JP2004337320A - Catheter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a catheter which prevents irregularities in rotation from being caused by a signal wire depending on the rotation even in the case of the catheter whose diameter is small enough to enable insertion into a blood vessel and which is equipped with a plurality of sensors. <P>SOLUTION: This catheter 1 comprises a rotary drive shaft 53 which is rotated in a prescribed direction, at least the two sensors 51 and 52 which are provided at the tip side of the shaft 53, and a plurality of signal cables 510 and 520 for pulling out electrical contacts of the sensors 51 and 52 to the outside; and the signal cables 510 and 520 are worked in such a manner as to be wound in a direction wherein a bundled state is loosened by the rotation of the shaft 53. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a catheter, and more particularly, to a catheter having a plurality of sensors for detecting information in a living body.
[0002]
2. Description of the Related Art In recent years, it is inserted into a coronary artery and other blood vessels of the heart, a lumen such as a bile duct, and a body cavity such as a urethra (hereinafter, collectively referred to as "lumen") to display a cross-sectional image of the body cavity and measure blood flow. An ultrasonic catheter is known as one of the biological measurement catheters for performing the above-described operations.
[0003]
Since the ultrasonic catheter is inserted into a meandering lumen, it is constituted by a flexible, long, thin tube. The tube is provided with a sensor section on the tip side inside. This sensor unit transmits and receives ultrasonic waves using an ultrasonic transducer and displays the ultrasonic waves on a monitor or the like of an external unit. Inside the tube, a cable that transmits an electric signal that connects the ultrasonic transducer at the tip and an external circuit, and a driving force transmission that mechanically rotates the sensor unit so that a predetermined region in the lumen can be observed at 360 ° The body (rotary drive shaft) is inserted.
[0004]
Here, in recent years, it has been required to obtain not only a single ultrasonic tomographic image but also a plurality of ultrasonic tomographic images having different image display ranges and various other diagnostic information. For this purpose, it is necessary to incorporate a plurality of sensors in the catheter, but providing a plurality of sensors leads to an increase in the diameter of the catheter. This is not only a matter of space for installing the sensor and the signal cable for it, but also a slight unevenness in rotation during rotation driving, which is a major cause that makes the operation of the rotation drive shaft unstable due to the small diameter. It is because it will not be possible. Reducing the diameter of the catheter is required to enable the insertion of the catheter into smaller blood vessels and vessels, and to enable the compounding with a treatment device, and these requirements are contradictory. .
[0005]
As an ultrasonic catheter having a plurality of sensors, an intrabody ultrasonic probe in which a plurality of ultrasonic transducers having different frequency characteristics are arranged has been proposed (for example, see Patent Document 1).
[0006]
The intracavity ultrasonic probe described in Patent Literature 1 includes two ultrasonic transducers having different frequency characteristics, and rotates two signal cables connected to these transducers at least in a portion corresponding to the inside of the curved portion, by rotating a drive shaft. It is characterized by being twisted in a direction that tightens in the direction. This is based on the idea that the signal cables are twisted in a tightening direction in the rotation direction in order to prevent the twisting of the signal cables from being unraveled by rotation and causing rotation unevenness.
[0007]
[Patent Document 1] Japanese Patent No. 3233976
[Problems to be solved by the invention]
However, the ultrasonic probe disclosed in Patent Literature 1 results in that the signal cable is firmly tightened by rotation, and the signal cable that is hardened is a thin ultrasonic probe that can be used for a blood vessel as a result. On the contrary, it is considered that this causes rotation unevenness. Such a phenomenon is not a problem with a relatively large-diameter ultrasonic probe used for diagnosing an organ such as a stomach wall as described in Patent Document 1, but is a problem with a small-diameter ultrasonic probe. This is because, in a small-diameter ultrasonic probe for a blood vessel or the like, the ratio of the hardness of the tight signal cable to the hardness of the probe itself is so large that it cannot be ignored.
[0008]
The present invention has been made in order to solve the above-mentioned problem, and provides a catheter in which a signal line does not cause rotation unevenness due to rotation even if the catheter has a sensor with a diameter small enough to be inserted into a blood vessel. The purpose is to do.
