JP3763978B2 - Ultrasound catheter - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an ultrasonic catheter system that is inserted into a body cavity such as a blood vessel or a vascular vessel to be used for displaying a cross-sectional image of a lumen or measuring a blood flow.
[0002]
[Prior art]
Ultrasound catheters are mainly used for the treatment of vascular stenosis as a means of treatment, whether they can only be expanded with a dilatation catheter, or a metal tube called a stent is placed. It is also used for observing the condition of the patient and also for observing the condition after treatment.
[0003]
Such a conventional ultrasonic catheter is connected to a drive device incorporating a motor, and the drive shaft is rotationally driven by this motor. The tip of the drive shaft is equipped with an ultrasonic transducer and rotates. By such a rotational motion, an ultrasonic wave is transmitted from an ultrasonic transducer attached to a distal end portion inserted into a body cavity such as a blood vessel, and an echo reflected by a reflector in the subject is received by the same ultrasonic transducer. After wave processing and amplification / detection processing, the image is displayed on a display such as a CRT.
[0004]
As described above, an ultrasonic catheter generally obtains an image by rotating and scanning an ultrasonic transducer provided at a distal end portion with a drive shaft. Since the ultrasonic transducer and the drive shaft rotate at a high speed, there is a risk of damage to the blood vessel wall or damage to the ultrasonic transducer when contacting the blood vessel wall. For this reason, the ultrasonic catheter conventionally used is configured so that the ultrasonic transducer and the drive shaft are rotatably accommodated in the catheter sheath and do not contact the blood vessel wall.
[0005]
Here, the ultrasonic catheter obtains a cross-sectional image in a direction perpendicular to the axis of the blood vessel at a position where the ultrasonic transducer is located in the blood vessel. Therefore, in order to observe the state of the blood vessel stenosis, the surgeon operates the ultrasonic catheter so that the distal end where the ultrasonic transducer exists passes through the stenosis. At that time, in order to know the state of the vascular stenosis part in detail, if the stenosis part is repeatedly observed, it is necessary to repeat the passage of the vascular stenosis part by the ultrasonic catheter each time. However, since it takes a considerable amount of labor to pass the narrowed blood vessel stenosis part without damaging it, it has been a heavy burden on the operator to repeat such work. In order to eliminate such a burden, an ultrasonic catheter having a function of moving only an internal ultrasonic transducer and a drive shaft while a catheter sheath is fixed has been proposed.
[0006]
When the surgeon takes the ultrasonic catheter to the vascular stenosis, the operator pulls the drive shaft while keeping the catheter sheath fixed at the intended position, and moves the ultrasonic transducer forward while moving the stenosis. Pass through and observe. This eliminates the need for the operator to repeatedly insert the ultrasonic catheter sheath through the stenosis. Such movement of the ultrasonic transducer may be performed by using a machine or by a doctor's hand.
[0007]
By the method described above, a 360 ° cross-sectional image of the surrounding tissue body spaced in the axial direction in the blood vessel can be obtained in a scanning manner up to an arbitrary position. At this time, the position / distance information such as the location of the stenosis part and its length is indicated by the catheter sheath displayed by the X-ray angiographic image when the state of the stenosis is confirmed by the blood vessel cross-sectional image displayed on the display. It is obtained by a radiopaque visual marker placed near the upper ultrasonic transducer.
[0008]
[Problems to be solved by the invention]
However, even in a stenosis that can be confirmed by a blood vessel cross-sectional image obtained by an ultrasonic catheter, depending on the shape of the stenosis, it is possible to accurately grasp diagnostic information such as the state of the stenosis by simply looking at the X-ray angiographic image. Often difficult to do. Therefore, in the case of a stenosis that cannot be confirmed with an X-ray angiography image in a relatively wide range or the like, the position / distance information from which the diagnostic information of the stenosis obtained from the blood vessel cross-sectional image is obtained from the X-ray angiography image It is hard to be fed back to the current situation. Therefore, matching between the diagnosis information of the stenosis and the position / distance information is qualitatively performed based on the experience and intuition of the doctor.
