JP2012205661A - Catheter assembly - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a catheter assembly capable of preventing or suppressing vibrations in the radial direction inside a catheter body of a transmission/reception part when a shaft is rotated.SOLUTION: The catheter assembly 1 includes: a catheter body 21 to be inserted into a living body lumen; a drive shaft 4 inserted into the catheter body 21 and rotated around the axis; an imaging means 5 provided with a transmission/reception part 52 fixed to the part on the distal end side of the drive shaft 4, for fetching signals for forming an image inside the living body lumen while being rotated together with the drive shaft 4; and a distal end member 7 supported on the more distal end side than the transmission/reception part 52 of the drive shaft 4. The distal end member 7 forms a columnar shape as a whole, and the outer diameter φdof an intermediate part 73 between the distal end part 71 and the proximal end part 72 is larger than any of the outer diameter of the distal end part 71, the outer diameter of the proximal end part 72 and the outer diameter φdof the drive shaft 4.

Description

  The present invention relates to a catheter assembly.

  Conventionally, in order to diagnose arteriosclerosis, preoperative diagnosis at the time of endovascular treatment with a high-function catheter such as a balloon catheter or a stent, or to confirm the result after surgery, an optical coherence tomography diagnostic apparatus (OCT) or ( For example, see Patent Document 1), an optical coherence tomographic image diagnosis apparatus (SS-OCT) using wavelength sweep, which is an improved version thereof (hereinafter referred to as an optical coherence tomographic image diagnosis apparatus ( OCT) and optical coherence tomographic imaging apparatus (SS-OCT) using wavelength sweep are collectively referred to as “optical imaging apparatus”).

  In the optical diagnostic imaging apparatus, an optical lens or an optical mirror (hereinafter referred to as a transmission / reception unit) is attached to the tip of an optical fiber cable, and an imaging core having a coiled drive shaft inserted through the optical fiber cable is inserted. The catheter is inserted into the blood vessel, and while rotating the imaging core, the measuring light is emitted from the transmitting / receiving unit at the tip into the blood vessel, and the reflected light from the living tissue is received to perform radial scanning in the blood vessel. Then, after the interference light is generated by causing the received reflected light and the reference light to interfere with each other, a cross-sectional image of the blood vessel is drawn based on the interference light.

  Further, when acquiring a tomographic image, a liquid such as a physiological saline or a contrast agent is formed in a lumen, that is, in a gap formed between the inner peripheral surface of the catheter body and the outer peripheral surface of the imaging core. And do the work. This gap is secured to a certain extent to such an extent that the liquid can be easily and quickly filled. In addition, when the shaft moves to the base end portion at a bent portion or the like, the lumen becomes flat. Therefore, when the shaft is returned to the distal end direction, the housing that protects the optical lens is caught by the lumen, and the shaft cannot be returned to the distal end. In order to avoid this, a large gap is secured.

  However, in the catheter described above, when the gap is formed, the transmission / reception unit vibrates in the radial direction of the catheter body together with the shaft when rotated with the shaft. It rotates while being eccentric with respect to the central axis. In the optical coherence tomography diagnosis apparatus, the length of the optical fiber 56 built in the catheter is important, and adjustment with a dedicated apparatus connected to the catheter is necessary to correct individual differences. Since this adjustment uses the outer and inner peripheral surfaces of the lumen, if it is decentered, the optimal adjustment cannot be performed and the obtained image is incorrect (correct blood vessel diameter cannot be measured). was there.

JP 2007-268133 A

  The objective of this invention is providing the catheter assembly which can prevent or suppress the vibration to the radial direction in the catheter main body of a transmission / reception part, when a shaft rotates.

Such an object is achieved by the present inventions (1) to (16) below.
(1) a catheter body that is inserted into a living body lumen, has flexibility, and forms a tube;
A shaft that is inserted into the catheter body and used in an elongated shape and rotates about its axis;
An imaging unit having a transmission / reception unit that is fixed to a distal end portion of the shaft, rotates with the shaft, and faces the living body lumen to capture a signal for forming an image in the living body lumen;
A tip member supported on the tip side of the transmission / reception part of the shaft,
The distal end member has a columnar shape as a whole, and an outer diameter of an intermediate portion between the distal end portion and the proximal end portion is an outer diameter of the distal end portion, an outer diameter of the proximal end portion, and an outer diameter of the shaft. A catheter assembly that is larger than any outer diameter.