[0009]
[Means for Solving the Problems]
The object of the present invention is achieved by the following catheters (1) to (9).
[0010]
(1) It has a hollow rotary drive shaft that rotates in a predetermined direction, at least two sensors provided on the tip side of the rotary drive shaft, and a plurality of signal cables that lead out electrical contacts of the sensors to the outside. A catheter in which the signal cable is inserted into the hollow portion of the rotary drive shaft, wherein the signal cable is subjected to processing for bundling a plurality of the signal cables, and the processing is performed by rotation of the rotary drive shaft. A catheter characterized in that the bundle is wound in a loosening direction.
[0011]
(2) The process is a process in which a plurality of the signal cables are bundled and spirally wound, and the spiral process is a process in which the signal cable is wound in a direction in which the signal cable expands by rotation of the rotary drive shaft. The catheter according to the above (1), wherein:
[0012]
(3) The process is a process in which a plurality of the signal cables are twisted and bundled, and the process is a process in which the signal cables are twisted in a direction loosened by rotation of the rotary drive shaft. The catheter according to the above (1).
[0013]
(4) The catheter according to the above (1), wherein the processing is performed by spirally winding a plurality of the signal cables while bundling and twisting the signal cables.
[0014]
(5) The rotary drive shaft further includes a sensor mounting portion provided at a distal end portion thereof, and the sensors are two sensors provided on surfaces of the sensor mounting portion facing the axis of the catheter. The catheter according to any one of the above (1) to (4), characterized in that:
[0015]
(6) The catheter according to any one of (1) to (5), wherein the signal cable is formed by twisting at least two signal wires per one sensor.
[0016]
(7) The catheter according to the above (6), wherein the twisted signal lines are twisted in a direction in which the signal wires are loosened by rotation of the rotary drive shaft.
[0017]
(8) The catheter according to any one of (5) to (7), wherein each of the sensors is an ultrasonic transducer.
[0018]
(9) One of the above-mentioned sensors is an ultrasonic transducer, and the other is any one of a temperature sensor, a pressure sensor and an optical sensor. The catheter according to any one of the above.
[0019]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
[0020]
FIG. 1 is a view showing a catheter 1 of the present invention. FIG. 2 is a cross-sectional view showing a part of the distal end of the catheter 1. In FIG. 2, in order to show the features of the present invention, the dimensions are partially different from those of FIG.
[0021]
In FIG. 1, a catheter 1 is composed of a long sheath 2 inserted into a body cavity, and a connector 3 arranged at the user's hand side without being inserted into the body cavity for operation by a user. A guidewire lumen 4 is formed at the distal end of the sheath 2, and the sheath 2 has a continuous lumen formed from a connection portion with the guidewire lumen 4 to a connection portion with the connector 3.
[0022]
The sheath 2 includes a sheath distal end portion 21 that functions as a window for transmitting and receiving an ultrasonic wave, which will be described later, and a sheath proximal end portion 22 reinforced by a reinforcing layer 24. The sheath tip is formed of a single resin layer 23 so as not to hinder transmission and reception of ultrasonic waves. The sheath base end portion 22 adds the reinforcing layer 24 made of a braid (braid) of a metal pipe or a metal wire to the outer surface of the resin layer 23, and further covers the outer surface with the outer resin layer 25, thereby forming the reinforcing layer 24. It is sandwiched by a plurality of resin layers, and is connected to the connector 3. In the case of a metal pipe, it is preferable that the tip side is made flexible by inserting a helical slit only in the tip side of a metal pipe, and in the case of a blade, it is preferable that the tip side is made flexible by changing the knitting angle.
[0023]
The resin layer 23 is provided over the entire length of the sheath 2, but a material having flexibility and strength, for example, one layer of HDPE (High Density Polyethylene) or two layers of LLDPE (Low Level Density Polyethylene) is used. . However, not only this, but also polyolefins such as polyvinyl chloride, polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, polyesters such as polyethylene terephthalate and polybutylene terephthalate, polystyrene, polyurethane, polyamide Uses various resins such as polyimide, polyoxymethylene, polyvinyl alcohol, polytetrafluoroethylene, polyvinylidene fluoride, and other fluorine-based resins, thermoplastic elastomers such as polyamide elastomers and polyester elastomers, and various rubbers such as silicone rubber and latex rubber. it can.