[0009]
The present invention has been made in view of such a problem, and is provided with a moving amount display means for displaying the moving amount of the position of the ultrasonic transducer in the longitudinal direction, so that only by looking at the X-ray angiographic image. Even for cases where the position / distance information of the stenosis cannot be grasped, the information on the position / distance of the stenosis is obtained even when the doctor manually manipulates the movement of the ultrasonic transducer under the blood vessel cross-section. An object of the present invention is to provide an ultrasonic catheter that can be accurately grasped.
[0010]
[Means for Solving the Problems]
In order to solve the above-described problems, in the present invention, a catheter sheath inserted into a body cavity or a lumen, a catheter sheath connector provided at the proximal end of the catheter sheath, and inserted into the catheter sheath, A drive shaft that transmits electrical and / or mechanical driving force from the proximal end side to the distal end side, an ultrasonic transducer fixed to the distal end side of the drive shaft, and the longitudinal movement of the drive shaft, An ultrasonic catheter comprising: a drive shaft connector inserted into the catheter sheath connector; and a movement amount display means for indicating a movement amount in a longitudinal direction of the ultrasonic transducer.
[0011]
Here, it is desirable that the drive shaft connector has a guide tube that is inserted into the catheter sheath connector and covers a predetermined proximal end portion of the drive shaft.
[0012]
Further, the movement amount display means includes a scale portion that quantitatively represents the movement amount of the ultrasonic transducer within the movable range of the ultrasonic transducer, and the movement of the ultrasonic transducer in the longitudinal direction. It is desirable to include an instruction marker that indicates the amount of movement of the ultrasonic transducer.
[0013]
Further, the movement amount display means may be a scale provided on the guide tube.
[0014]
In this way, even in cases where the position / distance information of the stenosis cannot be grasped only by looking at the X-ray angiographic image, the position / distance information of the stenosis is accurately obtained under vascular cross-section imaging. Since it can be grasped, the operator's discomfort and fatigue can be reduced.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0016]
(Embodiment 1)
FIG. 1 is a diagram illustrating an overall image of a system constituting an ultrasonic catheter according to an embodiment of the present invention. In FIG. 1, an ultrasonic catheter 1 has a catheter sheath 2 which is a long portion inserted into a body cavity, and a drive shaft and an ultrasonic transducer, which will be described later, are rotatably accommodated in the sheath 2. Yes. The proximal end portion of the ultrasonic catheter 1 is configured to be detachable from a drive device 31 incorporating a motor, and an image obtained by the ultrasonic transducer is displayed on an image monitor 32. The operation panel 33 is for adjusting the image and controlling the driving device 31, and the image recording device 34 is a video tape recorder for recording the obtained image.
[0017]
2 is a cross-sectional view of the distal end portion of the ultrasonic catheter 1 shown in FIG. 1, and FIG. 3 is a side cross-sectional view showing the structure of the proximal end portion of the ultrasonic catheter 1. In FIG. 2, reference numeral 3 denotes a drive shaft, which is inserted into the sheath 2, connected to the ultrasonic transducer 4 at the distal end portion of the sheath 2, and transmits a mechanical driving force from the proximal end portion to the distal end portion. A lead wire (not shown) for electrically driving the ultrasonic transducer 4 is included in the drive shaft 3. A coil 5 for rotational stabilization is provided at the tip of the ultrasonic transducer 4. In addition, a priming hole 6 for injecting an ultrasonic propagation substance such as physiological saline into the sheath 2 is provided at the distal end portion of the sheath 2.
