Patent Description:
In recent years, as a medical apparatus used to acquire a diagnostic image for diagnosing a diseased site in a living body, a dual-type image diagnosis catheter having functions of both an intra vascular ultra sound (IVUS) diagnosis method and an optical coherence tomography (OCT) diagnosis method has been developed (refer to PTL <NUM> below).

The dual-type image diagnosis catheter has a drive shaft provided with an ultrasound transmitter and receiver and an optical transmitter and receiver at a distal end, and a sheath provided with a lumen into which a drive shaft is rotatably inserted. When obtaining a tomographic image with the image diagnosis catheter, the sheath is inserted into a biological lumen, and moved rearward while rotating the drive shaft within the sheath. Therefore, an operation for moving the drive shaft from a distal end side to a proximal end side, so-called a pull-back operation (thinning operation), or a push-in operation for pushing the drive shaft toward the distal end side is performed. Simultaneously with this operation, the ultrasound transmitter and receiver transmits an ultrasound toward a wall of the biological lumen and receives a reflected wave reflected on the wall of the biological lumen. In addition, the optical transmitter and receiver simultaneously transmits light toward the wall of the biological lumen and receives a reflected light reflected on the wall of the biological lumen.

The dual-type image diagnosis catheter disclosed in PTL <NUM> is not provided with a mechanism for fixing a relative position of the optical transmitter and receiver with respect to the ultrasound transmitter and receiver. Therefore, it is difficult to maintain a transmission direction of light transmitted from the optical transmitter and receiver in a fixed direction with respect to a transmission direction of the ultrasound transmitted from the ultrasound transmitter and receiver. Therefore, it is difficult to maintain the relative position of light with respect to the ultrasound of each image diagnosis catheter within a desired tolerance at the time of manufacture (assemble), for example.

Therefore, an object of the present invention is to provide an image diagnosis catheter capable of maintaining a transmission direction of light in a fixed direction with respect to a transmission direction of the ultrasound.

According to the image diagnosis catheter of the present invention, a relative position of the optical transmitter and receiver with respect to the ultrasound transmitter and receiver is fixed. Therefore, a transmission direction of light can be kept in a fixed direction with respect to a transmission direction of the ultrasound.

Note that the following description does not limit the technical scope and terms used in the aspects. In addition, the dimensional ratios in the drawings are exaggerated for convenience of description, and may differ from actual ratios.

<FIG> is a plan view illustrating a state where an external device <NUM> is connected to an image diagnosis catheter <NUM> according to the present embodiment. <FIG> is a diagram schematically illustrating an overall configuration of the image diagnosis catheter <NUM> according to the embodiment. <FIG> is a diagram illustrating a configuration of a distal end of the image diagnosis catheter <NUM> according to the embodiment. <FIG> is a diagram illustrating a configuration of a proximal end of the image diagnosis catheter <NUM> according to the embodiment. In addition, <FIG> are diagrams for describing a positioning mechanism of an ultrasound transmitter and receiver 145a and an optical transmitter and receiver 145b, which are main parts of the image diagnosis catheter <NUM> according to the embodiment. In addition, <FIG> are diagrams for describing an example of use of the image diagnosis catheter <NUM> according to the embodiment.

The image diagnosis catheter <NUM> according to the present embodiment is a dual-type image diagnosis catheter having both functions of an intra vascular ultra sound (IVUS) diagnosis method and an optical coherence tomography (OCT) diagnosis method. Note that, in the dual-type image diagnosis catheter <NUM>, there are three types of 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 IVUS and OCT. These modes can be switched and used. As illustrated in <FIG>, the image diagnosis catheter <NUM> is driven by being connected to the external device <NUM>.

The image diagnosis catheter <NUM> will be described with reference to <FIG>.

As illustrated in <FIG>, <FIG>, briefly, the image diagnosis catheter <NUM> includes a sheath <NUM> to be inserted into a body-cavity of a living body, an outer tube <NUM> provided on a proximal end of the sheath <NUM>, an inner shaft <NUM> inserted into the outer tube <NUM> so as to be movable forward and backward, a drive shaft <NUM> rotatably provided in the sheath <NUM> having a signal transmitter and receiver <NUM> transmitting and receiving signals at a distal end, a unit connector <NUM> provided on the proximal end of the outer tube <NUM> and configured to receive the inner shaft <NUM>, and a hub <NUM> provided on the proximal end of the inner shaft <NUM>.

In the description of the specification, a side inserted into the body-cavity of the image diagnosis catheter <NUM> is referred to as a distal end or a distal end side. A hub <NUM> side provided in the image diagnosis catheter <NUM> is referred to as a proximal end or a proximal end side. An extending direction of the sheath <NUM> is referred to as an axial direction.

As illustrated in <FIG>, the drive shaft <NUM> extends to the inside of the hub <NUM> through the sheath <NUM>, the outer tube <NUM> connected to the proximal end of the sheath <NUM>, and the inner shaft <NUM> inserted into the outer tube <NUM>.

The hub <NUM>, the inner shaft <NUM>, the drive shaft <NUM>, and the signal transmitter and receiver <NUM> are connected to each other so as to move forward and backward integrally in the axial direction. Therefore, for example, when the hub <NUM> is pushed toward the distal end side, the inner shaft <NUM> connected to the hub <NUM> is pushed into the outer tube <NUM> and the unit connector <NUM>, and the drive shaft <NUM> and the signal transmitter and receiver <NUM> moves inside the sheath <NUM> toward the distal end side. For example, when the operation of pulling the hub <NUM> toward the proximal end side is performed, the inner shaft <NUM> is pulled out from the outer tube <NUM> and the unit connector <NUM> as illustrated by an arrow a1 in <FIG> and <FIG>. The drive shaft <NUM> and the signal transmitter and receiver <NUM> move inside the sheath <NUM> toward the proximal end side as indicated by an arrow a2.

