JP7179943B2 - diagnostic imaging catheter - Google Patents

Description

The present invention relates to diagnostic imaging catheters.

In recent years, intravascular ultrasound (IVUS: Intra Vascular Ultra Sound) and optical coherence tomography (OCT: A dual-type diagnostic imaging catheter having both functions of optical coherence tomography has been developed (see Patent Document 1 below).

A dual-type diagnostic imaging catheter described in Patent Document 1 below includes a rotatable torque cable having an ultrasonic transmitter/receiver and an optical transmitter/receiver at its tip, and a sheath having a lumen into which the torque cable is rotatably inserted. and have When a tomographic image is obtained using a diagnostic imaging catheter, the sheath is inserted into a biological lumen, and the torque cable is retracted while being rotated within the sheath while the sheath is filled with a priming solution. A so-called pull-back operation (intermediate pull operation) for moving the drive shaft from the distal side to the proximal side and a pushing operation for pushing the drive shaft toward the distal side are performed. Simultaneously with this operation, the ultrasonic transmitting/receiving unit transmits ultrasonic waves toward the wall of the biological vessel and receives reflected waves reflected from the wall of the biological vessel. At the same time, the light transmitting/receiving unit also transmits light toward the wall of the biological vessel and receives reflected light reflected from the wall of the biological vessel.

JP 2015-164660 A

In the dual-type diagnostic imaging catheter disclosed in Patent Document 1, the light transmitting/receiving unit has a reflecting surface that reflects light propagated through the torque cable, and the light transmitting/receiving unit extends radially from the center of rotation. are placed at a distance from each other. When arranging both the ultrasonic transmission/reception unit and the optical transmission/reception unit in a limited space within the sheath, the optical transmission/reception unit has no choice but to be arranged at a position away from the center of rotation in the radial direction. sometimes not.

However, according to the study of the inventors, when a reflective coating capable of reflecting light is applied to the reflective surface, the more the optical transmitting/receiving unit is arranged in the radial direction from the center of rotation, the more priming occurs during rotation. The reflective coating applied to the reflective surface may peel off due to the liquid flow, making it impossible to obtain an accurate tomographic image.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a diagnostic imaging catheter capable of suppressing peeling off of a reflective coat of an optical transmitting/receiving section.

A diagnostic imaging catheter according to the present invention for achieving the above objects is a diagnostic imaging catheter for acquiring a tomographic image of a biological lumen, comprising a long sheath having a lumen; a rotatable elongated member disposed; a housing disposed at a distal end portion of the elongated member; and an optical transmitter/receiver and an ultrasonic transmitter/receiver held in the housing, wherein the optical transmitter/receiver a reflective surface coated with a reflective coating for reflecting light propagating in the axial direction of the elongated member ; It has an opening in which the circumference of the ultrasonic transmitting/receiving unit is larger than the circumference .

According to the diagnostic imaging catheter according to the present invention, the side wall portion covering the reflective surface can prevent the reflective coat from peeling off.

FIG. 4 is a diagram showing a state in which an external device is connected to the diagnostic imaging catheter according to the embodiment of the present invention; FIG. 4 is a side view of the catheter for diagnostic imaging according to the embodiment of the present invention before a pullback operation (intermediate pulling operation) is performed; FIG. 4 is a side view of the catheter for diagnostic imaging according to the embodiment of the present invention when a pullback operation is performed; 1 is a cross-sectional view showing a distal end portion of a diagnostic imaging catheter according to an embodiment of the present invention; FIG. 1 is a cross-sectional view showing a proximal end portion of a diagnostic imaging catheter according to an embodiment of the present invention; FIG. 1 is a perspective view showing details of a housing, an ultrasonic transmission/reception section, and an optical transmission/reception section of an imaging catheter according to an embodiment of the present invention; FIG. FIG. 6 is a top view of FIG. 5; FIG. 6 is a side view of FIG. 5; FIG. 8 is a cross-sectional view taken along line 8-8 of FIG. 7; 1 is a schematic diagram showing an example of use of a diagnostic imaging catheter according to an embodiment of the present invention; FIG. 1 is a schematic diagram showing an example of use of a diagnostic imaging catheter according to an embodiment of the present invention; FIG.