[0018]
In FIG. 3, 7 is a sheath connector connected to the base end portion of the sheath 2, and is formed of a transparent or translucent resin. Reference numeral 8 denotes a drive shaft connector connected to the base end of the drive shaft 3. The sheath connector 7 includes a priming port 9 for discharging the internal gas when the priming liquid is injected from the priming hole 6, and the drive shaft connector 8 covers a predetermined portion of the base end of the drive shaft 3. However, a guide tube 10 slidable in the sheath connector 7 is provided.
[0019]
The sheath connector 7 includes a seal member 11 made of an O-ring for maintaining airtightness with the guide tube 10, and a screw portion 12, and a screw mechanism and a screw portion 12 provided in the pusher 13. As a result of the connection, the sealing material 11 is gripped.
[0020]
The base end portion of the drive shaft connector 8 is detachable from the drive device 31, and the rotary terminal 14 is engaged with the drive device 31 and rotates together with the drive shaft 3. The guide tube 10 includes a bulging portion 15 at the tip, and prevents the guide tube 10 from dropping from the sheath connector 7. The tip of the bulging portion 15 has an indicator marker 16 colored so that the position can be seen from the outside in the transparent or translucent sheath connector 7.
[0021]
FIG. 4 is an enlarged side view of a dotted line portion in FIG. 3 and is partially shown in cross section for easy understanding. A guide tube 10 is inserted into the transparent or translucent sheath connector 7, and an indication marker 16 provided at the tip of the guide tube 10 can be visually observed. A scale 17 is provided on the surface of the sheath connector 7, and the relative movement amount of the drive shaft connector 8 with respect to the sheath connector 7 from the initial position (a state in which the drive shaft connector 8 is inserted into the sheath connector 7 as far as possible). Can be confirmed. In the first embodiment, the indication marker 16 and the scale 17 constitute a movement amount display unit that indicates the movement amount of the ultrasonic transducer 4 from the initial position.
[0022]
Next, the operation method and operation of the movement amount display means according to the ultrasonic catheter of the present invention will be described.
[0023]
Referring to FIG. 3, drive shaft connector 8 is slid from right to left toward the drawing, and drive shaft connector 8 is brought into contact with the rear end surface of sheath connector 7 which is the initial position. At this time, it is confirmed that the instruction marker 16 is located at the origin (scale 0 position) of the scale portion 17.
[0024]
After inserting the distal end of the ultrasonic catheter 1 at an arbitrary position in the body cavity or lumen, the sheath connector 7 is fixed to the patient, and the drive device 31 is turned on to rotate the drive shaft 3 and Start a sonic scan. Next, the drive shaft connector 8 is manually moved to an arbitrary position in the longitudinal direction or automatically moved by a linear motion moving device (not shown) so as to be surrounded by a space in the body cavity or lumen in the axial direction. A cross-sectional image of 360 ° in the tissue can be obtained by scanning up to an arbitrary position. FIG. 5 is a view showing a state in which the ultrasonic catheter is inserted into the stenosis portion of the blood vessel and the ultrasonic transducer 4 is pulled toward the front side.
[0025]
At this time, the indwelling position of the distal end portion of the ultrasonic catheter 1 is set to a highly visible site such as a body cavity or a branch point in the lumen, and stenosis occurs in the body cavity or lumen from the cross-sectional image obtained in the scanning range. If recognized, the scanning position at the time of appearance and disappearance of the stenosis in the cross-sectional image is confirmed by the movement amount display means, so that the distance from the fixed position of the sheath 2 to the stenosis part, the axial length of the stenosis part, etc. Can know exactly. Therefore, it is possible to accurately grasp the position / distance information of the stenosis under the cross-section of the blood vessel even in cases where the position / distance information of the stenosis cannot be grasped only by looking at the X-ray angiographic image. Therefore, the operator's discomfort and fatigue can be reduced.
[0026]
(Embodiment 2)
In the above-described first embodiment, a transparent or semi-transparent sheath connector is used to check the internal indicating marker. However, in the present second embodiment, a scale is provided on the guide tube 10 to provide a sheath connector. It does not matter whether there is any material or indication marker. In addition, since the structure of the front-end | tip part and proximal end part of an ultrasonic catheter is common with the thing of Embodiment 1, description is abbreviate | omitted.
