JP2023010448A - Catheter for image diagnosis - Google Patents

Abstract

To provide a catheter for image diagnosis in which a drive shaft hardly buckles not only in an outer tube but also in an inner tube in a pushing operation.SOLUTION: A catheter for image diagnosis includes: an outer tube; a support tube provided more inward in the radial direction than the outer tube; a drive shaft provided more inward in the radial direction than the support tube; and an inner tube provided more inward in the radial direction than the outer tube, and more outward in the radial direction than the support tube, which can move relative to the outer tube and the support tube integrally with the drive shaft in the axial direction. The inner tube includes a part for forming a plurality of flow passages, which forms a central flow passage and one or more flow passages more outward in the radial direction than the central flow passage.SELECTED DRAWING: Figure 5A

Description

The present disclosure relates to diagnostic imaging catheters.

A diagnostic imaging catheter generally has a pull-back mechanism at its proximal end for changing the relative position of the sheath and the drive shaft in order to continuously observe cross-sections within the body cavity. and an inner tube provided radially inward of the outer tube and radially outward of the drive shaft and axially movable relative to the outer tube and integrally with the drive shaft. .

If the drive shaft buckles inside the outer tube during the pushing operation of pushing the inner tube into the outer tube with respect to the pull-back mechanism, there is a risk that the drive shaft will be twisted and broken when the drive shaft is rotationally driven. For this reason, in the pullback mechanism described in Patent Document 1, for example, in order to suppress the buckling of the drive shaft during the pushing operation, a support tube that is axially movable integrally with the outer tube is arranged radially outward of the drive shaft. Moreover, it is provided radially inward of the inner pipe.

Japanese Patent No. 4672188

However, with the support tube as described in Patent Literature 1, it is difficult to prevent the drive shaft from buckling inside the inner tube during the pushing operation.

Accordingly, an object of the present disclosure is to provide a diagnostic imaging catheter in which the drive shaft is less likely to buckle not only in the outer tube but also in the inner tube during a pushing operation.

An imaging catheter according to one aspect of the present disclosure includes an outer tube, a support tube provided radially inward of the outer tube, a drive shaft provided radially inward of the support tube, and the outer tube. an inner tube provided radially inward of and radially outward of the support tube and axially movable relative to the outer tube and the support tube and integrally with the drive shaft. and the inner tube has a plurality of channel forming portions forming a central channel and one or more channels radially outside the central channel.

As one embodiment of the present disclosure, in the diagnostic imaging catheter, the plurality of flow path forming portions overlaps the support tube when viewed in the radial direction in the most retracted state in which the inner tube is pulled out from the outer tube. A diagnostic imaging catheter having a portion that does not

As one embodiment of the present disclosure, in the diagnostic imaging catheter, the plurality of flow path forming portions overlaps the support tube when viewed in the radial direction in the most retracted state in which the inner tube is pulled out from the outer tube. An imaging diagnostic catheter having a portion for diagnosing.

As one embodiment of the present disclosure, the diagnostic imaging catheter is a diagnostic imaging catheter in which the one or more flow paths are a plurality of flow paths arranged in a circumferential direction.

As one embodiment of the present disclosure, the diagnostic imaging catheter is a diagnostic imaging catheter in which the plurality of channel forming portions have a porous structure.

As an embodiment of the present disclosure, in the diagnostic imaging catheter, the multiple channel forming portion includes an inner wall forming the central channel, one or more connecting portions connecting the inner wall to the tube main body, A diagnostic imaging catheter comprising:

According to the present disclosure, it is possible to provide a diagnostic imaging catheter in which the drive shaft is less likely to buckle not only in the outer tube but also in the inner tube during a pushing operation.

