JP2017164387A - Catheter and image diagnostic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a catheter for diagnostic imaging, expanding a distance range without substantially changing a configuration related to pull-back in a motor derive unit (MDU) provided in an image diagnostic apparatus.SOLUTION: The catheter includes: a connector (210) provided at an outer tube to be fixed to a base part of a motor drive unit provided in a diagnostic imaging apparatus, for pulling out a drive shaft of an imaging core from the outer tube, along with an inner tube; a slider member (250) that is movable along with the inner tube in a direction of pulling out the inner tube from the outer tube, is also movable in a direction orthogonal to the pulling direction, and pushes out the drive shaft by the moving in the orthogonal direction; and a plate member (240) whose both ends are supported by the connector and the slider member, the plate member being bent in the orthogonal direction, and composed of a non-stretchable material.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a diagnostic catheter and an diagnostic imaging apparatus using the same.

  In an image diagnostic apparatus using ultrasound, a catheter (or probe) that is inserted into a blood vessel of a subject is used. This catheter has an inner tube that rotatably accommodates the imaging core and an outer tube that accommodates the inner tube. The imaging core has a transmission / reception unit for transmitting / receiving ultrasonic waves at the tip, and has a drive shaft for causing the transmission / reception unit to rotate and move in the axial direction. The drive shaft accommodates signal lines for causing the transmission / reception unit to emit ultrasonic waves and for transmitting an electrical signal indicating the detection result of the ultrasonic waves reflected from the vascular tissue to the diagnostic apparatus.

  A catheter is also used in an image diagnostic apparatus using optical interference. The catheter also has an inner tube containing the imaging core and an outer tube containing the inner tube. The imaging core has a transmission / reception unit for transmitting and receiving light at the tip, and a drive shaft for causing the transmission / reception unit to rotate and move in the axial direction. The drive shaft contains an optical fiber for emitting light from the transmission / reception unit and for transmitting light reflected from the vascular tissue to the diagnostic apparatus.

  Comparing the ultrasonic tomographic image with the optical coherent tomographic image, the ultrasonic tomographic image is superior to the optical coherent tomographic image in that an image up to a deep part of the vascular tissue is obtained, but the inner wall of the blood vessel or a relatively shallow image The optical coherence tomographic image is excellent in the image quality of the part. Focusing on this point, recently, a diagnostic device using a catheter equipped with both an ultrasonic transmission / reception unit and an optical transmission / reception unit has also appeared (Patent Document 1).

  When performing a scanning operation for obtaining an intravascular tomographic image of a patient using the catheter, the rear end of the catheter is attached to a motor drive unit (hereinafter referred to as MDU) included in the diagnostic imaging apparatus. This MDU functions as a relay device between the catheter and the diagnostic device, and rotates the imagen core (drive shaft) in the catheter and pulls the imaging core (pullback). Is stored. Therefore, the MDU is also called a pullback unit. Although the forward operation is possible when the drive motor is rotated in the reverse direction, only the pullback operation will be described here.

International Publication No. 2014/049634

  The blood vessel to be diagnosed by conventional image diagnostic apparatuses is the coronary artery. Therefore, the moving distance of the imaging core in one scan is about 15 cm with respect to the axial direction of the blood vessel axis. That is, the MDU only needs to have a structure capable of pulling back the imaging core in the catheter by about 15 cm.

  Recently, there has been an increasing demand for obtaining a longer blood vessel image in a single scan, not limited to the coronary artery. For example, in the case of a lower limb blood vessel, it is desired to obtain an image in a range of about 30 cm along the blood vessel axis by a single scan. Simply, the size of the MDU in the longitudinal direction should be doubled in order to pull back the imaging core over 30 cm, which is twice as much as before.

  However, since there are a number of medical devices in the operating room, it is often difficult to maintain the MDU installation area. Therefore, we want to avoid the increase in the size of the MDU. In addition, increasing the number of MDU varieties increases the burden on medical institutions such as the need for additional storage locations, and there is a possibility that the catheter and MDU may be damaged due to an incorrect combination of the catheter and the MDU.

  The present invention has been made in view of such a problem, and an object of the present invention is to provide a catheter capable of extending the movement range of the pullback without substantially changing the configuration related to the pullback in the motor drive unit (MDU) of the diagnostic imaging apparatus. To do.

In order to solve the above problems, for example, the catheter of the present invention has the following configuration. That is,
A diagnostic imaging catheter having an inner tube containing a drive shaft of an imaging core and an outer tube containing the inner tube,
A connector provided on the outer tube for fixing the drive shaft to the base portion of the motor drive unit of the diagnostic imaging apparatus in order to pull out the drive shaft from the outer tube together with the inner tube;
It is movable with the inner tube in the pulling direction of the inner tube with respect to the outer tube, and is movable in a direction orthogonal to the pulling direction, and by moving in the orthogonal direction, the imaging core A slider member that pushes the drive shaft;
Both ends are supported by the connector and the slider member, bent in an orthogonal direction, and have a plate member made of a non-stretchable material.

