Ultrasound Catheter System

Abstract

[Problem] To provide an ultrasonic catheter and an ultrasonic catheter system with which an operator can easily specify the direction of an image acquired by a vibrator. [Solution] The present invention comprises: an outer sheath (20) in which an accommodation lumen (21) communicating from a base end to a tip is formed; a drive shaft (50) that can move along an axial center of the outer sheath (20), inside an inner sheath (30); a vibrator (41) that is disposed inside the accommodation lumen (21) and fixed to the tip of the drive shaft (50); and an X-ray impermeable tip marker (26) disposed on a tip portion of the outer sheath (20), wherein the tip marker (26) has a marker specifying part (27) extending along an axial center from a portion in a circumferential direction and a marker comparison part formed with a different length and / or a different arrangement from those of the marker specifying part (27) in a circumferential direction or a radial direction of the outer sheath (20).

Description

[Technical Field]

[0001] The present invention is a method for obtaining images by inserting the device into the lumen of the heart, blood vessels, etc. Super This invention relates to an ultrasonic catheter system. [Background technology]

[0002] When examining an affected area such as the heart or blood vessels, an ultrasound catheter is used that is inserted into the lumen of the living body and acquires images using ultrasound (see, for example, Patent Document 1). The ultrasound catheter has a transducer for transmitting and receiving ultrasound, a drive shaft for rotating the transducer, and a sheath that rotatably houses the transducer and drive shaft. The transducer is rotationally driven by the drive shaft within the sheath to transmit and receive ultrasound and acquire images of the inside of the living body. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2014 / 136137 Summary of the Invention [Problem to be solved by the invention]

[0004] A single transducer is placed and rotated, or multiple transducers are placed circumferentially to acquire a 360° image of a single circumferential plane. The transducer is moved axially, and images are superimposed to construct a three-dimensional image. Generally, the orientation of the ultrasound catheter and transducer inserted into the body is not controlled, making it difficult to determine the direction in which the transducer is pointing within the body. Therefore, in ultrasound images acquired, for example, inside the heart or abdomen, it is difficult to determine which direction is a specific direction in the patient's body (e.g., the ventral side).

[0005] The present invention has been made to solve the above-mentioned problems, and is a method for enabling an operator to easily identify the direction of an image acquired by a transducer. SuperAn object of the present invention is to provide an ultrasonic catheter system. [Means for solving the problem]

[0007] An ultrasound catheter system that achieves the above object is: The device comprises an outer sheath having a housing lumen formed therein that communicates from the base end to the tip end, a drive shaft that is movable within the outer sheath along the axis of the outer sheath, a transducer that is disposed within the housing lumen and fixed to the tip end of the drive shaft and is capable of transmitting and receiving ultrasound, and a radiopaque tip marker that is disposed at the tip end of the outer sheath, the tip marker having a marker specifying portion that extends along the axis in a portion of the circumferential direction, and a marker comparing portion that is formed in a different length and / or different arrangement from the marker specifying portion in the circumferential or radial direction of the outer sheath. The ultrasound catheter includes an ultrasound catheter, a drive unit for driving the ultrasound catheter, and a control device for controlling the drive unit, and the drive unit is controlled by the control device to move the drive shaft along the axis of the outer sheath. Department the control device has a control unit capable of controlling the moving unit, a display unit capable of receiving a signal from the control unit and displaying an image, and an input unit capable of receiving information as input from the outside and transmitting the information to the control unit, and the control unit receives a signal from the transducer via the drive unit to generate a two-dimensional ultrasound image and / or a three-dimensional image to be displayed on the display unit, and performs control to identify the direction of the marker identification part in the two-dimensional ultrasound image and / or the three-dimensional image automatically or by input from the input unit, and to display a mark indicating the direction of the marker identification part together with the two-dimensional ultrasound image and / or the three-dimensional image on the display unit. the control unit receives a signal from the transducer via the drive unit to generate a three-dimensional image of the biological tissue and displays it on the display unit, and performs control to display on the display unit a mark indicating the direction of the marker identification part identified from the two-dimensional ultrasound image together with the three-dimensional image of the biological tissue. It is characterized by the following. [Effects of the Invention]

[0008] The ultrasound catheter configured as described above can identify the direction in which the marker identifier placed on the outer sheath faces inside the body from relative position information of the marker identifier with respect to the marker comparison unit obtained by X-ray imaging performed from outside the body, and can also identify the direction of the marker identifier in the ultrasound image from position information of the marker identifier included in the ultrasound image obtained by the transducer in the accommodation lumen. Therefore, the ultrasound catheter allows the surgeon to easily identify a predetermined direction of the patient's body, for example, the ventral direction, in a two-dimensional ultrasound image obtained by the transducer moving within the outer sheath along the axis of the outer sheath and / or a three-dimensional image of the biological tissue generated based on the two-dimensional ultrasound image.