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

1 to 2B are diagrams for explaining the overall configuration of a diagnostic imaging catheter 100 according to an embodiment of the present invention. 3 to 8 are diagrams for explaining each part of the diagnostic imaging catheter 100. FIG. 9A and 9B are cross-sectional views schematically showing a usage example of the diagnostic imaging catheter 100. FIG.

The diagnostic imaging catheter 100 is a dual-type diagnostic imaging catheter having both intravascular ultrasound (IVUS) and optical coherence tomography (OCT) functions. The dual-type diagnostic imaging catheter 100 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 a tomographic image by both IVUS and OCT. It exists and can be used by switching between these modes. As shown in FIG. 1, the diagnostic imaging catheter 100 is driven by being connected to an external device 300 .

A diagnostic imaging catheter 100 will be described with reference to FIGS. 1 to 4. FIG.

As shown in FIGS. 1, 2A and 2B, the diagnostic imaging catheter 100 generally includes a sheath 110 inserted into a body cavity of a living body, an outer tube 120 provided on the proximal side of the sheath 110, An inner shaft 130 inserted into the outer tube 120 so as to move back and forth, and a drive shaft 140 (an “long member”) rotatably provided in the sheath 110 having a signal transmitting/receiving unit 145 for transmitting/receiving signals at its tip. equivalent), a unit connector 150 provided on the proximal side of the outer tube 120 and configured to receive the inner shaft 130, and a hub 160 provided on the proximal side of the inner shaft 130. .

In the description of the specification, the side of the diagnostic imaging catheter 100 inserted into the body cavity is referred to as the distal side, and the side of the hub 160 provided on the diagnostic imaging catheter 100 is referred to as the proximal side. Also, the extending direction of the sheath 110 is referred to as an axial direction. In addition, in the diagnostic imaging catheter 100 and each component, a portion including a certain range in the axial direction from the distal end (most distal end) is defined as the distal end portion, and a certain range in the axial direction from the proximal end (most proximal end) is defined as the distal end portion. The portion that includes is defined as the proximal portion.

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

The hub 160, the inner shaft 130, the drive shaft 140, and the signal transmitting/receiving section 145 are connected to each other so as to integrally move back and forth in the axial direction. Therefore, for example, when the hub 160 is pushed toward the distal end side, the inner shaft 130 connected to the hub 160 is pushed into the outer tube 120 and the unit connector 150, and the drive shaft 140 and signal transmission/reception are pushed. Portion 145 moves distally inside sheath 110 . For example, when hub 160 is pulled proximally, inner shaft 130 is pulled out from outer tube 120 and unit connector 150 as indicated by arrow a1 in FIGS. The signal transmitter/receiver 145 moves inside the sheath 110 to the proximal side as indicated by an arrow a2.

As shown in FIG. 2A, when the inner shaft 130 is pushed all the way to the tip side, the tip of the inner shaft 130 reaches near the relay connector 170 . At this time, the signal transmitter/receiver 145 is positioned near the distal end 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, the tip of the inner shaft 130 is provided with a connector 131 for preventing detachment. The pull-out prevention connector 131 has a function of preventing the inner shaft 130 from slipping out of the outer tube 120 . The disconnection-preventing connector 131 is positioned at a predetermined position on the inner wall of the unit connector 150 when the hub 160 is pulled most proximally, that is, when the inner shaft 130 is most pulled out from the outer tube 120 and the unit connector 150. configured to hook onto the

As shown in FIG. 3, the drive shaft 140 has a flexible tubular body 141 in which an electric signal cable 142 and an optical fiber 143 connected to a signal transmitter/receiver 145 are arranged. The tubular body 141 can be composed of, for example, multilayer coils with different winding directions around the axis. Examples of coil constituent materials include stainless steel and Ni--Ti (nickel-titanium) alloys. In this embodiment, the electric signal cable 142 includes two signal lines 142a and 142b (see FIG. 5) electrically connected to electrode terminals 165a (see FIG. 4) provided in a connector section 165, which will be described later; It has

The signal transmission/reception unit 145 has an ultrasonic transmission/reception unit 145a that transmits/receives ultrasonic waves and an optical transmission/reception unit 145b that transmits/receives light.

