JP2017093506A - Imaging diagnosis catheter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an imaging diagnosis catheter which has improved performance for delivery to a lesioned part and which can be disposed in the lesioned part without expanding the lesioned part.SOLUTION: An imaging diagnosis catheter 100 includes: a sheath 110 having a tip opening part 111 which is inserted into a living body lumen; a drive shaft 140 provided so as to rotate, and move forward and backward in an axial direction of the sheath within the sheath, an imaging core 150 which has an ultrasonic vibrator 151 capable of transmitting/receiving an ultrasonic wave and a housing 152 holding the ultrasonic vibrator and which is provided at the tip of drive shaft, and a tip member 160 which has a coil 161 for guiding the movement of the sheath in the living body lumen and which is provided at the tip of the imaging core. The tip of the coil can be protruded from the tip opening part of the sheath in accordance with the movement of the drive shaft to a tip side.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a diagnostic imaging catheter.

  2. Description of the Related Art Conventionally, in order to diagnose a lesion or the like formed in a living body lumen, an imaging diagnostic catheter that acquires an image of a living body lumen using an inspection wave such as an ultrasonic wave or light has been used.

  The diagnostic imaging catheter has a long sheath inserted into a living body lumen, a drive shaft that is rotatable and axially movable in a sheath lumen (working lumen), and a distal end portion of the drive shaft And a transmission / reception unit for transmitting / receiving an inspection wave. Then, the transmitter / receiver transmits and receives the examination wave while acquiring the image of the living body lumen while rotating backwardly toward the proximal end while rotating the drive shaft within the shaft.

  In general, a diagnostic imaging catheter is delivered to a lesion along a guide wire inserted into a living body lumen so that the living body lumen that is meandering or curved can be moved. For this reason, for example, in addition to a working lumen in which a drive shaft or the like moves forward and backward, a guide wire lumen for inserting a guide wire may be provided at the distal end portion of the sheath (see Patent Document 1 below).

JP2015-119994A

  Since the diagnostic imaging catheter described in Patent Document 1 includes two lumens of a working lumen and a guide wire lumen, the outer diameter of the distal end portion is relatively large, and the flexibility of the distal end portion is also relatively large. Lower. For example, when acquiring a diagnostic image of a lesion with advanced stenosis, an insertion path is secured in advance in the lesion using a penetration catheter, the penetration catheter is removed from the living body, and the insertion path is then removed. In some cases, a procedure for causing the diagnostic imaging catheter to enter the stenosis portion may be performed, but the diagnostic imaging catheter formed with low flexibility at the distal end may not be smoothly delivered to the lesion. . In addition, even if delivery to the periphery of the lesion is possible, if the outer diameter of the diagnostic imaging catheter is larger than the outer diameter of the penetrating catheter, the diagnostic imaging catheter cannot be inserted into the lesion. Even if this occurs, there may be a problem that the lesion is unintentionally spread unintentionally.

  The present invention has been made in view of the above-described problems, and provides a diagnostic imaging catheter that is further improved in deliverability to a lesion and can be placed in the lesion without expanding the lesion. For the purpose.

  A diagnostic imaging catheter that achieves the above object includes a distal end opening, a sheath inserted into a living body lumen, and a drive shaft provided in the sheath so as to be rotatable and movable back and forth in the axial direction of the sheath. A transmission / reception unit capable of transmitting / receiving a test wave and a housing holding the transmission / reception unit, an imaging core provided at a distal end portion of the drive shaft, and a coil for guiding the movement of the sheath in the living body lumen, And a tip member provided at the tip of the imaging core. The distal end portion of the coil can project from the distal end opening portion of the sheath as the drive shaft moves toward the distal end side.

  According to the diagnostic imaging catheter configured as described above, the coil protruding from the distal end opening of the sheath functions to guide the movement of the sheath in the living body lumen. There is no need to deliver to the lesion. For this reason, it is not necessary to provide a guide wire lumen at the distal end portion of the sheath, and the outer diameter of the distal end portion of the sheath can be made relatively small and flexibility can be increased. As a result, for example, the diagnostic imaging catheter can be inserted into the lumen of another medical device such as a penetrating catheter or a balloon catheter previously inserted into the lesioned portion and can be smoothly moved. For this reason, it becomes possible to deliver the diagnostic imaging catheter to the lesion more reliably and arrange it in the lesion without expanding the lesion.