FIG. 2 is a plan view showing a state in which an external device is connected to the diagnostic imaging catheter as the first embodiment; 2 is a side view showing the diagnostic imaging catheter shown in FIG. 1 in the most advanced state before pullback operation; FIG. 2 is a side view showing the diagnostic imaging catheter shown in FIG. 1 in the most retracted state after a pullback operation; FIG. FIG. 2 is a cross-sectional view showing the distal end portion of the diagnostic imaging catheter shown in FIG. 1; FIG. 2 is a cross-sectional view showing the proximal end portion of the diagnostic imaging catheter shown in FIG. 1; 2 is a cross-sectional view showing the pullback mechanism of the diagnostic imaging catheter shown in FIG. 1 in the most retracted state; FIG. 2 is a cross-sectional view showing the pullback mechanism of the diagnostic imaging catheter shown in FIG. 1 in the most advanced state; FIG. FIG. 5B is a cross-sectional view taken along line AA of FIG. 5A; FIG. 6B is a cross-sectional view showing a modification of the multiple flow path forming portion shown in FIG. 6A; FIG. 6B is a cross-sectional view showing another modification of the multiple flow path forming portion shown in FIG. 6A; FIG. 6B is a cross-sectional view showing another modification of the multiple flow path forming portion shown in FIG. 6A; FIG. 6B is a cross-sectional view showing another modification of the multiple flow path forming portion shown in FIG. 6A;

Hereinafter, embodiments of the present disclosure will be illustrated in detail with reference to the drawings.

The diagnostic imaging catheter 1 according to the present embodiment shown in FIG. 1 is a dual type that uses both intravascular ultrasound (IVUS) and optical coherence tomography (OCT). The dual-type diagnostic imaging catheter 1 has three modes: a mode for acquiring a tomographic image only by IVUS, a mode for acquiring a tomographic image only by OCT, and a mode for acquiring tomographic images by both IVUS and OCT. It exists and can be used by switching between these modes. As shown in FIG. 1, a diagnostic imaging catheter 1 is connected to and driven by an external device 2 . An imaging diagnostic apparatus 3 is composed of the diagnostic imaging catheter 1 and the external device 2 .

The diagnostic imaging catheter 1 includes a sheath 4 inserted into a body cavity such as a blood vessel (a blood vessel such as a coronary artery) of a living body, an outer tube 5 connected to a proximal end of the sheath 4, and an outer tube 5 that moves forward and backward. It has an inner tube 6 that can be inserted, a unit connector 7 that connects to the proximal end of the outer tube 5 and holds the inner tube 6 so that it can advance and retreat, and a hub 8 that connects to the proximal end of the inner tube 6 . ing. The diagnostic imaging catheter 1 includes a driving shaft 9, a housing 10 fixed to the distal end of the driving shaft 9, and a signal transmitting/receiving section 11 accommodated in the housing 10 and transmitting/receiving ultrasonic and/or light signals. and an imaging core 12 . The imaging core 12 is inserted into the sheath 4 , the outer tube 5 and the inner tube 6 , and is axially movable with respect to the sheath 4 and the outer tube 5 together with the inner tube 6 .

In the present specification, the distal end means the end of the diagnostic imaging catheter 1 that is inserted into the body cavity, and the proximal end means the end that is held outside the body cavity of the diagnostic imaging catheter 1. The axial direction means the direction along the central axis O of the drive shaft 9 (that is, the direction in which the drive shaft 9 extends), the radial direction means the direction along a straight line orthogonal to the central axis O, and the circumferential direction It means the direction around the central axis O.

The drive shaft 9 extends through the sheath 4, the outer tube 5 and the inner tube 6 to the interior of the hub 8, as shown in FIG. 2A. The hub 8 , the inner tube 6 , the drive shaft 9 , the housing 10 , and the signal transmitter/receiver 11 are connected to each other so as to be axially movable integrally with respect to the sheath 4 and the outer tube 5 . Therefore, for example, when the hub 8 is pushed toward the distal end side, that is, when a pushing operation is performed, the inner tube 6 connected to the hub 8 is pushed into the outer tube 5 and the unit connector 7, and the drive shaft is pushed. 9. The housing 10 and the signal transmitting/receiving unit 11, that is, the imaging core 12 advance inside the sheath 4, that is, move to the distal side. For example, when the hub 8 is pulled toward the base end side, that is, when a pullback operation is performed, the inner tube 6 is pulled out from the outer tube 5 and the unit connector 7 as indicated by arrow A1 in FIGS. 1 and 2B. Imaging core 12 moves proximally inside sheath 4 as indicated by arrow A2.

As shown in FIG. 2A, the distal end of the inner tube 6 reaches the vicinity of the relay connector 13 when the inner tube 6 is pushed farthest toward the distal end side and is in the most advanced state. At this time, the signal transmitter/receiver 11 is positioned at the distal end of the sheath 4 (near the distal end surface of the lumen of the sheath 4). A relay connector 13 connects the sheath 4 and the outer tube 5 .