As illustrated in <FIG>, when the inner shaft <NUM> is pushed most into the distal end side, a distal portion of the inner shaft <NUM> reaches the vicinity of a relay connector <NUM>. At this time, the signal transmitter and receiver <NUM> is located in the vicinity of the distal end of the sheath <NUM>. The relay connector <NUM> is a connector that connects the sheath <NUM> and the outer tube <NUM>.

As illustrated in <FIG>, a connector <NUM> for preventing disconnection is provided at the distal end of the inner shaft <NUM>. The connector <NUM> for preventing disconnection has a function of preventing the inner shaft <NUM> from coming out of the outer tube <NUM>. When the hub <NUM> is most pulled out toward the proximal end side, that is, when the inner shaft <NUM> is most pulled out from the outer tube <NUM> and the unit connector <NUM>, the connector <NUM> for preventing disconnection is configured to be caught at a predetermined position on an inner wall of the unit connector <NUM>.

As illustrated in <FIG>, the drive shaft <NUM> is provided with a flexible tubular body <NUM>, and an electric signal cable <NUM> (corresponding to "signal line") and an optical fiber <NUM> connected to the signal transmitter and receiver <NUM> are disposed therein. The tubular body <NUM> can be configured to include, for example, a multilayer coil having different winding directions around the axis. Examples of the material constituting the coil include stainless steel and Ni-Ti (nickel and titanium) alloy. In the present embodiment, the electric signal cable <NUM> is provided with two signal lines 142a and 142b that are electrically connected to electrode terminals 165a provided in a connector portion <NUM> described later.

The signal transmitter and receiver <NUM> includes the ultrasound transmitter and receiver 145a that transmits and receives the ultrasound and the optical transmitter and receiver 145b that transmits and receives light.

The ultrasound transmitter and receiver 145a is provided with a transducer, and has a function of transmitting the ultrasound based on a pulse signal into the body-cavity and receiving the ultrasound reflected from a biological tissue in the body-cavity. The ultrasound transmitter and receiver 145a is electrically connected to the electrode terminal 165a (refer to <FIG>) via the electric signal cable <NUM>.

As the transducer provided in the ultrasound transmitter and receiver 145a, for example, a piezoelectric material such as ceramics or quartz can be used.

The optical transmitter and receiver 145b continuously transmits a transmitted measurement light ML into the body-cavity and continuously receives a reflected light from the biological tissue in the body-cavity. The optical transmitter and receiver 145b is provided at the distal end of the optical fiber <NUM>, and has an optical element having a lens function for condensing light and a reflection function for reflecting light. Note that, in the present embodiment, the optical element is formed of a ball lens.

The signal transmitter and receiver <NUM> is accommodated in a housing <NUM>. The proximal end of the housing <NUM> is connected to the drive shaft <NUM>. The housing <NUM> has a shape in which an opening portion 146a is provided on a cylindrical surface of a cylindrical metal pipe so as not to hinder the progress of the ultrasound transmitted and received by the ultrasound transmitter and receiver 145a and light transmitted and received by the optical transmitter and receiver 145b. The housing <NUM> can be formed by, for example, laser processing. Note that the housing <NUM> may be formed by cutting from a metal mass, metallic powder injection molding (MIM) , or the like.

A distal member <NUM> is provided at the distal end of the housing <NUM>. The distal member <NUM> has a substantially hemispherical outer shape. The distal member <NUM> is formed in a hemispherical shape, so that friction and catching with the inner surface of the sheath <NUM> can be suppressed. Note that the distal member <NUM> may be formed of a coil, for example. In addition, the distal member <NUM> may not be provided at the distal end of the housing <NUM>.

The sheath <NUM> is provided with a lumen 110a into which the drive shaft <NUM> is inserted so as to be movable forward and backward. A guide wire insertion member <NUM> provided with a guide wire lumen 114a that is parallel to the lumen 110a provided in the sheath <NUM> and into which a second guide wire W to be described later can be inserted is attached to the distal portion of the sheath <NUM>. The sheath <NUM> and the guide wire insertion member <NUM> can be integrally formed by heat-welding or the like. The guide wire insertion member <NUM> is provided with a marker <NUM> having X-ray contrast properties. The marker <NUM> is formed of a metal pipe having high radiopacity such as Pt and Au. Note that, for the purpose of improving the mechanical strength, an alloy in which Ir is mixed with Pt aforementioned may be used. Furthermore, the marker <NUM> may be formed of a metal coil instead of a metal pipe.

A communication hole <NUM> that communicates the inside and the outside of the lumen 110a is formed at the distal portion of the sheath <NUM>. In addition, a reinforcing member <NUM> for firmly joining and supporting the guide wire insertion member <NUM> is provided at the distal portion of the sheath <NUM>. The reinforcing member <NUM> is formed with a communication passage 117a that communicates the inside of the lumen 110a disposed on the proximal end from the reinforcing member <NUM> and the communication hole <NUM>. Note that the reinforcing member <NUM> may not be provided at the distal portion of the sheath <NUM>.

The communication hole <NUM> is a priming solution discharge hole for discharging a priming solution. When the image diagnosis catheter <NUM> is used, priming processing of filling the sheath <NUM> with the priming solution is performed. For example, in a case where ultrasound SW is transmitted without filling the sheath <NUM> with the priming solution, due to a large difference in acoustic impedance between a matching layer disposed on the surface of the transducer of the ultrasound transmitter and receiver 145a and the air, the ultrasound SW is reflected at the interface between the matching layer and the air, and there is a possibility that the ultrasound SW cannot reach a wall of a biological lumen <NUM> deeply. On the other hand, by filling the sheath <NUM> with the priming solution, since the priming solution has an acoustic impedance value close to that of the matching layer, the ultrasound SW can reach the wall of the biological lumen <NUM> deeply. When performing the priming processing, the priming solution can be discharged to the outside from the communication hole <NUM> and the gas such as air can be discharged from the inside of the sheath <NUM> together with the priming solution.