It is a top view which shows schematically the external apparatus connected to the catheter for image diagnosis which concerns on embodiment, and the catheter for image diagnosis. FIG. 2A is a plan view schematically showing an entire configuration of a diagnostic imaging catheter according to the embodiment, FIG. 2A is a diagram showing a state before the pullback operation is performed, and FIG. 2B is a diagram showing the pullback operation. It is a figure which shows the state at the time of implementing. FIGS. 3A and 3B are diagrams showing the configuration of each part of the diagnostic imaging catheter according to the embodiment, FIG. 3A is an enlarged cross-sectional view showing the configuration of the distal end side of the diagnostic imaging catheter, and FIG. It is an expanded sectional view showing composition on the base end side of a catheter. It is an expanded sectional view showing roughly the tip member of the diagnostic imaging catheter concerning an embodiment. It is a perspective view showing roughly a holding part of a diagnostic imaging catheter concerning an embodiment. FIG. 6A is a diagram schematically illustrating a first usage example of the diagnostic imaging catheter according to the embodiment, and FIG. 6A is a diagram illustrating a state where the penetrating catheter is inserted into a lesioned portion, and FIG. FIG. 6 is a diagram showing a state in which an imaging diagnostic catheter is inserted and moved into the lumen of the penetrating catheter, and FIG. 6C is a diagram showing a state in which an imaging core is arranged at the image acquisition start position. FIG. 6D is a diagram illustrating a state in which an image is acquired while performing a pullback operation. 7A and 7B are diagrams schematically illustrating a second usage example of the diagnostic imaging catheter according to the embodiment, in which FIG. 7A is a diagram illustrating a state in which a balloon catheter is inserted into a lesioned portion, and FIG. FIG. 7C is a diagram showing a state in which an image diagnostic catheter is inserted and moved into the lumen of the balloon catheter, FIG. 7C is a diagram showing a state in which an imaging core is disposed at the image acquisition start position, and FIG. FIG. 4D is a diagram illustrating a state in which an image is acquired while performing a pullback operation.

  Hereinafter, the diagnostic imaging catheter 100 according to the present embodiment will be described with reference to the accompanying drawings. In addition, the following description does not limit the meaning of the technical scope and terms described in the claims. In addition, the dimensional ratios in the drawings are exaggerated for convenience of explanation, and may differ from actual ratios.

  FIG. 1 is a diagram schematically showing a diagnostic imaging catheter 100 and an external device 200 connected to the diagnostic imaging catheter 100 according to the present embodiment, and FIG. 2 is a schematic diagram showing the overall configuration of the diagnostic imaging catheter 100. FIGS. 3 to 5 are diagrams showing the configuration of each part of the diagnostic imaging catheter 100, and FIGS. 6 and 7 are diagrams for explaining an example of use of the diagnostic imaging catheter 100. FIG. is there. 5 shows a state in which the tip member 160 or the like does not protrude from the holding portion 113 in order to facilitate the description of the holding portion 113, but in this embodiment, as shown in FIG. In addition, at least the tip of the coil 161 is configured to protrude from the holding portion 113 from the holding portion 113.

  The diagnostic imaging catheter 100 according to the present embodiment is configured as a diagnostic imaging catheter that is used for intravascular ultrasound diagnosis (IVUS: Intra Vascular Ultra Sound).

  As shown in FIG. 1, the diagnostic imaging catheter 100 generally includes a sheath 110 inserted into a living body lumen, an outer tube 120 provided on the proximal end side of the sheath 110, and an axial direction in the outer tube 120. An inner shaft 130 that is inserted into the sheath 110 so as to be movable back and forth, a drive shaft 140 that is rotatably and axially movable in the sheath 110, an imaging core 150 that is provided at the tip of the drive shaft 140, and an imaging core 150 A distal end member 160 provided at the distal end of the outer tube 120, a unit connector 170 provided on the proximal end side of the outer tube 120 and configured to receive the inner shaft 130, and a hub 180 provided on the proximal end side of the inner shaft 130. And a relay connector 190 for connecting the sheath 110 and the outer tube 120.

  In the description of the specification, the extending direction of the sheath 110 is referred to as an axial direction, the side inserted into the living body lumen in the axial direction is referred to as the distal end side, and the proximal side where the hub 180 is provided is referred to as the axial direction. This is called the proximal side. In addition, the distal end portion means a certain range including the distal end (the most distal end) and the periphery thereof, and the proximal end portion means a certain range including the proximal end (the most proximal end) and the periphery thereof.