  According to the present invention, it is possible to extend the pullback range so far without substantially changing the configuration related to pullback in the MDU.

It is a figure which shows the external appearance structure of the diagnostic imaging apparatus concerning embodiment. It is a figure which shows the edge part structure of the side connected with MDU in the catheter in embodiment. It is a partial exploded perspective view in the edge part of the catheter in embodiment. It is a figure which shows transition of the catheter at the time of pull back operation | movement in MDU.

  Hereinafter, embodiments according to the present invention will be described in detail with reference to the accompanying drawings. The embodiments described below are preferable specific examples of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention is particularly described to limit the present invention. As long as there is not, it is not restricted to these aspects.

  FIG. 1 shows an external configuration of an image diagnostic apparatus 100 using ultrasonic waves in the embodiment.

  As shown in FIG. 1, the diagnostic imaging apparatus 100 includes a catheter 101, a motor drive unit (hereinafter referred to as MDU) 102, and an operation control apparatus 103. The MDU 102 and the operation control device 103 are connected by a cable 104 that accommodates various signal lines.

  In the operation control apparatus 103, reference numeral 111 denotes a main body control unit. This main body control unit 111 is a line extending in the radial direction from the rotation center position from the signal (electric signal indicating the reflected wave of the ultrasonic wave emitted toward the vascular tissue) obtained by the imaging core housed in the catheter 101. Generate data. Then, a blood vessel cross-sectional image based on ultrasound is generated through line data interpolation processing.

  Reference numeral 111-1 denotes a printer and a DVD recorder, which prints processing results in the main body control unit 111 or stores them as data. Note that the storage destination of the processing result may be a server, a USB memory, or the like, and the type thereof is not limited. Reference numeral 112 denotes an operation panel, and the user inputs various setting values and instructions via the operation panel 112. Reference numeral 113 denotes a monitor (for example, LCD) as a display device, which displays various cross-sectional images generated by the main body control unit 111. Reference numeral 114 denotes a mouse as a pointing device (coordinate input device).

  The catheter 101 is inserted directly into the blood vessel. The catheter 101 is configured by an inner tube that accommodates a rotatable imaging core that is movable in the longitudinal direction and an outer tube that accommodates the inner tube. A distal end of the imaging core is provided with a housing that contains a transmission / reception unit that generates an ultrasonic wave based on a signal transmitted from the diagnostic imaging apparatus 100 and receives an ultrasonic wave reflected from a vascular tissue and converts it into an electrical signal. ing. A drive shaft for transmitting the rotation and moving force of the imaging core from the MDU 102 is connected to the housing. That is, the imaging core is composed of the housing and the drive shaft. In the diagnostic imaging apparatus 100, the state inside the blood vessel is measured by using this imaging core.

  The MDU 102 has a portion that engages with a connection portion at the rear end of the catheter 101, and functions as a relay device between the transmission / reception unit and the operation control device 103 in the catheter 101 when connected to the catheter 101. That is, the MDU 102 has a function of transmitting an ultrasonic drive signal from the operation control device 103 to the transmission / reception unit and transmitting an electrical signal indicating a reflected wave from the living tissue detected by the transmission / reception unit to the operation control device 103. .

  Further, the MDU 102 is provided with various switches and buttons, and an operator (physician or the like) operates this to rotate the imaging core in the catheter 101 and pull back (movement of the imaging core). It will be. For this reason, the MDU 102 incorporates therein a motor for rotating the imaging core and a motor for performing pullback.

  The actual patient's blood vessel pull-back scanning process is well-known, but will be briefly described here.

  The operator confirms that the distal end portion of the catheter 101 has moved to the position to be diagnosed while viewing the X-ray image. Then, the operator operates the MDU 102 to instruct pull back. As a result, the ultrasound transmitting / receiving unit located at the distal end of the catheter 101 moves along the axis of the blood vessel while rotating. The transmission / reception unit, for example, emits and receives 512 ultrasonic waves during one rotation, and transmits the received signal to the operation control apparatus 103 via the MDU 102. The operation control apparatus 103 receives this signal and performs predetermined calculation processing to obtain 512 line data extending in the radiation direction from the rotation center of the transmission / reception unit. This line data is dense at the center of rotation, and becomes coarser with distance from the center of rotation. Therefore, in order to obtain a two-dimensional image visually recognized by a human, the operation control apparatus 103 performs an interpolating process between the lines and a process of generating pixels between the lines. As a result, a vascular tomographic image in a direction orthogonal to the axial direction of the blood vessel can be generated. By the pull back operation by the MDU 102, the transmission / reception unit of the imaging core moves along the blood vessel axis. Therefore, it is possible to generate a three-dimensional image of a blood vessel by joining the blood vessel tomographic images at the positions on the blood vessel axis every rotation of the transmission / reception unit. The doctor diagnoses the blood vessels of the patient from the image obtained by such a scan.

