JP6949579B2 - Diagnostic imaging catheter - Google Patents

Description

The present invention relates to a diagnostic imaging catheter.

Conventionally, as a medical device used for acquiring a tomographic image for diagnosing a diseased part in a living body, an intravascular ultrasonic diagnostic method (IVUS: Intra Vascural Ultra Sound) or an optical coherence tomography method (IVUS) There are diagnostic imaging catheters used in diagnostic imaging equipment such as OCT: Optical Coherence Tomography).

The diagnostic imaging catheter includes a drive shaft provided with a signal transmission / reception unit for transmitting / receiving test waves, and a sheath having a lumen into which the drive shaft is inserted so as to be able to move forward and backward. When using a diagnostic imaging catheter, a so-called pullback operation (middle pull operation), in which the drive shaft is moved backward from the tip side to the base end side by moving the drive shaft backward while rotating, or pushing the drive shaft toward the tip side. A pushing operation is performed (see Patent Document 1 below).

Japanese Unexamined Patent Publication No. 2015-119994

The drive shaft of the diagnostic imaging catheter used in IVUS is generally configured by arranging an electric wire in the internal space of the coil shaft formed in a coil shape. Therefore, it is necessary to increase the inner diameter of the coil shaft so that the electric wire can be arranged in the internal space of the coil shaft. In this way, as the inner diameter of the coil shaft increases, the outer diameter of the coil shaft also increases. Further, as the outer diameter of the coil shaft is increased, it is necessary to increase the diameter of the sheath so that the coil shaft can move forward and backward inside the sheath. As the diameter of the sheath increases in this way, the frictional resistance increases in the living body, and there is a possibility that the diagnostic imaging catheter cannot be suitably inserted into the living body. From the above, it is desired to reduce the diameter of the drive shaft by reducing the inner diameter of the coil shaft.

On the other hand, when the diameter of the drive shaft is reduced, the rigidity of the drive shaft is lowered by simply reducing the outer diameter of the coil shaft while maintaining the inner diameter of the coil shaft. If the rigidity of the drive shaft is reduced in this way, the drive shaft may flutter when the drive shaft is rotated, and a tomographic image may not be obtained favorably.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a diagnostic imaging catheter capable of reducing the diameter of the drive shaft while suppressing a decrease in the rigidity of the drive shaft. do.

A diagnostic imaging catheter that achieves the above object has a rotatable drive shaft provided with a signal transmitting / receiving unit at a tip portion, and a sheath having a lumen into which the drive shaft is inserted so as to be able to move forward and backward. Further, the drive shaft includes a coil-shaped coil shaft composed of at least one layer, and the coil shaft has an electric wire connected to the signal transmission / reception unit and a high-rigidity wire having a higher rigidity than the electric wire. .. Further, the high-rigidity wire has a first high-rigidity wire, and the coil shaft has a stranded wire in which the electric wire and the first high-rigidity wire are twisted.
Further, the diagnostic imaging catheter that achieves the above object has a rotatable drive shaft provided with a signal transmitting / receiving unit at the tip portion, and a sheath having a lumen into which the drive shaft is inserted so as to be able to move forward and backward. Further, the drive shaft includes a coil-shaped coil shaft composed of at least one layer, and the coil shaft has an electric wire connected to the signal transmission / reception unit and a high-rigidity wire having a higher rigidity than the electric wire. .. Further, the coil shaft is formed in a coil shape in which the electric wire and the high rigidity wire are arranged in the circumferential direction in a cross-sectional view orthogonal to the axial direction of the coil shaft.

According to the diagnostic imaging catheter configured as described above, since the electric wire is included in the coil shaft, the diameter of the drive shaft should be reduced as compared with the configuration in which the electric wire is arranged in the internal space of the coil shaft. Can be done. Further, since the coil shaft has an electric wire and a high rigidity wire, it is possible to suppress a decrease in the rigidity of the drive shaft. From the above, it is possible to provide a diagnostic imaging catheter capable of reducing the diameter of the drive shaft while suppressing a decrease in the rigidity of the drive shaft.