[0024]
As described above, the sheath 2 has a base end formed of three layers of the resin layer 23, the reinforcing layer 24, and the outer resin layer 25, and has a middle portion in which the front end of the reinforcing layer is subjected to flexible processing. Since it is composed only of the resin layer 23, it becomes more flexible as it goes from the base end to the tip, and the outer diameter becomes thinner on the tip side, so that it is easy to reach the deep part and the operability is improved. Will do. In particular, it has one lumen, the rotary drive shaft 53 is inserted into this lumen, and the sensor part 5 is provided at the tip of the rotary drive shaft 53, and the sensor part 5 is made up of only the single resin layer 23. Therefore, the tip of the resin layer 23 alone serves as an ultrasonic window, so that transmission and reception of ultrasonic waves are performed smoothly, and accuracy or operability of ultrasonic diagnosis is improved.
[0025]
Further, a lubricating layer made of a hydrophilic polymer substance having lubricity in a wet state may be formed on the outer surface of the distal end side of the catheter 1 so that the catheter 1 can be smoothly inserted into the lumen. The lubricating layer made of a hydrophilic polymer substance extends from the distal end of the catheter 1 to the outer surface of the guide wire lumen 4 and the portion where the outer surface of the resin layer 23 is exposed (near the distal end of the reinforcing layer 24). Is desirably provided. If high lubricity is imparted to the entire catheter 1, the hand to be operated at the time of insertion into a lumen becomes slippery and handling becomes difficult. Further, it is desirable to provide a lubricating layer made of silicone or the like having a certain degree of lubricating property on the base end side where the lubricating layer made of a hydrophilic polymer substance is not provided, although the lubricating property is lower than that of the hydrophilic polymer substance. .
[0026]
The connector 3 includes a sheath connector 3a integrated with the base end of the sheath 2 and a drive shaft connector 3b integrated with the base end of the rotary drive shaft 53. A kink-resistant protector 32 is provided at a boundary between the sheath connector 3a and the sheath 2, thereby preventing bending (kinking) due to a sudden change in rigidity. The drive shaft connector 3b is provided with an injection port 31 to which a syringe (not shown) or the like can be attached in order to fill the entire lumen of the sheath 2 with the ultrasonic transmission liquid. The base end of the drive shaft connector 3b is connectable to a scanner device described later.
[0027]
As shown in FIG. 2, in the lumen of the sheath distal end portion 21, a sensor unit 5 having two ultrasonic transducers 51 and 52 on opposite surfaces is provided. The sensor unit 5 is configured such that two ultrasonic transducers 51 and 52 are fixed inside a short cylindrical metal pipe which is notched in two opposite directions. A rotation drive shaft 53 composed of a multilayer wound coil is connected to the base end side of the sensor unit 5. Further, a short coil member 54 is provided at the tip end side of the sensor unit 5 for the purpose of improving rotational stability.
[0028]
The ultrasonic transducers 51 and 52 can transmit and receive ultrasonic waves, respectively, and have different frequencies of transmitted and received ultrasonic waves. The transmission and reception frequencies of the ultrasonic transducers 51 and 52 are, for example, 50 MHz (megahertz) for the ultrasonic transducer 51 and 35 MHz for the ultrasonic transducer 52. As described above, by providing a plurality of ultrasonic transducers having different frequencies, it is possible to switch the range to be diagnosed according to the situation such as the diameter of a blood vessel and the depth of a lesion. That is, the high-frequency ultrasonic transducer 51 can obtain higher-resolution information than the low-frequency ultrasonic transducer 52, but on the other hand, the reachable range of the ultrasonic wave is narrow, and the vicinity of the catheter 1 is small. Since the diagnosis can be performed only for small blood vessels, it is suitable for diagnosing blood vessels having a small diameter and the vicinity of the blood vessel surface in more detail. The ultrasonic transducer 52 having a low frequency has a lower resolution than the ultrasonic transducer 51 having a higher frequency, but can obtain a wider range of information. Suitable for making a diagnosis. The preferred frequency of each ultrasonic transducer is 40 to 70 MHz for the high frequency ultrasonic transducer 51 and 20 to 40 MHz for the low frequency ultrasonic transducer 52. The difference between the frequencies of the two ultrasonic transducers is preferably 10 MHz or more, and the ratio of the frequencies of the two ultrasonic transducers is preferably 1.5 to 3. The reason why these numerical values are preferable is as follows.
