JP2025145702A - Diagnostic imaging catheters - Google Patents

Abstract

To provide an image diagnostic catheter equipped with a conductive ring part and a conductive brush part.SOLUTION: An image diagnostic catheter includes: an ultrasonic transmission/reception part; a housing for supporting the ultrasonic transmission/reception part; an electric signal line connected electrically with the ultrasonic transmission/reception part; a shaft body connected to a proximal side of the housing; and a hub member for covering a proximal end part of the shaft body and supporting the shaft body relatively rotatably. The proximal end part of the shaft body includes a conductive ring part electrically connected to the electric signal line, and the hub member includes a conductive brush part that comes in contract with the conductive ring part.SELECTED DRAWING: Figure 4

Description

This disclosure relates to a catheter for diagnostic imaging.

Diagnostic imaging catheters that use intravascular ultrasound (IVUS) to obtain images for diagnosing diseased areas within a living body have been known for some time. Patent Document 1 discloses this type of diagnostic imaging catheter. The diagnostic imaging catheter described in Patent Document 1 includes a drive shaft. Patent Document 1 also discloses an external device to which the diagnostic imaging catheter is connected. The external device described in Patent Document 1 includes a motor for rotating the drive shaft of the diagnostic imaging catheter.

JP 2017-51500 A

The external device described in Patent Document 1 typically includes a conductive ring portion and a conductive brush portion that constitute a slip ring brush. By including a conductive ring portion and a conductive brush portion in the external device, when the external device generates an intraluminal image based on ultrasound signals acquired from an imaging diagnostic catheter using IVUS, it is possible to maintain the electrical connection between the ultrasonic transmitter/receiver unit (which acts as a rotating body) and the external device (which acts as a stationary body) while suppressing physical twisting of the part connecting the two.

However, the conductive ring portion and conductive brush portion are subject to wear due to sliding. Wear caused by sliding of the conductive ring portion and conductive brush portion generates wear debris. This wear debris may cause image noise in intracavitary images based on ultrasound signals. Therefore, when a conductive ring portion and conductive brush portion are installed in an external device that serves as a repeatedly used drive unit, they must be durable enough to withstand long-term use, and highly durable conductive ring portions and conductive brush portions must be used. On the other hand, it is also possible to configure the external device so that the conductive ring portion and conductive brush portion are replaceable. In this case, the external device must be configured so that the conductive ring portion and conductive brush portion are replaceable. This can result in a complex configuration of the external device. Therefore, it is preferable to have a diagnostic imaging catheter that can be used with an external device, regardless of whether the external device has a conductive ring portion and conductive brush portion.

The present disclosure aims to provide a catheter for diagnostic imaging that includes a conductive ring portion and a conductive brush portion.

A diagnostic imaging catheter according to a first aspect of the present disclosure includes:
(1)
an ultrasonic transmitting and receiving unit;
a housing supporting the ultrasonic transmitter/receiver;
an electric signal line electrically connected to the ultrasonic transmitting/receiving unit;
a shaft body connected to a proximal side of the housing;
a hub member that covers a proximal end of the shaft body and supports the shaft body so that it can rotate relatively,
the proximal end of the shaft body includes a conductive ring portion electrically connected to the electrical signal line;
The hub member is a catheter for diagnostic imaging, and includes a conductive brush portion that contacts the conductive ring portion.

A catheter for diagnostic imaging according to one embodiment of the present disclosure includes:
(2)
The shaft body is
A coil shaft portion;
a conductive connection pipe portion that is covered by the hub member and attached to the coil shaft portion,
In the diagnostic imaging catheter according to (1) above, the conductive ring portion is the connecting pipe portion.

A catheter for diagnostic imaging according to one embodiment of the present disclosure includes:
(3)
The shaft body is
A coil shaft portion;
a connecting pipe portion that is covered by the hub member and attached to the coil shaft portion;
a ring body supported on the outer surface of the connecting pipe section and having a lower electrical resistance than a layer constituting the outer surface of the connecting pipe section,
In the diagnostic imaging catheter according to (1) above, the conductive ring portion is the ring body.

A catheter for diagnostic imaging according to one embodiment of the present disclosure includes:
(4)
The diagnostic imaging catheter according to (3) above, wherein the layer constituting the outer surface of the connecting pipe portion is made of an insulating material.

A catheter for diagnostic imaging according to one embodiment of the present disclosure includes:
(5)
The diagnostic imaging catheter is described in any one of (1) to (4) above, wherein the electrical signal line extends in the longitudinal direction of the shaft body through a hollow portion defined inside the shaft body.

A catheter for diagnostic imaging according to one embodiment of the present disclosure includes:
(6)
The hub member is
an insertion passage through which the shaft body is inserted;
an injection path that communicates with the insertion passage at a communication portion between the distal end and the proximal end of the insertion passage and that allows a liquid to be injected into the insertion passage from the outside;
the hub member includes a seal portion that closes the insertion passage around the shaft body at a position in the insertion passage that is closer to the proximal side than the communication portion,
The catheter for diagnostic imaging described in any one of (1) to (5) above, wherein the conductive ring portion of the shaft body and the conductive brush portion of the hub member are arranged proximal to the seal portion.

A catheter for diagnostic imaging according to one embodiment of the present disclosure includes:
(7)
the hub member includes a connector portion connectable to a drive device that can drive the shaft body so as to rotate the shaft body relative to the hub member,
The catheter for diagnostic imaging described in any one of (1) to (6) above, wherein the conductive ring portion of the shaft body and the conductive brush portion of the hub member are positioned distal to the connector portion.