As shown in FIG. 2B, the distal end of the inner tube 6 is provided with an engaging portion 14 for preventing slippage. The locking portion 14 prevents the inner tube 6 from slipping out of the outer tube 5 . The locking portion 14 is formed on the inner wall of the unit connector 7 when the hub 8 is pulled most proximally, that is, when the inner tube 6 is most pulled out from the outer tube 5 and the unit connector 7 . It is configured to hook into place.

As shown in FIG. 3, the drive shaft 9 is an elongated hollow member, in which an electric signal line (electric cable) 15 and an optical signal line (optical fiber) 16 connected to the signal transmitter/receiver 11 are provided. are placed.

The drive shaft 9 is formed by a coil shaft. Although illustration is omitted, the coil shaft can be formed of, for example, multiple layers of coils with different winding directions. Each coil is made of metal such as stainless steel or Ni--Ti (nickel-titanium) alloy.

The signal transmission/reception unit 11 includes an ultrasonic transmission/reception unit 11a that transmits/receives ultrasonic waves and an optical transmission/reception unit 11b that transmits/receives light. The ultrasonic transmission/reception unit 11a has a transducer that transmits ultrasonic waves based on pulse signals into the body cavity and receives ultrasonic waves that have been reflected from living tissue in the body cavity. The vibrator is electrically connected via an electrical signal line 15 to an electrical connector 15a (see FIG. 4). The vibrator can be made of, for example, a piezoelectric material such as ceramics or crystal.

The light transmitting/receiving section 11b has an optical element that transmits light into the body cavity and receives light reflected from the living tissue in the body cavity. The optical element is optically connected via an optical signal line 16 to an optical connector 16a (see FIG. 4). The optical element can be formed by a lens, such as a ball lens, for example.

The signal transmitter/receiver 11 is housed inside the housing 10 . A proximal end of the housing 10 is fixed to a distal end of the drive shaft 9 . The housing 10 is formed of a metal cylindrical tube, and is provided with an opening 10a in its peripheral surface so as not to hinder the progress of signals transmitted and received by the signal transmitter/receiver 11 . The housing 10 can be formed by laser processing or the like, for example. It should be noted that the housing 10 may be formed by cutting a metal block or by MIM (metal powder injection molding).

A tip member 17 is provided at the tip of the housing 10 . The tip member 17 has a substantially hemispherical outer shape, thereby suppressing friction and catching with the inner surface of the sheath 4 . In addition, it is good also as a structure which does not provide the front-end|tip member 17. FIG.

The sheath 4 has a lumen 4a into which the drive shaft 9 is inserted so as to be advanced and retracted. A tubular guide wire insertion member 18 through which a guide wire can be passed is attached to the distal end of the sheath 4 so as to be offset from the axial center of the lumen of the sheath 4 . The sheath 4 and the guide wire insertion member 18 are joined by welding or the like. The guidewire insertion member 18 is provided with a marker 19 having X-ray imaging properties. The marker 19 is composed of a metal pipe such as Pt, Au, or the like, which is highly opaque to X-rays.

A communicating hole 20 is formed at the distal end of the sheath 4 to communicate the inside and the outside of the lumen 4a. A reinforcing member 21 that is joined to the guide wire inserting member 18 is provided at the distal end of the lumen 4 a of the sheath 4 . A through hole is formed in the reinforcing member 21 to allow the communication hole 20 to communicate with the inner lumen 4 a arranged on the proximal side of the reinforcing member 21 . Note that the reinforcing member 21 may not be provided at the distal end of the sheath 4 .

The communication hole 20 is a priming liquid discharge hole for discharging the priming liquid. When the diagnostic imaging catheter 1 is used, the priming liquid is released from the communication hole 20 to the outside during the priming process of filling the sheath 4 with the priming liquid, and the priming liquid and gas such as air are introduced into the sheath 4. can be discharged from the inside of the

A tip side portion of the sheath 4, which is a range in which the signal transmitting/receiving portion 11 moves in the axial direction of the sheath 4, forms a window portion having higher signal permeability than other portions. The sheath 4, the guide wire insertion member 18, and the reinforcing member 21 are made of a material having flexibility, and the material is not particularly limited, and examples include styrene, polyolefin, polyurethane, polyester, polyamide, Polyimide-based, polybutadiene-based, trans-polyisoprene-based, fluororubber-based, chlorinated polyethylene-based, and other thermoplastic elastomers, etc., and combinations of one or more of these (polymer alloys, polymer blends, , laminates, etc.) can also be used.