[0029]
(1) If the difference between the frequencies of the transducers is too small, there will be no large difference in the diagnostic range and resolution, and a sufficient effect cannot be obtained.
[0030]
(2) In an ultrasonic catheter used for a coronary artery, the size of a transducer that can be used is 1 mm or less in diameter, but at this size, an ultrasonic transducer having a frequency characteristic of less than 20 MHz has a remarkably poor resolution. The frequency characteristic is desirably 20 MHz or more.
[0031]
(3) A frequency characteristic of 50 MHz or more is preferable for observing a plaque which is likely to be ruptured which may be present on the blood vessel wall surface.
[0032]
(4) When comparing the images obtained by the two ultrasonic transducers, it is difficult to grasp the positional relationship between the two images if the magnification ratio is too large, and if the ratio is too small, there will be a large difference in the diagnostic range and resolution. Thus, a sufficient effect of providing two transducers cannot be obtained.
[0033]
At the boundary between the sheath distal end portion 21 and the guide wire lumen 4, a discharge port 25 for discharging the ultrasonic transmission liquid filled from the proximal end to the distal end in the lumen of the sheath 2 is provided. . The discharge port 25 extends from the sheath distal end portion 21 to the inner surface of the guidewire lumen 4 and is formed by a reinforcing member 26. A coil-shaped X-ray contrast marker 27 is provided on the base end side of the reinforcing member 26 so as to be in close contact with the inner surface of the sheath 2. The X-ray contrast marker 27 can confirm the position of the sensor unit 5 under X-ray fluoroscopy at the time of insertion into a body cavity, and also has a role of a buffer material so that a sudden change in physical properties does not occur at the base end of the reinforcing member 26. ing. The coil member 54 is configured to partially enter the inside of the X-ray contrast marker 27 for the same purpose.
[0034]
The guide wire lumen 4 has a hole into which the guide wire 100 can be inserted. The guidewire 100 is used to be inserted into a body cavity in advance and guide the catheter 1 to an affected part. The catheter 1 is guided to the affected part while passing the guidewire 100 through the guidewire lumen 4. An X-ray contrast marker 41 is embedded in the wall forming the guide wire lumen 4 so that the distal end position of the catheter 1 can be confirmed under X-ray fluoroscopy when inserted into a body cavity. The guidewire lumen 4 is formed by inserting and fixing a relatively short tube 42 inside the resin layer 23 constituting the sheath distal end portion 21. The axial length of the tube 42 is preferably about 5 to 50 mm. If the length is longer than 50 mm, the distance from the distal end of the catheter 1 to the sensor unit 5 is too long, so that it is difficult to reach the sensor unit 5 to a target site deep in the blood vessel. On the other hand, if it is shorter than 5 mm, the ability to follow the guide wire will be poor.
[0035]
FIG. 3 is a sectional view for explaining the sensor unit 5. As shown in FIG. 3, the front and back surfaces of the ultrasonic transducer 51 provided in the sensor unit 5 are connected to a pair of signal lines 511 and 512, and the front and back surfaces of the ultrasonic transducer 52 are connected to a pair of signal lines. The signal lines 521 and 522 are connected. The ultrasonic transducers 51 and 52 are fixed by a potting agent 56 in a housing 55 formed by cutting two metal pipes. Between the ultrasonic transducers 51 and 52, a back member 57 common to both transducers is provided.