A catheter for diagnostic imaging according to one embodiment of the present disclosure includes:
(8)
The diagnostic imaging catheter according to any one of (1) to (7) above, further comprising a sheath that houses the ultrasonic transmitter/receiver unit, the housing, the electrical signal line, and the shaft body, on the distal side of the hub member.

The present disclosure provides a catheter for diagnostic imaging that includes a conductive ring portion and a conductive brush portion.

1 is a diagram showing an imaging diagnostic system including a catheter for imaging diagnostics according to an embodiment of the present disclosure. 2 is a diagram showing the diagnostic imaging catheter shown in FIG. 1 alone, showing a state in which a probe and an inner tube are pushed in. FIG. 2 is a diagram showing the diagnostic imaging catheter shown in FIG. 1 alone, showing a state in which the probe and the inner tube are pulled out. FIG. 2B shows the distal end of the diagnostic imaging catheter shown in FIG. 2A. 2 is a diagram showing the proximal end of the shaft body of the diagnostic imaging catheter shown in FIG. 1 and a hub member covering the proximal end of the shaft body. FIG. 5 is a perspective view showing details of a conductive ring portion and a conductive brush portion shown in FIG. 4. FIG. 5 is a cross-sectional view taken along line I-I in FIG. 4, showing the inside of an insertion passage of a hub member. FIG. 7 is a diagram showing a modified example of the conductive ring portion shown in FIG. 6; FIG. 7 is a diagram showing a modified example of the conductive ring portion shown in FIG. 6; FIG. FIG. 2 is a diagram showing a modified example of the diagnostic imaging catheter shown in FIG. 1 .

Embodiments of diagnostic imaging catheters according to the present disclosure will be illustrated and described below with reference to the drawings. The same components are designated by the same reference numerals in each drawing.

Figure 1 is a diagram showing an imaging diagnostic system 100 including an imaging diagnostic catheter 110 as one embodiment of the imaging diagnostic catheter according to the present disclosure. As shown in Figure 1, the imaging diagnostic system 100 includes the imaging diagnostic catheter 110 and an imaging diagnostic device 120. Figure 1 shows the imaging diagnostic catheter 110 connected to the imaging diagnostic device 120.

2A and 2B are diagrams showing the diagnostic imaging catheter 110 shown in FIG. 1 alone. As will be described in detail later, FIGS. 2A and 2B show different positions of the probe 10 within the sheath 20. FIG. 3 is a diagram showing the distal end (hereinafter referred to as the "distal end") of the diagnostic imaging catheter 110. FIG. 4 is a diagram showing the proximal end 13a of the shaft 13 of the diagnostic imaging catheter 110 and the hub member 32 that covers the proximal end 13a of the shaft 13. For ease of explanation, FIG. 4 shows a side view of a portion of the configuration, including the proximal end 13a of the shaft 13. The diagnostic imaging catheter 110 is configured to acquire tomographic images of a lumen, such as a blood vessel. As shown in FIG. 1, the diagnostic imaging catheter 110 is driven by being connected to a diagnostic imaging device 120. More specifically, in this embodiment, the diagnostic imaging catheter 110 is connectable to a drive unit 120a of the diagnostic imaging device 120.

The diagnostic imaging device 120 is connectable to a diagnostic imaging catheter equipped with an imaging unit including an ultrasound transmitter/receiver. The diagnostic imaging device 120 of this embodiment is connectable to a diagnostic imaging catheter that uses IVUS, as well as a dual-type diagnostic imaging catheter that uses both IVUS and optical coherence tomography (OCT) or optical frequency domain imaging (OFDI). However, in addition to a diagnostic imaging catheter equipped with an imaging unit including an ultrasound transmitter/receiver, the diagnostic imaging device 120 may also be connectable to a diagnostic imaging catheter that does not include an ultrasound transmitter/receiver but has an imaging unit including an optical transmitter/receiver. That is, the imaging diagnostic device 120 may be connectable to, for example, an imaging diagnostic catheter that uses IVUS, a dual-type imaging diagnostic catheter that uses both IVUS and OCT or OFDI, as well as an imaging diagnostic catheter that does not use IVUS but uses OCT or OFDI. The imaging diagnostic device 120 may also be capable of generating intraluminal images using at least one of ultrasound and light, depending on the imaging diagnostic catheter that is connected.

<Imaging diagnostic catheter 110>
First, the diagnostic imaging catheter 110 will be described. As shown in Fig. 3 , the diagnostic imaging catheter 110 of this embodiment is a so-called IVUS catheter in which the imaging unit 60 includes an ultrasound transmitting/receiving unit 61a but does not include an optical transmitting/receiving unit. However, the diagnostic imaging catheter according to the present disclosure is not limited to the IVUS catheter of this embodiment as long as the imaging unit 60 includes the ultrasound transmitting/receiving unit 61a. Therefore, the diagnostic imaging catheter according to the present disclosure may be, for example, a dual-type catheter in which the imaging unit includes both an ultrasound transmitting/receiving unit and an optical transmitting/receiving unit (see Fig. 9 ).