The ultrasonic transmission/reception unit 145a has a transducer, and has a function of transmitting ultrasonic waves based on a pulse signal into the body cavity and receiving ultrasonic waves reflected from living tissue in the body cavity. The ultrasonic transmission/reception unit 145a is electrically connected to the electrode terminal 165a (see FIG. 4) via the electric signal cable 142. As shown in FIG.

A piezoelectric material such as ceramics or crystal can be used as the transducer included in the ultrasonic transmission/reception unit 145a, for example.

The optical transmitter/receiver 145b continuously transmits the transmitted light into the body cavity and continuously receives the light reflected by the living tissue in the body cavity. The optical transmitter/receiver 145b is provided at the tip of the optical fiber 143 and has an optical element that has a lens function for condensing light and a reflection function for reflecting light.

In this embodiment, as shown in FIG. 7, the optical element included in the light transmitting/receiving section 145b is configured by a ball lens including a flat surface 145c and a spherical surface 145d. The plane 145 c is provided with a reflective coating that reflects the light propagating from the optical fiber 143 . The constituent material of the reflective coat is not particularly limited as long as it can reflect light, and examples thereof include aluminum. Light propagating from optical fiber 143 is reflected at plane 145c, condensed at spherical surface 145d, and transmitted into the body cavity. The light reflected by the living tissue in the body cavity is condensed on the spherical surface 145 d, reflected on the flat surface 145 c and propagated to the optical fiber 143 . The configuration of the optical transmitter/receiver 145b is not particularly limited as long as it has a reflective surface with a reflective coating that reflects the light propagating from the optical fiber 143. FIG. For example, the light transmitting/receiving section 145b may be configured by a plate member to which a reflective coating is applied.

The signal transmitter/receiver 145 is housed inside a housing 146, as shown in FIG. The proximal end of housing 146 is connected to drive shaft 140 . The housing 146 has a shape in which an opening 146a is provided on the cylindrical surface of a cylindrical metal pipe so as not to hinder the progress of ultrasonic waves transmitted and received by the ultrasonic transmission/reception section 145a and light transmitted and received by the optical transmission/reception section 145b. there is The housing 146 can be formed by, for example, laser processing. It should be noted that the housing 146 may be formed by cutting a metal block or by MIM (metal powder injection molding).

A tip member 147 is provided at the tip of the housing 146 . The tip member 147 has a substantially hemispherical outer shape. By forming the distal end member 147 in a hemispherical shape, it is possible to suppress friction and catching with the inner surface of the sheath 110 . In addition, the tip member 147 may be configured by a coil, for example. Further, the distal end member 147 may not be provided at the distal end of the housing 146 .

The sheath 110 has a lumen 110a into which the drive shaft 140 is inserted so as to move back and forth. Attached to the distal end of the sheath 110 is a guide wire insertion member 114 that is arranged side by side with a lumen 110 a provided in the sheath 110 and has a guide wire lumen 114 a through which a second guide wire W described later can be inserted. The sheath 110 and the guide wire insertion member 114 can be integrally configured by heat sealing or the like. The guidewire insertion member 114 is provided with a marker 115 having X-ray contrastability. The marker 115 is composed of a metal pipe such as Pt, Au, or the like, which is highly opaque to X-rays. For the purpose of improving the mechanical strength, an alloy in which Ir is mixed with the above Pt may be used. Furthermore, the marker 115 may be composed of a metal coil instead of a metal pipe.