As shown in FIG. 4, the hub 8 includes a hub body 8a which has a tubular shape coaxial with the inner tube 6 and is detachably attached to the external device 2, and a hub body 8a protruding radially outward from the hub body 8a. a port 8b that communicates with the inside of the drive shaft 9; a connecting pipe 8c that is integrally attached to the outer peripheral surface of the drive shaft 9; a bearing 8d that rotatably supports the connecting pipe 8c; It includes a seal member (first seal member 8e) for preventing the priming liquid from leaking sideways, an electrical connector 15a and an optical connector 16a, and is detachably and integrally attached to the first driving section 2a of the external device 2. and a connector portion 8f. The connector portion 8f can rotate integrally with the connection pipe 8c and the drive shaft 9. As shown in FIG.

The proximal end of the inner tube 6 is integrally connected to the distal end of the hub body 8a. The drive shaft 9 is pulled out from the inner tube 6 inside the hub body 8a.

As shown in FIG. 1, the port 8b is connected to an injection device 22 for injecting a priming solution during priming. The injection device 22 has a connector 22a connected to the port 8b and a syringe (not shown) connected to the connector 22a via a tube 22b. Priming is normally done in the most retracted state (see Figures 1 and 5A).

The external device 2 comprises a first drive section 2a for rotationally driving the drive shaft 9, a second drive section 2b for moving the drive shaft 9 in the axial direction (i.e. for push/pullback operations), have. The first drive section 2a can be configured by, for example, an electric motor. The second drive section 2b can be configured by, for example, an electric motor and a linear motion conversion mechanism. The linear motion conversion mechanism can convert rotary motion into linear motion, and can be composed of, for example, a ball screw, a rack and pinion mechanism, or the like.

The operations of the first drive section 2a and the second drive section 2b are controlled by a control device 2c electrically connected thereto. The control device 2c includes a CPU (Central Processing Unit) and memory. The control device 2c is electrically connected to the display 2d.

A signal received by the ultrasonic transmission/reception unit 11a is transmitted to the control device 2c through the electrical connector 15a, subjected to predetermined processing, and displayed as an image on the display 2d. The signal received by the optical transmitter/receiver 11b is transmitted to the controller 2c through the optical connector 16a, subjected to predetermined processing, and displayed as an image on the display 2d.

At the time of diagnosis, the sheath 4 is inserted into the body cavity, and the imaging core 12 is rotationally driven at a constant rotation speed of about 1000 to 10000 rpm by the first driving section 2a of the external device 2. The imaging core 12 is retracted at a constant speed within the lumen 4a of the sheath 4 by the pullback operation by the driving portion 2b. At this time, the control device 2 c of the external device 2 causes the signal transmission/reception unit 11 to transmit and receive signals. Based on the signal received by scanning by rotating and retreating this signal, the state of the tissue around the body cavity is displayed as an image on the display 2d.

In this manner, the diagnostic imaging catheter 1 has a pull-back mechanism 23 at its proximal portion for changing the relative position between the sheath 4 and the drive shaft 9 in order to continuously observe the internal cross section of the body cavity. As shown in FIGS. 5A and 5B , the pullback mechanism 23 is provided radially inward of the outer tube 5 and radially outward of the drive shaft 9 and relatively to the outer tube 5 . and an inner tube 6 axially movable integrally with the drive shaft 9, a support tube 24 provided radially inside the inner tube 6 and radially outside the drive shaft 9, an outer tube 5 and the support tube. 24, the relay connector 13, and the unit connector 7. As shown in FIG. As described above, the relay connector 13 is integrally connected to the sheath 4 and the inner tube 6 is integrally connected to the hub 8 . The unit connector 7 is provided with a seal member (second seal member 7a) that prevents the priming liquid from leaking from between the unit connector 7 and the inner tube 6 toward the base end side.