Hereinafter, the longitudinal direction of the diagnostic imaging catheter 110 will be referred to as the "longitudinal direction A." Furthermore, the side of the diagnostic imaging catheter 110 in the longitudinal direction A that is inserted into a living body will be referred to as the "distal side." Furthermore, the side of the diagnostic imaging catheter 110 in the longitudinal direction A that is operated outside the body will be referred to as the "proximal side." The direction from the proximal side to the distal side of the diagnostic imaging catheter 110 may be simply referred to as the "insertion direction A1." Furthermore, the direction from the distal end side to the proximal end side of the diagnostic imaging catheter 110 may be simply referred to as the "removal direction A2."

As shown in Figures 1 to 2B, the diagnostic imaging catheter 110 includes a probe 10, an elongated sheath 20, an inner tube 30, and an outer tube 40. Each part of the diagnostic imaging catheter 110 will be described in detail below.

[Probe 10]
3, the probe 10 includes an imaging unit 60, a shaft body 13, and an electric signal line 14 extending inside the shaft body 13. The imaging unit 60 includes an ultrasonic wave transmitting/receiving unit 61a and a housing 61b.

As shown in FIG. 3, the imaging unit 60 is fixed to the distal end of the shaft body 13. The ultrasound transmission/reception unit 61a of the imaging unit 60 includes an ultrasound transducer. The ultrasound transducer transmits ultrasound waves based on a pulse signal through a cavity within a living body, and is capable of receiving ultrasound waves reflected from the biological tissue surrounding the cavity. The ultrasound transducer may include, for example, a main body and an electrode. The main body may include a piezoelectric element. The piezoelectric element includes a piezoelectric material such as ceramics or quartz. The ultrasound transmission/reception unit 61a can transmit and receive ultrasound waves using the ultrasound transducer.

The housing 61b supports the ultrasonic transmitter/receiver unit 61a. The shaft body 13 is connected to the proximal side of the housing 61b. The housing 61b may be integrated with the shaft body 13. Therefore, the housing 61b may be directly connected to the shaft body 13 by adhesive or the like, or may be indirectly connected to the shaft body 13 via a connector or the like.

As shown in FIG. 3, a transmitting/receiving opening 61b1 is formed in the housing 61b. The transmitting/receiving opening 61b1 allows ultrasonic waves transmitted and received by the ultrasonic transmitting/receiving unit 61a to pass through. In other words, the ultrasonic transmitting/receiving unit 61a can transmit ultrasonic waves based on pulse signals into the lumen through this transmitting/receiving opening 61b1. The ultrasonic transmitting/receiving unit 61a can also receive ultrasonic waves reflected from the biological tissue surrounding the lumen through this transmitting/receiving opening 61b1.

The ultrasonic transmitter/receiver unit 61a may be supported by the housing 61b via a backing member. The backing member scatters and attenuates ultrasonic waves traveling from the ultrasonic transmitter/receiver unit 61a to the side of the housing 61b opposite the transmitter/receiver opening 61b1. There are no particular limitations on the configuration for fixing the backing member to the housing 61b. The backing member may be fixed to the housing 61b, for example, by bonding with an adhesive.

The housing 61b may be formed, for example, by cutting out a metal block or by metal injection molding (MIM).

As shown in Figures 1 to 4, the shaft body 13 extends through the interior of the sheath 20, inner tube 30, and outer tube 40. As described above, the distal end of the shaft body 13 is connected to the housing 61b of the imaging unit 60. As shown in Figure 4, the proximal end 13a of the shaft body 13 is supported by the hub member 32 (described below) that constitutes the proximal end of the inner tube 30.

More specifically, the shaft body 13 of this embodiment includes a coil shaft portion 71, a conductive connection pipe portion 72 attached to the coil shaft portion 71 and covered by a hub member 32 (described below), and a shaft connector portion 73 connectable to the drive unit 120a.

The coil shaft portion 71 of this embodiment extends from the distal end connected to the housing 61b to the proximal end connected to the shaft connector portion 73. As shown in Figures 1 to 3, the coil shaft portion 71 of this embodiment extends in the longitudinal direction A within the sheath 20. As shown in Figure 4, the proximal end of the coil shaft portion 71 is covered by the hub member 32, which will be described later.

The coil shaft portion 71 may be configured, for example, as a multi-layer coil with different winding directions around the axis. Examples of coil materials include stainless steel and Ni-Ti (nickel-titanium) alloy. By using such a coil shaft portion 71, it is possible to improve shielding and reduce the effects of noise generated by the electrical signal lines 14, even if the two electrical signal lines 14 are configured as twisted pair cables, as described below.

The connecting pipe portion 72 is integrally attached to the outer peripheral surface of the coil shaft portion 71. The proximal end of the connecting pipe portion 72 is connected to the shaft connector portion 73, just like the coil shaft portion 71.

The shaft connector portion 73 is connected to the proximal side of the coil shaft portion 71 and the connecting pipe portion 72. The shaft connector portion 73 is also covered by the hub member 32, which will be described later. The shaft body 13 is rotatable in the circumferential direction C when the shaft connector portion 73 is connected to the drive unit 120a (see Figure 1) and driven to rotate by the drive unit 120a. Here, "circumferential direction C" refers to the direction around the central axis O of the shaft body 13.

As will be described in more detail below, in this embodiment the connection pipe portion 72 forms a conductive ring portion 80 (see Figures 4 to 6, etc.).

As shown in FIG. 3 , the electrical signal line 14 extends within the shaft body 13. Specifically, the electrical signal line 14 extends in the longitudinal direction of the shaft body 13 (the same direction as the longitudinal direction A) through a hollow portion 13b defined within the shaft body 13. More specifically, the electrical signal line 14 extends through a hollow portion 13b defined within the coil shaft portion 71 of the shaft body 13, and is electrically connected to the connecting pipe portion 72, which serves as the conductive ring portion 80.