  As shown in FIG. 2A, the drive shaft 140 passes through the sheath 110, the outer tube 120 connected to the proximal end of the sheath 110, and the inner shaft 130 inserted into the outer tube 120. As shown, it extends to the inside of the hub 180.

  The hub 180, the inner shaft 130, the drive shaft 140, the imaging core 150, and the tip member 160 are connected to each other so as to integrally move forward and backward in the axial direction. Therefore, for example, when the hub 180 is pushed toward the distal end side, the inner shaft 130 is pushed into the outer tube 120 and the unit connector 170 as shown in FIG. The shaft 140, the imaging core 150, and the tip member 160 move to the tip side. For example, when the hub 180 is pulled to the proximal end side, the inner shaft 130 is pulled out from the outer tube 120 and the unit connector 170 as indicated by an arrow a1 in FIG. 140, the imaging core 150, and the distal end member 160 move to the proximal end side as indicated by an arrow a2.

  As shown in FIG. 2A, in the state where the hub 180 is pushed until it contacts the proximal end of the unit connector 170, that is, in the state where the hub 180 is pushed most distally, the distal end member 160, the imaging core 150 and the tip of the drive shaft 140 protrude from the tip opening 111 of the sheath 110. At this time, the tip of the inner shaft 130 reaches the vicinity of the relay connector 190.

  As shown in FIG. 2 (B), a connector 131 for preventing disconnection is provided at the tip of the inner shaft 130. The connector 131 for preventing disconnection has a function of preventing the inner shaft 130 from coming out of the outer tube 120. The connector 131 for preventing disconnection is a predetermined position on the inner wall of the unit connector 170 when the hub 180 is pulled most proximally, that is, when the inner shaft 130 is most pulled out from the outer tube 120 and the unit connector 170. It is configured to be caught on. When the hub 180 is pulled to the most proximal side as described above, the imaging core 150 and the drive shaft 140 are housed in the sheath 110, and as shown in FIG. The distal end portion of the coil 161 protrudes from the distal end opening portion 111 of the sheath 110. In order to prevent the inner shaft 130 from coming out of the outer tube 120, it is not always necessary to provide the connector 131 for preventing the inner shaft 130 from coming off. For example, the tip of the inner shaft 130 may be processed so as not to come out of the outer tube 120, and the inner shaft 130 may be prevented from coming out of the outer tube 120.

  As shown in FIG. 3A, the sheath 110 is constituted by a tubular member having a single lumen (hereinafter referred to as “working lumen 112”). A distal end opening 111 is formed at the distal end of the sheath 110.

  The sheath 110 is formed of a flexible material, and the material is not particularly limited. Various thermoplastic elastomers such as fluorinated rubber, fluororubber, chlorinated polyethylene, etc., and those in which one or a combination of two or more of these (polymer alloy, polymer blend, laminate, etc.) are used. it can. A hydrophilic lubricating coating layer that exhibits lubricity when wet can be disposed on the outer surface of the sheath 110.

  The drive shaft 140 includes a flexible tube body 141 and a signal line 142 inserted through the tube body 141. The drive shaft 140 is provided in the working lumen 112 of the sheath 110 so as to be movable forward and backward.

  The tubular body 141 can be constituted by, for example, a multilayer coil having different winding directions around the axis. Examples of the constituent material of the coil include stainless steel and Ni—Ti (nickel / titanium) alloy.

  The signal line 142 can be configured by, for example, a twisted pair cable or a coaxial cable.

  The imaging core 150 transmits an ultrasonic wave (corresponding to “examination wave”) to the living body lumen and receives an ultrasonic wave reflected from the living body lumen (corresponding to “transmission / reception unit”). And a housing 152 for holding the ultrasonic transducer 151.

  The ultrasonic transducer 151 is electrically connected to an electrode terminal 182 (see FIG. 3B) described later via a signal line 142.

  The ultrasonic transducer 151 is not particularly limited as long as it can transmit and receive ultrasonic waves. For example, a piezoelectric material such as ceramics or quartz can be used.

  The housing 152 is configured by a cylindrical member. An ultrasonic transducer 151 is accommodated in the housing 152. The portion of the housing 152 that faces the ultrasonic wave transmission / reception region of the ultrasonic transducer 151 is cut out to form an opening 152a.

  A proximal end side of the housing 152 is fixed to the drive shaft 140. The fixing method is not particularly limited, and for example, a soldering or other soldering method or a bonding method using an adhesive can be used.

