the adjusted electrode relative positions selected in block 396 is the relative shape of the implant device 226 . Generally, as discussed above, implantable device 226 may be positioned or initially positioned relative to subject 36 . Accordingly, the shape of the implantable device 226 determined in block 420 may be used to determine the shape of the implantable device 226 within the patient 36 .

The determined relative shape of implantable device 226 relative to patient 36 may then be combined with the position information of implantable device 226 to determine the position of implantable device 226 relative to patient 36 . The combination of the shape determined in block 420 and the determined location may be combined in block 424 . The location determined by implantable device 226 may be based on various tracking devices, such as tracking device 70 (eg, tracking device 250). As discussed above, the tracking device 70 associated with the implantable device 226 may be registered to the patient 36 and/or the image 84 .

For example, a tracking device 250 associated with the implantable device 226 may be used to determine the location of at least one point or portion of the implantable device 226 . Thus, the position of at least one point on implantable device 226 relative to patient 36 is known. The shape determined in block 420 may be known relative to the tracking device 250 . Thus, in block 424, the shape of the tracked location of the implantable device 226 relative to the tracking device 250 is known or combined. Likewise, the shape determined in block 420 and the combination of the shape and the determined position in block 424 may be formed by execution of instructions by processor system 44a using the tracking information from tracking device 250 and the shape determined in block 420 .

Once combined in block 424 , the determined position and shape combined in block 424 may be output in block 428 . The shape and location of the output may be displayed as an icon (eg, 26i) on the display device 40 containing the image 84 . It should be understood that the icons may be displayed on other display devices, but may generally be shown as icons relative to the image data of subject 36 . For example, as discussed above, the positions tracked by the tracking device 250 may be registered to the patient 36 . A patient (defining patient space or subject space) may be registered to image 84 (defining image space). Accordingly, since the location tracked by tracking device 250 is known relative to image 40, and the shape is determined relative to tracking device 250, the determined shape of implantable device 226 may be displayed on image 40 as an icon. 34 The determined shape and position of the implantable device 226 can be viewed on the image 40 to assist in properly positioning the implantable device 226 at the selected or final location and to determine whether the implantable device is properly positioned. Target at selected locations or end users.

As discussed above, it should be appreciated that method 360 (including the various sub-algorithms or portions discussed above) may be provided as algorithms and instructions for execution by processing system 44 (including processor 44a). As discussed above, the algorithms may be executed by processor 44a based on instructions stored on memory 44b. Accordingly, the processor system 44 may allow the shape of the implantable device 226 within the patient 36 to be determined in a fast and efficient manner, while not being directly visible to the user 34 and/or being imaged by the imaging system. Thus, method 360 allows processor system 44 to efficiently and quickly determine the shape of implantable device 226 and the location of the shape of implantable device 226 for use during a selected procedure or operation.

The shape of implantable device 226 may also be determined and/or estimated in other ways. For example, estimating the shape of implantable device 226 may be accomplished using a single EM tracker, such as EM tracker 250 located at the tip of implantable device 226 . The positions previously tracked by the EM tracking device 250 may be used to determine or estimate the shape of the implantable device 226 . A trace of the previous position and/or the current position of the EM tracking device 250 may be displayed with or without the current determined position of the EM tracking device 250 using the display device. In addition to or alternatively to a single tracking device, multiple tracking devices may have positions determined simultaneously and/or over a period of time in the past. Past "tracked" locations can be determined as shapes, or a best fit can be made to past determined locations. Also, if the determined shape is selected, it can be displayed. For example, the shapes may be displayed as icons superimposed on image 84 .

With continued reference to FIGS. 1-6 and additional reference to FIG. 8 , the implantable device 226 may include a plurality of electrodes 232 . Each of the electrodes can be formed as a small coil that can operate in or emit a selected field to help track each of the electrodes 232, as discussed above. Electrode positioning. As known to those skilled in the art, the coils can sense electromagnetic fields and generate signals based on the sensed fields. Alternatively, the coil may emit a field that is sensed by the receiver. Regardless of the circumstances, the location of each of electrodes 232 can be determined.

In various embodiments, one or more of the electrodes 232 may be connected together even if the electrodes 232 are a solid or unitary member. It should be understood that each of the electrodes is connected to a communication line 233 . As discussed above, the communication line 233 may allow communication with the R&S 234 and/or other systems (eg, EP or EM tracking systems 22, 24). As discussed above, signals from electrodes 232 may be transmitted to respective tracking systems 22, 24 for selected position determinations.

Additionally, connections 450 may be formed between one or more of electrodes 232 . For example and only to facilitate the following discussion, the first connection 450a may be between the second electrode 232ii and the third electrode 232iii to form the first electrode coil 460 . Additionally, a connection 450b may be formed between the fourth electrode 232iv and the fifth electrode 232v to form the second electrode coil 462 . A third or alternative connection may interconnect more than two of electrodes 232 (eg, connection 452 interconnecting sixth electrode 232vi and ninth electrode 232ix) to form third electrode coil 466 . The connection 452 may thus not be connected or in contact with the electrodes between the sixth electrode 232vi and the ninth electrode 232ix. Additionally, connections such as connections 450 and 452 may electrically connect selected electrodes. In this manner, the first electrode coil 460 may be smaller than the third electrode coil 466 . Larger electrode coils 466 may produce a stronger signal or higher signal-to-noise ratio than smaller electrode coils 460 .