When the diagnostic imaging catheter 110 is connected to the diagnostic imaging device 120 (see FIG. 1), the electrical signal lines 14 electrically connect the ultrasound transmission/reception unit 61a of the imaging unit 60 to the diagnostic imaging device 120 (see FIG. 1) via the conductive ring portion 80 and conductive brush portion 81 (described below). Multiple electrical signal lines 14 are provided, and each is connected to an electrode of the ultrasound transmission/reception unit 61a of the imaging unit 60. The multiple electrical signal lines 14 may be configured, for example, as a twisted pair cable in which two electrical signal lines 14 are twisted together. Each electrical signal line 14 may be a flexible, thin wire member with an outer diameter greater than 0 mm and equal to or less than 0.1 mm. Each electrical signal line 14 may be configured, for example, as a conductor and a covering made of an insulating material that covers the conductor.

[Sheath 20]
The sheath 20 is an elongated member that is inserted into a lumen such as a blood vessel. The sheath 20 is located distal to a hub member 32, which will be described later. As shown in Figures 1 to 3, the sheath 20 houses the probe 10 therein. That is, the sheath 20 houses the ultrasound transmitting/receiving unit 61a, the housing 61b, the electric signal line 14, and the shaft body 13 therein.

More specifically, as shown in Figures 1 to 3, the sheath 20 comprises a main body portion 20a and a guidewire insertion portion 20b. A first hollow portion 21a is defined within the main body portion 20a. A second hollow portion 21b is defined within the guidewire insertion portion 20b. The first hollow portion 21a of the main body portion 20a houses the probe 10. The probe 10 can move back and forth in the longitudinal direction A within the first hollow portion 21a. A guidewire W can be inserted into the second hollow portion 21b of the guidewire insertion portion 20b. As shown in Figure 3, the guidewire insertion portion 20b may be provided with a contrast marker portion 23 that is radiopaque. The contrast marker portion 23 can be formed, for example, from a metal pipe or coil that is highly radiopaque, such as platinum, gold, iridium, or tungsten. Additionally, the tubular guidewire insertion portion 20b shown in Figure 3 is adjacent to the distal end of the tubular main body portion 20a so that they are parallel to each other. The main body portion 20a and the guidewire insertion portion 20b may be formed, for example, by joining different tubular members together by heat fusion or the like.

As shown in FIG. 3, a communication hole 22a1 is formed at the distal end of the main body 20a, connecting the inside and outside of the first hollow portion 21a. A reinforcing member 22 for firmly joining and supporting the guidewire insertion portion 20b may be provided at the distal end of the main body 20a. The reinforcing member 22 has a communication passage 22a formed therein, which connects the inside of the first hollow portion 21a, located proximal to the reinforcing member 22, with the communication hole 22a1. However, the reinforcing member 22 need not be provided at the distal end of the main body 20a.

The communication hole 22a1 is a priming fluid discharge hole for discharging the priming fluid. When using the diagnostic imaging catheter 110, a priming process is performed in which the priming fluid is filled into the main body 20a of the sheath 20. When performing the priming process, the priming fluid is released to the outside through the communication hole 22a1, allowing gases such as air to be discharged from the main body 20a of the sheath 20 along with the priming fluid.

The sheath 20 and reinforcing member 22 are preferably formed from a flexible material, but the material is not particularly limited. Examples of constituent materials include various thermoplastic elastomers such as styrene-based, polyolefin-based, polyurethane-based, polyester-based, polyamide-based, polyimide-based, polybutadiene-based, trans-polyisoprene-based, fluororubber-based, and chlorinated polyethylene-based materials. Combinations of one or more of these (polymer alloys, polymer blends, laminates, etc.) can also be used. Additionally, a hydrophilic lubricating coating layer that exhibits lubricity when wet may be disposed on the outer surface of the sheath 20.

[Inner tube 30 and outer tube 40]
The inner tube 30 and the outer tube 40 have a telescopic structure, that is, the inner tube 30 is relatively movable in the longitudinal direction A within the outer tube 40, as shown in Figures 2A and 2B.

As shown in Figures 1, 2A, 2B, and 4, the inner tube 30 comprises an inner tube body 31 and a hub member 32. The inner tube body 31 is inserted within the outer tube 40 so as to be able to move back and forth in the longitudinal direction A. The hub member 32 is connected to the proximal side of the inner tube body 31.

As shown in FIG. 4, the shaft body 13 extends inside the inner tube main body 31 and the hub member 32. The proximal end 13a of the shaft body 13 is covered by the hub member 32. As shown in FIG. 4, the proximal end 13a of the shaft body 13 in this embodiment includes a connecting pipe portion 72 and a shaft connector portion 73. In other words, the connecting pipe portion 72 and the shaft connector portion 73 in this embodiment are covered by the hub member 32.

The hub member 32 also supports the shaft body 13 so that it can rotate relatively. Specifically, the hub member 32 supports the shaft body 13 so that it can rotate relatively in the circumferential direction C.

More specifically, as shown in FIG. 4, the hub member 32 of this embodiment defines an insertion passage 51 through which the shaft body 13 can be inserted. When the shaft body 13 is inserted into the insertion passage 51, the hub member 32 supports the shaft body 13 in the radial direction B. Here, "radial direction B" refers to the radial direction of an imaginary circle centered on the central axis O of the shaft body 13 in a cross section perpendicular to the central axis O of the shaft body 13.