The distal portion of the sheath <NUM>, which is the range in which the signal transmitter and receiver <NUM> moves in the axial direction of the sheath <NUM>, includes a window portion that is formed to have higher permeability of inspection waves such as light and an ultrasound than other portions.

The sheath <NUM>, the guide wire insertion member <NUM>, and the reinforcing member <NUM> are formed of a flexible material, the material is not particularly limited, and examples thereof include various thermoplastic elastomers such as styrene-based, polyolefin-based, polyurethane-based, polyester-based, polyamide-based, polyimide-based, polybutadiene-based, trans polyisoprene-based, fluorine rubber-based, and chlorinated polyethylene-based. One or a combination of two or more of these (polymer alloy, polymer blend, laminate, and the like) can also be used. Note that a hydrophilic lubricating coating layer that exhibits lubricity when wet can be disposed on the outer surface of the sheath <NUM>.

As illustrated in <FIG>, the hub <NUM> includes a hub main body <NUM> having a hollow shape, a connector case 165c connected to the proximal end of the hub main body <NUM>, a port <NUM> communicating with the inside of the hub main body <NUM>, projections 163a and 163b for determining the position (direction) of the hub <NUM> when connecting to the external device <NUM>, a connection pipe 164b holding the drive shaft <NUM>, a bearing 164c rotatably supporting the connection pipe 164b, a sealing member 164a preventing the priming solution from leaking from between the connection pipe 164b and the bearing 164c toward the proximal end side, and a connector portion <NUM> in which an electrode terminal 165a and an optical connector 165b connected to the external device <NUM> are disposed.

The inner shaft <NUM> is connected to the distal portion of the hub main body <NUM>. The drive shaft <NUM> is pulled out from the inner shaft <NUM> inside the hub main body <NUM>.

The port <NUM> is connected to an injection device S (refer to <FIG>) for injecting a priming solution when performing the priming processing. The injection device S is provided with a connector S1 connected to the port <NUM>, a tube S2 connected to the connector S1, a three-way stopcock S3 connected to the tube S2, and a first syringe S4 and a second syringe S5 which are connected to the three-way stopcock S3 and can inject the priming solution into the port <NUM>. The second syringe S5 has a larger capacity than that of the first syringe S4, and is a syringe used as an auxiliary in a case where the amount of the priming solution injected by the first syringe S4 is insufficient.

The connection pipe 164b holds the drive shaft <NUM> in order to transmit the rotation of the electrode terminal 165a and the optical connector 165b which are rotationally driven by the external device <NUM> to the drive shaft <NUM>. The electric signal cable <NUM> and the optical fiber <NUM> (refer to <FIG>) are inserted into the connection pipe 164b.

The connector portion <NUM> is provided with the electrode terminal 165a electrically connected to the electric signal cable <NUM> and the optical connector 165b connected to the optical fiber. A reception signal in the ultrasound transmitter and receiver 145a is transmitted to the external device <NUM> via the electrode terminal 165a, subjected to the predetermined processing, and displayed as an image. A reception signal in the optical transmitter and receiver 145b is transmitted to the external device <NUM> via the optical connector 165b, subjected to the predetermined processing, and displayed as an image.

Referring again to <FIG>, the image diagnosis catheter <NUM> is connected to the external device <NUM> and driven.

As aforementioned, the external device <NUM> is connected to the connector portion <NUM> provided on the proximal end of the hub <NUM>.

In addition, the external device <NUM> includes a motor 300a that is a power source for rotating the drive shaft <NUM>, and a motor 300b that is a power source for moving the drive shaft <NUM> in the axial direction. The rotational motion of the motor 300b is converted into axial motion by a direct motion conversion mechanism 300c connected to the motor 300b. As the direct motion conversion mechanism 300c, for example, a ball screw, a rack and pinion mechanism, or the like can be used.

The operation of the external device <NUM> is controlled by a control apparatus <NUM> electrically connected thereto. The control apparatus <NUM> includes a central processing unit (CPU) and a memory as main components. The control apparatus <NUM> is electrically connected to a monitor <NUM>.

Next, a positioning mechanism of the ultrasound transmitter and receiver 145a and the optical transmitter and receiver 145b in the housing <NUM> will be described with reference to <FIG>. Note that, in the following, a side of the housing <NUM> where the opening portion 146a is provided (upper side in <FIG>) is referred to as an "upper side". In addition, as illustrated in <FIG>, in a case where the image diagnosis catheter <NUM> is not inserted into the biological lumen <NUM>, a rotation axis in a state where the drive shaft <NUM> is straightened is indicated by Y. Note that, in a state where the image diagnosis catheter <NUM> is inserted into the biological lumen <NUM>, the rotation axis of the drive shaft can be bent along a bent shape of the biological lumen <NUM>.

The ultrasound transmitter and receiver 145a is attached to a backing member <NUM> as illustrated in <FIG>. The backing member <NUM> scatters and attenuates the ultrasound from the ultrasound transmitter and receiver 145a in the direction opposite to the opening portion 146a of the housing <NUM>. The backing member <NUM> is attached to an edge portion 146c that surrounds the opening portion 146a of the housing <NUM>. As aforementioned, the ultrasound transmitter and receiver 145a is fixed to the housing <NUM> via the backing member <NUM>. Note that a method of fixing the backing member <NUM> to the housing <NUM> is not particularly limited, and can be fixed by bonding with an adhesive, for example. As illustrated in <FIG>, the ultrasound transmitter and receiver 145a is fixed to the housing <NUM> so that the ultrasound SW is transmitted in a direction inclined toward the proximal end side with respect to a radiation direction (radial direction R) of the drive shaft <NUM>.