  (2) The catheter assembly according to (1), wherein the tip member has a function of suppressing or preventing vibration of the catheter body in the radial direction when the shaft rotates.

  (3) The catheter assembly according to (1) or (2), wherein the intermediate portion of the distal end member is in point contact or line contact with the inner peripheral surface of the catheter body.

  (4) The catheter assembly according to any one of (1) to (3), wherein the tip member has elasticity.

  (5) The catheter assembly according to any one of (1) to (4), wherein the distal end member is a wire wound in a spiral shape.

  (6) The catheter assembly according to (5), wherein the wire is wound in the same direction as the rotation direction of the shaft.

  (7) The catheter assembly according to (5) or (6), wherein the adjacent wires are separated from each other.

  (8) Any one of the above (1) to (4), wherein the tip member includes at least three pairs of links linked to each other so as to be rotatable around the central axis of the shaft at equal angular intervals. A catheter assembly according to claim 1.

  (9) The catheter assembly according to (8), wherein an angle formed by the pair of links is variable according to a size of an inner diameter of the catheter body.

  (10) The catheter assembly according to any one of (4) to (9), wherein the tip member is freely expandable / reducing.

  (11) The catheter assembly according to any one of (1) to (10), wherein the distal end member is provided with a communication portion that communicates the distal end side and the proximal end side.

  (12) The catheter assembly according to any one of (1) to (11), further including a rotational force relaxation means for relaxing transmission of the rotational force to the distal end member when the shaft rotates.

  (13) The catheter assembly according to any one of (1) to (12), wherein the catheter body has an opening opened at a distal end thereof.

  (14) The catheter assembly according to any one of (1) to (13), wherein a tubular guide wire insertion portion through which a guide wire can be inserted is installed on an outer peripheral portion of the distal end of the catheter body.

  (15) The catheter assembly according to any one of (1) to (14), wherein the catheter body is filled with a liquid while the shaft is inserted.

(16) The transmission / reception unit is an optical lens and an optical mirror that perform light projection and reception of near infrared light,
The catheter assembly according to any one of (1) to (15), wherein the imaging unit is configured to form the image based on information obtained from the near-infrared light.

  According to the present invention, the intermediate portion of the tip member can be as close as possible to the inner peripheral surface of the catheter body. When the shaft rotates in this state, the shaft can rotate while being in line contact or point contact with the inner peripheral surface of the catheter body at the intermediate portion. Thereby, the vibration to the radial direction of the catheter main body by the front-end | tip side of a shaft in the catheter main body, especially a transmission / reception part can be suppressed or prevented. Therefore, since the distance between the transmitting / receiving unit and the inner peripheral surface of the catheter body is kept substantially constant, optimal adjustment is possible.

It is a partial longitudinal cross-sectional side view which shows 1st Embodiment of the catheter assembly of this invention. It is a partial longitudinal cross-sectional side view which shows 1st Embodiment of the catheter assembly of this invention. FIG. 2 is an enlarged partial longitudinal sectional view of a region [A] surrounded by a one-dot chain line in FIG. 1. It is a fragmentary longitudinal cross-section which shows 2nd Embodiment of the catheter assembly of this invention. It is a fragmentary longitudinal cross-section which shows 3rd Embodiment of the catheter assembly of this invention. It is a fragmentary longitudinal cross-section which shows 4th Embodiment of the catheter assembly of this invention.

  Hereinafter, a catheter assembly of the present invention will be described in detail based on a preferred embodiment shown in the accompanying drawings.

<First Embodiment>
1 and FIG. 2 are partial longitudinal sectional side views showing a first embodiment of the catheter assembly of the present invention, respectively. FIG. 3 is an enlarged partial longitudinal section of a region [A] surrounded by a dashed line in FIG. FIG. In the following, for convenience of explanation, the right side in FIGS. 1 and 3 (the same applies to FIGS. 4 to 6) is referred to as “base end”, and the left side is referred to as “tip”.

  A catheter assembly 1 shown in FIG. 1 includes a catheter 2 and an imaging core 3 inserted into the catheter 2. The catheter assembly 1 is used by being inserted into a living body lumen (hereinafter, “blood vessel” is representatively treated) in an assembled state in which the catheter 2 and the imaging core 3 are assembled. The tomographic image is acquired.