A communicating hole 116 is formed at the distal end of the sheath 110 to communicate the inside and the outside of the lumen 110a. A reinforcing member 117 is provided at the distal end of the sheath 110 to firmly join and support the guide wire insertion member 114 . The reinforcing member 117 is formed with a communicating passage 117 a that communicates the communicating hole 116 with the interior of the lumen 110 a arranged on the proximal side of the reinforcing member 117 . Note that the reinforcing member 117 may not be provided at the distal end of the sheath 110 .

The communication hole 116 is a priming liquid discharge hole for discharging the priming liquid. When using the diagnostic imaging catheter 100, a priming process is performed to fill the sheath 110 with a priming liquid. For example, when ultrasonic waves are transmitted without filling the sheath 110 with the priming liquid, the acoustic impedance difference between the matching layer arranged on the surface of the transducer of the ultrasonic transmission/reception unit 145a and the air is large. Therefore, there is a possibility that the ultrasonic wave will be reflected at the interface between the matching layer and the air, and the ultrasonic wave will not be able to reach the wall of the living canal. On the other hand, by filling the sheath 110 with a priming liquid whose acoustic impedance value is close to that of the matching layer, ultrasonic waves can penetrate deep into the wall of the living body. When the priming process is performed, the priming liquid can be discharged to the outside from the communication hole 116 to discharge gas such as air from the inside of the sheath 110 together with the priming liquid.

The distal end portion of the sheath 110, which is the range in which the signal transmitting/receiving portion 145 moves in the axial direction of the sheath 110, constitutes a window portion formed with higher permeability for inspection waves such as light and ultrasonic waves than other portions. .

The sheath 110, the guide wire insertion member 114, and the reinforcing member 117 are preferably made of flexible materials, but the materials are not particularly limited, and examples thereof 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. 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. 4, the hub 160 includes a hub body 161 having a hollow shape, a connector case 165c 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 (orientation) of the hub 160 when connecting to the hub 300, a connection pipe 164b for holding the drive shaft 140, a bearing 164c for rotatably supporting the connection pipe 164b, A connector section in which a sealing member 164a for preventing the priming liquid from leaking from between the connection pipe 164b and the bearing 164c toward the proximal side, an electrode terminal 165a connected to the external device 300, and an optical connector 165b are arranged inside. 165 and .

An inner shaft 130 is connected to the tip of the hub body 161 . Drive shaft 140 is pulled out from inner shaft 130 inside hub body 161 .

An injection device S (see FIG. 1) for injecting a priming solution is connected to the port 162 when performing the priming process.

The connection pipe 164b holds the driving shaft 140 in order to transmit the rotation of the electrode terminal 165a and the optical connector 165b rotated by the external device 300 to the driving shaft 140. FIG. An electrical signal cable 142 and an optical fiber 143 (see FIG. 3) are passed through the interior of the connection pipe 164b.

The connector section 165 includes an electrode terminal 165a electrically connected to the electric signal cable 142, and an optical connector 165b connected to an optical fiber. A signal received by 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. A signal received by the optical transmitter/receiver 145b is transmitted to the external device 300 via the optical connector 165b, subjected to predetermined processing, and displayed as an image.

Referring 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 .

The external device 300 also has a motor 300a as a power source for rotating the drive shaft 140 and a motor 300b as a power source for moving the drive shaft 140 in the axial direction. The rotary motion of the motor 300b is converted into axial motion by a linear motion converting mechanism 300c connected to the motor 300b. For example, a ball screw, a rack and pinion mechanism, or the like can be used as the linear motion converting mechanism 300c.

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

Next, the housing 146, the ultrasonic transmission/reception section 145a, the optical transmission/reception section 145b, etc. will be described in detail with reference to FIGS. In the following description, the side of the housing 146 where the opening 146a is provided (upper side in FIG. 7) is referred to as the upper side. Also, the rotation axis of the drive shaft 140 is referred to as a rotation axis Y. As shown in FIG. A direction orthogonal to the rotation axis Y is called a radial direction.