The hub member 32 of this embodiment comprises a hub body 32a, a bearing 32b, and a seal portion 32c. The hub body 32a defines an insertion passage 51 extending along the longitudinal direction A. The bearing 32b is fitted into the insertion passage 51 of the hub body 32a. The bearing 32b defines a through-hole 32b1 that penetrates in the longitudinal direction A. The shaft body 13 of this embodiment is inserted into the through-hole 32b1 of the bearing 32b in the insertion passage 51, and is supported in the radial direction B by the bearing 32b. More specifically, the shaft body 13 of this embodiment is supported in the radial direction B by the bearing 32b, with the outer surface of the connection pipe portion 72 contacting and supported by the inner surface of the bearing 32b that defines the through-hole 32b1.

In addition to the insertion passage 51, the hub member 32 of this embodiment defines an injection passage 52 therein. More specifically, in this embodiment, the hub body 32a of the hub member 32 defines the insertion passage 51 and the injection passage 52 therein. The injection passage 52 communicates with the insertion passage 51 at a communication portion 53 between the distal end 51a and proximal end 51b of the insertion passage 51, and is a space through which liquid can be injected into the insertion passage 51 from the outside. The seal portion 32c closes the insertion passage 51 around the shaft body 13 at a position proximal to the communication portion 53 of the insertion passage 51. More specifically, the seal portion 32c of this embodiment surrounds the shaft body 13 at a position proximal to the communication portion 53 of the insertion passage 51. The seal portion 32c of this embodiment closes the insertion passage 51 together with the bearing 32b around the shaft body 13. However, the seal portion 32c is not limited to a configuration that cooperates with the bearing 32b to close the insertion passage 51. The seal portion 32c may, for example, be configured to block the gap in the insertion passage 51 around the shaft body 13 by itself. In other words, "the seal portion closes the insertion passage around the shaft body" means that the seal portion, either by itself or in cooperation with another portion, closes the insertion passage around the shaft body. The provision of such a seal portion 32c prevents liquid injected into the insertion passage 51 through the injection path 52 from flowing proximal to the seal portion 32c. The seal portion 32c in this embodiment may be configured, for example, as an O-ring, X-ring, or the like.

The hub member 32 of this embodiment also includes a connector portion 55. The connector portion 55 is connectable to a drive unit 120a (see FIG. 1) that can drive the shaft body 13 so as to rotate the shaft body 13 relative to the hub member 32. More specifically, the hub main body 32a of this embodiment includes a main body portion 32a1 that defines the insertion passage 51 therein, and a port portion 32a2 that protrudes from the main body portion 32a1 in the radial direction B and defines the injection path 52 therein. The connector portion 55 is provided on the main body portion 32a1. More specifically, the connector portion 55 is configured as a cylindrical portion that includes the proximal end of the main body portion 32a1, which serves as the proximal end of the hub member 32. As shown in FIG. 1, a tube member 200 can be connected to the port portion 32a2. As shown in FIGS. 1 to 2B and 4, the port portion 32a2 is located distal to the connector portion 55.

As will be described in more detail below, as shown in FIG. 4, the hub member 32 includes a conductive brush portion 81 that contacts the conductive ring portion 80 of the shaft body 13. In this embodiment, the conductive brush portion 81 is held by a brush holder 82 fixed to the hub main body 32a. The hub member 32 in this embodiment also includes an electrical contact portion 83 that is held by the connector portion 55 and electrically connected to the drive unit 120a when the connector portion 55 is connected to the drive unit 120a. The conductive brush portion 81 is electrically connected to the electrical contact portion 83 via a conductive member 84 held by the main body portion 32a1 of the hub main body 32a. In other words, the conductive brush portion 81 is electrically connected to the electrical contact portion 83.

As shown in Figures 1 to 2B, the outer tube 40 is fixed to the proximal end of the sheath 20. In this embodiment, the outer tube 40 comprises an outer tube main body 41, a distal connector 42, and a proximal connector 43. The outer tube main body 41 is located radially outside the inner tube main body 31, and the inner tube main body 31 moves back and forth within the outer tube main body 41. The distal connector 42 connects the proximal end of the main body 20a of the sheath 20 to the distal end of the outer tube main body 41. The proximal connector 43 is fixed to the proximal end of the outer tube main body 41.

The shaft body 13 and electrical signal line 14 of the probe 10 described above extend from a position within the main body portion 20a of the sheath 20, through the outer tube 40 connected to the proximal side of the main body portion 20a, to a position within the hub member 32 of the inner tube 30.

The probe 10 and inner tube 30 are connected to each other so that they can move forward and backward together in the longitudinal direction A. Therefore, for example, when the inner tube 30 is pushed in the insertion direction A1, the inner tube 30 is pushed into the outer tube 40 in the insertion direction A1. When the inner tube 30 is pushed into the outer tube 40 in the insertion direction A1, the probe 10 connected to the inner tube 30 moves in the insertion direction A1 within the main body portion 20a of the sheath 20. This results in the pushed-in state shown in FIG. 2A. When the inner tube 30 is pulled in the withdrawal direction A2 from the pushed-in state shown in FIG. 2A, the inner tube 30 is withdrawn from the outer tube 40 in the withdrawal direction A2. When the inner tube 30 is withdrawn from the outer tube 40 in the withdrawal direction A2, the probe 10 connected to the inner tube 30 moves in the withdrawal direction A2 within the main body portion 20a of the sheath 20. This results in the withdrawn state shown in FIG. 2B.