The optical transmitter and receiver 145b is fixed to the housing <NUM> via a positioning member <NUM> as illustrated in <FIG>. Therefore, a relative position of the optical transmitter and receiver 145b with respect to the ultrasound transmitter and receiver 145a can be determined. As a result, a transmission direction of the measurement light ML transmitted from the optical transmitter and receiver 145b can be determined in a fixed direction with respect to a direction of the ultrasound SW transmitted from the ultrasound transmitter and receiver 145a. Therefore, for example, at the time of manufacture (assemble), the relative positional relationship between the ultrasound and light of each image diagnosis catheter can be suitably maintained within a desired tolerance.

Note that, in the present embodiment, the positioning member <NUM> fixes the position of the optical transmitter and receiver 145b so that the ultrasound SW transmitted from the ultrasound transmitter and receiver 145a intersects with the measurement light ML transmitted from the optical transmitter and receiver 145b.

The positioning member <NUM> is fixed to the inner surface of the housing <NUM> on the proximal end of the housing <NUM>. As illustrated in <FIG>, the positioning member <NUM> has a cylindrical outer shape. As illustrated in <FIG>, the positioning member <NUM> is provided with an optical fiber fixing portion <NUM> that fixes the optical fiber <NUM>, an electric signal cable insertion portion <NUM> through which the electric signal cable <NUM> can be inserted, and a recess <NUM> for adjusting a position in a circumferential direction of the positioning member <NUM> with respect to the housing <NUM>.

The optical fiber fixing portion <NUM> is provided with a concave groove portion 2221a into which the optical fiber <NUM> can be fitted. As illustrated in <FIG>, the groove portion 221a penetrates the positioning member <NUM> in the axial direction. The optical transmitter and receiver 145b is connected to the distal end of the optical fiber <NUM> disposed so as to be inserted through the groove portion 221a in the axial direction. As aforementioned, the positioning member <NUM> fixes the position of the optical transmitter and receiver 145b by fixing the optical fiber <NUM>.

As illustrated in <FIG>, the positioning member <NUM> is provided in the housing <NUM> so that the optical transmitter and receiver 145b is positioned on the rotation axis Y of the drive shaft <NUM> when viewed from above the housing <NUM>. Therefore, the ultrasound transmitter and receiver 145a and the optical transmitter and receiver 145b are positioned side by side on the rotation axis Y of the drive shaft <NUM> when viewed from above the housing <NUM>. In addition, as illustrated in <FIG>, the positioning member <NUM> is fixed to the housing <NUM> so that the curved surface of the ball lens constituting the optical transmitter and receiver 145b faces upward of the housing <NUM>. The optical transmitter and receiver 145b connected to the distal end of the optical fiber <NUM> transmits the measurement light ML in a direction inclined toward the distal end side with respect to the radial direction R of the drive shaft <NUM>. Therefore, the ultrasound SW transmitted from the ultrasound transmitter and receiver 145a intersects with the measurement light ML transmitted from the optical transmitter and receiver 145b.

Note that, as illustrated in <FIG>, the ultrasound SW transmitted from the ultrasound transmitter and receiver 145a propagates outward of the housing <NUM> so as to spread slightly. In addition, similarly, the measurement light ML transmitted from the optical transmitter and receiver 145b also propagates outward from the housing <NUM> so as to spread slightly. In this specification, "ultrasound SW transmitted from the ultrasound transmitter and receiver 145a intersects with measurement light ML transmitted from the optical transmitter and receiver 145b" means that at least a propagation region of the ultrasound SW propagating with spread (region illustrated in light gray in the drawing) intersects with a propagation region of the measurement light ML with spread (region illustrated in dark gray in the drawing).

In the present embodiment, as illustrated in <FIG>, a transmission direction D1 of the central portion of the ultrasound SW transmitted from the ultrasound transmitter and receiver 145a toward the outside of the housing <NUM> (wall of the biological lumen 900b) are configured to intersect with a transmission direction D2 (optical axis direction) of the central portion of the measurement light ML transmitted from the optical transmitter and receiver 145b toward the outside of the housing <NUM> (wall of the biological lumen 900b) at a point P where a distance from the outer surface of the housing <NUM> is a length L1. Therefore, for example, in a case where the image diagnosis catheter <NUM> is inserted into the biological lumen <NUM>, when the image diagnosis catheter <NUM> is disposed at a position where the distance from the outer surface of the housing <NUM> to the wall of the biological lumen 900b is approximately the length L1, as illustrated in <FIG>, an inspection region of the ultrasound SW (region illustrated in light gray) and an inspection region of the measurement light ML (region illustrated in dark gray) on the wall of the biological lumen 900b can overlap each other. Note that the distance L1 can be appropriately set according to the average diameter of the biological lumen <NUM> into which the image diagnosis catheter <NUM> is inserted.

Note that the ultrasound SW and the measurement light ML have a spread to some extent. Therefore, when the measurement light ML is applied to at least any portion of the region (region illustrated in light gray) where the ultrasound SW hits on the wall of the biological lumen 900b, the inspection region of the ultrasound SW and the inspection regions of the measurement light ML can overlap each other. Therefore, even when the diameter of the biological lumen <NUM> changes depending on the position in the extending direction of the biological lumen <NUM>, the inspection region of the ultrasound SW and the inspection region of the measurement light ML can overlap each other.