It is a top view which shows the state which the external device is connected to the diagnostic imaging catheter which concerns on embodiment of this invention. FIG. 2A is a diagram schematically showing the overall configuration of the diagnostic imaging catheter according to the embodiment, and FIG. 2A is a side view of the diagnostic imaging catheter before the pullback operation (middle pulling operation) is performed, FIG. 2 (A). B) is a side view of the diagnostic imaging catheter when the pullback operation is performed. It is an enlarged cross-sectional view which shows the structure of the distal end side of the diagnostic imaging catheter which concerns on embodiment. It is an enlarged cross-sectional view which shows the structure of the housing and the drive shaft of the diagnostic imaging catheter which concerns on embodiment. It is sectional drawing which follows the 5-5 line of FIG. It is a schematic perspective view which shows the structure of a stranded wire. It is sectional drawing which shows the structure of a stranded wire. It is an enlarged cross-sectional view which shows the structure of the proximal end side of the diagnostic imaging catheter which concerns on embodiment. FIG. 9A is a cross-sectional view showing a state in which a diagnostic imaging catheter is inserted into a blood vessel, and FIG. 9B is a cross-sectional view showing a state in which a flash process is performed. It is a figure corresponding to FIG. 5 of the coil shaft which concerns on modification 1. FIG. It is a figure corresponding to FIG. 7 of the coil shaft which concerns on modification 1. FIG. It is a figure corresponding to FIG. 5 of the coil shaft which concerns on modification 2. It is a figure corresponding to FIG. 7 of the coil shaft which concerns on modification 2. FIG. It is a figure corresponding to FIG. 4 of the coil shaft which concerns on modification 3. It is a figure corresponding to FIG. 4 of the coil shaft which concerns on modification 4. It is a figure corresponding to FIG. 7 of the coil shaft which concerns on modification 5.

Hereinafter, embodiments of the present invention will be described with reference to the attached drawings. The following description does not limit the technical scope and meaning of terms described in the claims. In addition, the dimensional ratios in the drawings are exaggerated for convenience of explanation and may differ from the actual ratios.

FIG. 1 is a plan view showing a state in which the external device 300 is connected to the diagnostic imaging catheter 100 according to the embodiment. FIG. 2 is a diagram schematically showing the overall configuration of the diagnostic imaging catheter 100 according to the embodiment. FIG. 3 is a diagram showing a configuration on the distal end side of the diagnostic imaging catheter 100 according to the embodiment. FIG. 4 is an enlarged cross-sectional view showing the configuration of the housing 146 and the drive shaft 140 of the diagnostic imaging catheter 100 according to the embodiment. FIG. 5 is a cross-sectional view taken along the line 5-5 of FIG. 6 and 7 are views showing the configuration of the stranded wire 221. FIG. 8 is a diagram showing a configuration on the proximal end side of the diagnostic imaging catheter 100 according to the embodiment.

The diagnostic imaging catheter 100 according to the present embodiment has both functions of endovascular ultrasonic diagnosis (IVUS) and optical coherence tomography (OCT), and each function is switched or used at the same time. It is a dual type that can be used. As shown in FIG. 1, the diagnostic imaging catheter 100 is driven by being connected to an external device 300.

The configuration of the diagnostic imaging catheter 100 will be described with reference to FIGS. 1 to 8.

As shown in FIGS. 1, 2 (A), and 2 (B), the diagnostic imaging catheter 100 is generally provided on the sheath 110 inserted into the body cavity of a living body and on the proximal end side of the sheath 110. A drive shaft 140 rotatably provided in the sheath 110 having an outer tube 120, an inner shaft 130 that is movably inserted into the outer tube 120, and a signal transmission / reception unit 145 that transmits / receives signals at the tip. It has a unit connector 150 provided on the proximal end side of the outer tube 120 and configured to receive the inner shaft 130, and a hub 160 provided on the proximal end side of the inner shaft 130.

In the description of the specification, the side inserted into the body cavity of the diagnostic imaging catheter 100 is referred to as the distal end or the distal end side, and the hub 160 side provided in the diagnostic imaging catheter 100 is referred to as the proximal end or the proximal end side. The extending direction of the sheath 110 is referred to as an axial direction.

As shown in FIG. 2A, the drive shaft 140 passes through the sheath 110, the outer tube 120 connected to the base end of the sheath 110, and the inner shaft 130 inserted into the outer tube 120, and extends to the inside of the hub 160. Exists.

The hub 160, the inner shaft 130, the drive shaft 140, and the signal transmission / reception unit 145 are connected to each other so as to move forward and backward in the axial direction. Therefore, for example, when the hub 160 is pushed toward the tip side, the inner shaft 130 connected to the hub 160 is pushed into the outer pipe 120 and the unit connector 150, and the drive shaft 140 and signal transmission / reception are performed. The portion 145 moves inside the sheath 110 toward the tip end side. For example, when the hub 160 is pulled toward the proximal end side, the inner shaft 130 is pulled out from the outer tube 120 and the unit connector 150 and driven as shown by the arrow a1 in FIGS. 1 and 2B. The shaft 140 and the signal transmission / reception unit 145 move inside the sheath 110 toward the proximal end side as shown by the arrow a2.

As shown in FIG. 2A, when the inner shaft 130 is pushed most toward the tip side, the tip portion of the inner shaft 130 reaches the vicinity of the relay connector 170. At this time, the signal transmission / reception unit 145 is located near the tip of the sheath 110. The relay connector 170 is a connector that connects the sheath 110 and the outer tube 120.