The electrode-to-electrode connections 450, 452 may be formed in any suitable manner. For example, a permanent or frangible connection may be formed between each of the electrodes, such as by wire or other conductive means. Furthermore, according to various embodiments, connections 450, 452 may be formed on cannula 290, such as using traces or other suitable mechanisms, to temporarily connect selected ones of electrodes 232, but once the cannula 290 is removed from the implantable device 226 removed, the connection can be removed. As discussed above, cannula 290 may be positioned over implantable device 226 to position implantable device 226 within patient 36 . The sleeve 290 may contain traces that form connections 450 , 452 between selected ones of the electrodes 232 . Connections 450, 452 may be substantially passive and not used to generate or transmit signals or power or to develop electrical potential with respect to other parts. As discussed further herein, connections 450 , 452 may simply be used to connect to selected ones of electrodes 232 . The connection of electrodes 232 to communication lines 233 may be used to transmit or receive signals relative to selected electrodes 232 .

With continued reference to FIG. 8 , the implantable device 226a may be substantially similar to the implantable device 226 shown in FIG. 3 . However, implantable device 226a may not include EM tracking device 250. However, various portions of the implantable device 226 may operate in combination with the EM tracking system 24 to provide a determination of the position and/or orientation of the implantable device 226a. As discussed herein, according to various embodiments, implantable device 226a (including communication line 233 ) may communicate with EM tracking system 24 to transmit signals to processor system 44 to assist in determining at least a portion of implantable device 226 positioning.

According to various embodiments, connections 450a and 450b may be connected to respective electrodes, such as adjacent electrodes. It should be understood, however, that connections 450a and 450b may not be connected to adjacent electrodes, or may not be connected to just two electrodes. As discussed above, connection 452 may connect more than one electrode. However, signals from one or more electrode coils may be transmitted. Although connected electrodes may be referred to herein as coils, it should be understood that coils may be formed due to corresponding connections, such as connection 450a between electrodes 232ii and 232iii, and that a single signal from the coil portion may be transmitted over communication line 233 to EM tracking system 24 . The connection 450a forms a coil 460 in combination with the two electrodes 232ii, 232iii. Similarly, coil 462 is formed by connection 450b, and a single coil 466 may be formed by connection 452 between electrodes 232vi to 232ix. It should be appreciated that coil 466 may be an effectively larger coil relative to coils 460, 462. It should be further understood that other coils may be formed by connections between other electrodes in the implantable device 226 and that the coils shown are for the present discussion only.

Coils 460 and 462 may operate with EM navigation system 24 as two separate coils. As discussed above, the signals from the coils 460 , 462 may be transmitted over the communication line 233 to the EM navigation system 24 . As discussed above, the coils may operate in the EM navigation system 24 in a manner similar to the operation of other known coils in EM navigation systems. Accordingly, those skilled in the art will understand that the coils 460, 462 may be used to sense fields (eg, with currents induced in the coils due to externally generated fields) and/or transmit the fields to be sensed by the receiver. Signals transmitted over communication line 233 may be used by EM navigation system 24 to transmit to processor system 44 and/or any suitable processor system to determine the location of coils 460, 462. The individual positioning of either of the coils 460, 462 may be determined based on the received signals.

In alternative and/or complementary operations, differential signals between the two coils 460, 462 may be used to determine the position and orientation of the two coils 460, 462. In other words, a signal may be transmitted regarding the difference in the sensed field between two near adjacent coils or adjacent coils. Such differential signaling can reduce or eliminate the effects of noise or interference on the transmitted signal.

Thus, it should be appreciated that the coils 460, 462 may operate in more than one operational manner to assist in determining the position of one or more of the coils 460, 462. However, the position of the implantable device 226 may be determined based on the signals from the coils 460 , 462 individually and/or as a differential signal between the two coils 460 , 462 . Thus, the electrodes 232 can operate as at least one pair to form a coil that can be used with the EM navigation system 24 to help determine the location of the coils 460, 462. It should be further understood that all electrodes 232 may be combined into selected pairs to form a coil along the length of the implantable device 226 .

Additionally, the coil 466 may be formed based on the connection 452 of more than two of the electrodes 232 . It should be further understood that any selected number of electrodes 232 may be connected to form a coil of selected size. Thus, any suitable or selected number (eg, ten or twelve of electrodes 232) may be combined to form a coil. However, regardless of the number of electrodes connected, the connected or larger coil 466 may also transmit signals over the communication line 233 to the EM navigation system 24 . The signals to the EM navigation system may be used to determine the location of the coil 466 to the determined location of the implantable device 226 . Likewise, the coil 466 may operate in a manner substantially similar to that of the coil in an EM navigation system as discussed above.

Accordingly, those skilled in the art will understand that one or more coils used by the EM navigation system 24 may be formed in the implantable device 226 to be based on the determined values of one or more of the coils 460 , 462 , 466 . Position and orientation to determine the position (eg, position and orientation) of implantable device 226 .