The ultrasonic transmitter/receiver 145a is attached to the backing member 210 as shown in FIGS. The backing member 210 scatters and attenuates ultrasonic waves traveling from the ultrasonic transmission/reception section 145 a toward the opposite direction of the opening 146 a of the housing 146 . Backing member 210 is attached to rim 146b surrounding opening 146a of housing 146 . Although the method of fixing the backing member 210 to the housing 146 is not particularly limited, for example, it can be fixed by bonding with an adhesive. In this embodiment, the backing member 210 is arranged in the housing so that the ultrasonic wave transmitting/receiving section 145a transmits the ultrasonic wave SW in a direction inclined toward the base end side with respect to the radiation direction of the drive shaft 140, as shown in FIG. 146.

The optical transmitter/receiver 145b is fixed to the housing 146 via a positioning member 220, as shown in FIG.

In this embodiment, as shown in FIG. 7, the positioning member 220 is positioned at the optical transmitter/receiver 145b so that the ultrasonic wave SW transmitted from the ultrasonic transmitter/receiver 145a and the light ML transmitted from the optical transmitter/receiver 145b intersect. position is fixed.

As shown in FIGS. 7 and 8, the positioning member 220 has a substantially cylindrical outer shape.

Approximately at the center of the positioning member 220, as shown in FIG. 8, an insertion hole 221 through which the electric signal cable 142 and the optical fiber 143 can be inserted is provided. The insertion hole 221 includes a first insertion portion 221a formed by hollowing out the positioning member 220 in a substantially semi-cylindrical shape, and a second insertion portion 221b connected to the first insertion portion 221a and into which the optical fiber 143 can be fitted. In order to protect the connecting portion between the optical fiber 143 and the optical transmitting/receiving section 145b, the connecting portion may be covered with a protective cover 144. FIG.

Since the signal transmitting/receiving section 145, the electric signal cable 142, the optical fiber 143, the positioning member 220, etc. are arranged in the housing 146, the inner diameter r2 (see FIG. 8A) of the housing 146 is preferably large. On the other hand, the outer diameter of the housing 146 is preferably large enough to maintain the slidability of the sheath 110 in the biological lumen. . Therefore, there is a limit to increasing the inner diameter r2 of the housing 146. FIG. Therefore, there is a limit to increasing the outer diameter of the positioning member 220 accommodated in the housing 146 .

If the optical fiber 143 covered with the protective cover 144 is arranged so that the axial center of the optical fiber 143 is positioned on the rotation axis Y of the drive shaft 140, the outer diameter r1 of the optical fiber 143 including the protective cover 144 is As a result, it becomes difficult to secure a space (first insertion portion 221a) for arranging the electrical signal cable 142 (two signal lines 142a and 142b) having a constant outer diameter r3. Therefore, the second insertion portion 221b is provided in the positioning member 220 so that the center position of the optical fiber 143 arranged in the second insertion portion 221b is separated from the center position (rotational axis Y) of the drive shaft 140. . Thereby, a space (first insertion portion 221a) for arranging the electric signal cable 142 can be secured. Therefore, the center position of the optical transmitter/receiver 145b is arranged at a position away from the center position (rotational axis Y) of the drive shaft 140 on the cross section perpendicular to the rotational axis Y of the drive shaft 140 .

A recess 222 is provided on the outer peripheral surface of the positioning member 220 as shown in FIG. The recesses 222 are used to adjust the position of the positioning member 220 in the circumferential direction during the manufacturing stage, although the details will be described later.

Although the positioning member 220 is not particularly limited, it preferably contains a material (radio-opaque material) such as Pt, Au, Pt--Ir alloy or the like under X-ray fluoroscopy. By configuring the positioning member 220 with such a material, the operator can easily grasp the position of the light transmitting/receiving section 145b under X-ray fluoroscopy.

As shown in FIG. 7, the positioning member 220 is fixed to the inner surface of the housing 146 so that the flat surface 145c of the optical transmitter/receiver 145b is arranged radially inward of the spherical surface 145d.