In addition, in the present embodiment, as illustrated in <FIG>, an interlock portion 143a is covered with a protective cover <NUM> in order to protect the interlock portion 143a of the optical fiber <NUM> and the optical transmitter and receiver 145b. Since the signal transmitter and receiver <NUM>, the electric signal cable <NUM>, the optical fiber <NUM>, the positioning member <NUM>, and the like are disposed in the housing <NUM>, the housing <NUM> preferably has a larger inner diameter r2 (refer to <FIG>). However, in order to maintain the slidability of the sheath <NUM> in the biological lumen <NUM> suitably, the housing <NUM> preferably has a small outer diameter, and it is necessary to secure a thickness to some extent in order to ensure strength. Therefore, there is a limit in forming the inner diameter r2 (refer to <FIG>) of the housing <NUM> to be large. Therefore, there is a limit in forming the outer diameter of the positioning member <NUM> accommodated in the housing <NUM> to be large. Therefore, when the optical fiber <NUM> is disposed so that the axial center of the optical fiber <NUM> covered with the protective cover <NUM> is positioned on the rotation axis Y of the drive shaft <NUM>, due to the outer diameter r1 of the optical fiber <NUM> including the protective cover <NUM>, it is difficult to secure a space (electric signal cable insertion portion <NUM>) for disposing the electric signal cable <NUM> (two signal lines 142a and 142b) having a fixed outer diameter r3. Therefore, the groove portion 221a is provided at a position displaced in the transmission direction D2 of the measurement light ML transmitted from the optical transmitter and receiver 145b with respect to the rotation axis Y of the drive shaft <NUM>. The distal portion of the optical fiber <NUM> is fixed at a position displaced in the transmission direction D2 of the measurement light ML transmitted from the optical transmitter and receiver 145b with respect to the rotation axis Y of the drive shaft <NUM>. As a result, a space (electric signal cable insertion portion <NUM>) where the electric signal cable <NUM> is disposed at a position opposite to the transmission direction D2 of the measurement light ML with respect to the optical fiber <NUM> can be secured.

The electric signal cable insertion portion <NUM> is provided with a hole portion 222a that is continuous with the groove portion 221a and provided at a position opposite to the transmission direction D2 of the measurement light ML. The hole portion 222a is formed by hollowing out the positioning member <NUM> in a substantially semicircular shape. In the hole portion 222a, two signal lines 142a and 142b are respectively disposed on both sides in a direction (left and right direction in the drawing) orthogonal to the transmission direction D2 of the measurement light ML.

The recess <NUM> is provided in a certain region of the outer surface of the positioning member <NUM>, which is located downstream in the direction D2 of transmission of the measurement light ML. In addition, as illustrated in <FIG>, the housing <NUM> is provided with a notch 146b (corresponding to a "penetration portion") that penetrates a portion on the proximal end of the opening portion 146a (portion for accommodating the positioning member <NUM>) in the thickness direction. As illustrated in <FIG>, the recess <NUM> provided in the positioning member <NUM> and the notch 146b provided in the housing <NUM> are provided at positions that overlap in the radial direction. In addition, a width L2 of the notch 146b (length along the circumferential direction of the housing <NUM>) is longer than a width L3 of the recess <NUM> (maximum length along the circumferential direction of the positioning member <NUM>). Therefore, for example, when the image diagnosis catheter <NUM> is assembled (manufactured), a jig such as a needle or tweezers is inserted from the notch 146b and hooked into the recess <NUM>, the positioning member <NUM> is rotated with respect to the housing <NUM>, and the position in the circumferential direction of the positioning member <NUM> with respect to the housing <NUM> is finely adjusted so that the ultrasound SW intersects with the measurement light ML. Thereafter, the positioning member <NUM> can be fixed to the housing <NUM>. Note that a method of fixing the positioning member <NUM> to the housing <NUM> is not particularly limited, and for example, the positioning member <NUM> can be bonded by an adhesive. In this case, for example, the positioning member <NUM> is rotated while injecting the adhesive from the notch 146b and the adhesive is spread over the peripheral surface of the positioning member <NUM>. Therefore the positioning member <NUM> can be fixed to the housing <NUM>.

It is preferable that the positioning member <NUM> is made of a material having a rigidity that does not deform when the optical fiber <NUM> is pressed. By forming the positioning member <NUM> with such a material, for example, compared with a case where the optical fiber <NUM> is directly fixed to the housing <NUM> with an adhesive, the relative position of the optical transmitter and receiver 145b with respect to the ultrasound transmitter and receiver 145a can be easily determined, when the image diagnosis catheter <NUM> is assembled (manufactured).

In addition, it is preferable that the positioning member <NUM> includes a material having a contrast property (X-ray opaque material) under X-ray fluoroscopy. When the positioning member <NUM> includes such a material, the operator can easily grasp the positions of the positioning member <NUM> and the optical transmitter and receiver 145b provided at the distal end thereof under X-ray fluoroscopy. In particular, in the present embodiment, since the positioning member <NUM> is provided with the groove portion 221a and the hole portion 222a, the thickness of the positioning member <NUM> varies depending on the position in the circumferential direction. For example, as illustrated in <FIG>, in a case where X-rays are irradiated from the lower side to the upper side as indicated by the arrow X in the state where the groove portion 221a is disposed on the upper side, since the X-rays pass through both the groove portion 221a and the hole portion 222a, the thickness of the positioning member <NUM> in the portion through which X-rays pass is thin, and the positioning member <NUM> is displayed relatively thinly under X-ray fluoroscopy. At the position where the positioning member <NUM> is rotated with respect to <FIG> (position illustrated in <FIG>), since the X-rays pass only through the hole portion 222a, the thickness of the positioning member <NUM> in the portion through which X-rays pass is relatively thick, and the positioning member <NUM> is displayed relatively dark under X-ray fluoroscopy. As aforementioned, when the operator rotates the drive shaft <NUM> under X-ray fluoroscopy, the positioning member <NUM> also rotates in conjunction with the rotation, and the region where the positioning member <NUM> is provided changes in shade in conjunction with the rotation. Therefore, the operator can more easily grasp the position of the positioning member <NUM> under X-ray fluoroscopy.