In addition to the location information determined by the EM navigation system 24 due to the coils 460, 462, 466, the shape of the implantable device 226 may also be determined as discussed above. Thus, as discussed above, the position of implantable device 226 may be used to determine positioning relative to subject 36 in a manner similar to the use of tracking device 250 . However, tracking device 250 may be removed from implantable device 226a, and one or more of electrodes 232 may be combined to form a selected coil (eg, coil 460), and the shape of implantable device 226a may be Determined in a manner similar to that discussed above. Accordingly, tracking devices such as tracking device 250 may not be incorporated as a separate element relative to implantable device 226a to determine the location of implantable device 226a.

Additionally, with reference to FIGS. 3 and/or 8 , each of the electrodes 232 may be in communication with the EM tracking system 24 . An EM tracking system including an array of localizers can generate a field that is sensed across two electrodes or a field that generates a potential difference across two electrodes (eg, first electrode 232i and second electrode 232ii). Although the two electrodes 232i, 232ii are not connected to conductive members associated with or formed by the implantable device 226, the electrodes may be in electrical communication due to the environment in which they are placed. For example, electrodes 232 are or may be positioned within subject 36 . Subject 36 may contain an amount of electrical conductivity, where the potential difference may be determined and communicated to EM tracking system 24 . The induced voltage may be based on the field emitted by the localizer EM navigation system 24 and may be used by the EM navigation system 24 to determine the position of the tracking device or the potential difference between the two electrodes 232i and 232ii. Likewise, those skilled in the art will understand that, as discussed above, the electrical connection between electrodes 232i and 232ii may form or allow a potential difference to be determined to allow tracking or determination of the electrodes' position.

Thus, it should be understood that tracking device 250 may not need to be incorporated into implantable device 226 (eg, implantable device 226a). However, the included electrodes 232 may be used with the EM tracking system 24 to determine the position (eg, location and orientation) of at least a portion of the implantable device 226 . As also discussed herein, this location may be used alone and/or in combination with the determined shape of the implantable device 226 . Furthermore, once the position and/or shape is determined, the position of implantable device 226 may be shown as an icon superimposed on image 84 of subject 36 . Thus, the user 34 is able to view the determined position and shape of the implantable device 226 during the procedure.

Accordingly, implantable device 226 may be positioned within cochlea 37 for tracking using a selected tracking system, such as EP tracking system 22 or EM tracking system 24. As discussed above, the selected EM tracking device 70b may be associated with the implantable device 226 , ie, either incorporated into the implantable device 226 or disposed on the removable member 290 relative to the implantable device 226 . middle. The EM tracking device 70b may be tracked using the EM tracking system 24 to help determine the position and shape of the implantable device 226, such as within the cochlea 37. In such systems, during implantation of implantable device 226, transmission line 233 may be reused or reassigned from the initial transmit tracking device signal to transmit when connected to the receiver and stimulator as part of a cochlear stimulation system analog signal.

In addition to or alternatively to the EM tracking device 70b, the electrodes 232 of the implantable device 226 may be used in the EP tracking system 24 to identify various features of the implantable device 226. For example, as discussed above, the shape of the implantable device 226 may be determined based on the relative capacitance between the various electrodes 232 of the implantable device 226 . Thus, when the implantable device 226 is positioned in the cochlea 37, the shape of the implantable device 226 can be determined. Additionally, electrodes 232 of implantable device 226 may be used with shaft electrodes (eg, shaft electrodes 60a-60c) to determine the location of implantable device 226 within patient 36. The determined position of implantable device 226 using EP tracking system 24 may be registered to image 84, or may be shown or determined relative to shaft electrodes 60a-60c. Those skilled in the art will understand that the EP tracking system 22 need not be registered to the image 84 , but rather it may be tracked relative to the shaft electrodes 60a - 60c positioned on the patient 36 . In any event, the shape and/or position of implantable device 226 may be determined by measuring the voltage and/or capacitance at individual electrodes 232 along the length of implantable device 226 .

Furthermore, the translation or distance between the respective EM tracking device and EP tracking device can be determined using the selected external image modality or additional image modalities. For example, if both tracking devices are radiopaque, fluoroscopy can be used to determine the distance between the two tracking devices. Fluoroscopy may be used, at a minimum, to determine certain information, although methods such as those available for fluoroscopy may be selected during surgery to eliminate or substantially reduce the use of ionizing radiation.

Additional imaging systems may also be used to obtain patient 36 information or information about mapping or trackable devices. Imaging systems may include ultrasound (US), computed tomography (CT), magnetic resonance imaging (MRI), and other suitable imaging techniques may be used. For example, the US system may be used to image or view the location of the selected tracking device within the patient 36 . A US transducer can be used to view the tracked device and determine its location within the patient 36 . Accordingly, the positioning of the instrument within the patient 36 can be imaged using the selected imaging system. As discussed above, this may also be used to determine the distance between two tracked devices within the patient 36, such as for translation or registration purposes between the two tracking systems 22, 24.