  As shown in FIG. 4, the tip member 160 includes a coil 161 that extends along the axial direction, a core member 162 that extends along the axial direction inside the coil 161, and a convex shape at the tip of the coil 161. And a fixing portion 163 that fixes the core material 162 to the coil 161.

  The coil 161 can be deformed along a meandering or curved living body lumen, protrudes from the distal end opening 111 of the sheath 110, and has a function of guiding the movement of the sheath 110 in the living body lumen. This eliminates the need for the sheath 110 to be delivered to the lesion along the guide wire. As a result, there is no need to provide a guide wire lumen at the distal end portion of the sheath 110, the outer diameter of the distal end portion of the sheath 110 can be made relatively small, and the flexibility can be made relatively high.

  The coil 161 is preferably formed of a material having X-ray contrast properties. Examples of such a material include tungsten, gold, platinum, and the like.

  In the present embodiment, the core member 162 includes a tapered portion 162a that is tapered toward the distal end side, and a flat plate portion 162b that is formed at the distal end of the tapered portion 162a. By having the tapered portion 162a, the rigidity of the tip member 160 can be gradually reduced toward the tip side, and good flexibility can be obtained at the tip portion. The flat plate portion 162b can be formed by press molding, for example. The surgeon can shape (reshape) the tip member 160 into a desired shape by deforming the flat plate portion 162b. The core material 162 does not necessarily include the tapered portion 162a and the flat plate portion 162b. For example, the core material 162 may be configured by a rod-shaped member having a constant outer shape from the proximal end side toward the distal end side.

  The core material 162 is preferably formed of a material having a certain degree of flexibility and rigidity, and examples of such a material include stainless steel, spring steel, titanium, tungsten, tantalum, and nickel. -Metals such as superelastic alloys such as titanium alloys, hard plastics such as polyimide, polyamide, polyester, polycarbonate, glass fiber, and composites thereof.

  The proximal end portions of the coil 161 and the core material 162 are fixed to the distal end portion of the housing 152. The fixing method is not particularly limited, and for example, a method such as brazing such as brazing or soldering or adhesion using an adhesive can be used.

  The fixing portion 163 can be formed by, for example, brazing the tip portions of the coil 161 and the core material 162. The brazing material is preferably formed of a material having biocompatibility. Examples of such a material include silver brazing and gold brazing.

  As shown in FIGS. 3A and 5, the diagnostic imaging catheter 100 further includes a holding portion 113 provided at the distal end portion of the sheath 110. The holding unit 113 holds the tip member 160 with respect to the sheath 110 as shown in FIG. 6B when the tip member 160 is positioned at the tip opening 111 of the sheath 110. In addition, in the state where the distal end portion of the distal end member 160, the imaging core 150, and the drive shaft 140 protrudes from the distal end opening 111, the holding portion 113, as shown in FIG. 140 is held.

  As shown in FIG. 5, the holding portion 113 according to this embodiment includes a wall portion 113 b in which a slit 113 a is formed and covers the working lumen 112 of the sheath 110 in a direction intersecting the axial direction.

  The slit 113a has a cross shape in which two linear cuts intersect. The cut lengths L1 and L2 of the slit 113a are formed such that the drive shaft 140, the imaging core 150, and the tip member 160 can be inserted into the slit 113a. The shape of the slit 113a is not particularly limited as long as the drive shaft 140, the imaging core 150, and the tip member 160 can be inserted into the slit 113a. For example, the slit 113a has a Y shape in which three linear cuts intersect at the center. You may have.

  In the present embodiment, the wall portion 113 b is fixed to the distal end surface of the sheath 110. However, the fixing position of the wall portion 113b is not particularly limited as long as it can cover the cross section intersecting the axial direction of the working lumen 112 at the distal end portion of the sheath 110. For example, the fixing portion is fixed to the inner surface of the sheath 110. It may be. In this case, the wall 113b is preferably fixed to the inner surface within 1 mm from the distal end of the sheath 110.

  The wall 113b is preferably formed of a flexible material. Examples of such a material include styrene, polyolefin, polyurethane, polyester, polyamide, polyimide, polybutadiene, Examples include various thermoplastic elastomers such as transpolyisoprene, fluororubber, chlorinated polyethylene, etc., and combinations of one or more of these (polymer alloys, polymer blends, laminates, etc.) Can be used.