Note that, for example, Pt, Au, a Pt-Ir alloy, or the like can be used as a material having a rigidity that does not deform when the optical fiber <NUM> is pressed and having a contrast property under X-ray fluoroscopy.

Next, an example of use in a case where the image diagnosis catheter <NUM> is inserted into a blood vessel <NUM> (biological lumen) will be described.

First, the user connects the injection device S for injecting the priming solution to the port <NUM> with the hub <NUM> pulled to the most proximal end (refer to <FIG>), and pushes a plunger of the first syringe S4 to inject the priming solution into the lumen 110a of the sheath <NUM>. Note that, in a case where the amount of the priming solution injected by the first syringe S4 is insufficient, the priming solution is injected into the lumen 110a of the sheath <NUM> by pushing a plunger of the second syringe S5.

When the priming solution is injected into the lumen 110a, the priming solution is discharged to the outside of the sheath <NUM> through the communication passage 117a and the communication hole <NUM> illustrated in <FIG>, and a gas such as air can be discharged from the inside of the sheath <NUM> to the outside together with the priming solution (priming processing).

After the priming processing, the user connects the external device <NUM> to the connector portion <NUM> of the image diagnosis catheter <NUM> as illustrated in <FIG>. The user pushes the hub <NUM> until the hub <NUM> attaches the proximal end of the unit connector <NUM> (refer to <FIG>), and moves the signal transmitter and receiver <NUM> to the distal end side.

Next, the user creates a port on the wrist or thigh using an introducer kit. Next, a first guide wire (not illustrated) is inserted through the port to the vicinity of a coronary artery entrance of the heart. Next, a guiding catheter <NUM> is introduced to the coronary artery entrance through the first guide wire. Next, the first guide wire is removed, and a second guide wire W is inserted into a lesion area through the guiding catheter <NUM>. Next, the image diagnosis catheter <NUM> is inserted into the lesion area along the second guide wire W.

Next, as illustrated in <FIG>, the image diagnosis catheter <NUM> is advanced along the lumen 800a and protruded from a distal opening portion of the guiding catheter <NUM>. Thereafter, while the second guide wire W is inserted through the guide wire lumen 114a, the image diagnosis catheter <NUM> is further pushed along the second guide wire W to be inserted into a target position in the blood vessel <NUM>. Note that, as the guiding catheter <NUM>, a known guiding catheter provided with a port (not illustrated) to which a syringe (not illustrated) can be connected at a proximal portion can be used.

Next, the blood in the blood vessel <NUM> is temporarily replaced with a flush solution such as a contrast agent. Similarly to the priming processing aforementioned, the syringe containing the flush solution is connected to the port of the guiding catheter <NUM>, and the plunger of the syringe is pushed to inject the flush solution into the lumen 800a of the guiding catheter <NUM>. As illustrated by an arrow C in <FIG>, the flush solution passes through the lumen 800a of the guiding catheter <NUM> and is introduced into the blood vessel <NUM> through the distal opening portion. The blood around the distal portion of the sheath <NUM> is washed away by the introduced flush solution, and the flush solution is filled around the distal portion of the sheath <NUM>. Note that, in the mode of acquiring a tomographic image only by IVUS, the above-described step of replacing with the flash solution can be omitted.

When obtaining a tomographic image at a target position in the blood vessel <NUM>, the signal transmitter and receiver <NUM> moves to the proximal end side while rotating with the drive shaft <NUM> (pull-back operation). Simultaneously with the pull-back operation, as illustrated in <FIG>, the ultrasound transmitter and receiver 145a transmits the ultrasound SW toward a blood vessel wall 900b and receives the ultrasound reflected by the blood vessel wall 900b. In addition, the optical transmitter and receiver 145b simultaneously transmits the measurement light ML toward the blood vessel wall 900b and receives the reflected light reflected by the blood vessel wall 900b. Note that, as aforementioned, since the ultrasound SW transmitted from the ultrasound transmitter and receiver 145a intersects with the measurement light ML transmitted from the optical transmitter and receiver 145b, a region to be inspected by the ultrasound in the living body and a regions to be inspected with the light can be overlapped.

Note that the rotation and movement operation of the drive shaft <NUM> is controlled by the control apparatus <NUM>. The connector portion <NUM> provided in the hub <NUM> is rotated while being connected to the external device <NUM>, and the drive shaft <NUM> is rotated in conjunction with the rotation.

In addition, the signal transmitter and receiver <NUM> transmits the ultrasound and light into the body based on the signal sent from the control apparatus <NUM>. A signal corresponding to the reflected wave and the reflected light received by the signal transmitter and receiver <NUM> is sent to the control apparatus <NUM> via the drive shaft <NUM> and the external device <NUM>. The control apparatus <NUM> generates a tomographic image of the body-cavity based on the signal sent from the signal transmitter and receiver <NUM> and displays the generated image on the monitor <NUM>.

Hereinbefore, the image diagnosis catheter <NUM> according to the present embodiment includes the rotatable drive shaft <NUM>, the sheath <NUM> into which the drive shaft <NUM> is inserted, the housing <NUM> provided at the distal end of the drive shaft <NUM> and accommodating the ultrasound transmitter and receiver 145a and the optical transmitter and receiver 145b, and the positioning member <NUM> fixed to the housing <NUM> and fixes the relative position of the optical transmitter and receiver 145b with respect to the ultrasound transmitter and receiver 145a.

As aforementioned, the relative position of the optical transmitter and receiver 145b with respect to the ultrasound transmitter and receiver 145a is fixed. Therefore, the transmission direction of the measurement light ML with respect to the transmission direction of the ultrasound SW can be kept in a fixed direction. As a result, for example, at the time of manufacture (assemble), the relative position of the measurement light ML with respect to the ultrasound SW of each image diagnosis catheter <NUM> can be kept within a desired tolerance.