传输协议和硬件的传输、使用无线网络(例如，局域网)硬件和/或协议或方案(如IEEE 802.11无线LAN系统)的传输或使用其它合适的通信系统和协议的传输。The R&S 234 may also include various wired or wireless communication systems for communicating with one or both of the tracking systems 22, 24. Implantable device 226 , which may be placed in the cochlea of subject 36 , may be connected to R&S 234 during implantation of implant 226 . As discussed above, signals from any of the selected tracking devices 70a (eg, electrodes 232 ), 70b (eg, tracking device 250 ) may be communicated to the R&S 234 . The signals may relate to various sensed fields, capacitances, etc., as discussed above. The signals may be wirelessly transmitted to the respective tracking systems 22,24. Therefore, a direct connection of the tracking devices 70a, 70b from the cochlear implant 226 to the corresponding tracking system 22, 24 may not be necessary, as communication with the R&S 234 may be performed first and then with the corresponding tracking system 22, 24 communication. The wireless transmission can be any suitable transmission, such as using known

Transmission protocols and hardware, using wireless network (eg, local area network) hardware and/or protocols or schemes (eg, IEEE 802.11 wireless LAN systems) or using other suitable communication systems and protocols.

As indicated above, image data of the subject can be acquired. The image data may be used to generate image 84 for display on display device 40 or any suitable display device. In various embodiments, once implantable device 226 is positioned within patient 36, user 34 may view image 84 and determine the selected or predetermined shape of the implantable device. The user 34 may enter or store the predetermined shape in the memory 44b by entering the selected shape or the predetermined shape using an input device (eg, the keyboard 48). It should be understood that the selection or predetermination of the shape of the implantable device 226 may be performed at any suitable time and need not be performed in an operating room, as shown in FIG. 1 .

However, the predetermined shape may be transferred to memory 44b for access using processor 44a. Accordingly, the predetermined shape of the implant 226 may be shown relative to the image 84 as shown by an icon superimposed on the image 84 . During surgery, such as during positioning of implantable device 226 within patient 36 , the determined shape and/or position of implantable device 226 as discussed herein may be shown on display 40 . User 34 may then compare the determined or tracked position and/or shape of implantable device 226 relative to the predetermined position and/or shape. In addition, workstation 44 may execute instructions stored on memory device 44b to compare the determined shape and/or position to a predetermined shape and/or position (eg, a fit comparison). The matching percentage or matching coefficient of the current shape of the implantable device 226 and the tracked shape relative to the predetermined shape may be displayed.

Additionally, user 34 may determine (eg, in real time) whether the shape is the selected shape based on the determined position and/or shape of implantable device 226 displayed on display device 40 . Thus, user 34 may view display 40 or other suitable selected display during surgery relative to image 84 . User 34 can then see if the shape of image 84 is the selected shape.

Accordingly, methods of tracking and determining the shape of the positioning of the implantable device 226 as discussed above can be used to efficiently perform procedures to reduce the number of procedures and/or to confirm or select a suitable or optimal positioning of the implantable device 226 .

The foregoing description of the embodiments has been provided for the purposes of illustration and description. The above description is not intended to be exhaustive or to limit the invention. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. Individual elements or features of particular embodiments may also be varied in numerous ways. Such changes are not to be considered a departure from the present invention, and all such modifications are intended to be included within the scope of the present invention.

Claims (80)