As shown in FIG. 2B, a connector 131 for preventing disconnection is provided at the tip of the inner shaft 130. The disconnection prevention connector 131 has a function of preventing the inner shaft 130 from detaching from the outer pipe 120. The disconnection prevention connector 131 is provided at a predetermined position on the inner wall of the unit connector 150 when the hub 160 is pulled to the most proximal side, that is, when the inner shaft 130 is most pulled out from the outer tube 120 and the unit connector 150. It is configured to be caught in.

As shown in FIG. 3, the signal transmission / reception unit 145 includes an ultrasonic wave transmission / reception unit 145a for transmitting / receiving ultrasonic waves and an optical transmission / reception unit 145b for transmitting / receiving light. The ultrasonic transmission / reception unit 145a is arranged on the tip side of the optical transmission / reception unit 145b. The positional relationship between the ultrasonic transmission / reception unit 145a and the optical transmission / reception unit 145b may be opposite.

The ultrasonic transmission / reception unit 145a includes a vibrator, and has a function of transmitting ultrasonic waves based on a pulse signal into the body cavity and receiving ultrasonic waves reflected from biological tissues in the body cavity. The ultrasonic transmission / reception unit 145a is electrically connected to the electrode terminal 165a (see FIG. 8) via an electric wire 221a.

As shown in FIGS. 3 and 4, the upper surface of the ultrasonic transmission / reception unit 145a is inclined so that the ultrasonic waves are transmitted in the direction in which the ultrasonic waves are inclined toward the proximal end side with respect to the radial direction (upward direction in FIG. 3). And are arranged.

As the vibrator included in the ultrasonic transmission / reception unit 145a, for example, a piezoelectric material such as ceramics or quartz can be used.

The light transmission / reception unit 145b continuously transmits the transmitted measurement light into the body cavity and continuously receives the reflected light from the living tissue in the body cavity. The light transmission / reception unit 145b has a ball lens (optical element) provided at the tip of the optical fiber 250 and having a lens function for collecting light and a reflection function for reflecting light.

The signal transmission / reception unit 145 is housed inside the housing 146. The base end side of the housing 146 is connected to the drive shaft 140. The housing 146 has a shape in which an opening is provided on the outer peripheral surface of a cylindrical metal pipe so as not to hinder the progress of ultrasonic waves transmitted / received by the ultrasonic wave transmitting / receiving unit 145a and light transmitted / received by the optical transmitting / receiving unit 145b. .. The housing 146 can be formed by shaving from a metal block, MIM (metal powder injection molding), or the like.

Next, the configuration of the drive shaft 140 according to the present embodiment will be described with reference to FIGS. 3 to 7. As shown in FIGS. 3 and 4, the drive shaft 140 includes a flexible coil shaft 210 and an optical fiber 250 arranged inside the coil shaft 210.

The coil shaft 210 is composed of three layers 220, 230 and 240 arranged in layers in the radial direction, and the three layers 220, 230 and 240 are formed in a coil shape, respectively. The three layers 220, 230, and 240 are arranged so as to be the first layer 220, the second layer 230, and the third layer 240 in order from the outer side in the radial direction. Further, the coil shaft 210 generally has an electric wire 221a connected to the ultrasonic transmission / reception unit 145a and a high-rigidity wire 260 having a higher rigidity than the electric wire 221a. Further, the high-rigidity wire 260 includes a first high-rigidity wire 221b (see FIG. 6) constituting the stranded wire 221 described later and a second high-rigidity wire 222, 231 and 241 having an outer diameter larger than that of the first high-rigidity wire 221b. (See FIG. 5).

As shown in FIG. 4, the first layer 220 has a stranded wire 221 and a second high-rigidity wire 222. As shown in FIG. 5, the stranded wire 221 and the second high-rigidity wire 222 are arranged side by side in the circumferential direction in a cross-sectional view orthogonal to the axial direction. Further, in a cross-sectional view orthogonal to the axial direction, two stranded wires 221 are provided along the circumferential direction, and six second high-rigidity wires 222 are provided along the circumferential direction. In the first layer 220, the two stranded wires 221 and the six second high-rigidity wires 222 are each formed in a coil shape. The number of stranded wires 221 and the second high-rigidity wire 222 provided is not limited to the above.

As shown in FIGS. 6 and 7, the stranded wire 221 has one electric wire 221a and twelve first high-rigidity wires 221b. As shown in FIG. 5, two stranded wires 221 are provided along the circumferential direction, so that two electric wires 221a are arranged on the coil shaft 210.

The two electric wires 221a constitute a positive signal line connected to the positive electrode terminal 165a provided in the connector portion 165, which will be described later, and a negative signal line connected to the negative electrode terminal 165a. ..