[0027]
FIG. 6 is a partial side view of the sheath connector 7 and the drive shaft connector 8 of the ultrasonic catheter according to the second embodiment of the present invention. In FIG. 6, a scale 18 is provided on the surface of the guide tube 10 of the drive shaft connector 8. The initial position is a state where both connectors are in close contact with each other, and the scale 18 is not visible at the initial position. Thereafter, when the drive shaft connector 8 is pulled toward the hand side, a graduation 18 gradually appears, and the position of the graduation 18 on the base end surface of the sheath connector 7 (the base end surface of the pusher 13) indicates the position from the initial position. The amount of movement of the acoustic transducer 4 can be grasped.
[0028]
It should be noted that the actual forms described above are described for facilitating the understanding of the present invention, and are not described for limiting the present invention. Therefore, each element disclosed in the above embodiment includes all design changes and equivalents belonging to the technical scope of the present invention.
[0029]
【The invention's effect】
According to the ultrasonic catheter of the present invention, the movement amount display means is provided in the drive shaft connector and the catheter sheath connector, whereby the movement amount in the longitudinal direction of the ultrasonic transducer can be accurately grasped.
[0030]
In addition, even in cases where the position / distance information of the stenosis cannot be grasped only by looking at the X-ray angiographic image, it is possible to accurately grasp the position / distance information of the stenosis under vascular cross-section imaging. Therefore, the operator's discomfort and fatigue can be reduced.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram for explaining the overall configuration of an ultrasonic catheter system according to the present invention.
FIG. 2 is a side sectional view showing an embodiment of an ultrasonic catheter proximal end portion in the present invention.
FIG. 3 is a cross-sectional view of the distal end portion of the ultrasonic catheter according to the embodiment shown in FIG.
FIG. 4 is an enlarged partial sectional view of a movement amount display means for displaying a position movement amount of the ultrasonic transducer according to the present invention.
FIG. 5 shows a state in which the ultrasonic catheter according to the present invention is inserted through a stenosis of a blood vessel.
FIG. 6 is an enlarged partial side view of movement amount display means according to the second embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Ultrasonic catheter 2 ... Catheter sheath 3 ... Drive shaft 4 ... Ultrasonic transducer 5 ... Coil 6 ... Priming hole 7 ... Sheath connector 8 ... Drive shaft connector 9 ... Priming port 10 ... Guide tube 11 ... Sealing material 12 ... Screw Part 13 ... Pusher 14 ... Rotating terminal 15 ... Swelling part 16 ... Indicator marker 17 ... Scale 18 ... Scale 31 ... Drive device 32 ... Image monitor 33 ... Operation panel 34 ... Video tape recorder

Claims (2)

A catheter sheath that is inserted into a body cavity or lumen;
A catheter sheath connector provided at the proximal end of the catheter sheath;
A drive shaft inserted into the catheter sheath and transmitting electrical and / or mechanical driving force from the proximal side to the distal side;
An ultrasonic transducer fixed to the tip side of the drive shaft;
Wherein performs position moving in the longitudinal direction of the drive shaft, wherein is inserted into the catheter sheath within the connector can slide the catheter sheath within the connector while not covering the proximal predetermined portion of the drive shaft, and from the catheter sheath connector A drive shaft connector having a guide tube with a bulging portion for preventing dropping ,
The ultrasonic catheter, wherein the guide tube or the catheter sheath connector includes a scale indicating the amount of movement in the longitudinal direction of the ultrasonic transducer.  The scale is a scale that quantitatively represents the amount of movement of the ultrasonic transducer within the movable range of the ultrasonic transducer, and the movement of the ultrasonic transducer as the ultrasonic transducer moves in the longitudinal direction. The ultrasonic catheter according to claim 1, further comprising an indication marker for indicating the amount.

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