As shown in FIG. 7, the housing 146 has side walls 146d arranged to cover at least the plane 145c of the optical transmitter/receiver 145b. As shown in FIG. 5, two side wall portions 146d are provided so as to sandwich the optical transmitting/receiving portion 145b in the circumferential direction. The side wall portion 146d is integrally formed with the housing 146 in this embodiment. However, the side wall portion 146d may be configured separately from the housing 146 and joined to the housing 146 with an adhesive or the like.

As shown in FIGS. 6 and 7, the side wall portion 146d is configured to expose the spherical surface 145d (light transmitting/receiving surface) of the light transmitting/receiving portion 145b while covering the flat surface 145c. Therefore, it is possible to prevent the side wall portion 146d from obstructing the path (optical path) of light transmitted and received by the optical transmitter/receiver 145b.

As shown in FIG. 6, the housing 146 is provided with a notch 146c penetrating through the portion accommodating the positioning member 220 in the thickness direction. As shown in FIG. 8, the recess 222 provided in the positioning member 220 and the notch 146c provided in the housing 146 are provided in radially overlapping positions. Therefore, for example, when manufacturing the diagnostic imaging catheter 100, a jig such as a needle or tweezers is inserted from the notch 146c and hooked on the recess 222, the positioning member 220 is rotated with respect to the housing 146, and the ultrasonic wave SW and the light beam are rotated. The circumferential position of the positioning member 220 relative to the housing 146 can be fine tuned such that the MLs intersect, and then the positioning member 220 can be secured relative to the housing 146 . Although the method of fixing the positioning member 220 to the housing 146 is not particularly limited, it can be adhered with an adhesive, for example. In this case, for example, the positioning member 220 may be fixed to the housing 146 by rotating the positioning member 220 while injecting the adhesive from the notch 146c so that the adhesive spreads over the peripheral surface of the positioning member 220. can be done.

9A and 9B are diagrams for explaining a usage example of the diagnostic imaging catheter 100 according to the embodiment. An example of use when the diagnostic imaging catheter 100 is inserted into a blood vessel 900 (organ lumen) will be described below.

First, the user connects the injection device S for injecting the priming liquid to the port 162 while pulling the hub 160 to the most proximal side (see FIG. 2B), and injects the priming liquid into the lumen 110a of the sheath 110. inject.

When the priming liquid is injected into the lumen 110a, the priming liquid is released to the outside of the sheath 110 through the communication path 117a and the communication hole 116 shown in FIG. It can be discharged to the outside (priming process).

After the priming process, the user connects the external device 300 to the connector section 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 proximal end of the unit connector 150 (see FIG. 2A), and moves the signal transmitting/receiving section 145 to the distal side.

Next, the user uses an introducer kit (not shown) to create a port on the wrist or thigh for introducing the diagnostic imaging catheter 100 into the body lumen. Next, a first guide wire (not shown) is inserted through the port to near the coronary ostia of the heart. Next, the guiding catheter 800 is introduced to the ostium of the coronary artery along the first guidewire. Next, the first guide wire is withdrawn, and the second guide wire W is inserted through the guiding catheter 800 to the lesion site. Next, the diagnostic imaging catheter 100 is inserted along the second guide wire W to the lesion.

Next, as shown in FIG. 9A, the diagnostic imaging catheter 100 is advanced along the lumen 800a to protrude from the tip opening of the guiding catheter 800. As shown in FIG. After that, while inserting the second guide wire W through the guide wire lumen 114a, the diagnostic imaging catheter 100 is further pushed along the second guide wire W and inserted into the blood vessel 900 at the target position. As the guiding catheter 800, a known guiding catheter having a port (not shown) to which a syringe (not shown) can be connected can be used.