As shown in FIG. 1, when the hub member 32 of the inner tube 30 of the diagnostic imaging catheter 110 is connected to the drive unit 120a of the diagnostic imaging device 120, the drive unit 120a can move the probe 10 and the inner tube 30 in the removal direction A2 while rotating the probe 10 from the pushed-in state shown in FIG. 2A to the pulled-out state shown in FIG. 2B. Hereinafter, this operation may be referred to as the "pull-back imaging operation." Based on the ultrasound signals acquired by the ultrasound transmission/reception unit 61a of the imaging unit 60 during this pull-back imaging operation, the diagnostic imaging device 120 can generate a tomographic image of a lumen, such as a blood vessel, as an intraluminal image over a predetermined range in the longitudinal direction A.

<Imaging diagnostic device 120>
Next, details of the diagnostic imaging device 120 will be described. As shown in Fig. 1, the diagnostic imaging device 120 includes a drive unit 120a, a control unit 120b, and a display unit 120c that can display an image generated by the control unit 120b based on the ultrasonic and light reception signals received from the diagnostic imaging catheter 110.

The drive unit 120a includes a first drive motor 121, which is a power source for rotating the probe 10 (see Figure 2A, etc.) of the diagnostic imaging catheter 110 in the circumferential direction C, a second drive motor 122, which is a power source for moving the probe 10 and inner tube 30 (see Figure 2A, etc.) in the longitudinal direction A, and a ball screw 123.

In the diagnostic imaging catheter 110 of this embodiment, the connector portion 55 of the hub member 32 is configured to be connectable to the drive unit 120a. When the connector portion 55 of the hub member 32 is connected to the drive unit 120a (see FIG. 1), the first drive motor 121 can rotationally drive the shaft connector portion 73 of the shaft body 13. In other words, the imaging unit 60 of the diagnostic imaging catheter 110 is rotationally driven by the first drive motor 121 via the shaft body 13, and can rotate in the circumferential direction C.

Furthermore, as shown in FIG. 1, the rotational motion of the second drive motor 122 is converted into axial motion, for example, by a ball screw 123 connected to the second drive motor 122. In this way, the drive device 120a can perform a pull-back imaging operation in which the probe 10 of the diagnostic imaging catheter 110 is rotated by the first drive motor 121 while the second drive motor 122 moves the probe 10 and inner tube 30 in the removal direction A2.

The control device 120b includes a processor, such as a general-purpose processor such as a CPU (central processing unit) or MPU (micro processing unit), or a dedicated processor specialized for specific processing. The control device 120b executes processing related to the operation of the imaging diagnostic device 120 while controlling each component of the imaging diagnostic device 120. Specifically, the control device 120b controls the operation of the first drive motor 121 and second drive motor 122 of the drive device 120a. As described above, the control device 120b is capable of generating an intraluminal image based on the ultrasound reception signal received from the imaging diagnostic catheter 110. Furthermore, the control device 120b controls the display device 120c to display the generated intraluminal image on the display device 120c. The control device 120b may further include a storage unit, such as a ROM (read-only memory) or a RAM (random access memory).

The display device 120c is, for example, a display. The display device 120c may be, for example, an LCD, an organic EL display, or an HMD. "LCD" is an abbreviation for Liquid Crystal Display. "EL" is an abbreviation for Electro Luminescence. "HMD" is an abbreviation for Head-Mounted Display.

As shown in FIG. 1, in the diagnostic imaging device 120, the driving device 120a and the control device 120b are electrically connected. In the diagnostic imaging device 120, the display device 120c and the control device 120b are also electrically connected. The driving device 120a, the control device 120b, and the display device 120c may be configured as separate devices electrically connected via cables, or may be incorporated into a single device.

Furthermore, the imaging diagnostic device 120 is not limited to the configuration shown in this embodiment, and may be configured to further include an external input unit such as a keyboard, for example.

<<Conductive Ring Portion 80 and Conductive Brush Portion 81>>
Next, the conductive ring portion 80 and the conductive brush portion 81 will be described. As shown in Fig. 4, the diagnostic imaging catheter 110 includes the conductive ring portion 80 and the conductive brush portion 81. More specifically, the proximal end portion 13a of the shaft body 13 includes the conductive ring portion 80 that is electrically connected to the electrical signal line 14. In addition, the hub member 32 includes the conductive brush portion 81 that contacts the conductive ring portion 80.

As shown in Figure 5, the conductive ring portion 80 in this embodiment is the connecting pipe portion 72 of the shaft body 13. The conductive brush portion 81 of the hub member 32 is in contact with the connecting pipe portion 72 of the rotating shaft body 13 so as to slide against the connecting pipe portion 72.

By providing the diagnostic imaging catheter 110 with a conductive ring portion 80 and a conductive brush portion 81, physical twisting between the probe 10, which acts as a rotating body, and the inner tube 30, which acts as a stationary body, can be suppressed while maintaining electrical connection between them.