  The catheter assembly 1 is used by being connected to an external unit 6. The external unit 6 includes a scanner device 61 incorporating an external drive source such as a motor, an axial movement device 62 that holds the scanner device 61 and moves it horizontally (axial direction) by the motor, and the like, and the scanner device 61 and the axial direction. It comprises a control unit 63 having a function of controlling the operation of the moving device 62 and a display unit 64 that displays an image of the blood vessel wall obtained by the catheter assembly 1.

  Before describing the configuration of each part of the catheter assembly 1, the external unit 6 will be described.

  The proximal end portion of the catheter assembly 1 is connected to the scanner device 61. The scanner device 61 can rotate the imaging core 3 about its axis and can be moved along the axial direction of the catheter assembly 1 by the axial direction moving device 62. Thereby, the transmission / reception part 52 of the imaging core 3 can be scanned. Further, a tomographic image of a blood vessel can be formed by a scanner built in the scanner device 61 based on information obtained from the reflected wave of the transmission / reception unit 52 of the imaging core 3. Thereby, the cross-sectional image in the blood vessel which is an ultrasonic image is obtained in arbitrary positions with respect to the blood vessel over the perimeter of the circumferential direction.

The control unit 63 is a personal computer with a built-in CPU (Central Processing Unit), for example.
The display unit 64 is a liquid crystal display device, for example.

Next, the catheter assembly 1 will be described.
As described above, the catheter assembly 1 includes the catheter 2 and the imaging core 3.

  The catheter 2 includes a catheter main body 21 having a tube shape and a connector portion 22 fixed to a proximal end portion of the catheter main body 21.

  As shown in FIG. 3, the catheter body 21 has a lumen 211 formed along the longitudinal direction thereof. The imaging core 3 is inserted into the lumen 211. In this inserted state, the lumen 211 is filled with the liquid Q. The liquid Q is not particularly limited, and examples thereof include physiological saline and a contrast medium.

  The lumen 211 has an opening 212 that opens at the distal end of the catheter body 21.

  A guide wire insertion portion 23 into which the guide wire 200 can be inserted is installed on the outer peripheral portion of the distal end of the catheter body 21. The guide wire insertion portion 23 is configured by a tubular member having both ends opened. The catheter 2 is inserted into the blood vessel in a state where the guide wire 200 is inserted through the guide wire insertion portion 23, and the so-called “rapid exchange type (short monorail type) that allows the guide wire 200 to be quickly inserted and removed. ) "Catheter.

  In the configuration shown in FIG. 1, the guide wire insertion portion 23 is disposed so as to be inclined with respect to the central axis of the catheter body 21, but is not limited thereto, and is disposed, for example, in parallel with the central axis of the catheter body 21. It may be.

  A coil 24 is embedded in the middle of the guide wire insertion portion 23 in the longitudinal direction. The coil 24 functions as a contrast marker for visually recognizing the position of the distal end portion of the catheter 2 under fluoroscopy. The coil 24 is made of a metal material having radiopacity, such as platinum.

  The catheter body 21 and the guide wire insertion part 23 are each made of a flexible material, and the material is not particularly limited. For example, the styrenic, polyolefinic, polyurethane, polyester, polyamide, Various thermoplastic elastomers such as polyimide, polybutadiene, trans polyisoprene, fluororubber, chlorinated polyethylene, etc. are listed, and one or a combination of two or more of these (polymer alloy, polymer blend) , Laminates, etc.) can be used.

  The catheter body 21 and the guide wire insertion portion 23 may each be a single-layer tube wall, or may be a laminate in which a plurality of layers are laminated.

  The connector portion 22 fixed to the proximal end portion of the catheter main body 21 is constituted by a hard tube. The connector unit 22 is connected to the scanner device 61 of the external unit 6.

  The method for fixing the connector portion 22 to the catheter body 21 is not particularly limited. For example, a method using adhesion (adhesion with an adhesive or a solvent), fusion (thermal fusion, high-frequency fusion, ultrasonic fusion), or the like. ) And the like.

  In the middle of the connector portion 22 in the longitudinal direction, a liquid injection port 221 branched from the portion is formed to project. For example, the liquid Q can be injected from the liquid injection port 221 using a syringe. Then, the injected liquid Q is filled in the lumen 211 of the catheter body 21.