  The above is the outline of the operation at the time of pull back scanning in the embodiment. Next, the catheter 101 in the embodiment will be described.

  As described above, the catheter 101 has a rear end connected to the MDU 102 when an intravascular image of a patient is obtained. The present embodiment is characterized in that when the MDU 102 pulls back the inner tube of the catheter 101 and the drive shaft of the imaging core by a distance L, the imaging core moves by 3L, which is three times as much. Hereinafter, the configuration and principle for that purpose will be described.

  FIG. 2 is a structural diagram of the rear end portion (connection side with the MDU 102) of the catheter 101 in the embodiment.

  The catheter 101 includes an inner tube 202 that houses the imaging shaft drive shaft 203 and an outer tube 201 that houses the inner tube 202. A unit connector 210 is provided at the end of the outer tube 201, and a concave portion 210 a for fixing to the MDU 102 is further provided in the unit connector 210. The unit connector 210 is integrally provided with a leaf spring pusher 215 described later. One end of a metal leaf spring 240 is fixed to the leaf spring pusher 215.

  In addition, a joint 211 for connecting to a coupling portion in the MDU 102 is provided at the end of the drive shaft 203. When the joint 211 is connected to the coupling portion of the MDU 102, the ultrasonic transmission / reception unit in the imaging core and the operation control device 103 are electrically connected. In addition, the MDU 102 rotates the drive shaft 203.

  Reference numeral 250 shown in the figure is a slider member. Further, the slider member 250 is provided with a U-shaped guide hole or groove for guiding the drive shaft 203 of the imaging core. The slider member 250 is provided with a locking portion 251 that locks one end of the leaf spring 240.

  Reference numerals 230 and 231 denote connector hubs that move together with a pull-back moving slider (not shown) of the MDU 102 when attached to the MDU 102. The connector hubs 230 and 231 sandwich the slider member 250 so as to be slidable in the vertical direction of the drawing. Each of the connector hubs 230 and 231 is provided with a guide hole corresponding to a quadrant as shown in order to guide the drive shaft 203. Of course, the guide hole is made of a material that reduces friction with respect to the drive shaft 203. Further, the connector hub 230 is integrated with the inner tube 202.

  Reference numeral 232 denotes a leaf spring guide member. As shown in the figure, a guide groove 233 for guiding the leaf spring 240 is provided along its longitudinal direction. The leaf spring guide member 232 and the connector hubs 230 and 231 are integrated.

  FIG. 3 is a perspective view of the catheter 101 of the embodiment as viewed from the leaf spring guide member 232 side. In the drawing, for easy understanding, the inner tube 202 and the drive shaft 203 are shown through a part of the outer tube 201.

  The structure of the rear end portion of the catheter 101 in the embodiment has been described above. Next, the movement at the time of pullback in a state where the catheter 101 is attached to the MDU 102 will be described with reference to FIG.

  FIG. 4A shows a state where the catheter 101 is attached to the MDU 102. In the drawing, reference numeral 400 denotes a base member of the MDU 102, which is a portion that comes into contact with a table, a floor, and the like in the operating room, and is also a portion whose position is fixed. Reference numerals 401 and 402 are support members that are provided on the base member 400 of the MDU 102 and fix and support the recesses 210 a of the unit connector 210 of the catheter 101. Reference numeral 403 denotes a slider portion that is movable with respect to the base member 400 in a direction indicated by an arrow 410 shown in the drawing. The movement of the slider portion 403 relative to the base member 400 is performed by driving a motor (not shown) provided in the MDU 102. Reference numeral 404 denotes a connector for maintaining the joint 211 of the catheter 101 in a connected state, rotating the drive shaft 203 in the catheter, and maintaining the imaging core and the operation control unit 103 in an electrically connected state. Part. The connector unit 404 is designated on the slider unit 403. This connector portion 404 is mounted on the slider portion 403. Therefore, when the slider portion 404 moves along the illustrated arrow 410, the inner tube 202 and the drive shaft 203 are pulled out with respect to the outer tube 201 as a result. Note that the structure of the MDU 102 is not the main point of the present application, and will not be described in detail.

  Now, in the state of FIG. 4A, it is assumed that the operator operates the MDU 102 to perform a pullback operation, and the slider portion 403 moves relative to the base member 400 by an arrow L illustrated in the figure by ΔL. FIG. 4B shows a state after the slider portion 403 has moved by ΔL.