In addition, the positioning member <NUM> fixes the relative position of the optical transmitter and receiver 145b with respect to the ultrasound transmitter and receiver 145a so that the ultrasound SW transmitted from the ultrasound transmitter and receiver 145a intersects with the measurement light ML transmitted from the optical transmitter and receiver 145b. Therefore, the ultrasound can be made to intersect with light at a fixed position. In addition, the inspection region of the ultrasound SW and the inspection region of the measurement light ML in the living body can be overlapped.

In addition, the drive shaft <NUM> is provided with the optical fiber <NUM> optically connected to the optical transmitter and receiver 145b, and the positioning member <NUM> is provided with the optical fiber fixing portion <NUM> that fixes the optical fiber <NUM>. Therefore, by fixing the optical fiber <NUM>, the direction where the optical transmitter and receiver 145b transmits the measurement light ML can be easily adjusted.

In addition, the drive shaft <NUM> is provided with the electric signal cable <NUM> electrically connected to the ultrasound transmitter and receiver 145a, and in the positioning member <NUM>, the electric signal cable <NUM> is disposed at a position opposite to the transmission direction D2 of the measurement light ML transmitted from the optical transmitter and receiver 145b with respect to the optical fiber <NUM>. Therefore, the electric signal cable <NUM> can be electrically connected to the ultrasound transmitter and receiver 145a accommodated in the housing <NUM> without interfering with transmission and reception of light from the optical transmitter and receiver 145b.

In addition, the optical fiber fixing portion <NUM> fixes the optical fiber <NUM> at a position displaced in the transmission direction D2 of the measurement light ML transmitted from the optical transmitter and receiver 145b with respect to the rotation axis Y of the drive shaft <NUM>. Therefore, in the limited internal space of the housing <NUM>, the positioning member <NUM> can dispose the optical fiber <NUM> and the electric signal cable <NUM>.

In addition, the optical fiber fixing portion <NUM> is provided with the concave groove portion 221a into which the optical fiber <NUM> can be fitted. Therefore, the position of the optical fiber <NUM> can be easily determined by fitting the optical fiber <NUM> into the groove portion 221a.

In addition, the positioning member <NUM> is provided with the recess <NUM> on the outer surface, and the housing <NUM> is provided with the notch 146b penetrating the housing <NUM> in the thickness direction at a position overlapping the recess <NUM> in the radial direction. Therefore, a jig such as a needle or tweezers is inserted into the notch 146b and hooked into the recess <NUM>, so that the positioning member <NUM> can be fixed to the housing <NUM>, after the position of the positioning member <NUM> accommodated in the housing <NUM> is finely adjusted.

The positioning member <NUM> includes a material having a contrast property under X-ray fluoroscopy. Therefore, the operator can easily grasp the positions of the positioning member <NUM> and the optical transmitter and receiver 145b under X-ray fluoroscopy.

The ultrasound transmitter and receiver 145a is fixed to the housing <NUM>. Therefore, the relative position of the optical transmitter and receiver 145b with respect to the ultrasound transmitter and receiver 145a can be easily determined.

Next, a positioning member <NUM> according to Modification <NUM> will be described with reference to <FIG>.

The positioning member <NUM> according to the Modification <NUM> is different from the positioning member <NUM> according to the above-described embodiment in that the positioning member <NUM> is configured by combining two members. Note that, the same components as those of the image diagnosis catheter <NUM> according to the above embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

The positioning member <NUM> is provided with a cylindrical first member <NUM> and a second member <NUM> accommodated in the first member <NUM>.

The first member <NUM> is accommodated in the housing <NUM>.

The second member <NUM> has a shape in which an opening portion 322a is provided on the upper side of a cylindrical pipe. The opening portion 322a is formed over the entire length in the axial direction of the second member <NUM>. The optical fiber <NUM> is disposed so as to attach end portions 322b and 322c (corresponding to "first attachment portion" and "second attachment portion") on both sides across the opening portion 322a. In addition, the electric signal cable <NUM> is disposed so as to be inserted under the optical fiber <NUM> (side opposite to the transmission direction D2 of the measurement light ML).

As aforementioned, the optical fiber fixing portion of the positioning member <NUM> according to Modification <NUM> is provided with the first attachment portion 322b that attaches a peripheral surface of the optical fiber <NUM>, and the second attachment portion 322c that is spaced apart from the first attachment portion 322b and capable of interposing the optical fiber <NUM> with the first attachment portion 322b. Therefore, the position of the optical fiber <NUM> can be easily determined by disposing the optical fiber <NUM> between the first attachment portion 322b and the second attachment portion 322c.

The positioning member <NUM> according to Modification <NUM> is different from the positioning member <NUM> according to the above-described embodiment in the position where a recess <NUM> is provided. Note that, the same components as those of the image diagnosis catheter <NUM> according to the above embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

The recess <NUM> is provided in a region on the side opposite to the transmission direction D2 side of the measurement light ML of the outer surface of the positioning member <NUM>. In addition, a through-hole 446b (corresponding to a "penetration portion") is provided on the lower side of the housing <NUM> so as to penetrate a portion accommodating the positioning member <NUM> in the thickness direction. The recess <NUM> provided in the positioning member <NUM> and the through-hole 446b provided in the housing <NUM> are provided at a position overlapping in the radial direction. In addition, a width L4 of the through-hole 446b (length along the circumferential direction of the housing <NUM>) is longer than a width L5 of the recess <NUM> (maximum length along the circumferential direction of the positioning member <NUM>). Therefore, for example, when the image diagnosis catheter <NUM> is assembled (manufactured) , a jig such as a needle or tweezers is inserted from the through-hole 446b and hooked into the recess <NUM>, and the position of the positioning member <NUM> with respect to the housing <NUM> is finely adjusted so that the ultrasound SW intersects with the measurement light ML. Thereafter, the positioning member <NUM> can be fixed to the housing <NUM>.