Next, the blood in the blood vessel 900 is temporarily replaced with flush liquid such as a contrast medium. A syringe containing flushing fluid is connected to the port of the guiding catheter 800 in the same manner as in the priming process described above, and the plunger of the syringe is pushed to inject the flushing fluid into the lumen 800a of the guiding catheter 800. FIG. The flush liquid passes through the lumen 800a of the guiding catheter 800 and is introduced into the blood vessel 900 through its tip opening, as indicated by arrow C in FIG. 9B. The introduced flushing liquid pushes the blood around the distal end of the sheath 110 away, and the surroundings of the distal end of the sheath 110 are filled with the flushing liquid.

When obtaining a tomographic image at a target position in the blood vessel 900, the signal transmitter/receiver 145 rotates together with the drive shaft 140 and moves to the proximal side (pullback operation). Simultaneously with the pullback operation, the ultrasonic transmission/reception unit 145a transmits ultrasonic waves SW toward the blood vessel wall 900b and receives ultrasonic waves reflected from the blood vessel wall 900b. At the same time, the light transmitting/receiving unit 145b also transmits the light ML toward the blood vessel wall 900b and receives the light reflected by the blood vessel wall 900b.

At this time, the inside of the sheath 110 is filled with the priming liquid. According to studies by the present inventors, when the flat surface 145c of the optical transmitter/receiver 145b is exposed, the farther the optical transmitter/receiver 145b is located from the rotation axis Y of the drive shaft 140 in the radial direction, the more the rotation. Sometimes, the reflective coating applied to the flat surface 145c tends to peel off due to the flow of the priming liquid. This is because the optical transmitter/receiver 145b is arranged at a position farther in the radial direction from the rotation axis Y of the drive shaft 140, the faster the optical transmitter/receiver 145b rotates, and the greater the resistance received from the priming liquid. it is conceivable that. According to the diagnostic imaging catheter 100 according to the present embodiment, since the side wall portion 146d covers the flat surface 145c on which the reflective coating is applied, it is possible to suppress the peeling off of the reflective coating from the flat surface 145c due to the priming liquid during rotation.

The rotation and movement of drive shaft 140 are controlled by control device 301 . The connector portion 165 provided inside the hub 160 is rotated while being connected to the external device 300, and the drive shaft 140 is rotated accordingly. Further, based on a signal sent from the control device 301, the signal transmitter/receiver 145 transmits ultrasonic waves and light into the body. A signal corresponding to the reflected wave and the reflected light received by the signal transmitter/receiver 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 transmitter/receiver 145 and displays the generated image on the monitor 302 .

As described above, the diagnostic imaging catheter 100 according to the present embodiment is a diagnostic imaging catheter for obtaining a tomographic image of a biological lumen. The diagnostic imaging catheter 100 includes an elongated sheath 110 having a lumen 110a, a rotatable drive shaft 140 disposed in the lumen 110a of the sheath 110, a housing 146 disposed at the distal end of the drive shaft 140, An optical transmitter/receiver 145b and an ultrasonic transmitter/receiver 145a held in a housing 146 are provided. The light transmitting/receiving section 145b has a reflecting surface (flat surface 145c) with a reflecting coating that reflects light along the axial direction of the drive shaft. The center position of the optical transmitter/receiver 145b is located away from the center position of the drive shaft 140 on the cross section perpendicular to the axial direction of the drive shaft 140 . The housing 146 has a side wall portion 146d arranged to cover at least the reflecting surface (flat surface 145c) of the optical transmitting/receiving portion 145b.

According to the diagnostic imaging catheter 100, the side wall 146d covering the reflective surface (flat surface 145c) can prevent the reflective coat from peeling off due to the flow of the priming liquid filled in the sheath 110 during rotation. Therefore, even when the center position of the optical transmitter/receiver 145b is located away from the center position of the drive shaft 140 on the cross section perpendicular to the axial direction of the drive shaft 140, an accurate tomographic image can be acquired.