  A rotation support part 222 that rotatably supports the imaging core 3 is provided at the base end part of the connector part 22.

  In addition, a seal member 25 is installed at the proximal end portion of the connector portion 22 on the distal end side with respect to the rotation support portion 222. The seal member 25 is configured by an elastic body having a ring shape. Thereby, it is possible to prevent the seal member 25 from generating a gap between the inner peripheral portion of the connector portion 22 and the outer peripheral portion of the imaging core 3, that is, the liquid tightness is maintained. Leakage toward the proximal direction can be prevented.

  On the distal end side of the connector portion 22, there are a unit connector 32 connected via an inner tube 312 and a relay connector 33 connected to the unit connector 32 via an outer tube 331 and connected to the catheter body 21.

  The connector part 22 holds the drive shaft 4 and the inner tube 312. When the inner tube 312 is pushed into or pulled out of the unit connector 32 and the outer tube 331, the drive shaft 4 is slid in the catheter body 21 in the axial direction in conjunction with it.

  When the inner tube 312 is pushed in the most, as shown in FIG. 1, the inner tube 312 reaches the end on the catheter body 21 side near the end of the outer tube 331 on the catheter body 21 side, that is, near the relay connector 33. . In this state, the transmission / reception unit 52 is located near the distal end of the catheter body 21 of the catheter 2.

  When the inner tube 312 is pulled out most, as shown in FIG. 2, the stopper 313 formed at the tip of the inner tube 312 is caught by the inner wall of the unit connector 32, and the portions other than the vicinity of the caught tip are exposed. In this state, the transmitter / receiver 52 is pulled back with the catheter 2 remaining. As the transmitter / receiver 52 moves while rotating, tomographic images of blood vessels and vessels can be created.

  The constituent material of the connector portion 22 is not particularly limited. For example, polyvinyl chloride, polyethylene, polypropylene, cyclic polyolefin, polystyrene, poly- (4-methylpentene-1), polycarbonate, acrylic resin, acrylonitrile-butadiene- Various resins such as styrene copolymers, polyesters such as polyethylene terephthalate, polyethylene naphthalate, butadiene-styrene copolymers, polyamides (for example, nylon 6, nylon 6,6, nylon 6,10, nylon 12) can be used. .

  In the configuration shown in FIG. 1, the connector portion 22 is formed by connecting three tubular bodies along the longitudinal direction. However, the connector portion 22 is not limited to this, and may be configured by, for example, one tubular body. .

  As shown in FIG. 3, the imaging core 3 is inserted into the catheter 2. The imaging core 3 in the inserted state rotates around the central axis by the operation of the scanner device 61. In addition, although the rotation speed of the imaging core 3 is not specifically limited, For example, it is preferable that it is 500-10000 rpm, and it is more preferable that it is 1800-9600 rpm.

  The imaging core 3 includes a long drive shaft 4 as a main body, a housing 51 fixed to the distal end portion of the drive shaft 4, a transmission / reception unit 52 accommodated in the housing 51, and a proximal end of the drive shaft 4. The connector part 53 fixed to the part and the tip member 7 are provided. In the imaging core 3, the housing 51, the transmission / reception unit 52, and the connector unit 53 constitute an imaging unit 5 that captures an image of the blood vessel wall.

  The drive shaft 4 has a torque transmission property capable of reliably transmitting the rotational force generated by the operation of the scanner device 61 to the transmission / reception unit 52. The drive shaft 4 is formed by, for example, winding a metal wire such as stainless steel in a coil shape in a close winding (see FIG. 3). In addition, this metal wire may be wound by multiple.

The outer diameter φd ₁ of the drive shaft 4 is smaller than the inner diameter φd ₂ of the catheter body 21. As a result, a gap 213 is formed between the outer peripheral surface 41 of the drive shaft 4 and the inner peripheral surface 214 of the catheter body 21. The liquid Q injected from the liquid injection port 221 of the catheter 2 flows down through the gap 213 and is discharged from the opening 212.

Note that the size of the gap 213, that is, (inner diameter φd ₂ −outer diameter φd ₁ ) depends on the type of the liquid Q, but is such that the liquid Q can flow down quickly and reliably. It is preferably 0.05 to 0.25 mm.