1. A system for tracking an implantable cochlear stimulator electrode assembly, comprising: a localizer positioned near the subject in which the implantable cochlear stimulator electrode assembly is to be positioned; a processor system configured to receive signals from a trackable portion associated with the implantable cochlear stimulator electrode assembly; and a display device configured to display the position of the implantable cochlear stimulator electrode assembly; wherein the implantable cochlear stimulator electrode assembly includes at least one electrode portion configured to emit to stimulate the cochlea of the subject. 2. The system of claim 1, wherein the locator comprises: a driver configured to generate current; and at least one shaft electrode configured to be positioned in contact with the subject; wherein the at least one shaft electrode is configured to generate an electrical potential relative to at least one electrode of the implantable cochlear stimulator electrode assembly. 3. The system of claim 2, wherein the at least one shaft electrode comprises a first shaft electrode, a second shaft electrode, and a third shaft electrode; wherein the at least one electrode of the implantable cochlear stimulator electrode assembly is configured to sense a first electrical potential relative to the first axial electrode, a second electrical potential relative to the second axial electrode, and a relative a third potential at the third axis electrode; wherein the processor system is configured to determine the position of the at least one electrode relative to each of the first shaft electrode, the second shaft electrode, and the third shaft electrode. 4. The system of any one of claims 1 to 3, wherein the at least one electrode portion of the implantable cochlear stimulator electrode assembly comprises a plurality of implant electrode portions. 5. The system of any one of claims 1 to 4, wherein the at least one electrode portion of the implantable cochlear stimulator electrode assembly is configured to sense voltage during implantation, and is configured to to emit the stimulus to the cochlea after implantation. 6. The system of any one of claims 1, 4, and 5, wherein the positioner comprises a coil configured to generate an electromagnetic field. 7. The system of claim 6, further comprising: a removable sleeve positionable over the implantable cochlear stimulator electrode assembly; wherein the trackable portion includes an EM tracking device configured to have a signal induced in the EM tracking device based on the generated electromagnetic field; wherein the EM tracking device is secured to the movable sleeve; wherein the location of the EM tracking device is determined by the processor system executing instructions based on the signal; wherein the removable sleeve remains at a selected fixed position relative to the implantable cochlear stimulator electrode assembly during implantation. 8. The system of claim 7, wherein the removable sleeve comprises a frangible portion; wherein the frangible portion is ruptured after the implantable cochlear stimulator is in the selected implantation location to remove the removable sleeve from the implantable cochlear stimulator electrode assembly. 9. The system of claim 6, wherein the trackable portion is an EM tracking device configured to have signals induced in the EM tracking device based on the generated electromagnetic field; wherein the EM tracking device is secured to a portion of the implantable cochlear stimulator electrode assembly. 10. The system of claim 6, wherein the at least one electrode portion of the implantable cochlear stimulator electrode assembly is formed as a coil of conductive material; The at least one electrode portion therein formed as a coil and configured to have induced in the coil a current due to the electromagnetic field is in the trackable portion. 11. The system of any one of claims 1, 4, and 5, wherein the positioner comprises at least three shaft electrodes; wherein each of the at least three shaft electrodes is driven to inject current between each of the at least three shaft electrodes and a corresponding pair of shaft electrodes of the at least three shaft electrode pairs into the subject; wherein the at least one electrode portion is the trackable portion; wherein the at least one electrode is configured to sense capacitance due to the injected current with respect to each shaft electrode pair. 12. The system of claim 12, wherein each of the at least three shaft electrodes injects current at a unique frequency or at a unique time. 13. A system for tracking an implantable cochlear stimulator electrode assembly, comprising: a localizer configured to be positioned near a subject within which the implantable cochlear stimulator electrode assembly is to be positioned; wherein the localizer is capable of at least one of generating a field or injecting an electrical current into the subject, and wherein the electrode portion is formed with the implantable cochlear stimulator electrode assembly, the implantable cochlear stimulator electrode assembly configured to perform at least one of: sensing the field or sensing the current based on the current measuring voltage; a processor system configured to receive signals from the electrode portion originally used as a tracking device associated with the implantable cochlear stimulator electrode assembly; and a display device configured to display at least one of a position or shape of the cochlear stimulator electrode assembly; wherein the electrode portion of the implantable cochlear stimulator electrode assembly is configured to transmit stimulation signals to the cochlea of the subject. 14. The system of claim 13, wherein the positioner comprises at least one coil of conductive material for generating the field; wherein the field is an electromagnetic field. 15. The system of claim 13, wherein the positioner comprises at least one shaft electrode configured to inject the electrical current into the subject. 16. The system of claim 15, wherein the at least one shaft electrode comprises at least three shaft electrodes; wherein each of the at least three shaft electrodes is driven to inject electrical current into the subject; wherein each of the at least three shaft electrodes injects current at a unique frequency. 17. The system of claim 16, wherein the processor system is configured to triangulate at least the Euclidean coordinate positioning of the electrodes relative to the at least three axis electrodes. 18. A method for tracking a cochlear stimulator electrode assembly, comprising: positioning a localizer near a subject within which the implantable cochlear stimulator electrode assembly is to be positioned; operating the positioner to at least one of: generate a field or inject a current; A tracking system having a processor system is operated to receive signals from a tracking device having the cochlear stimulator electrode assembly, the cochlear stimulator electrode assembly being configured to at least one of sense the field or sensing a voltage based on the current; displaying the location of the cochlear stimulator electrode assembly on a display device; and The electrode portion of the cochlear stimulator electrode assembly is configured to transmit stimulation signals to the cochlea of the subject. 19. The method of claim 18, further comprising: coupling the cochlear stimulator electrode assembly to the tracking system to receive the signal from the tracking device; configuring the electrode portion as the tracking device, wherein the electrode portion is an electrode formed with the cochlear stimulator electrode assembly, wherein the electrode portion is initially used in relation to the cochlear stimulator electrode assembly linked said tracking device; and After operating the electrode portion as the tracking device, the electrode portion of the cochlear stimulator electrode assembly is configured to transmit the stimulation signal to the cochlea of the subject. 