  As shown in FIG. 3B, the hub 180 includes a hub body 181 having a hollow shape, and electrode terminals 182 and a rotor 183 that are mechanically and electrically connected to an external device 200 described later. Than the connector 184, the port 185 communicating with the inside of the hub body 181, the direction confirmation protrusions 186 a and 186 b for confirming the orientation of the hub 180 when connecting to the external device 200, and the port 185 A seal member 187 that seals the base end side, a connection pipe 188 that holds the drive shaft 140, and a bearing 189 that rotatably supports the connection pipe 188 are provided.

  An inner shaft 130 is connected to the distal end portion of the hub body 181. The drive shaft 140 is drawn from the inner shaft 130 inside the hub body 181. A protective tube 132 is disposed between the inner shaft 130 and the drive shaft 140. The protective tube 132 has a function of suppressing vibration (flapping) of the drive shaft 140 that occurs during pullback operation.

  In order to transmit the rotation of the rotor 183 to the drive shaft 140, the connection pipe 188 holds the drive shaft 140 at the end opposite to the rotor 183 (the tip of the connection pipe 188). A signal line 142 (see FIG. 3A) is inserted into the connection pipe 188, and one end of the signal line 142 is connected to the electrode terminal 182 and the other end is connected to the ultrasonic transducer 151. A reception signal in the ultrasonic transducer 151 is transmitted to the external device 200 via the electrode terminal 182, subjected to predetermined processing, and displayed as an image.

  With reference to FIG. 1, the diagnostic imaging catheter 100 is connected to and driven by an external device 200 via a connector portion 184 provided on the proximal end side of the hub 180.

  The external device 200 includes a motor 200a that is a power source for rotating the drive shaft 140, a motor 200b that is a power source for moving the drive shaft 140 in the axial direction, and a rotational motion of the motor 200b as an axial motion. It has a drive unit 210 including a ball screw 200c for conversion, a monitor 220 for displaying the acquired image, and a control unit 230 for controlling them.

  Next, a method for using the diagnostic imaging catheter 100 will be described.

  Referring to FIGS. 1 and 6, as a first example of a method for using imaging diagnostic catheter 100, an over-the-wire type penetration catheter 300 (a relatively small-diameter catheter device) is applied to lesion N where stenosis has progressed. Etc.) to secure the insertion passage, the sheath 110 of the diagnostic imaging catheter 100 is inserted into the lumen 301 of the penetrating catheter 300 and moved to acquire an image of the lesion N.

  When using the diagnostic imaging catheter 100, the surgeon connects the external device 200 to the connector portion 184 of the diagnostic imaging catheter 100 as shown in FIG. 1. Thereafter, the surgeon connects the syringe S containing the priming liquid to the port 185 and pushes the pusher of the syringe S to fill the sheath 110 with the priming liquid.

  Prior to inserting the diagnostic imaging catheter 100 into the living body lumen, the surgeon inserts the guide wire W into the lesion N as shown in FIG. Then, the penetrating catheter 300 is inserted into the lesion N, and an insertion path of the diagnostic imaging catheter 100 is secured in the lesion N. Note that a tapered portion 302 is provided at the distal end of the penetrating catheter 300 so that the penetrating catheter 300 can be more smoothly inserted into the lesion N.

  Next, the surgeon removes the guide wire W from the living body.

  Next, the operator performs an operation of pulling the hub 180 to the most proximal end side, and the sheath 110 is pulled in a state where the distal end portion of the coil 161 protrudes from the distal end opening portion 111 as shown in FIG. It is inserted into the lumen 301 of the penetrating catheter 300 and delivered to the vicinity of the lesion N. Since the guide wire lumen is not provided at the distal end portion of the sheath 110, the outer diameter is relatively small and the flexibility is relatively high. Therefore, the sheath 110 can be smoothly moved in the penetration catheter 300. .

  The sheath 110 is guided by the coil 161 of the distal end member 160 and moves while following the meandering or curved penetrating catheter 300 along the blood vessel. At this time, the surgeon can further increase the flexibility of the distal end portion of the diagnostic imaging catheter 100 by performing an operation of pushing the hub 180 toward the distal end to increase the axial projection length of the coil 161. . In addition, since the distal end member 160 includes the fixing portion 163 that is curved in a convex shape, it is possible to prevent a situation in which the inner surface of the penetrating catheter 300 is damaged when the sheath 110 is moved.

  Next, as shown in FIG. 6C, the surgeon moves the ultrasonic transducer 151 to a desired image acquisition start position in the penetrating catheter 300 (the position on the distal end side of the lesion N in the figure). The hub 180 is pushed to the front end side so as to be disposed at the top. At this time, since the distal end member 160, the imaging core 150, and the drive shaft 140 move in the penetration catheter 300, the ultrasonic transducer 151 can be disposed in the lesioned part without expanding the lesioned part N.