A locking portion 14 is provided at the distal end portion of the inner tube 6 . The engaging portion 14 is configured by an enlarged diameter portion formed by enlarging the outer peripheral surface of the inner tube 6 , and the rear end surface of the engaging portion 14 protrudes radially outward from the outer peripheral surface of the inner tube 6 and It forms an annular shape centered on . The unit connector 7 has a stopper surface 7b that abuts against the rear end surface of the locking portion 14 to restrict further retraction of the inner tube 6. As shown in FIG. The inner tube 6 has a diameter dimension sufficient to give the locking portion 14 sufficient strength as a stopper.

In the pullback mechanism 23, the outer tube 5, the support tube 24, the inner tube 6 and the drive shaft 9 are coaxially provided and have a common central axis O. As shown in FIG.

The relay connector 13 has a cylindrical shape, and has a cylindrical inner peripheral surface 13a and a cylindrical inner peripheral surface 13a connected to the tip of the proximal inner peripheral surface 13a via an annular stepped portion 13b. and a distal end side inner peripheral surface 13c. The outer peripheral surface of the proximal end of the sheath 4 is joined to the distal inner peripheral surface 13c by welding or the like. The outer peripheral surface of the distal end portion of the outer tube 5 is joined to the base end side inner peripheral surface 13a by welding or the like.

The spacer 25 has a cylindrical shape, the outer peripheral surface of the spacer 25 is in contact with the inner peripheral surface of the distal end of the outer tube 5, and the inner peripheral surface of the spacer 25 is in contact with the outer peripheral surface of the distal end of the support tube 24. . The outer peripheral surface of the spacer 25 is joined to the inner peripheral surface of the distal end of the outer tube 5 by welding or the like, and the inner peripheral surface of the spacer 25 is joined to the outer peripheral surface of the distal end of the support tube 24 by welding or the like. Further, the spacer 25 is made of synthetic resin or metal, for example.

Support tube 24 may be formed, for example, from a single layer or multiple layers of coils, tubes, or the like. The support tube 24 is made of synthetic resin or metal, for example. The use of a coiled support tube 24 facilitates priming within the outer tube 5 by allowing the priming liquid to pass radially through the support tube 24 . Instead of the coil shape, the support tube 24 may be formed in a tubular shape having a notch such as a mesh shape, wholly or partially. The support tube 24 may be formed in a tubular shape without notches. In this case, in order to promote priming inside the outer tube 5, it is preferable to provide the spacer 25 with a channel through which the priming liquid passes.

In this embodiment, the inner tube 6 includes a long tubular (long cylindrical in this embodiment) pipe main body portion 6a, a plurality of flow path forming portions 6b provided radially inward of the pipe main body portion, have. The multiple channel forming portion is a portion that forms the central channel 6c and one or more channels radially outside the central channel 6c (hereinafter also referred to as the outer channel 6d). More specifically, as shown in FIG. 6A, the multiple flow path forming portion 6b has a cylindrical inner wall 6e centered on the central axis O and one or more connecting portions 6f connecting the inner wall 6e to the pipe main body portion 6a. and have In the present embodiment, each connecting portion 6f has a rib-like shape extending along the entire axial length of the inner wall 6e, and as a result, two outer flow paths 6d are formed circumferentially. Each connecting portion 6f extends, for example, along the axial direction.

The circumferential arrangement of the rib-shaped connection portions 6f is not particularly limited, and for example, as shown in FIG. By increasing the number of rib-shaped connecting portions 6f, the number of outer flow paths 6d can be increased. For example, a configuration in which four outer flow paths 6d are provided as shown in FIG. A configuration in which two outer flow paths 6d are provided can be employed. By forming a plurality of outer flow paths 6d arranged in the circumferential direction, the plurality of flow path forming portions 6b efficiently increases the rigidity of the inner tube 6, thereby reducing the thickness of the inner tube 6 and reducing the cross-sectional area of the flow path. can be increased. The plurality of outer flow paths 6d are provided so as to be point symmetrical with respect to the central axis O, but this is not the only option.

The pipe main body 6a, the inner wall 6e, and the connecting portion 6f can be integrally formed by, for example, extrusion molding. However, after forming these separately, they may be integrated with an adhesive or the like.

By providing one rib-shaped connection portion 6f, or by providing the connection portion 6f in a dot shape instead of a rib shape, a configuration in which one outer flow path 6d is provided may be adopted.