The number of electric wires 221a and the number of first high-rigidity wires 221b can be adjusted from the desired strength and electrical characteristics of the stranded wire 221. For example, in order to improve the strength of the stranded wire 221 the number of the first high-rigidity wires 221b can be increased, and in order to improve the electrical characteristics of the stranded wire 221, the number of the electric wires 221a is increased. Can be done.

In the present embodiment, the electric wire 221a is composed of one copper wire coated with an insulating member (for example, PTFE). As described above, when the electric wire 221a includes one copper wire, the attenuation of the electric signal can be suitably suppressed when the electric signal received by the ultrasonic transmission / reception unit 145a is transmitted to the electrode terminal 165a. can.

As shown in FIGS. 6 and 7, the first high-rigidity wire 221b is arranged so as to surround the electric wire 221a. By arranging the first high-rigidity wire 221b so as to surround the electric wire 221a in this way, damage to the electric wire 221a can be prevented. Examples of the constituent material of the high-rigidity wire 260 include stainless steel and Ni-Ti (nickel-titanium) alloy.

The second layer 230 has a second high-rigidity wire 231 as shown in FIG. As shown in FIG. 5, eight second high-rigidity lines 231 are provided along the circumferential direction in a cross-sectional view orthogonal to the axial direction. In the second layer 230, the eight second high-rigidity wires 231 are each formed in a coil shape. The number of second high-rigidity wires 231 provided is not limited to the above. Further, as the material constituting the second high-rigidity wire 231, the same material as the above-mentioned second high-rigidity wire 222 can be used. Further, the outer diameter of the second high-rigidity wire 231 can be substantially the same as the outer diameter of the second high-rigidity wire 222.

The third layer 240 has a second high-rigidity wire 241 as shown in FIG. As shown in FIG. 5, eight second high-rigidity lines 241 are provided along the circumferential direction in a cross-sectional view orthogonal to the axial direction. In the third layer 240, the eight second high-rigidity wires 241 are each formed in a coil shape. The number of second high-rigidity wires 241 provided is not limited to the above. Further, as the material constituting the second high-rigidity wire 241, the same material as the above-mentioned second high-rigidity wire 222 can be used. Further, the outer diameter of the second high-rigidity wire 241 can be substantially the same as the outer diameter of the second high-rigidity wire 222.

With reference to FIG. 3 again, the sheath 110 includes a lumen 110a into which the drive shaft 140 is inserted so that it can move forward and backward. A guide wire insertion member 114 is attached to the tip of the sheath 110 so as to be juxtaposed with the lumen 110a provided on the sheath 110 and provided with a guide wire lumen 114a through which the guide wire W can be inserted. The sheath 110 and the guide wire insertion member 114 can be integrally formed by heat fusion or the like. The guide wire insertion member 114 is provided with a marker 115 having an X-ray contrast property. The marker 115 is composed of a metal coil having high X-ray impermeable properties such as Pt, Au, and Ir.

A communication hole 116 that communicates the inside and the outside of the lumen 110a is formed at the tip of the sheath 110. Further, a reinforcing member 117 for firmly joining and supporting the guide wire insertion member 114 is provided at the tip of the sheath 110. The reinforcing member 117 is formed with a communication passage 117a that communicates the inside of the lumen 110a arranged on the proximal end side of the reinforcing member 117 with the communication hole 116. The reinforcing member 117 may not be provided at the tip of the sheath 110.

The communication hole 116 is a priming liquid discharge hole for discharging the priming liquid. When the diagnostic imaging catheter 100 is used, a priming process is performed in which the priming liquid is filled in the sheath 110 in order to reduce the attenuation of the ultrasonic waves due to the air in the sheath 110 and efficiently transmit and receive the ultrasonic waves. When the priming process is performed, the priming liquid can be discharged to the outside from the communication hole 116, and a gas such as air can be discharged from the inside of the sheath 110 together with the priming liquid.

The tip of the sheath 110, which is the range in which the signal transmission / reception unit 145 moves in the axial direction of the sheath 110, constitutes a window portion formed so that the transparency of inspection waves such as light and ultrasonic waves is higher than that of other parts. ..

The sheath 110, the guide wire insertion member 114, and the reinforcing member 117 are made of a flexible material, and the material is not particularly limited, and examples thereof include styrene-based, polyolefin-based, polyurethane-based, polyester-based, and polyamide-based. Examples include various thermoplastic elastomers such as polyimide-based, polybutadiene-based, transpolyisoprene-based, fluororubber-based, and chlorinated polyethylene-based, and one or a combination of two or more of these (polymer alloy, polymer blend). , Laminates, etc.) can also be used. A hydrophilic lubricating coating layer that exhibits lubricity when wet can be arranged on the outer surface of the sheath 110.