More specifically, the conductive ring portion 80 is electrically connected to the ultrasound transmission/reception unit 61a (see FIG. 3) of the imaging unit 60 via the electrical signal line 14. Furthermore, the conductive brush portion 81 is electrically connected to the driving unit 120a when the diagnostic imaging catheter 110 is connected to the driving unit 120a (see FIG. 1). Therefore, when the diagnostic imaging catheter 110 is connected to the driving unit 120a (see FIG. 1), the ultrasound transmission/reception unit 61a (see FIG. 3) of the imaging unit 60 is electrically connected to the driving unit 120a via the conductive ring portion 80 and the conductive brush portion 81. Furthermore, the probe 10 including the conductive ring portion 80 is driven to rotate by the first driving motor 121 of the driving unit 120a. In other words, the conductive ring portion 80 can rotate together with the imaging unit 60 (see FIG. 3) by the first driving motor 121. At this time, the hub member 32 connected to the driving unit 120a does not rotate together with the imaging unit 60 (see FIG. 3). The conductive brush portion 81 of the hub member 32 slides against the rotating conductive ring portion 80. In other words, even when the imaging unit 60 (see Figure 3) rotates, the conductive ring portion 80 and conductive brush portion 81 can maintain electrical connection between the imaging unit 60 (see Figure 3) and the drive unit 120a.

The material constituting the connecting pipe portion 72 as the conductive ring portion 80 is not particularly limited as long as it is a conductive material, but may be, for example, a metallic material such as bronze, brass, silver, or gold-based alloy.

As shown in Figures 5 and 6, the conductive brush part 81 of this embodiment includes a pair of brushes 81a, 81b arranged in opposing positions in the radial direction B, sandwiching the connecting pipe part 72 serving as the conductive ring part 80. In this embodiment, as shown in Figure 5, three pairs of brushes 81a, 81b are arranged spaced apart in the longitudinal direction A, but this configuration is not limited to this. The number of pairs of brushes 81a, 81b arranged spaced apart in the longitudinal direction A may be, for example, four or more.

Figures 7 and 8 show modified examples of the conductive ring portion 80. As shown in Figure 7, the shaft body 113 includes a coil shaft portion 71, a connection pipe portion 72 that is covered by a hub member 32 and attached to the coil shaft portion 71, and a ring body 174 that is supported on the outer surface of the connection pipe portion 72 and has lower electrical resistance than the layer that forms the outer surface of the connection pipe portion 72. In the example shown in Figure 7, this ring body 174 forms the conductive ring portion 80. Multiple ring bodies 174 may be arranged, for example, spaced apart in the longitudinal direction A.

As shown in FIG. 7, the connecting pipe section 72 may be constructed from a single layer. In other words, the layer that constitutes the outer surface of the connecting pipe section 72 shown in FIG. 7 refers to the single layer that constitutes the connecting pipe section 72. The connecting pipe section 72 shown in FIG. 7 may be constructed from, for example, a resin material serving as an insulating material. Specifically, the connecting pipe section 72 may be constructed from, for example, a resin material such as polycarbonate or FRP-based resin.

The material constituting the ring body 174 shown in FIG. 7 is not particularly limited as long as it has a lower electrical resistance than the connecting pipe portion 72, but may be, for example, a metal material such as bronze, brass, silver, or gold alloy. The ring body 174 may be formed, for example, from a coating film formed on the outer surface of the connecting pipe portion 72 by vapor deposition or the like.

Furthermore, as shown in FIG. 8, the connecting pipe portion 72 of the shaft body 113 may be composed of multiple layers. That is, the layer constituting the outer surface of the connecting pipe portion 72 shown in FIG. 8 is the outer layer 72b laminated on the outer surface of the inner layer 72a. In such a case, the inner layer 72a may be, for example, a metal material. The outer layer 72b may be, for example, an insulating resin material. Specifically, the material constituting the outer layer 72b of the connecting pipe portion 72 may be, for example, a resin material such as polycarbonate or FRP-based resin. The ring body 174 shown in FIG. 8 may be made of a material that has lower electrical resistance than the outer layer 72b of the connecting pipe portion 72. The material constituting the ring body 174 shown in FIG. 8 may be, for example, a metal material such as bronze, brass, silver, or gold-based alloy.

Furthermore, as shown in FIG. 4, the conductive ring portion 80 and conductive brush portion 81 in this embodiment are preferably arranged proximal to the seal portion 32c. In this manner, the conductive ring portion 80 and conductive brush portion 81 can be arranged in a position where the liquid injected from the injection path 52 into the insertion passage 51 does not flow in, thereby preventing unintended electrical conduction between the conductive brush portions 81 through the liquid. Furthermore, for example, when the conductive ring portion 80 is formed by the ring body 174 shown in FIGS. 7 and 8 and multiple conductive ring portions 80 are arranged spaced apart in the longitudinal direction A, unintended electrical conduction between these multiple conductive ring portions 80 through the liquid can also be prevented.

Furthermore, as shown in FIG. 4, the conductive ring portion 80 and conductive brush portion 81 of this embodiment are disposed distally of the connector portion 55 of the hub member 32. This prevents the connector portion 55 of the hub member 32, which is connected to the drive unit 120a (see FIG. 1), from becoming a complex configuration due to the arrangement of the conductive ring portion 80 and conductive brush portion 81. Furthermore, as shown in FIG. 4, the conductive ring portion 80 and conductive brush portion 81 of this embodiment are also disposed distally of the shaft connector portion 73 of the shaft body 13. This prevents the shaft connector portion 73 of the shaft body 13, which is connected to the drive unit 120a (see FIG. 1), from becoming a complex configuration due to the arrangement of the conductive ring portion 80 and conductive brush portion 81.