[0036]
The signal lines 511, 512, 521, and 522 are respectively coated with insulation, inserted through the hollow portion of the rotary drive shaft 53, and extend to the connector 3. The signal lines 511, 512, 521, and 522 themselves have a form in which a plurality of conductive wires are insulated and coated in a twisted state. In FIG. 3, the base end of the pair of signal lines 511 and 512 is illustrated as one cable 510 from the drawing relationship, and the base end of the pair of signal lines 521 and 522 is similarly set as one cable. Although shown as 520, it is actually a stranded wire processed in an independent state. Hereinafter, the pair of signal lines 511 and 512 may be referred to as a signal cable 510, and the pair of signal lines 521 and 522 may be referred to as a signal cable 520 for simplification of description. The signal cable 510 and the signal cable 520 are collectively spirally wound over the entire length.
[0037]
As a material forming the conductor, a metal or alloy such as Cu, Au, Ag, and Fe is suitable. The outer diameter of the conducting wire is preferably as large as possible as long as the operability of the catheter 1 is not impaired, and is preferably from 10 to 200 μm, and more preferably from 16 to 50 μm. In addition, the number of twisted conductors may be two or more, but it is preferable that the number of twisted conductors is an odd number with a stable twisted shape, and it is preferable that the number of twisted conductors be three to five. Further, as a material constituting the insulator covering the conductor, a high insulating resin such as a urethane-based, polyimide-based, or fluorine-based resin is preferable, and the coating thickness may be thin as long as a desired withstand voltage is obtained. Is preferably 5 μm or more, more preferably 10 to 30 μm.
[0038]
As described above, by forming a signal line by twisting a plurality of conductive wires, it is possible to reduce the transmission loss in the signal line while facilitating the bending of the signal line. Reduction of the transmission loss is particularly effective when the frequency of the signal transmitted through the signal line is high. At a high frequency, the current flowing through the conductor is concentrated on the surface due to the skin effect, but the surface area of the conductor can be increased by forming one signal line by a plurality of conductors.
[0039]
The rotation drive shaft 53 is formed of a close-wound coil made of metal. The rotation drive shaft 53 has, for example, a three-layer structure in which a plurality of coils are wound so as to have flexibility and rotational torque transmission characteristics. For example, a right-handed layer-a left-handed layer-a right-handed layer such as The tubular body has a configuration in which the winding directions are alternately changed, and the outer diameter is constant from the start end to the end. With this configuration, when a torsional force is applied, the coils of the respective layers are mutually tightened, and torque transmission is reliably performed. However, the winding direction or the number of layers to be wrapped can be freely selected depending on each model, performance, and the like. As a specific example of the drive shaft 53, stainless steel, a piano wire, a superelastic alloy or the like having a diameter or a thickness of 0.001 to 0.5 mm is formed in a hollow coil shape having an outer diameter of 0.1 to 4 mm. Things. The rotation speed of the rotary drive shaft 53 varies depending on the pathological condition or the part to be diagnosed, but is generally 30 times / sec because the monitor image is 30 frames / sec.
[0040]
The rotation of the rotary drive shaft 53 allows the interior of the lumen to be observed at 360 degrees, but to observe a wider range, the rotary drive shaft 53 may be moved in the axial direction. FIG. 4 is a diagram illustrating a state in which the rotary drive shaft 53 is relatively moved with respect to the sheath 2. As shown in FIG. 4, if the sheath connector 3a is fixed and the drive shaft connector 3b is pulled out and moved toward the proximal end, the internal rotary drive shaft 53 and the sensor unit 5 fixed to the distal end thereof are axially moved. Will be moved to. This axial movement may be performed manually by the operator, or may be performed electrically by an external unit described later. Inside the sheath connector 3a, a pipe 33 that covers the rotary drive shaft 53 and whose base end is fixed to the drive shaft connector 3b is slidably inserted. The pipe 33 is provided for the purpose of preventing the rotation drive shaft 53 from being exposed to the outside when the rotation drive shaft 53 is pulled out to the base end side. A stopper 34 is provided at the end of the pipe 33 to prevent the pipe 33 from falling off the sheath connector 3a.