20. The method of claim 19, further comprising: decoupling the cochlear stimulator from the tracking system; and coupling the cochlear stimulator to a stimulator; wherein the stimulator is configured to provide a signal to the electrode portion to stimulate the cochlea of the subject. 21. The method of claim 19, further comprising: positioning at least a first axial electrode, a second axial electrode, and a third axial electrode relative to the subject; operating a driver configured to generate a first current to be injected by the positioned first shaft electrode at a first frequency or at a first time; operating the driver configured to generate a second current to be injected by the positioned second shaft electrode at a second frequency or at a second time; operating the driver configured to generate a third current to be injected by the positioned third shaft electrode at a third frequency or at a third time; operating the processor system to determine, by the processor system executing instructions, relative to each of the first axial electrode, the second axial electrode and the third axial electrode the at least one electrode location; and The determined position is displayed using the display. 22. The method of claim 18, further comprising: The tracking device is removed from the cochlear stimulator. 23. The method of claim 22, wherein removing the tracking device comprises withdrawing a guidewire with the tracking device from a cannula positioned with the cochlear stimulator. 24. The method of claim 22, wherein removing the tracking device comprises: rupturing a frangible portion of a cannula positioned over the cochlear stimulator; and Move the cannula from the cochlear stimulator. 25. A system for tracking an implantable cochlear stimulator electrode assembly, comprising: A positioner having at least three pairs of shaft electrodes, wherein each pair of shaft electrodes is attached to a subject and is driven to inject current into the subject between each pair of shaft electrodes of the at least three pairs of shaft electrodes in the subject's body; an electrode portion of an implantable stimulator electrode array configured to sense a voltage based at least on the injected current; a processor system configured to receive signals from the electrode portion originally used as a tracking device associated with the implantable cochlear stimulator electrode assembly; and a display device configured to display at least one of a position or shape of the cochlear stimulator electrode assembly; wherein the electrode portion of the implantable cochlear stimulator electrode assembly is configured to transmit stimulation signals to the cochlea of the subject. 26. The system of claim 25, wherein the electrode portion is configured to connect to a stimulator to transmit the stimulation signal to the cochlea after implantation of the implantable cochlear stimulator electrode assembly. 27. The system of any one of claims 25 or 26, wherein the processor system is configured to triangulate at least the Euclidean coordinate positioning of the electrodes relative to the at least three axial electrode pairs Measurement. 28. A system for tracking an implantable cochlear stimulator electrode assembly, comprising: a localizer positioned near the subject in which the implantable cochlear stimulator electrode assembly is to be positioned; and a processor system configured to receive signals from a trackable portion within the implantable cochlear stimulator electrode assembly; wherein the implantable cochlear stimulator electrode assembly includes a first electrode portion initially configured as the trackable portion and subsequently configured as the implantable cochlear stimulator electrode The assembly then transmits stimulation to the subject's cochlea. 29. The system of claim 28, further comprising: A display device configured to display the position of the implantable cochlear stimulator electrode assembly. 30. The system of any one of claims 28 or 29, wherein the first electrode portion comprises: A coil of conductive material having a plurality of coils of said conductive material wound around a core. 31. The system of claim 30, wherein the core is an air core; wherein the core extends along an axis extending from a central longitudinal axis of the implantable cochlear stimulator electrode assembly. 32. The system of any one of claims 30 or 31, wherein the first electrode in a subsequent configuration transmits a stimulation signal using at least a portion of the coil in contact with the subject. 33. The system of any one of claims 28 to 32, wherein the implantable cochlear stimulator electrode assembly extends a length along a longitudinal axis and is configured to be implanted in the cochlea of the subject middle. 34. The system of any one of claims 28 to 33, further comprising: a sheath configured to cover at least a portion of the length of the implantable cochlear stimulator electrode assembly; and a sheath connector formed on the inner surface of the sheath; wherein the implantable cochlear stimulator electrode assembly includes a second electrode portion; wherein the sheath connector is configured to electrically connect at least the first electrode portion and the second electrode portion. 35. The system of claim 34, further comprising: a first electrode part connector; the second electrode part connector; wherein the sheath connector forms a coil when electrically connecting at least the first electrode portion and the second electrode portion; Wherein the locator can be used to generate an electromagnetic field that induces a current in the coil. 36. The system of claim 35, wherein the first electrode portion and the second electrode portion are integral electrode portions. 37. The system of claim 35, wherein the first electrode and the second electrode are spaced apart. 38. The system of claim 37, wherein the implantable cochlear stimulator electrode assembly comprises a third electrode portion; wherein the third electrode portion is located between the first electrode portion and the second electrode portion; wherein the sheath connector is not electrically connected to the third electrode portion. 39. The system of claim 38, wherein the sheath includes a frangible portion configured to allow removal of the sheath after implantation of the implantable cochlear stimulator electrode assembly. set. 40. The system of claim 28, further comprising: a sheath configured to cover at least a portion of the length of the implantable cochlear stimulator electrode assembly; and a first sheath connector and a second sheath connector formed on the inner surface of the sheath; wherein the implantable cochlear stimulator electrode assembly includes a plurality of electrode portions of the first electrode portion; wherein the first sheath connector is configured to electrically connect at least a first sub-plurality of electrode portions of the plurality of electrode portions, and the second sheath connector is configured to electrically connect the plurality of electrodes at least a second sub-plurality of electrode portions in the portion; wherein the first sub-plurality of electrode portions of the plurality of electrode portions form a first coil configured to have a first current induced therein, and all of the plurality of electrode portions The second sub-plurality of electrode portions form a second coil configured to have a second current induced therein. 41. The system of claim 40, wherein the plurality of electrode portions are all single unitary electrode portions. 