As shown in FIG. 8, the hub 160 includes a hub body 161 having a hollow shape, a connector case 161a connected to the base end side of the hub body 161, a port 162 communicating with the inside of the hub body 161, and an external device. Projections 163a and 163b for determining the position (direction) of the hub 160 when connecting to the 300, a connecting pipe 164b for holding the drive shaft 140, and a bearing 164c for rotatably supporting the connecting pipe 164b. A connector portion in which a sealing member 164a for preventing priming liquid from leaking from between the connection pipe 164b and the bearing 164c toward the base end side, an electrode terminal 165a connected to the external device 300, and an optical connector 165b are arranged inside. It has 165 and.

An inner shaft 130 is connected to the tip of the hub body 161. The drive shaft 140 is pulled out from the inner shaft 130 inside the hub body 161. A protective tube 133 is arranged between the inner shaft 130 and the drive shaft 140. The protective tube 133 has a function of preventing the drive shaft 140 from being damaged due to interference between the inner shaft 130 and the drive shaft 140.

An injection device S (see FIG. 1) for injecting the priming liquid when performing the priming process is connected to the port 162. The injection device S is connected to the connector S1 connected to the port 162, the tube S2 connected to the connector S1, the three-way stopcock S3 connected to the tube S2, and the three-way stopcock S3, and the priming liquid is supplied to the port 162. A first syringe S4 and a second syringe S5 that can be injected into the tube are provided. The second syringe S5 is a syringe that has a larger capacity than the first syringe S4 and is used as an auxiliary when the amount of the priming liquid to be injected by the first syringe S4 is insufficient.

The connection pipe 164b holds the drive shaft 140 in order to transmit the rotation of the electrode terminal 165a and the optical connector 165b, which are rotationally driven by the external device 300, to the drive shaft 140. A coil shaft 210 and an optical fiber 250 are inserted inside the connecting pipe 164b.

The connector portion 165 has an electrode terminal 165a electrically connected to the electric wire 221a and an optical connector 165b connected to the optical fiber 250. The received signal in the ultrasonic transmission / reception unit 145a is transmitted to the external device 300 via the electrode terminal 165a, subjected to predetermined processing, and displayed as an image. The received signal in the optical transmission / reception unit 145b is transmitted to the external device 300 via the optical connector 165b, subjected to predetermined processing, and displayed as an image.

With reference to FIG. 1 again, the diagnostic imaging catheter 100 is connected to and driven by an external device 300.

As described above, the external device 300 is connected to the connector portion 165 provided on the base end side of the hub 160.

Further, the external device 300 has a motor 300a which is a power source for rotating the drive shaft 140 and a motor 300b which is a power source for moving the drive shaft 140 in the axial direction. The rotational motion of the motor 300b is converted into axial motion by the ball screw 300c connected to the motor 300b.

The operation of the external device 300 is controlled by the control device 301 electrically connected to the external device 300. The control device 301 includes a CPU (Central Processing Unit) and a memory as a main configuration. The control device 301 is electrically connected to the monitor 302.

Next, an example of using the diagnostic imaging catheter 100 will be described with reference to FIG. 9 and the like. FIG. 9A is a cross-sectional view showing a state in which the diagnostic imaging catheter 100 is inserted into the blood vessel 900, and FIG. 9B is a cross-sectional view showing a state in which the flash treatment is performed.

First, the user connects the injection device S for injecting the priming liquid to the port 162 with the hub 160 pulled to the most proximal side (see FIG. 2B), and pushes the pusher of the first syringe S4. Press to inject the priming solution into the lumen 110a of the sheath 110. If the amount of the priming liquid to be injected by the first syringe S4 is insufficient, the pusher of the second syringe S5 is pushed to inject the priming liquid into the lumen 110a of the sheath 110.

When the priming liquid is injected into the lumen 110a, the priming liquid is discharged to the outside of the sheath 110 through the communication passage 117a and the communication hole 116 shown in FIG. 3, and a gas such as air is discharged from the inside of the sheath 110 together with the priming liquid. Can be discharged to the outside (priming process).

After the priming process, the user connects the external device 300 to the connector portion 165 of the diagnostic imaging catheter 100 as shown in FIG. Then, the user pushes the hub 160 until it comes into contact with the base end of the unit connector 150 (see FIG. 2A), and moves the signal transmission / reception unit 145 to the tip side. In this state, as shown in FIG. 9A, the diagnostic imaging catheter 100 is inserted into the lumen 500a of the guiding catheter 500. The guiding catheter 500 is preliminarily inserted into the blood vessel 900 along the guide wire W.

Here, according to the diagnostic imaging catheter 100 according to the present embodiment, since the electric wire 221a is included in the coil shaft 210, the coil shaft 210 is compared with the configuration in which the electric wire is arranged in the internal space of the coil shaft. The inner diameter of the drive shaft 140 can be reduced, and the diameter of the drive shaft 140 can be reduced. Therefore, the diameter of the diagnostic imaging catheter 100 can also be reduced, and the diagnostic imaging catheter 100 can be suitably inserted into the lumen 500a of the guiding catheter 500.