[0041]
FIG. 5 is a cross-sectional view of the drive shaft connector 3b and a diagram for explaining the configuration of the external unit. The external unit controls a scanner device 61 having a built-in external drive source such as a motor, an axial moving device 62 for holding the scanner device 61 and moving it in the axial direction by a motor or the like, and a scanner device 61 and an axial moving device 62. And a display unit 64 for displaying an image obtained by the sensor unit 5. The axial moving device 62 includes a scanner grip 621 that grips and fixes the scanner 61, and a connector grip 622 that grips the sheath connector 3a.
[0042]
The drive shaft connector 3b has a port 31 for injecting physiological saline for priming. A rotor 36 for transmitting the rotation of a motor (not shown) provided in the scanner device 61 to the rotary drive shaft 53 through an O-ring 35 for sealing a physiological saline solution, at the base end side of the rotary drive shaft 53. Connected to A 4-pole male connector 37 to which the base ends of the signal cables 510 and 520 are connected is connected to the rotor 36, and is electrically connected to a 4-pole female connector (not shown) provided in the scanner device 61.
[0043]
The scanner device 61 is connected to the four-pole male connector 37 to transmit and receive signals from the sensor unit 5 and transmit a driving force for rotating the rotary drive shaft 53. Here, the direction of rotation generated by the scanner device 61 is arbitrary, but is assumed to rotate only in a certain direction. In the present embodiment, for the sake of explanation, the following description is based on the assumption that the catheter 1 rotates clockwise when facing the distal end of the catheter 1.
[0044]
In the present embodiment, as described above, the signal cables 510 and 520 inserted into the rotary drive shaft 53 are spirally wound. At this time, the signal cables 510 and 520 are wound clockwise in the traveling direction when facing the distal end of the catheter 1 in the same manner as the rotation direction of the rotary drive shaft 53. Thus, the spiral wound in the same direction as the rotation direction acts so that the spiral is unwound and spread by the rotation. Therefore, the signal cables 510 and 520 of the present embodiment have the effect of unwinding the spiral and expanding the diameter by the rotation of the rotary drive shaft 53 by the scanner device 61. The expanded signal cables 510 and 520 spread over the entire lumen of the rotary drive shaft 53 and are maintained in close contact with the inner surface of the rotary drive shaft 53. As described above, since the signal cables 510 and 520 are held in a spread state, the signal cables 510 and 520 do not become harder any more, which hinders the rotation of the rotation drive shaft 53 and causes rotation unevenness. Will not be. Further, since the spirally wound signal cable has elasticity in the axial direction of the catheter 1, it is possible to obtain an effect of improving the curve following ability of the catheter 1 when inserted into a curved body cavity.
[0045]
For the same reason, the signal lines 511 and 512 constituting the signal cable 510 are twisted in a direction in which the signal lines 511 and 512 expand by rotation (clockwise toward the distal end), and the signal lines 521 and 522 constituting the signal cable 520 are also Twist in the direction swelled by rotation (clockwise facing the tip).
[0046]
Next, a method of using the catheter 1 according to the present embodiment will be described.
[0047]
First, the surgeon prepares the catheter 1 in the state shown in FIG. 1, connects a syringe (not shown) to the injection port 31, and injects (primes) an ultrasonic transmission liquid (such as saline). Whether or not the filling of the liquid has been completed can be visually confirmed based on whether or not the ultrasonic transmission liquid that has passed through the discharge port 25 at the distal end of the sheath 2 has been discharged from the guide wire lumen 4 to the outside.
[0048]
When the priming is completed, the operator passes the proximal end of the guide wire 100 already introduced into the blood vessel through the distal end of the guide wire lumen 4 and introduces the catheter 1 into the blood vessel along the guide wire 100 as it is. At this time, the catheter 1 is introduced into a guiding catheter (not shown). However, the use of the guiding catheter itself is generally used in catheter surgery, and is well-known and will not be described.
[0049]
In the blood vessel, the position of the catheter 1 in the living body is confirmed while observing the position of the X-ray opaque X-ray contrast markers 41 and 27 under the X-ray image.