  Next, the configuration of the distal end portion of the catheter 2 will be described with reference to FIG. As shown in FIG. 3, a housing 51 in which a transmitter / receiver 52 for transmitting measurement light and receiving reflected light is arranged inside the lumen of the catheter body 21 and a rotational driving force for rotating the housing 51 are transmitted. An imaging core 3 including a drive shaft 4 is inserted through substantially the entire length to form a catheter 2.

The transmission / reception unit 52 transmits measurement light toward the tissue in the living body lumen and receives reflected light from the tissue in the living body lumen.
The drive shaft 4 is formed in a coil shape, and an optical fiber 56 is disposed therein.

  The housing 51 has a shape having a notch 511 in a part of a short cylindrical metal pipe, and is formed by cutting out from a metal lump, MIM (metal powder injection molding) or the like. The housing 51 has a transmission / reception unit 52 inside, and the base end side is connected to the drive shaft 4.

  The drive shaft 4 is capable of rotating and axially moving the transmitting / receiving unit 52 with respect to the catheter body, is flexible, and has a characteristic capable of transmitting rotation well, for example, a multiplex made of a metal wire such as stainless steel. It is comprised by the multilayer close_contact | adherence coil.

  As shown in FIG. 1, a side-illuminated ball lens (transmission / reception unit 52) is fixed by a marker 54 in the housing 51, and a clad portion and a core portion are formed in the drive shaft 4. An optical fiber 56 is disposed. Note that the measurement light transmitted from the transmission / reception unit 52 passes through the catheter body 21 and is irradiated onto the living tissue in the blood vessel.

  An optical fiber 56 is inserted through the drive shaft 4 from the transmission / reception unit 52 and optically connected to the connector unit 53.

  The connector unit 53 is connected to the scanner device 61 and can directly receive the rotational force from the scanner device 61. The connector portion 53 is composed of an optical connector. Accordingly, the connector unit 53 can also be optically connected to the scanner device 61, and a signal from the transmission / reception unit 52 is transmitted to the display unit 64 via the scanner device 61, whereby an image of the blood vessel wall is displayed on the display unit. 64.

The tip member 7 is a member having a cylindrical shape as a whole (the overall shape of the outer shape). The outer diameter φd ₃ of the intermediate portion 73 between the distal end portion 71 and the proximal end portion 72 of the distal end member 7 is larger than the outer diameter (average) of the distal end portion 71, and the outer diameter (average) of the proximal end portion 72. Bigger than). Further, the outer diameter φd ₃ is larger than the outer diameter φd ₁ of the drive shaft 4. As a result, the outer diameter φd ₃ of the intermediate portion 73 is the same as or slightly smaller than the inner diameter φd ₂ of the catheter body 21.

  In addition, the outer peripheral portion of the distal end portion 71 has a tapered shape whose outer diameter gradually decreases in the distal direction, and the outer peripheral portion of the proximal end portion 72 also has a tapered shape in which the outer diameter gradually decreases in the proximal direction. Eggplant.

  The tip member 7 is formed with a groove along the longitudinal direction, particularly near the intermediate portion 73. This groove serves as a communicating portion that communicates the distal end side and the proximal end side of the distal end member 7, and functions as a bypass that passes when the liquid Q exceeds the intermediate portion 73.

  The imaging core 3 including the tip member 7 having such a shape is as close as possible to the inner peripheral surface 214 of the catheter main body 21 at the intermediate portion 73 between the catheter main body 21 and the other portions as described above. The gap 213 is maintained so that the liquid Q can easily pass therethrough. When the imaging core 3 rotates in this state, the imaging core 3 rotates while being in line contact with the inner peripheral surface 214 of the catheter body at the intermediate portion 73. Thereby, the vibration to the radial direction of the catheter main body 21 in the part at the front end side of the imaging core 3 (drive shaft 4) can be suppressed or prevented. As a result, the position of the transmitting / receiving unit 52 is regulated so as to be concentric with the catheter body 21 as much as possible, that is, on the center line of the catheter body 21. Thus, the tip member 7 has a centering function. With this function, the distance between the rotating transmission / reception unit 52 and the inner peripheral surface 214 of the catheter body 21 is kept substantially constant.

  As described above, in optical coherence tomography diagnosis, the distance between the transmitter / receiver 52 and the catheter body 21 being kept substantially constant is extremely effective in adjusting individual differences.