Next, as shown in FIG. 9A, the diagnostic imaging catheter 100 is advanced along the lumen 500a and protrudes from the tip opening of the guiding catheter 500. Then, while inserting the guide wire W through the guide wire lumen 114a, the diagnostic imaging catheter 100 is further pushed along the guide wire W and inserted into the target position in the blood vessel 900.

Here, according to the diagnostic imaging catheter 100 according to the present embodiment, as described above, the diameter of the drive shaft 140 can be reduced as compared with the configuration in which the electric wire is arranged in the internal space of the coil shaft. can. Therefore, the diameter of the diagnostic imaging catheter 100 can also be reduced, and the diagnostic imaging catheter 100 can be suitably inserted into the blood vessel 900.

As the guiding catheter 500, a known guiding catheter having a port (not shown) to which a syringe (not shown) can be connected can be used at the base end.

Next, a flash treatment is performed in which the blood in the blood vessel 900 is washed away with a flash solution F1 such as a contrast medium. Similar to the priming process described above, the syringe containing the flush solution F1 is connected to the port of the guiding catheter 500, and the pusher of the syringe is pushed to inject the flush solution F1 into the lumen 500a of the guiding catheter 500. The flush fluid F1 passes through the lumen 500a of the guiding catheter 500 and is introduced into the blood vessel 900 through the tip opening thereof, as shown by the arrow C in FIG. 9B. The introduced flush liquid F1 flushes the blood around the tip of the sheath 110, and the flash liquid F1 is filled around the tip of the sheath 110.

When obtaining a tomographic image at a target position in the blood vessel 900, the signal transmission / reception unit 145 moves toward the proximal end side while rotating together with the drive shaft 140 (pullback operation). At this time, the signal transmission / reception unit 145 transmits / receives an inspection wave.

Here, according to the diagnostic imaging catheter 100 according to the present embodiment, since the coil shaft 210 has the electric wire 221a and the high rigidity wire 260, it is possible to suppress the decrease in the rigidity of the drive shaft 140. Further, the rigidity of the drive shaft 140 can be improved as compared with the case where the coil shaft is composed of only electric wires that do not include high rigidity wires. Therefore, when the drive shaft 140 is rotated, the drive shaft 140 can be preferably prevented from fluttering, and a tomographic image can be preferably acquired.

The rotation and movement operations of the drive shaft 140 are controlled by the control device 301. The connector portion 165 provided in the hub 160 is rotated while being connected to the external device 300, and the drive shaft 140 is rotated in conjunction with this. The rotation speed of the connector portion 165 and the drive shaft 140 is, for example, 1800 rpm.

Further, the signal transmission / reception unit 145 transmits ultrasonic waves and light into the body based on the signal transmitted from the control device 301. The signal corresponding to the reflected wave and the reflected light received by the signal transmitting / receiving unit 145 is sent to the control device 301 via the drive shaft 140 and the external device 300. The control device 301 generates a tomographic image of the body cavity based on the signal sent from the signal transmission / reception unit 145, and displays the generated image on the monitor 302.

As described above, the diagnostic imaging catheter 100 according to the present embodiment has a sheath 110 including a rotatable drive shaft 140 provided with a signal transmission / reception unit 145 at the tip thereof and a lumen 110a into which the drive shaft 140 is inserted so as to be movable back and forth. And have. Further, the drive shaft 140 includes a coil-shaped coil shaft 210 composed of three layers 220, 230, and 240, and the coil shaft 210 is more rigid than the electric wire 221a and the electric wire 221a connected to the ultrasonic transmission / reception unit 145a. Has a high rigidity wire 260. According to the diagnostic imaging catheter 100 configured in this way, since the electric wire 221a is included in the coil shaft 210, the drive shaft 140 is thinner than the configuration in which the electric wire is arranged in the internal space of the coil shaft. The diameter can be reduced. Further, since the coil shaft 210 has an electric wire 221a and a high rigidity wire 260, it is possible to suppress a decrease in the rigidity of the drive shaft 140. From the above, it is possible to reduce the diameter of the drive shaft 140 while suppressing the decrease in the rigidity of the drive shaft 140.

Further, the high-rigidity wire 260 has a first high-rigidity wire 221b, and the coil shaft 210 has a stranded wire 221 in which an electric wire 221a and a first high-rigidity wire 221b are twisted. According to the diagnostic imaging catheter 100 configured in this way, it is possible to suitably transmit an electric signal while suppressing a decrease in the rigidity of the drive shaft 140.

Further, the high-rigidity wire 260 has a second high-rigidity wire 222 having an outer diameter larger than that of the first high-rigidity wire 221b, and the coil shaft 210 is a stranded wire 221 in a cross-sectional view orthogonal to the axial direction of the coil shaft 210. The second high-rigidity wire 222 is arranged in parallel in the circumferential direction to form a coil. According to the diagnostic imaging catheter 100 configured in this way, the rigidity of the drive shaft 140 can be improved and the diameter of the drive shaft 140 can be reduced.