[0050]
When the distal end of the catheter 1 reaches a target position in the blood vessel, the scanner device 61 and the connector 3 are connected. When the scanner device 61 is rotationally driven, its rotational force is transmitted to the rotational drive shaft 53, and the electric signal from the control unit 63 is transmitted to the sensor unit 5 via the 4-pole male connector 37 and the signal lines 510 and 520. It is transmitted to the sound wave transducers 51 and 52.
[0051]
Therefore, the ultrasonic transducers 51 and 52 emit ultrasonic waves in pulses while rotating within the sheath 4, and the ultrasonic waves reach the affected part via the ultrasonic transmission liquid, and then are reflected by the blood vessel wall and the like. The reflected waves are received when the ultrasonic transducers 51 and 52 are not transmitting, and are transmitted to the control unit 63 via the signal lines 510 and 520. The control unit 63 internally processes this, converts it into a video signal, and displays it on the display unit 64.
[0052]
The control unit can control to display one or both of the ultrasonic transducers 51 and 52 at the same time as necessary.
[0053]
In the present embodiment, the signal cable and the signal line are wound in such a direction that the signal cable and the signal line are loosely spread due to the rotation at the time of such observation or diagnosis.
[0054]
In the signal cable according to the present embodiment, for example, a single core wire made of a metal wire such as SUS, Cu, or the like is prepared, wound horizontally around the core wire, and thereafter, the core metal 301 is pulled out until a desired outer diameter is obtained. It can be processed by extending (pulling in the left-right direction) the wound core cable 204. At this time, in order to enhance the shape retention after processing, it is possible to perform weak heating, but it is not preferable that the shape remains too strong, since this leads to rigidification of the signal line.
[0055]
(Modification 1)
FIG. 6 is a diagram illustrating a configuration of a signal line and a sensor unit as a modification of the first embodiment. FIG. 6 shows only two ultrasonic transducers and four signal lines connected thereto. These members are mounted in a housing or a rotary drive shaft as in the first embodiment shown in FIG. The first modification is the same as the first embodiment except for the method of processing the signal lines (signal cables), and thus the description other than the differences is basically omitted.
[0056]
The signal lines 511 ′ and 512 ′ electrically connected to both surfaces of the ultrasonic transducer 51 are twisted with each other to form a signal cable 510 ′, as shown in FIG. The direction of twisting is a direction in which the wire is loosened by rotation (in the present embodiment, a clockwise direction toward the distal end). As shown in FIG. 6, signal lines 521 ′ and 522 ′ electrically connected to both surfaces of the ultrasonic transducer 52 are also loosened by rotation (in the present embodiment, clockwise toward the distal end side). ) To form a signal cable 520 ′. The steps up to here are common to the first embodiment.
[0057]
In the first modification, the signal cables 510 ′ and 520 ′ are twisted with each other. The twisting direction is a direction in which the twisting is loosened by the rotation of the rotary drive shaft 53. Therefore, the signal cables 510 ′ and 520 ′ according to the present embodiment have the effect of being untwisted and loosened by the rotation of the rotary drive shaft 53 by the scanner device 61. The loose signal cables 510 ′ and 520 ′ are spread over the entire lumen of the rotary drive shaft 53, and are maintained in a state of being in close contact with the inner surface of the rotary drive shaft 53. By holding the signal cables 510 'and 520' in the spread state in this way, the signal cables 510 'and 520' do not become harder any more, and hinder the rotation of the rotary drive shaft 53 and rotate. It does not cause unevenness.
[0058]
Further, since each signal cable itself is a stranded wire of a pair of signal lines, it is possible to reduce interference of electric signals propagating through each pair of signal lines and to reduce generation of noise. Here, by making the twist pitch of each pair of signal lines different, a difference in frequency characteristics of each pair can be obtained, so that signal interference can be further reduced. Further, since the signal cables are also twisted, signal interference can be further reduced.
[0059]
In FIG. 6, the plurality of signal cables 510 'and 520' are bundled in a state where twisting and spiral winding are combined. By taking such a form, it is possible to obtain the effect of not causing rotation unevenness, improving the followability of the curvature of the catheter 1, and reducing the signal interference.
[0060]
(Other modifications)
Although the above embodiment and Modification 1 relate to a catheter having two ultrasonic transducers having different transmission / reception frequencies, other sensor means can be provided.