A configuration in which the multiple flow path forming portion 6b has a porous structure is also possible. For example, a part or the whole of the multiple channel forming portion 6b having the inner wall 6e and one or more connecting portions 6f may be formed of a porous material. Alternatively, as shown in FIG. 7, the plurality of flow path forming portions 6b may be constructed of a long cylindrical porous body that is in contact with the inner peripheral surface of the pipe body portion 6a. In this case, the inner peripheral surface of the porous body can form the central flow path 6c, and the many cavities inside the porous body can form the outer flow path 6d.

As shown in FIG. 5A, the multiple flow path forming portion 6b is provided over the entire axial length of the pipe body portion 6a. Therefore, when the inner tube 6 is drawn out from the outer tube 5 to the maximum retracted state (the state shown in FIG. 5A), the multiple flow path forming portion 6b is a portion that does not overlap the support tube 24 when viewed in the radial direction (hereinafter referred to as (also referred to as non-overlapping portion 6g). As a result, when the inner tube 6 and the drive shaft 9 are advanced with respect to the outer tube 5 and the support tube 24 by the pushing operation from the most retracted state, the drive shaft 9 is supported from the radially outer side by the support tube 24 to drive. The shaft 9 is restrained from buckling inside the outer tube 5 (for example, as indicated by the two-dot chain line in FIG. 5A), and the drive shaft 9 is positioned inside the inner wall 6e of the non-overlapping portion 6g of the multiple passage forming portion 6b. By supporting the driving shaft 9 from the outside in the radial direction by the peripheral surface, it is possible to suppress the buckling of the drive shaft 9 inside the inner tube 6 (for example, as indicated by the two-dot chain line in FIG. 5A). Therefore, the drive shaft 9 is rotationally driven in a buckled state within the pull-back mechanism 23, and it is possible to prevent the drive shaft 9 from being twisted and broken.

As shown in FIG. 5A, the multiple flow path forming portion 6b has a portion that overlaps with the support tube 24 when viewed in the radial direction in the most retracted state (hereinafter, also referred to as an overlapping portion 6h). Therefore, when the inner tube 6 and the drive shaft 9 are advanced with respect to the outer tube 5 and the support tube 24 by the pushing operation from the most retracted state, the support tube 24 is pushed along the inner wall 6e of the overlapping portion 6h of the plurality of passage forming portions 6b. The support tube 24 can be prevented from buckling inside the inner tube 6 by being supported from the radially outer side by the inner peripheral surface. Therefore, the drive shaft 9 is rotationally driven in a buckled state within the pull-back mechanism 23, and it is possible to further prevent the drive shaft 9 from being twisted and broken. From another point of view, when the inner tube 6 and the drive shaft 9 are advanced with respect to the outer tube 5 and the support tube 24 by a pushing operation from the most retracted state, the base end portion of the support tube 24 and the tip portion of the inner tube 6 are pushed forward. It is possible to prevent interference with the push-in operation due to contact.

The multiple flow path forming portion 6b is not limited to a structure extending over the entire axial length of the pipe main body portion 6a. A configuration having the overlapping portion 6h without the 6g may also be used. In either configuration, it is possible to prevent the drive shaft 9 from being twisted and broken by the plurality of flow path forming portions 6b.

In addition, since the inner tube 6 has the outer flow path 6d, the priming liquid can easily pass through the inner tube 6 as compared with a structure in which the inner diameter of the inner tube 6 is simply reduced. Priming can be ensured.

The present disclosure is not limited to the above-described embodiments, and can be variously modified without departing from the scope of the present disclosure.

Therefore, the diagnostic imaging catheter 1 according to the embodiment described above can be modified in various ways, for example, as described below.

The diagnostic imaging catheter 1 according to the embodiment described above includes an outer tube 5, a support tube 24 provided radially inward of the outer tube 5, a drive shaft 9 provided radially inward of the support tube 24, An inner tube 6 which is provided radially inside the outer tube 5 and radially outside the support tube 24 and is axially movable relative to the outer tube 5 and the support tube 24 and integrally with the drive shaft 9 . and wherein the inner tube 6 has a plurality of flow path forming portions 6b forming a central flow path 6c and one or more flow paths (outer flow paths 6d) radially outside the center flow path 6c. Various modifications are possible as far as the diagnostic catheter 1 is concerned.