Further, the electric wire 221a includes one copper wire. According to the diagnostic imaging catheter 100 configured in this way, the attenuation of the electric signal received by the ultrasonic transmission / reception unit 145a can be suppressed and transmitted to the electrode terminal 165a.

Further, the coil shaft 210 is composed of three layers 220, 230 and 240, and the outermost layer 220 of the three layers 220, 230 and 240 includes an electric wire 221a. According to the diagnostic imaging catheter 100 configured in this way, the second high-rigidity wire 222 constituting the first layer 220 is wound around the second layer 230, and then the stranded wire 221 is wound around the second layer 230. Since the coil shaft 210 can be formed, the production becomes easy.

<Modification example 1>
Next, the configuration of the coil shaft 310 according to the first modification will be described with reference to FIGS. 10 and 11. FIG. 10 is a diagram corresponding to FIG. 5 of the coil shaft 310 according to the first modification. FIG. 11 is a diagram corresponding to FIG. 7 of the coil shaft 310 according to the first modification.

The coil shaft 310 according to the first modification differs from the coil shaft 210 according to the above-described embodiment in the configuration of the first layer 320. The same configuration as the diagnostic imaging catheter 100 according to the above embodiment is designated by the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 10, the coil shaft 310 is composed of three layers 320, 330, 340, and the three layers 320, 330, 340 are formed in a coil shape, respectively. The three layers 320, 330, and 340 are arranged so as to be the first layer 320, the second layer 330, and the third layer 340 in order from the outer side in the radial direction.

As shown in FIG. 10, the first layer 320 has a stranded wire 321 and a second high-rigidity wire 322. As shown in FIG. 10, the stranded wire 321 and the second high-rigidity wire 322 are arranged side by side in the circumferential direction in a cross-sectional view orthogonal to the axial direction. Further, as shown in FIG. 10, in a cross-sectional view orthogonal to the axial direction, two stranded wires 321 are provided along the circumferential direction, and six second high-rigidity wires 322 are provided along the circumferential direction. ing. The number of stranded wires 321 and the second high-rigidity wire 322 provided is not limited to the above.

As shown in FIG. 11, the stranded wire 321 is configured by twisting 13 electric wires 321a.

The second high-rigidity wire 322 has the same configuration as the second high-rigidity wire 222 according to the above-described embodiment. The second layer 330 has the same configuration as the second layer 230 according to the above-described embodiment. Further, the third layer 340 has the same configuration as the third layer 240 according to the above-described embodiment.

According to the coil shaft 310 according to the first modification configured as described above, the number of electric wires 321a can be increased as compared with the coil shaft 210 according to the above-described embodiment, so that the electric signal is preferably used. Can be transmitted.

<Modification 2>
Next, the configuration of the coil shaft 410 according to the second modification will be described with reference to FIGS. 12 and 13. FIG. 12 is a diagram corresponding to FIG. 5 of the coil shaft 410 according to the second modification. FIG. 13 is a diagram corresponding to FIG. 7 of the coil shaft 410 according to the second modification.

The coil shaft 410 according to the second modification is different from the coil shaft 210 according to the above-described embodiment in the configuration of the first layer 420. The same configuration as the diagnostic imaging catheter 100 according to the above embodiment is designated by the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 12, the coil shaft 410 is composed of three layers 420, 430, and 440, and the three layers 420, 430, and 440 are formed in a coil shape, respectively. The three layers 420, 430, and 440 are arranged so as to be the first layer 420, the second layer 430, and the third layer 440 in order from the outer side in the radial direction.

As shown in FIG. 12, the first layer 420 has an electric wire 421 and a second high-rigidity wire 422. As shown in FIG. 12, the electric wire 421 and the second high-rigidity wire 422 are arranged side by side in the circumferential direction in a cross-sectional view orthogonal to the axial direction. Further, as shown in FIG. 12, in a cross-sectional view orthogonal to the axial direction, two electric wires 421 are provided along the circumferential direction, and six second high-rigidity wires 422 are provided along the circumferential direction. ing. The number of electric wires 421 and the second high-rigidity wire 422 provided is not limited to the above.

As shown in FIG. 13, the electric wire 421 includes one copper wire.

The second high-rigidity wire 422 has the same configuration as the second high-rigidity wire 222 according to the above-described embodiment. The second layer 430 has the same configuration as the second layer 230 according to the above-described embodiment. Further, the third layer 440 has the same configuration as the third layer 240 according to the above-described embodiment.