42. A system for tracking an implantable cochlear stimulator electrode assembly, comprising: a localizer positioned near the subject in which the implantable cochlear stimulator electrode assembly is to be positioned; a processor system configured to receive signals from a trackable portion within the implantable cochlear stimulator electrode assembly; and a sheath configured to cover at least a portion of the length of the implantable cochlear stimulator electrode assembly; and a first sheath connector formed on the inner surface of the sheath; wherein the implantable cochlear stimulator electrode assembly includes a plurality of electrode portions that are initially configured as the trackable portion and subsequently configured to be implanted in the implantable cochlear stimulator electrode The assembly then transmits a stimulus to the cochlea of the subject; wherein the first sheath connector is configured to electrically connect at least a first sub-plurality of electrode portions of the plurality of electrode portions to form a first coil, the first coil being configured to have a position formed by the positioner The resulting field induces a first current in the first coil. 43. The system of claim 42, further comprising: A display device configured to display the determined position of the cochlear stimulator electrode assembly based on the induced current. 44. The system of any one of claims 42 or 43, further comprising: a second sheath connector formed on the inner surface of the sheath; wherein the second sheath connector is configured to electrically connect at least a second sub-plurality of electrode segments of the plurality of electrode segments; wherein the second sub-plurality of electrode portions of the plurality of electrode portions form a second coil configured to have a second current induced therein. 45. The system of claim 43, wherein the first coil can be used to track separately from the second coil. 46. The system of claim 42, further comprising: A tracking device separate from the implantable cochlear stimulator electrode assembly and configured to mount to the implantable cochlear stimulator electrode assembly. 47. A method for tracking a cochlear stimulator electrode assembly, comprising: positioning a localizer near a subject within which the implantable cochlear stimulator electrode assembly is to be positioned; operating the locator to generate a field; providing a cochlear stimulator electrode assembly having a plurality of electrode portions; positioning a sheath to cover at least a portion of the length of the cochlear stimulator electrode assembly; and electrically connecting at least a first sub-plurality of electrode portions of the plurality of electrode portions to form a first coil having a first sheath connector formed on an inner surface of the sheath; operating a tracking system having a processor system to receive signals from the first coil; and At least one electrode portion of the plurality of electrode portions of the cochlear stimulator electrode assembly is configured to transmit stimulation signals to the cochlea of the subject. 48. The method of claim 47, wherein configuring at least one electrode portion of the plurality of electrode portions of the cochlear stimulator electrode assembly to transmit stimulation signals to the cochlea of the subject comprises Remove the sheath from the cochlear stimulator electrode assembly. 49. The method of claim 48, wherein removing the sheath comprises rupturing the sheath at a frangible region. 50. The method of any one of claims 47 to 49, further comprising: The location of the cochlear stimulator electrode assembly is displayed on a display device. 51. The method of any one of claims 47 to 50, further comprising: The at least one of the first sheath connector or the cochlear stimulator electrode assembly is coupled to the tracking system to receive the signal from the first coil. 52. The method of claim 51, further comprising: decoupling at least one of the coupled at least one of the first sheath connector or the cochlear stimulator electrode assembly from the tracking system; and coupling the cochlear stimulator to a stimulator; wherein the stimulator is configured to provide a signal to the electrode portion to stimulate the cochlea of the subject. 53. A system for placing an implantable cochlear stimulator electrode assembly, comprising: the implantable cochlear stimulator electrode assembly includes a plurality of implant electrode portions and a conductive connector from each implant electrode portion of the plurality of implant electrode portions; a processor system configured to (i) receive signals from at least a first electrode portion and a second electrode portion of the plurality of implant electrode portions, and (ii) determine the first electrode portion and the the relative position of the second electrode portion within the subject; and a display device configured to display at least the shape of the implantable cochlear stimulator electrode assembly; wherein at least a sub-plurality of implant electrode segments of the plurality of implant electrode segments are configured to stimulate the cochlea of the subject. 54. The system of claim 53, further comprising: A localizer positioned near the subject in which the implantable cochlear stimulator electrode assembly is to be positioned. 55. The system of claim 54, wherein the locator comprises: a driver configured to generate current; and at least one shaft electrode configured to be positioned in contact with the subject; wherein the at least one shaft electrode is configured to generate an electrical potential relative to at least the first electrode portion and the second electrode portion of the plurality of implant electrode portions. 56. The system of claim 54, wherein the signal received from at least the first electrode portion and the second electrode portion of the plurality of implant electrode portions comprises a first electrode portion of the first electrode portion a first signal of a capacitance and a second signal of a second capacitance of the second electrode portion; wherein the processor system is configured to determine the relative positions of the first electrode portion and the second electrode portion within the subject by executing instructions to determine the relative positions of the first and second electrode portions based on the first signal and the second The difference between the signals determines the relative position of the first electrode portion and the second electrode portion. 57. The system of claim 56, wherein the processor system is further configured to determine the cochlear implantable stimulation based on the determined relative positions of the first electrode portion and the second electrode portion shape of at least a portion of the electrode assembly. 58. The system of claim 55, wherein the processor system is further configured to determine based on the measured capacitance between at least one pair of implant electrode portions of the plurality of implant electrode portions A shape of the implantable cochlear stimulator including the plurality of implant electrode portions. 59. The system of claim 58, wherein the display device is configured to display the determined shape. 60. The system of claim 56, wherein the at least one electrode portion of the implantable cochlear stimulator electrode assembly is operable in a first configuration to sense the voltage during implantation, and is operable in a first configuration The second configuration operates to emit a signal for stimulating the cochlea after implantation. 61. The system of claim 59, further comprising: a tracking device configured to sense the field emitted by the locator; wherein the tracking device is secured to the implantable cochlear stimulator; wherein the processor is further configured to determine the location of the tracking device; Wherein the display device can be used to display an icon showing the shape of the cochlear stimulator relative to the determined position of the tracking device. 62. The system of claim 53, wherein the conductive connector is selectively connectable to a stimulator to transmit stimulation signals from the stimulator to each of the plurality of implant electrode portions Implant electrode section. 