For example, without providing the spacer 25, the tip of the support tube 24 may be directly connected integrally to the relay connector 13 or the outer tube 5 with an adhesive or the like.

The pull-back mechanism 23 is not limited to the configuration in which the outer tube 5 is integrally connected to the relay connector 13 and the inner tube 6 is integrally connected to the hub 8 . may be integrally connected to the relay connector 13 .

The diagnostic imaging catheter 1 is not limited to a dual type using both IVUS and OCT, and may be a type using only IVUS or only OCT.

In the diagnostic imaging catheter 1 according to the above-described embodiment, the multiple flow path forming portion 6b is in the most retracted state in which the inner tube 6 is most pulled out of the outer tube 5, and the support tube 24 and the support tube 24 when viewed in the radial direction. It is preferable that the diagnostic imaging catheter 1 has a non-overlapping portion (non-overlapping portion 6g).

In the diagnostic imaging catheter 1 according to the above-described embodiment, the multiple flow path forming portion 6b overlaps the support tube 24 when viewed in the radial direction in the most retracted state in which the inner tube 6 is pulled out from the outer tube 5. It is preferable that the diagnostic imaging catheter 1 has a portion (overlapping portion 6h).

The diagnostic imaging catheter 1 according to the above-described embodiment is preferably the diagnostic imaging catheter 1 in which one or more flow paths (outer flow paths 6d) are a plurality of flow paths arranged in the circumferential direction.

The diagnostic imaging catheter 1 according to the above-described embodiment is preferably the diagnostic imaging catheter 1 in which the multi-channel forming portion 6b has a porous structure.

REFERENCE SIGNS LIST 1 diagnostic imaging catheter 2 external device 2a first driving unit 2b second driving unit 2c control device 2d display 3 diagnostic imaging device 4 sheath 4a lumen of sheath 5 outer tube 6 inner tube 6a tube main body 6b multiple channel forming part 6c center channel 6d outer channel 6e inner wall 6f connecting portion 6g non-overlapping portion 6h overlapping portion 7 unit connector 7a second seal member 7b stopper surface 8 hub 8a hub body 8b port 8c connection pipe 8d bearing 8e first seal member 8f connector portion 9 drive shaft 10 housing 10a opening 11 signal transmitter/receiver 11a ultrasonic transmitter/receiver 11b optical transmitter/receiver 12 imaging core 13 relay connector 13a proximal side inner peripheral surface 13b stepped portion 13c distal side inner peripheral surface 14 engaging portion 15 electric signal Wire 15a Electrical connector 16 Optical signal line 16a Optical connector 17 Tip member 18 Guide wire insertion member 19 Marker 20 Communication hole 21 Reinforcing member 22 Injection device 22a Connector 22b Tube 23 Pullback mechanism 24 Support tube 25 Spacer O Central axis

Claims (6)

an outer tube, a support tube provided radially inward of the outer tube, a drive shaft provided radially inward of the support tube, and a radially inner side of the outer tube and radially of the support tube. an inner tube mounted on the outside and axially movable relative to the outer tube and the support tube and integrally with the drive shaft;
The diagnostic imaging catheter, wherein the inner tube has a plurality of channel forming portions forming a central channel and one or more channels radially outside the central channel. 2. The diagnostic imaging catheter according to claim 1, wherein said multiple flow path forming part has a portion that does not overlap with said support tube when viewed in a radial direction in a most retracted state in which said inner tube is pulled out from inside said outer tube. . 3. The diagnostic imaging according to claim 1 or 2, wherein the multiple flow path forming part has a portion overlapping with the support tube when viewed in the radial direction in the most retracted state in which the inner tube is drawn out from the outer tube. Catheter for. The diagnostic imaging catheter according to any one of claims 1 to 3, wherein said one or more channels are a plurality of channels arranged in a circumferential direction. The diagnostic imaging catheter according to any one of claims 1 to 4, wherein the multiple channel forming portion has a porous structure. 6. The multi-channel forming portion according to any one of claims 1 to 5, wherein the multiple channel forming portion has an inner wall forming the central channel and one or more connecting portions connecting the inner wall to the pipe main body. diagnostic imaging catheter.

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