As described above, the coil shaft 410 according to the second modification is formed in a coil shape in which the electric wire 421 and the second high-rigidity wire 422 are arranged in the circumferential direction in a cross-sectional view orthogonal to the axial direction. According to this configuration, the outer diameter of the electric wire 421 can be made larger than that of the coil shaft 210 according to the above-described embodiment, so that an electric signal can be suitably transmitted.

Although the diagnostic imaging catheter and the coil shaft according to the present invention have been described above through the embodiments and modifications, the present invention is not limited to the configurations described in the embodiments and modifications, and the scope of claims is described. It is possible to change as appropriate based on.

For example, in the embodiment described above, the two stranded wires 221 are both arranged in the outermost layer of the coil shaft 210, as shown in FIGS. 4-7. However, as shown in FIG. 14, the two stranded wires 521 may be arranged in different layers (for example, the upper side is the outermost layer and the lower side is the innermost layer).

Further, in the above-described embodiment, as shown in FIGS. 4 and 5, the three layers 220, 230, and 240 are coiled so that the number of turns is the same. However, as shown in FIG. 15, when the stranded wire 621 has an outer diameter larger than that of the second high-rigidity wire 222, the first layer 620 provided with the stranded wire 621 has a number of turns with respect to the second layer 630. May be configured in a coil shape so as to be different.

Further, in the above-described embodiment, as shown in FIG. 7, the electric wire 221a included in the stranded wire 221 includes one copper wire. However, as shown in FIG. 16, the electric wire 721a included in the stranded wire 721 may have a plurality of copper wires 721b twisted. According to this configuration, the flexibility of the electric wire 721a is improved as compared with the electric wire 221a according to the above-described embodiment, so that the flexibility of the coil shaft including the electric wire 721a can be improved.

Further, in the above-described embodiment, a mode in which the diagnostic imaging catheter according to the present invention is applied to a diagnostic imaging catheter having the functions of endovascular ultrasonic diagnosis (IVUS) and optical coherence tomography (OCT) will be described. bottom. However, the diagnostic imaging catheter according to the present invention is applied to, for example, an diagnostic imaging catheter having the functions of intravascular ultrasound diagnosis (IVUS) and optical frequency domain imaging (OFDI). May be good. In addition, the diagnostic imaging catheter according to the present invention can also be applied to a diagnostic imaging catheter used by the endovascular ultrasound diagnosis method (IVUS) alone.

100 diagnostic imaging catheter,
110 sheath,
110a lumens,
140 drive shaft,
145 signal transmitter / receiver,
145a ultrasonic transmitter / receiver,
145b Optical transmitter / receiver,
210, 310, 410 coil shaft,
220, 320, 420, 620 first layer,
221, 321, 521, 621, 721 stranded wire,
221a, 321a, 421, 721a electric wire,
221b 1st high rigidity wire,
222, 322, 422 second high-rigidity wire,
230, 330, 430, 630 second layer,
231 Second high-rigidity wire,
240, 340, 440 Third layer,
241 Second high-rigidity wire,
260 high-rigidity wire.

Claims (6)

A rotatable drive shaft with a signal transmitter / receiver at the tip,
The drive shaft has a sheath with a lumen into which the drive shaft is inserted so as to be movable back and forth.
The drive shaft comprises a coiled coil shaft composed of at least one layer.
The coil shaft, have a high rigidity line higher rigidity than the electrical line and the electrical line connected to the signal transmitting and receiving unit,
The high-rigidity wire has a first high-rigidity wire and has a first high-rigidity wire.
The coil shaft, wherein the electrical line and the first rigid line to have a the wire strands twisted, imaging catheter. The high-rigidity wire has a second high-rigidity wire having an outer diameter larger than that of the first high-rigidity wire.
The image diagnosis according to claim 1 , wherein the coil shaft is formed in a coil shape in which the stranded wire and the second high-rigidity wire are arranged in the circumferential direction in a cross-sectional view orthogonal to the axial direction of the coil shaft. Catheter for. The diagnostic imaging catheter according to claim 1 or 2 , wherein the electric wire includes one copper wire. The diagnostic imaging catheter according to claim 1 or 2 , wherein the electric wire is formed by twisting a plurality of copper wires. The coil shaft is composed of a plurality of layers.
The image diagnostic catheter according to any one of claims 1 to 4 , wherein the electric wire is included in the outermost layer of the plurality of layers. A rotatable drive shaft with a signal transmitter / receiver at the tip,
The drive shaft has a sheath with a lumen into which the drive shaft is inserted so as to be movable back and forth.
The drive shaft comprises a coiled coil shaft composed of at least one layer.
The coil shaft has an electric wire connected to the signal transmission / reception unit and a high-rigidity wire having a higher rigidity than the electric wire.
The coil shaft is a catheter for diagnostic imaging in which the electric wire and the high-rigidity wire are arranged in the circumferential direction in a cross-sectional view orthogonal to the axial direction of the coil shaft to form a coil.

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