  The unit connector 210 is supported by the base member 400 of the MDU 102, and the leaf spring pusher 215 is integrated with the unit connector 210. Therefore, even if the slider portion 403 moves, the position of the leaf spring pusher 215 does not change. It will be understood that when the slider portion 403 moves in the arrow direction 410 by ΔL, the inner tube 202 and the imaging core 230 are pulled out by at least ΔL with respect to the outer tube 201.

  On the other hand, the connector hubs 230 and 231 and the leaf spring guide 232 move in the direction of the arrow 410 by ΔL together with the slider portion 403. Since the slider member 250 is sandwiched between the connector hubs 230 and 231, the slider member 250 moves by ΔL toward the arrow 410 in the same manner as the connector hubs 230 and 231.

  However, the slider member 250 supports one end of the leaf spring 240 with the locking portion 251. Since the length of the leaf spring 240 is fixed and the other end is fixed to the leaf spring pusher 215, the slider member 250 moves in the downward direction indicated by the arrow 411 in the figure. It is clear that this amount of movement is equal to ΔL. In addition, since the slider member 250 moves in the direction of the arrow 411 shown in the drawing, the downward movement of the slider member 250 eventually acts to pull out the drive shaft 203 from the inner tube 202. Since the slider member 250 guides the drive shaft 203 on both side surfaces thereof, when paying attention only to ΔL movement of the slider member 250 in the direction of the arrow 411 in the figure, the pull-out amount (length) of the drive shaft 203 is 2 × ΔL.

  Therefore, if the movement of ΔL in the arrow 410 direction of the slider portion 403 of the MDU 102 is taken into account, the total length with which the drive shaft 203 is pulled out with respect to the outer tube 201 is 3 × ΔL.

  In summary, when the moving speed of the slider unit 403 of the MDU 102 during the pullback operation is V, the imaging core in the catheter 101 moves at a speed of 3V. In other words, when the maximum pullback length of the MDU 102 is Lcm, the imaging core housed in the catheter 101 of the embodiment has a moving range of 3 × L that is three times that. Therefore, the catheter 101 according to the embodiment can cope with a scan of lower limb blood vessels expected in the future.

  For the operation control device 103, when the catheter 101 of the embodiment is used, a parameter indicating that the imaging core is three times faster (or three times the moving distance) is set. Let's go.

As described above, according to the catheter 101 of the present embodiment, the moving range of the merging core becomes three times that of the conventional MDU 102 while using the MDU 102 so far. It is possible to obtain a tomographic image of the blood vessel over a double length. Therefore, although it is necessary to slightly modify parameters for reconstructing a vascular tomographic image in the system, it can be applied to diagnosis of lower limb blood vessels.

It should be noted that the member connecting the slide member 250 and the connector unit 210 (leaf spring pusher 232) can be kept bent in the orthogonal direction as shown in FIG. 2 and is made of a non-stretchable material. That's fine. Although it can be said that a metal leaf spring is preferable in this respect, other members may be substituted as long as they achieve an equivalent function.

  In the embodiment, the catheter applied to the diagnostic imaging apparatus using ultrasonic waves has been described as an example. However, the diagnostic imaging apparatus using optical interference or the catheter for diagnostic imaging apparatus using both ultrasonic and optical interference. It does not matter.

DESCRIPTION OF SYMBOLS 101 ... Catheter, 102 ... MDU, 103 ... Operation control apparatus, 201 ... Outer tube, 202 Inner tube, 203 ... Drive shaft, 210 ... Unit connector, 211 ... Joint, 215 ... Leaf spring pusher, 230, 231 ... Connector hub 232 ... leaf spring guide, 240 ... leaf spring, 250 ... slider member

Claims (4)

A diagnostic imaging catheter having an inner tube containing a drive shaft of an imaging core and an outer tube containing the inner tube,
A connector provided on the outer tube for fixing the drive shaft to the base portion of the motor drive unit of the diagnostic imaging apparatus in order to pull out the drive shaft from the outer tube together with the inner tube;
It is movable with the inner tube in the pulling direction of the inner tube with respect to the outer tube, and is movable in a direction orthogonal to the pulling direction, and by moving in the orthogonal direction, the imaging core A slider member that pushes the drive shaft;
A plate member having both ends supported by the connector and the slider member, bent in an orthogonal direction, and made of a non-stretchable material;
A catheter characterized by comprising:   The catheter according to claim 1, wherein the plate member is a metal leaf spring.   The catheter according to claim 1 or 2, wherein the imaging core accommodates an ultrasonic transmission / reception unit or an optical transmission / reception unit. The catheter according to any one of claims 1 to 3,
A motor drive unit for rotating the imaging core of the catheter and withdrawing the inner tube from the outer tube;
An image diagnostic apparatus comprising: means for generating a blood vessel cross-sectional image by the catheter based on a signal obtained from the catheter via the motor drive unit.

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