  In this way, instead of moving the entire diagnostic imaging catheter 100 including the sheath 110, the penetrating catheter is moved by moving the tip member 160, the imaging core 150, and the drive shaft 140 having a relatively small outer diameter. The ultrasonic transducer 151 can be arranged in a region where 300 taper portions 302 are provided. For this reason, as shown in FIG. 6C, an image can be acquired also for a lesioned part N located in a region overlapping with the tapered part 302.

  At this time, even if the distal end member 160 protrudes from the opening 303 at the distal end of the penetrating catheter 300 and comes into contact with the blood vessel wall or the lesioned portion N, the distal end member 160 is fixed by the convexly fixed portion 163. It is possible to prevent the blood vessel wall and the lesioned part N from being damaged. Further, since the tip member 160 includes the core material 162 and the fixing portion 163, the coil 161 can be prevented from being damaged by contact or the like.

  Next, as shown in FIG. 6D, a pullback operation is performed to acquire a diagnostic image. At this time, the ultrasonic transducer 151 transmits and receives ultrasonic waves while rotating to the proximal end side together with the drive shaft 140.

  Then, the control unit 230 controls the motor 200a shown in FIG. 1 and controls the rotation of the drive shaft 140 around the axis. The control unit 230 also controls the motor 200b to control the movement of the drive shaft 140 in the axial direction. Based on a signal sent from the control unit 230, the ultrasonic transducer 151 transmits an ultrasonic wave into the body. A signal corresponding to the reflected wave received by the ultrasonic transducer 151 is sent to the control unit 230 of the external device 200 via the drive shaft 140. The control unit 230 generates a tomographic image of the blood vessel based on the signal sent from the ultrasonic transducer 151 and displays the generated image on the monitor 220. Since the guide wire W has been removed, an image free from defects due to the guide wire W can be acquired.

  Thus, the diagnostic imaging catheter 100 can acquire an image at a position protruding from the sheath 110. For this reason, compared with the case where an image is acquired in the position which the sheath 110 and the penetration catheter 300 overlap, the quality of an image can be kept comparatively favorable.

  Further, when the imaging core 150 is protruded from the distal end opening 111 and the pullback operation is performed, the holding unit 113 holds the drive shaft 140 with respect to the sheath 110, and thus the flapping of the imaging core 150 can be suppressed. In addition, the wall portion 113b of the holding portion 113 can prevent blood or the like from flowing into the sheath 110 when the inside of the sheath 110 becomes a negative pressure with respect to the outside of the sheath 110 by a pull back operation.

  Next, the operator performs an operation of pulling the hub 180 to the most proximal end, and after the imaging core 150 and the drive shaft 140 are accommodated in the sheath 110, the diagnostic imaging catheter 100 is removed from the living body.

  Next, referring to FIG. 7, as a second example of the method of using the diagnostic imaging catheter 100, diagnostic imaging is performed in the lumen 401 of the over-the-wire balloon catheter 400 inserted into the narrowed lesion N. A method for inserting and moving the catheter 100 and acquiring a diagnostic image will be described. Note that the priming and pullback operations are the same as in the first example, and thus the description thereof is omitted.

  The surgeon performs a priming operation of the diagnostic imaging catheter 100 when using the diagnostic imaging catheter 100.

  Prior to inserting the diagnostic imaging catheter 100 into the living body lumen, the surgeon inserts the guide wire W into the lesion N as shown in FIG. Then, the balloon catheter 400 is inserted through the lesion N. At this time, the balloon 402 of the balloon catheter 400 is not expanded.

  Next, the surgeon removes the guide wire W from the living body.

  Next, as shown in FIG. 7B, the operator performs an operation of pulling the hub 180 to the most proximal side, and the sheath 110 is moved in a state where the distal end portion of the coil 161 protrudes from the distal end opening portion 111. It is inserted into the lumen 401 of the balloon catheter 400 and moved to the periphery of the lesion N.

  Next, as shown in FIG. 7C, the surgeon moves the ultrasonic transducer 151 to a desired image acquisition start position in the balloon catheter 400 (in the figure, a position closer to the distal side than the lesioned part N). The hub 180 is pushed to the front end side so as to be disposed at the top.