  The tip member 7 is made of a material having elasticity, and the material is not particularly limited. For example, natural rubber, isoprene rubber, butadiene rubber, styrene-butadiene rubber, nitrile rubber, chloroprene rubber, butyl rubber, acrylic rubber, Various rubber materials (especially those vulcanized) such as ethylene-propylene rubber, hydrin rubber, urethane rubber, silicone rubber, fluoro rubber, styrene, polyolefin, polyvinyl chloride, polyurethane, polyester, polyamide And various thermoplastic elastomers such as polybutadiene, trans polyisoprene, fluororubber, and chlorinated polyethylene, and one or more of these can be used in combination. By being comprised with such an elastic material, the front-end | tip member 7 can be elastically deformed, for example, it can prevent damaging the internal peripheral surface 214 of the catheter main body 21 when it rotates.

Second Embodiment
FIG. 4 is a partial longitudinal sectional view showing a second embodiment of the catheter assembly of the present invention.

Hereinafter, the second embodiment of the catheter assembly of the present invention will be described with reference to this figure, but the description will focus on the differences from the above-described embodiment, and the description of the same matters will be omitted.
This embodiment is the same as the first embodiment except that the configuration of the tip member is different.

  In the catheter assembly 1 shown in FIG. 4, the distal end member 7 </ b> A is composed of a metal wire 75 having elasticity such as stainless steel. The distal end member 7A is obtained by spirally winding the wire 75, and has a spindle shape as a whole, that is, the intermediate portion 73 has the largest outer diameter.

  Further, in the tip member 7A, adjacent wire rods 75 are separated from each other. As a result, a communicating portion 751 that connects the distal end side and the proximal end side is formed in the distal end member 7A. The communication portion 751 functions as a bypass that passes when the liquid Q passes over the tip member 7A.

  The tip member 7A having such a configuration has a different shape between the natural state shown in FIG. 4A where no external force is applied and the rotation state shown in FIG. 4B where the imaging core 3 is rotated. The distal end member 7A is slightly expanded in diameter compared to the natural state due to the centrifugal force acting in the rotating state. At this time, the imaging core 3 contacts the inner peripheral surface 214 of the catheter body 21 at the intermediate portion 73 of the distal end member 7A. This can suppress or prevent vibrations in the radial direction of the catheter body 21 at the distal end side of the imaging core 3, particularly at the transmission / reception unit 52, and thus the inner periphery of the transmission / reception unit 52 and the catheter body 21. The distance from the surface 214 can be kept substantially constant. Thereby, appropriate adjustment is possible. Further, when the rotation of the imaging core 3 stops, the distal end member 7A becomes in a natural state, and the centrifugal force is eliminated and the diameter is reduced.

  The tip member 7A has elasticity. Thereby, the tip member 7A can be curved and deformed in the middle of the longitudinal direction. For example, when the catheter body 21 passes through a curved portion of the blood vessel, the catheter body 21 also bends and deforms according to the curved shape of the blood vessel. Since the distal end member 7A can be curved and deformed, when the distal end member 7A passes through the curved and deformed portion of the catheter body 21, the passage is easily and smoothly performed.

  It is preferable that the wire rod 75 constituting the distal end member 7A is wound in the same direction as the rotation direction of the imaging core 3. Thereby, the diameter of the tip member 7A increases while the imaging core 3 is rotating, and when the imaging core 3 moves forward while rotating, the tip member 7A assists the advancement (having an effect like a screw). be able to.

  Moreover, the cross-sectional shape of the wire 75 is not particularly limited, but is preferably circular or elliptical. Thereby, the contact area with the internal peripheral surface 214 of the catheter main body 21 in the intermediate part 73 of 7 A of front-end | tip members can be suppressed.

<Third Embodiment>
FIG. 5 is a partial longitudinal sectional view showing a third embodiment of the catheter assembly of the present invention.

Hereinafter, a third embodiment of the catheter assembly of the present invention will be described with reference to this figure, but the description will focus on the differences from the above-described embodiment, and the description of the same matters will be omitted.
This embodiment is the same as the first embodiment except that the configuration of the tip member is different.

  In the catheter assembly 1 shown in FIG. 5, the distal end member 7B has four pairs of plate-like links 76a and 76b that are rotatably connected to each other. For example, a wire can be used to connect the links 76a and 76b.