[0061]
For example, it may have one ultrasonic transducer, and a sensor for detecting temperature, blood pressure, blood flow velocity, blood component, PH, etc. may be provided on the back side. Since these sensors basically need to be in contact with blood, the configuration is slightly different from that of the catheter of the embodiment, and it is necessary to provide a relatively large opening for introducing blood into the sheath. Since the catheter with a sensor itself is known, a detailed description thereof will be omitted.
[0062]
Even in such a sensor, the points to which the signal lines are connected are the same as those of the catheter 1 described in the embodiment, and a point that a plurality of signal lines are spirally wound or twisted in a direction loosened by rotation. Is the same.
[0063]
The present invention is not limited to only the above-described embodiments, and various modifications can be made by those skilled in the art within the technical concept of the present invention. For example, the catheter has a single lumen, but may have a plurality of lumens. In addition to the catheter using ultrasound, other catheters such as optical coherence tomography (OCT) are used. Also applicable to diagnostic catheters.
[0064]
【The invention's effect】
According to the present invention, it is possible to obtain a catheter having a plurality of sensors with reduced rotation unevenness while reducing the diameter.
[0065]
Further, since the spirally wound signal cable has elasticity in the axial direction of the catheter 1, it is possible to obtain an effect of improving the curve following ability of the catheter 1 when inserted into a curved body cavity.
[0066]
Further, by making each signal cable a stranded wire of a pair of signal lines, it is possible to reduce interference of electric signals propagating through each pair of signal lines.
[Brief description of the drawings]
FIG. 1 is a view showing a catheter 1 according to an embodiment of the present invention.
FIG. 2 is a sectional view of a distal end portion of the catheter 1 of FIG.
FIG. 3 is a cross-sectional view for explaining a structure of a sensor unit 5;
FIG. 4 is a diagram illustrating a state in which a sensor unit 5 is retracted in an axial direction.
FIG. 5 is a sectional view showing a structure of a proximal end portion of the catheter 1 and a conceptual diagram showing a relationship between the catheter 1 and an external unit.
FIG. 6 is a diagram illustrating a configuration of a signal cable according to a first modification.
[Explanation of symbols]
1 catheter
2 sheath
3 hub
4 Guidewire lumen
5 Sensor section
51,52 Ultrasonic transducer

Claims (9)

A hollow rotary drive shaft that rotates in a predetermined direction, at least two sensors provided on the distal end side of the rotary drive shaft, and a plurality of signal cables that lead out electrical contacts of the sensors to the outside; A catheter in which a cable is inserted into a hollow portion of the rotary drive shaft, wherein the signal cable has been subjected to a process of bundling a plurality of the signal cables, and the process is performed by bundling the rotation drive shaft. A catheter wound in a loosening direction. The process is a process in which a plurality of the signal cables are bundled and spirally wound, and the spiral process is wound in a direction in which the signal cable is expanded by rotation of the rotary drive shaft. The catheter according to claim 1, wherein 2. The method according to claim 1, wherein the processing is performed by twisting and bundling a plurality of the signal cables, and the processing is twisted in a direction in which the signal cables are loosened by rotation of the rotary drive shaft. A catheter according to claim 1. 2. The catheter according to claim 1, wherein the processing is a processing in which a plurality of the signal cables are bundled and twisted and further spirally wound. The rotary drive shaft further includes a sensor mounting portion provided at a distal end portion thereof, wherein the sensors are two sensors provided on surfaces of the sensor mounting portion facing the axis of the catheter. The catheter according to any one of claims 1 to 4, wherein The catheter according to any one of claims 1 to 5, wherein the signal cable is formed by twisting at least two signal lines per one sensor. The catheter according to claim 6, wherein the twisted signal lines are twisted in a direction loosened by rotation of the rotary drive shaft. The catheter according to any one of claims 5 to 7, wherein each of the sensors is an ultrasonic transducer. 9. The catheter according to claim 1, wherein one of the sensors is an ultrasonic transducer, and the other is one of a temperature sensor, a pressure sensor and an optical sensor.

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