  Next, as shown in FIG. 7D, a pullback operation is performed while the balloon 402 of the balloon catheter 400 is expanded to acquire a diagnostic image. Thereby, the balloon 402 can be expanded while confirming the degree of expansion of the lesion N. For this reason, it becomes possible to adjust the expansion amount of the balloon 402, and it is possible to prevent the balloon 402 from being over-expanded to cause perforation or the like in the lesion N.

  Next, the operator performs an operation of pulling the hub 180 to the proximal end side, houses the imaging core 150 and the drive shaft 140 in the sheath 110, and removes the diagnostic imaging catheter 100 from the living body.

  In the second example, the case where the image is acquired while the balloon 402 of the balloon catheter 400 is expanded has been described. However, in order to confirm the state of the lesion N before the balloon 402 is expanded, image diagnosis is performed. A diagnostic image may be acquired by the catheter 100 for use.

  As described above, the diagnostic imaging catheter 100 according to this embodiment includes the distal end opening 111, the sheath 110 to be inserted into the living body lumen, the rotation within the sheath 110, and the forward and backward movement in the axial direction of the sheath 110. A drive shaft 140 that is movably provided, an ultrasonic transducer 151 that can transmit and receive ultrasonic waves, and a housing 152 that holds the ultrasonic transducer 151, an imaging core 150 that is provided at the tip of the drive shaft 140, and a living body A distal end member 160 that includes a coil 161 that guides the movement of the sheath 110 in the lumen and is provided at the distal end of the imaging core 150. The distal end portion of the coil 161 can project from the distal end opening 111 of the sheath 110 as the drive shaft 140 moves toward the distal end side.

  According to the diagnostic imaging catheter 100 configured as described above, the distal end portion of the coil 161 protruding from the distal end opening portion 111 of the sheath 110 functions to guide the movement of the sheath 110 within the living body lumen. There is no need to deliver 110 along the guide wire to the lesion. Therefore, it is not necessary to provide a guide wire lumen at the distal end portion of the sheath 110, and the outer diameter of the distal end portion of the sheath 110 can be made relatively small and flexibility can be increased. Thereby, for example, the diagnostic imaging catheter 100 can be inserted and moved into the lumen of another medical device such as the penetrating catheter 300 or the balloon catheter 400 previously inserted into the lesioned part. Therefore, the diagnostic imaging catheter 100 can be delivered to the lesion more reliably, and the diagnostic imaging catheter 100 can be placed in the lesion without pushing the lesion.

  The diagnostic imaging catheter 100 further includes a holding portion 113 provided at the distal end portion of the sheath 110 and capable of holding the drive shaft 140 with respect to the sheath 110. When the pullback operation is performed by causing the ultrasonic transducer 151 to protrude from the distal end opening portion 111, the holding portion 113 holds the drive shaft 140 with respect to the sheath 110, and thus fluttering of the imaging core 150 can be suppressed. As a result, the quality of the diagnostic image can be kept relatively good.

  The holding portion 113 includes a wall portion 113b in which a slit 113a into which the drive shaft 140 can be inserted is formed and is arranged so as to cover the working lumen 112 of the sheath 110. For this reason, it is possible to prevent the inflow of body fluid such as blood into the sheath 110 when the pullback operation is performed while allowing the drive shaft 140 to be inserted.

  The tip member 160 includes a core member 162 extending along the axial direction inward of the coil 161, and a fixing portion 163 that is curved convexly at the tip end of the coil 161 and fixes the core member 162 to the coil 161. It is equipped with. The core material 162 and the fixing part 163 can prevent the coil 161 from being damaged when it comes into contact with the inner surface of another medical device, a living body lumen, a lesioned part, or the like. Further, when the distal end member 160 comes into contact with the inner surface, biological lumen, lesioned part, etc. of another medical device by the fixing part 163, the inner surface, biological lumen, lesioned part, etc. of the other medical device is removed. Injury can be prevented.

  The diagnostic imaging catheter 100 further includes a hub 180 that is provided on the proximal end side of the drive shaft 140 and can be pushed and pulled along the axial direction. When the hub 180 is pushed most distally, In a state where the ultrasonic transducer 151 protrudes from the distal end opening 111 of the sheath 110 and the hub 180 is pulled to the most proximal side, the imaging core 150 and the drive shaft 140 are accommodated in the sheath 110, and the coil The distal end portion of 161 protrudes from the distal end opening portion 111 of the sheath 110. For this reason, the ultrasonic transducer 151 is protruded from the distal end opening 111 of the sheath 110 or the coil 161 is opened to the distal end of the sheath 110 simply by pushing the hub 180 to the most distal end or pulling it to the most proximal end. It becomes possible to project from the part 111, and the position adjustment of the ultrasonic transducer 151 and the coil 161 becomes easy.