63. The system of claim 54, wherein the locator comprises a direct multiple input capacitance meter multiplexing at least one of channel, time, frequency, or a combination thereof. 64. The system of claim 54, wherein the positioner comprises a coil configured to generate an electromagnetic field. 65. A system for tracking an implantable cochlear stimulator electrode assembly, wherein the implantable cochlear stimulator electrode assembly comprises a plurality of implant electrode portions and conductive connectors from Each implant electrode portion of the plurality of implant electrode portions extends, and the system includes: a localizer configured to be positioned near a subject in which the implantable cochlear stimulator electrode assembly is to be positioned; wherein the localizer is capable of at least one of generating a field or injecting an electrical current into the subject, wherein each implant electrode of the plurality of implant electrodes is formed to sense a voltage based on the current, wherein a signal based on the sensed voltage is transmitted on the conductive connector; A processor system configured to: receiving a signal from each of the plurality of implant electrodes, determining the capacitance between electrode pairs in the plurality of implant electrodes, executing instructions to determine a relative position between electrodes of the electrode pair of the plurality of implant electrodes; a display device configured to display at least one of a position of at least a portion of the cochlear stimulator electrode assembly or a determined relative position of the electrode pair; wherein the plurality of implant electrodes of the implantable cochlear stimulator electrode assembly are configured for stimulating the cochlea of the subject. 66. The system of claim 65, wherein the locator comprises a capacitance meter connected by the conductive connection extending from each implant electrode portion of the plurality of implant electrode portions a connector connected to the plurality of implant electrode portions; wherein the positioner is configured to measure the capacitance of at least a first electrode portion and a second electrode portion or a capacitance between the first electrode portion and the second electrode portion. 67. The system of claim 65, wherein the positioner comprises at least one shaft electrode configured to inject the electrical current into the subject. 68. The system of claim 67, wherein the at least one shaft electrode comprises at least three shaft electrodes; wherein each of the at least three shaft electrodes is driven to inject electrical current into the subject; wherein each of the at least three shaft electrodes injects a current. 69. The system of claim 65, wherein the processor system is further configured to perform insertion to: determining a capacitance between each electrode portion of the plurality of implant electrode portions spaced along the length of the implantable cochlear stimulator electrode assembly and all other electrode portions of the plurality of implant electrode portions; and The shape of the implantable cochlear stimulator electrode assembly is determined based on the capacitance between each implant electrode portion of the plurality of implant electrode portions. 70. The system of claim 69, further comprising: a memory system having the instructions stored thereon; where the instructions include: initializing possible positions for each of the plurality of implant electrode portions, Optimizing the determined position of each electrode section based on the initial possible position of each electrode section, and The determined shape of the implantable cochlear stimulator electrode assembly is output based on the optimized position of each electrode portion. 71. The system of claim 70, wherein the processor system is further configured to display the implantable cochlear stimulator electrode assembly on an image of the subject displayed on the display device of the determined shape. 72. The system of claim 70, wherein the memory system contains stored predetermined selected shapes of the implantable cochlear stimulator electrode assembly, and the processor is configured to store the implantable cochlear stimulator electrode assembly The determined shape of the output of the cochlear stimulator electrode assembly is compared to the stored predetermined selected shape of the implantable cochlear stimulator electrode assembly. 73. The system of claim 72, wherein the processor is further configured to output the determined shape (i) of the output of the implantable cochlear stimulator electrode assembly with the cochlear implantable the predetermined selected shape of the stimulator electrode assembly is similar, (ii) unlikely based on the image of the subject, or (iii) similar to the implantable cochlear stimulator electrode assembly of said predetermined selected shapes are dissimilar indications. 74. A method for tracking a cochlear stimulator electrode assembly, comprising: measuring the capacitance between the first electrode portion and the second electrode portion along the length of the cochlear stimulator electrode assembly; determining the relative position of the first electrode portion and the second electrode portion based on the measured capacitance; and The shape of the cochlear stimulator electrode assembly at least between the first electrode portion and the second electrode portion is displayed on a display device based on the determined relative position. 75. The method of claim 74, further comprising: A current is injected to measure the capacitance. 76. The method of claim 74, wherein measuring the capacitance between a first electrode portion and a second electrode portion along the length of the cochlear stimulator electrode assembly comprises connecting a meter directly to the first electrode portion and the second electrode portion, and at least one of measuring the capacitance at each of the first electrode portion and the second electrode portion, or measuring the first electrode portion and the second electrode difference in capacitance between sections. 77. The method of claim 74, further comprising: At least one of the first electrode portion and the second electrode portion is operated to transmit stimulation to the cochlea of the subject. 78. The method of claim 74, further comprising: determining a capacitance between each electrode portion of a plurality of electrode portions spaced along the length of the cochlear stimulator electrode assembly and all other electrode portions of the plurality of electrode portions, wherein the first electrode portion and the second electrode portion is two electrode portions of the plurality of electrode portions; determining a relative position between each electrode portion of the plurality of electrode portions and each other electrode portion of the plurality of electrode portions based on the determined capacitance; and The shape of the cochlear stimulator electrode assembly is determined based on the capacitance between each of the plurality of electrode portions. 79. The system of claim 78, further comprising: A processor system is operated to invoke instructions stored on the processor system from a memory system, wherein the instructions include: initializing possible positions of at least one electrode portion of the plurality of electrode portions, Optimizing the determined position of each electrode section based on the at least one electrode section based on an initial possible position, and The determined shape of the cochlear stimulator electrode assembly is output based on the determined optimized position of each electrode portion. 80. The method of claim 79, further comprising: The processor system is operated to display on a display device the determined shape of the cochlear stimulator electrode assembly to be superimposed on an image of the subject.

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