The diagnostic imaging catheter according to the present disclosure is not limited to the specific configurations shown in the above-described embodiments and modifications, and various modifications, alterations, and combinations are possible without departing from the scope of the claims. The diagnostic imaging catheter 110 of the above-described embodiment is a so-called IVUS catheter. However, as shown in FIG. 9 , it may be a dual-type diagnostic imaging catheter 210 in which the imaging unit 60 includes an optical transceiver 61c in addition to an ultrasound transceiver 61a. In the diagnostic imaging catheter 210 shown in FIG. 9 , the optical transceiver 61c is supported by the housing 61b together with the ultrasound transceiver 61a. As shown in FIG. 9 , the optical transceiver 61c may include, for example, a ball lens 61c1. The diagnostic imaging catheter 210 shown in FIG. 9 also includes an optical signal line 15 optically connected to the optical transceiver 61c. The optical signal line 15 may be, for example, an optical fiber. As shown in FIG. 9 , the optical signal line 15 extends within the shaft body 13 together with the electrical signal line 14. The optical signal line 15 extends from the position where it is optically connected to the optical transmitter/receiver 61c to the shaft connector portion 73 of the shaft body 13. When the hub member 32 is connected to the drive unit 120a (see FIG. 1), the optical signal line 15 is optically connected to the drive unit 120a. In this way, the diagnostic imaging catheter according to the present disclosure may be a dual-type diagnostic imaging catheter 210 as shown in FIG. 9.

This disclosure relates to a catheter for diagnostic imaging.

10: Probe 13, 113: Shaft body 13a: Proximal end portion of shaft body 13b: Hollow portion of shaft body 14: Electric signal line 15: Optical signal line 20: Sheath 20a: Main body portion 20b: Guide wire insertion portion 21a: First hollow portion 21b: Second hollow portion 22: Reinforcing member 22a: Communication passage 22a1: Communication hole 23: Radiopaque marker portion 30: Inner tube 31: Inner tube main body 32: Hub member 32a: Hub main body 32a1: Main body portion 32a2: Port portion 32b: Shaft Receiver 32b1: Through-hole 32c: Seal portion 40: Outer tube 41: Outer tube main body 42: Distal connector 43: Proximal connector 51: Insertion passage 51a: Distal end of insertion passage 51b: Proximal end of insertion passage 52: Injection path 53: Communication portion 55: Connector portion 60: Imaging portion 61a: Ultrasonic transmitting/receiving portion 61b: Housing 61b1: Transmitting/receiving opening 61c: Optical transmitting/receiving portion 61c1: Ball lens 71: Coil shaft portion 72: Connection pipe portion (an example of a conductive ring portion)
72a: inner layer 72b: outer layer 73: shaft connector portion 80: conductive ring portion 81: conductive brush portions 81a, 81b: brush 82: brush holding member 83: electrical contact portion 84: conductive member 100: diagnostic imaging system 110, 210: diagnostic imaging catheter 120: diagnostic imaging device 120a: drive device 120b: control device 120c: display device 121: first drive motor 122: second drive motor 123: ball screw 174: ring body (an example of a conductive ring portion)
200: Tube member A: Longitudinal direction A1: Insertion direction A2: Removal direction B: Radial direction C: Circumferential direction O: Central axis of shaft body W: Guide wire

Claims (8)

an ultrasonic transmitting and receiving unit;
a housing supporting the ultrasonic transmitter/receiver;
an electric signal line electrically connected to the ultrasonic transmitting/receiving unit;
a shaft body connected to a proximal side of the housing;
a hub member that covers a proximal end of the shaft body and supports the shaft body so that it can rotate relatively,
the proximal end of the shaft body includes a conductive ring portion electrically connected to the electrical signal line;
The hub member includes a conductive brush portion that contacts the conductive ring portion. The shaft body is
A coil shaft portion;
a conductive connection pipe portion that is covered by the hub member and attached to the coil shaft portion,
The diagnostic imaging catheter according to claim 1 , wherein the conductive ring portion is the connecting pipe portion. The shaft body is
A coil shaft portion;
a connecting pipe portion that is covered by the hub member and attached to the coil shaft portion;
a ring body supported on the outer surface of the connecting pipe section and having a lower electrical resistance than a layer constituting the outer surface of the connecting pipe section,
The diagnostic imaging catheter according to claim 1 , wherein the conductive ring portion is the ring body. The diagnostic imaging catheter according to claim 3, wherein the layer constituting the outer surface of the connecting pipe section is formed from an insulating material. A diagnostic imaging catheter according to any one of claims 1 to 4, wherein the electrical signal line extends in the longitudinal direction of the shaft body through a hollow portion defined inside the shaft body. The hub member is
an insertion passage through which the shaft body is inserted;
an injection path that communicates with the insertion passage at a communication portion between the distal end and the proximal end of the insertion passage and that allows a liquid to be injected into the insertion passage from the outside;
the hub member includes a seal portion that closes the insertion passage around the shaft body at a position in the insertion passage that is closer to the proximal side than the communication portion,
5. The diagnostic imaging catheter according to claim 1, wherein the conductive ring portion of the shaft body and the conductive brush portion of the hub member are disposed proximal to the seal portion. the hub member includes a connector portion connectable to a drive device that can drive the shaft body so as to rotate the shaft body relative to the hub member,
5. The diagnostic imaging catheter according to claim 1, wherein the conductive ring portion of the shaft body and the conductive brush portion of the hub member are disposed distally of the connector portion. 5. The diagnostic imaging catheter according to claim 1, further comprising a sheath that houses the ultrasound transmitting and receiving unit, the housing, the electrical signal line, and the shaft body, on the distal side of the hub member.