  As described above, the diagnostic imaging catheter according to the present invention has been described through the embodiments, but the present invention is not limited to the configuration described in the embodiments, and may be appropriately changed based on the description of the scope of claims. Is possible.

  For example, in the above-described embodiment, the imaging diagnostic catheter used in the intravascular ultrasonic diagnostic method (IVUS) is exemplified as an application target of the imaging diagnostic catheter according to the present invention. For imaging diagnostic catheters used for diagnostic methods (Optical Coherence Tomography: OCT), hybrid type (dual type) imaging diagnostic catheters that can be used for both intravascular ultrasound diagnostic methods and optical coherence tomographic diagnostic methods, etc. It is also possible to apply.

  Further, for example, in the state where the hub is pulled to the most proximal side and the state where the hub is pushed to the most distal side, the arrangement of the tip member, the imaging core and the drive shaft is set at any position. There is no particular limitation as long as at least the tip of the coil can protrude from the tip opening of the sheath. For example, the coil may be completely accommodated in the sheath with the hub pulled most proximally, or the coil may protrude completely from the distal end opening of the sheath. Further, for example, the imaging core and the drive shaft may be housed in the sheath while the hub is pushed most distally, and the distal end portion of the coil may protrude from the distal end opening portion of the sheath.

  For example, in the above-described embodiment, the case where the image is acquired at the position where the ultrasonic transducer protrudes from the distal end opening of the sheath has been described. However, the position where the image is acquired is not limited to the position protruding from the sheath. For example, an image may be acquired within the sheath, or an image may be acquired both inside and outside the sheath.

  Further, for example, in the above-described embodiment, the method of inserting an image diagnostic catheter into an over-the-wire type penetration catheter or balloon catheter has been described as an example, but medical treatment used in combination with an image diagnostic catheter is used. The device for use is not particularly limited, and for example, it can be used in combination with an over-the-wire type debulking device.

  In addition, for example, in the above-described embodiment, the case where the holding portion includes the wall portion in which the slit is formed has been described. However, the holding portion is not particularly limited as long as the driving shaft can be held. You may comprise the through-hole which can be penetrated and is comprised by the elastic member which covers a working lumen.

100 catheter for diagnostic imaging,
110 sheath,
111 Tip opening,
112 Working lumen (lumen),
113 holding part,
113a slit,
113b walls,
140 drive shaft,
150 Imaging Core,
151 ultrasonic transducer (transceiver),
152 housing,
160 tip member,
161 coils,
162 core material,
163 fixing part,
180 hubs,
200 External device,
300 penetration catheter,
400 balloon catheter.

Claims (5)

A sheath having a tip opening and inserted into a biological lumen;
A drive shaft provided in the sheath so as to be rotatable and movable back and forth in the axial direction of the sheath;
An imaging core provided at a distal end portion of the drive shaft, comprising a transmission / reception unit capable of transmitting / receiving an inspection wave and a housing holding the transmission / reception unit;
A coil for guiding the movement of the sheath in the living body lumen, and a tip member provided at the tip of the imaging core,
The catheter for diagnostic imaging, wherein the distal end portion of the coil can project from the distal end opening portion of the sheath as the drive shaft moves toward the distal end side.   The diagnostic imaging catheter according to claim 1, further comprising a holding portion provided at a distal end portion of the sheath and capable of holding the drive shaft with respect to the sheath.   The diagnostic imaging catheter according to claim 2, wherein the holding portion includes a wall portion formed with a slit through which the drive shaft can be inserted and arranged to cover the lumen of the sheath.   The tip member includes a core member that extends along the axial direction inward of the coil, and a fixing portion that curves convexly at the tip of the coil and fixes the core member to the coil. Item 4. The diagnostic imaging catheter according to any one of Items 1 to 3. A hub provided on the base end side of the drive shaft and configured to be pushed and pulled along the axial direction;
When the hub is pushed to the most distal side, the transmission / reception unit protrudes from the distal end opening of the sheath, and when the hub is pulled to the most proximal side, the imaging core and the drive shaft are connected to the sheath. The diagnostic imaging catheter according to any one of claims 1 to 4, wherein the catheter is housed in the distal end and the distal end of the coil protrudes from the distal end opening of the sheath.