As aforementioned, the positions in the circumferential direction of the recess provided in the positioning member and the penetration portion provided in the housing are not particularly limited.

The positioning member <NUM> according to Modification <NUM> is different from the positioning member <NUM> according to the above-described embodiment in that the distal portion of the optical fiber <NUM> is fixed at a position where the central axis of the optical fiber <NUM> coincides with the rotation axis Y of the drive shaft <NUM>. Note that, the same components as those of the image diagnosis catheter <NUM> according to the above embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

The positioning member <NUM> is provided with a first member <NUM> accommodated in the housing <NUM> and a second member <NUM> accommodated in the first member <NUM>.

The first member <NUM> has a shape in which an opening portion 521a is provided on the lower side of the cylindrical pipe. An electric signal cable <NUM> is disposed in an opening portion 521a.

The second member <NUM> has a cylindrical outer shape. The second member <NUM> is provided with a through-hole 522a so as to penetrate the center of the shaft. The optical fiber <NUM> is fixed so as to insert the through-hole 522a of the second member <NUM>. Therefore, compared with the case where the optical fiber fixing portion aforementioned is configured to include the groove portion 221a, since the peripheral surface of the optical fiber <NUM> can be covered by the second member <NUM>, the position of the optical fiber <NUM> can be further preferably be determined. Note that, in addition to the inner diameter r2 of the housing <NUM> being required to be relatively small as described in the above embodiment, it is necessary to secure the thickness of the second member <NUM> to some extent in order to maintain the strength of the second member <NUM> in Modification <NUM>. Therefore, the electric signal cable <NUM> is disposed in the opening portion 521a of the first member <NUM>.

Hereinbefore, the image diagnosis catheter according to the present invention has been described through the embodiment and the modification. The present invention is not limited to the configuration described in the embodiment and the modification, and can be appropriately changed based on the description of the scope of aspects.

For example, in the above-described embodiment, the embodiment has been described in which the image diagnosis catheter according to the present invention is applied to an image diagnosis catheter having the functions of the intra vascular ultra sound (IVUS) diagnosis method and the optical coherence tomography (OCT) diagnosis method. The image diagnosis catheter according to the present invention is not particularly limited as long as the image diagnosis catheter uses the ultrasound and light as inspection wave. For example, the present invention may be applied to an image diagnosis catheter having functions of an intra vascular ultra sound (IVUS) diagnosis method and an optical frequency domain imaging (OFDI) method.

In addition, for example, in the above embodiment, the aspect was described which the positioning member fixes the position of the optical transmitter and receiver with respect to the ultrasound transmitter and receiver so that the ultrasound transmitted from the ultrasound transmitter and receiver intersects with light transmitted from the optical transmitter and receiver. The configuration of the positioning member is not particularly limited as long as the relative position of the optical transmitter and receiver with respect to the ultrasound transmitter and receiver can be fixed. For example, the positioning member may be configured to fix the relative position of the optical transmitter and receiver with respect to the ultrasound transmitter and receiver so that the transmission direction of the ultrasound transmitted from the ultrasound transmitter and receiver are parallel to the transmission direction of light transmitted from the optical transmitter and receiver. In a case where the ultrasound is parallel to light, the ultrasound and light are separated by a fixed distance along the axial direction of the drive shaft. Therefore, for example, when a plurality of tomographic images are acquired by using the ultrasound and light as the inspection wave with the pull-back operation, considering that the ultrasound and light are separated by a fixed distance, from a plurality of tomographic images, it is possible to extract a tomographic image obtained by using the ultrasound acquired at the same position in the biological lumen as the inspection wave and a tomographic image acquired by using light as the inspection wave.

In addition, for example, in the above-described embodiment, the optical transmitter and receiver is described as being configured to include a ball lens. The optical transmitter and receiver is not particularly limited, as long as light in the axial direction propagating from the optical fiber is transmitted toward the biological tissue in the biological lumen, and the reflected light reflected by the biological tissue is received and propagated to the optical fiber. For example, the optical transmitter and receiver may be configured to include an optical mirror.

For example, in the above embodiment, the electric signal cable (signal line) has been described as being configured to include two cables. The electric signal cable may be configured to include, for example, a coaxial cable (one cable). In addition, the electric signal cable may be a twisted pair cable in which two cables are wound around the optical fiber.

Claim 1:
An image diagnosis catheter comprising:
a rotatable drive shaft (<NUM>);
a sheath into which the drive shaft (<NUM>) is inserted;
housing (<NUM>) provided at a distal end of the drive shaft (<NUM>)
and accommodating an ultrasound transmitter and receiver (145a) and an optical transmitter and receiver (145b); and
a positioning member (<NUM>, <NUM>, <NUM>, <NUM>) fixed to the housing (<NUM>) and fixing a relative position of the optical transmitter and receiver (145b) with respect to the ultrasound transmitter and receiver (145a),
wherein
the drive shaft (<NUM>) includes an optical fiber (<NUM>) connected to the optical transmitter and receiver (145b), and
being characterized in that the positioning member (<NUM>, <NUM>, <NUM>, <NUM>) includes an optical fiber (<NUM>) fixing portion that fixes the optical fiber (<NUM>), and
the optical fiber (<NUM>) fixing portion fixes the optical fiber (<NUM>) at a position displaced in a transmission direction (D2) of light transmitted from the optical transmitter and
receiver (145b) with respect to a rotation axis (Y) of the drive shaft (<NUM>).