The optical transmitter/receiver 145b includes a spherical surface 145d and a flat surface 145c arranged radially inward of the spherical surface 145d. A reflective coating is applied to the flat surface 145c. , to expose the spherical surface 145d. Therefore, by covering the flat surface 145c, which is the reflective surface, with the side wall portion 146d, peeling of the reflective coat is suppressed, and at the same time, the spherical surface, which is the light exit surface, is exposed to prevent the side wall portion 146d from hindering the propagation of light. can.

Moreover, the side wall portion 146 d is formed integrally with the housing 146 . Therefore, the number of components of the diagnostic imaging catheter 100 can be reduced compared to the case where the side wall portion 146d is configured separately from the housing 146. FIG.

Although the diagnostic imaging catheter according to the present invention has been described above through the embodiments, the present invention is not limited to the configurations described in the embodiments and modifications, and can be appropriately modified based on the description of the claims. It is possible to

For example, in the above-described embodiments, the imaging catheter according to the present invention is applied to an imaging catheter having intravascular ultrasound (IVUS) and optical coherence tomography (OCT) functions. . However, the diagnostic imaging catheter according to the present invention is not particularly limited as long as it is a diagnostic imaging catheter that uses ultrasound and light as examination waves. It may be applied to a diagnostic imaging catheter having the function of OFDI (Optical Frequency Domain Imaging).

Further, for example, in the above-described embodiments, the form in which the ultrasonic wave transmitted from the ultrasonic transmission/reception section and the light transmitted from the optical transmission/reception section intersect has been described. However, for example, the transmission direction of ultrasonic waves transmitted from the ultrasonic transmission/reception section and the transmission direction of light transmitted from the optical transmission/reception section may be parallel. If the ultrasound and light are parallel, they are separated by a constant distance along the axial direction of the drive shaft. For this reason, for example, when a plurality of tomographic images are acquired using ultrasonic waves and light as inspection waves along with a pullback operation, taking into consideration that the ultrasonic waves and light are separated by a certain distance, It is possible to extract a tomographic image acquired at the same position in the body lumen using ultrasound as an inspection wave and a tomographic image acquired using light as an inspection wave.

For example, in the above-described embodiment, the electric signal cable (signal line) has been described as being composed of two cables. However, the electrical signal cable may be configured by, for example, a coaxial cable (one cable). Also, the electrical signal cable may be a twisted pair cable in which two cables are wound around an optical fiber.

100 diagnostic imaging catheter,
110 sheath,
110a lumens;
140 drive shaft (long member),
145a ultrasonic transmission/reception unit,
145b optical transceiver,
145c the plane of the optical transceiver,
145d Spherical surface of optical transceiver,
146 housing,
146d side wall,
Y axis of rotation of the shaft member.

Claims (5)

A diagnostic imaging catheter for acquiring a tomographic image of a biological lumen,
an elongated sheath having a lumen;
a rotatable elongated member disposed in the lumen of the sheath;
a housing disposed at the distal end of the elongated member;
an optical transceiver and an ultrasonic transceiver held in the housing;
The light transmitting/receiving unit includes a reflecting surface coated with a reflective coating that reflects light propagating in the axial direction of the elongated member ,
The catheter for diagnostic imaging, wherein the housing has an opening that is larger around the ultrasonic transmitter/receiver than around the optical transmitter/receiver on a cross section perpendicular to the axial direction of the elongated member . 2. The diagnostic imaging catheter according to claim 1 , wherein said housing has two side wall portions arranged so as to sandwich at least said reflecting surface of said light transmitting/receiving portion therebetween . the optical transceiver includes a spherical surface and a flat surface disposed radially inward of the spherical surface;
The reflective coat is applied to the plane,
3. The diagnostic imaging catheter of claim 2, wherein the two side walls sandwich the flat surface and expose the spherical surface . 4. The diagnostic imaging catheter according to claim 3, wherein the plane is located away from the central position of the elongated member on a cross section perpendicular to the axial direction of the elongated member. The diagnostic imaging catheter according to any one of claims 2 to 4, wherein the two side walls are integrally formed with the housing.

Images