  The four sets of links 76 a and 76 b are arranged at equiangular intervals around the central axis of the drive shaft 4. The front ends of the four links 76a are connected so as to be rotatable. On the other hand, the base ends of the four links 76b are rotatably supported by the housing 51, respectively. Such a tip member 7B has a spindle shape as a whole, that is, the intermediate portion 73 has the largest outer diameter. Each intermediate portion 73 makes point contact with the inner peripheral surface 214 of the catheter body 21. Thereby, the contact area of the distal end member 7B and the inner peripheral surface 214 of the catheter main body 21 can be suppressed.

  The imaging core 3 can be brought into contact with the inner peripheral surface 214 of the catheter body 21 at each intermediate portion 73 by such a tip member 7B. Thereby, vibrations in the radial direction of the catheter main body 21 at the distal end side of the imaging core 3, particularly at the transmission / reception unit 52, can be suppressed or prevented. The distance to 214 can be kept substantially constant. As a result, appropriate adjustment is possible as described above.

  The link 76a and the link 76b are preferably biased toward the direction in which the angle θ formed by them increases.

Further, the link 76a and the link 76 b, because it is pivotally connected, the angle theta, is variable depending on the size of the internal diameter .phi.d ₂ of the catheter body 21.

For example, as shown in FIG. 5 (b), would constricted catheter body 21 is bent, the inner diameter .phi.d ₂ of the catheter body 21 of the catheter body 21 in a natural state where no external force is applied as shown in FIGS. 5 (a) If a reduced diameter than the inner diameter .phi.d _2, when trying to pass through the constricted portion 215 is the distal end member 7B, if the angle θ is a variable, be modified so that the tip member 7B also reduced in diameter And the passage is easy.

  The number of installation of the pair of links 76a and 76b is four in this embodiment, but is not limited to this, and may be three or five or more, for example.

<Fourth embodiment>
FIG. 6 is a partial longitudinal sectional view showing a fourth embodiment of the catheter assembly of the present invention.

  Hereinafter, a fourth embodiment of the catheter assembly of the present invention will be described with reference to this figure, but the description will focus on the differences from the above-described embodiment, and the description of the same matters will be omitted.

  This embodiment is the same as the second embodiment except that the catheter assembly further includes a rotational force relaxation means.

  In the imaging core 3 of the catheter assembly 1 shown in FIG. 6, a bearing 8 as a rotational force relaxation means is disposed between the distal end member 7 </ b> A and the housing 51. By this bearing 8, when the drive shaft 4 rotates, transmission of the rotational force to the tip member 7A is alleviated. Here, “relaxation” includes both a state where no rotational force is transmitted to the tip member 7A and a state where a part of the rotational force is transmitted to the tip member 7A.

  For example, when the catheter body 21 is bent and constricted and the distal end member 7A is positioned at the constricted portion, even if the drive shaft 4 rotates, the distal end member 7A is prevented from forcibly rotating due to the relaxation. Is done. Thereby, the rotation of the drive shaft 4 can be prevented from being inhibited, and at least one of them can be prevented from being damaged by the friction between the distal end member 7A and the catheter body 21.

  The torque reducing means is not limited to the bearing 8 and may be a clutch, for example.

  In addition, the image obtained by the catheter assembly is not limited to an optical image, but an intravascular ultrasonic diagnostic apparatus (IVUS: Intra Vascular Ultra Sound) that images a living tissue of a living body lumen using ultrasound. It can also be used. IVUS has an imaging core including a transducer unit for transmitting and receiving ultrasonic waves and a drive shaft for rotating the transducer unit, and a catheter body that covers the imaging core and is inserted into a living body lumen. Yes. The imaging core is movable in the axial direction within the catheter body. The catheter main body is formed with an acoustic window that can transmit ultrasonic waves from the transducer unit.

  When using an ultrasonic catheter, first, the imaging core is placed in the most distal side in advance in the catheter body, the catheter body is carried deeper than the affected area, and then only the imaging core is left with the catheter body left. Is retracted along the acoustic window from the distal end of the sheath and passed through the affected area. By retracting only the imaging core, the transducer unit moves from the deep part through the affected part, so that ultrasonic observation can be performed continuously before and after the affected part, and tomographic images of blood vessels and vessels, etc. Or create it. The optical image diagnostic apparatus and the ultrasonic diagnostic apparatus are collectively referred to as “image diagnostic apparatus” or “in-vivo intraluminal image diagnostic apparatus”.

  As mentioned above, although the catheter assembly of this invention was demonstrated about embodiment of illustration, this invention is not limited to this, Each part which comprises a catheter assembly is arbitrary structures which can exhibit the same function Can be substituted. Moreover, arbitrary components may be added.

  Further, the catheter assembly of the present invention may be a combination of any two or more configurations (features) of the above embodiments.

  In addition, the catheter body is not limited to a liquid outlet having a distal end opening that opens at the distal end, and may have, for example, a side hole that penetrates the side wall of the distal end.

DESCRIPTION OF SYMBOLS 1 Catheter assembly 2 Catheter 21 Catheter main body 211 Lumen 212 Opening 213 Gap 214 Inner peripheral surface 215 Constriction 22 Connector part 221 Liquid injection port 222 Rotation support part 23 Guide wire insertion part 24 Coil 25 Seal member 3 Imaging core 312 In Tube 313 Stopper 32 Unit connector 331 Outer tube 33 Relay connector 4 Drive shaft 41 Outer peripheral surface 5 Imaging means 51 Housing 511 Notch portion 52 Transmitter / receiver portion 53 Connector portion 54 Marker 56 Optical fiber 6 External unit 61 Scanner device 62 Axial moving device 63 Control part 64 Display part 7, 7A, 7B End member 71 End part 72 Base end part 73 Intermediate part 75 Wire 751 Communication part 76a, 76b Link 8 Bearing 200 Guide wire Q Liquid φd ₁ , φd ₃ outer diameter φd ₂ inner diameter

Claims (16)

A catheter body that is inserted into a living body lumen, has flexibility, and forms a tube;
A shaft that is inserted into the catheter body and used in an elongated shape and rotates about its axis;
An imaging unit having a transmission / reception unit that is fixed to a distal end portion of the shaft, rotates with the shaft, and faces the living body lumen to capture a signal for forming an image in the living body lumen;
A tip member supported on the tip side of the transmission / reception part of the shaft,
The distal end member has a columnar shape as a whole, and an outer diameter of an intermediate portion between the distal end portion and the proximal end portion is an outer diameter of the distal end portion, an outer diameter of the proximal end portion, and an outer diameter of the shaft. A catheter assembly that is larger than any outer diameter.   The catheter assembly according to claim 1, wherein the tip member has a function of suppressing or preventing vibration of the catheter body in a radial direction when the shaft rotates.   The catheter assembly according to claim 1 or 2, wherein the intermediate portion of the distal end member is in point contact or line contact with the inner peripheral surface of the catheter body.   The catheter assembly according to claim 1, wherein the tip member has elasticity.   The catheter assembly according to any one of claims 1 to 4, wherein the distal end member is formed by winding a wire rod in a spiral shape.   The catheter assembly according to claim 5, wherein the wire is wound in the same direction as the rotation direction of the shaft.   The catheter assembly according to claim 5 or 6, wherein the adjacent wires are spaced apart from each other.   The catheter set according to any one of claims 1 to 4, wherein the distal end member includes at least three pairs of links that are rotatably connected to each other at equal angular intervals around the central axis of the shaft. Solid.   The catheter assembly according to claim 8, wherein an angle formed by the pair of links is variable in accordance with a size of an inner diameter of the catheter body.   The catheter assembly according to any one of claims 4 to 9, wherein the tip member is freely expandable / reducing.   The catheter assembly according to any one of claims 1 to 10, wherein the distal end member is provided with a communication portion that communicates a distal end side and a proximal end side thereof.   The catheter assembly according to any one of claims 1 to 11, further comprising rotational force relaxation means for relaxing transmission of rotational force to the tip member when the shaft rotates.   The catheter assembly according to any one of claims 1 to 12, wherein the catheter body has an opening opened at a distal end thereof.   The catheter assembly according to any one of claims 1 to 13, wherein a guide wire insertion portion having a tubular shape through which a guide wire can be inserted is installed on an outer peripheral portion of the distal end of the catheter body.   The catheter assembly according to any one of claims 1 to 14, wherein the catheter body is filled with a liquid while the shaft is inserted. The transmission / reception unit is an optical lens and an optical mirror that perform near-infrared light projecting and receiving,
The catheter assembly according to any one of claims 1 to 15, wherein the imaging unit is configured to form the image based on information obtained from the near-infrared light.

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