[0009] The ultrasound catheter system configured as described above can identify the direction of the marker identifier placed in the outer sheath from relative position information of the marker identifier with respect to the marker comparison unit obtained by X-ray imaging performed from outside the body, and can also obtain the position information of the marker identifier when acquiring an ultrasound image obtained by the transducer in the accommodation lumen. Therefore, the ultrasound catheter system allows the surgeon to easily identify the direction of the ultrasound image acquired by the transducer moving within the outer sheath along the axis of the outer sheath. The control unit receives a signal from the transducer via the drive unit to generate a three-dimensional image of the biological tissue and displays it on the display unit, and also displays a mark indicating the direction of the marker identification part identified from the two-dimensional ultrasound image on the display unit together with the three-dimensional image of the biological tissue. This allows the ultrasound catheter system to easily allow the surgeon to identify the direction of the three-dimensional image of the biological tissue acquired by the transducer rotating within the outer sheath.

[0010] The ultrasound catheter may further include a distal cap connected to the distal end of the outer sheath, the marker comparison unit being provided on the distal cap, and the marker identification unit extending proximally beyond the proximal end of the distal cap of the outer sheath. This allows the distal marker and the distal cap to identify the direction of the ultrasound image within the body. Furthermore, since the marker comparison unit is unlikely to enter the observable range of the transducer, it is possible to prevent the ultrasound image obtained by the transducer from having a range that cannot be observed by the marker comparison unit.

[0011] The width of the marker identification portion in the circumferential direction of the outer sheath may be 0.5 to 1.5 mm, which allows the marker identification portion to be stably identified by X-ray photography and also stably identified by ultrasound images obtained by a vibrator.

[0012] The outer sheath is One bend or Axial direction each other At least in different positions 2 The ultrasound catheter may have two bends, and a second radiopaque marker may be placed on the outer sheath at the bend or at a position adjacent to the bend. This allows the ultrasound catheter to freely adjust the distance and angle of the transducer in the accommodation lumen relative to the observation target while grasping the position of the bend by rotating the outer sheath while observing the second marker by X-ray photography. Therefore, even when the ultrasound catheter is inserted into a wide lumen, it is possible to obtain highly accurate images of the observation target.

[0013] The width of the second marker in the circumferential direction of the outer sheath may be 0.2 to 0.5 mm, which has little effect on the ultrasound image, thereby preventing the ultrasound image obtained by the transducer from having an area that cannot be observed due to the second marker.

[0014] The ultrasonic catheter may have a covering tube that covers the tip marker disposed on the outer surface of the outer sheath, and at least a portion of the covering tube may be fixed to the outer sheath, thereby preventing the marker identifying portion from being exposed to the outside and preventing the marker identifying portion from rubbing against the inner wall of the blood vessel, damaging the inner wall of the blood vessel, or from falling off.

[0015] The surface of the marker identifier facing the transducer and the ultrasonic irradiation surface of the transducer may be parallel to the axis of the outer sheath, which makes it easier to identify the direction of the marker identifier in an ultrasound image obtained from the transducer.

[0016] The surface of the marker identifier facing the axis of the outer sheath may be roughened. This allows for greater reflection of ultrasound waves and a clearer, stronger white color in the ultrasound image. Therefore, the white color formed by the roughened surface makes it easier to identify the direction of the marker identifier in the ultrasound image obtained from the transducer.

[0018] The control unit may generate a 3D model image showing a simplified shape of the human body on a 3D coordinate system different from that of the 3D image of the biological tissue, and display the 3D image of the biological tissue and the 3D model image on the display unit in synchronized orientations. This allows the surgeon to observe the 3D image of the biological tissue while comparing it with the 3D model image, thereby making it possible to easily identify the orientation of the 3D image of the biological tissue within the body.

[0019] When the control unit receives information for changing the orientation of the 3D image of the biological tissue or the 3D model image on the display unit from the input unit, the control unit may change the orientation of the 3D image of the biological tissue and the 3D model image synchronously and display them on the display unit. This allows the surgeon to adjust the orientation of the 3D image of the biological tissue and the 3D model image to an orientation that is easy to view while synchronizing them, thereby making it easy to identify the orientation of the 3D image of the biological tissue within the body. [Brief explanation of the drawings]

[0020] [Figure 1] FIG. 1 is a plan view showing an ultrasound catheter. [Figure 2] 1A and 1B are cross-sectional views of a transducer of an ultrasound catheter, where (A) shows the tip end and (B) shows the base end. [Figure 3] 1 is a schematic diagram illustrating an ultrasound catheter system including an ultrasound catheter. [Figure 4] 1A and 1B are diagrams showing the marker identification section and the marker comparison section, in which (A) is a diagram showing the definition of angles as viewed from the tip side, and (B) is a side view at each angle. [Figure 5] FIG. 2 is a block diagram showing a control device. [Figure 6] 1 is a schematic diagram showing an example of use of an ultrasound catheter system according to an embodiment of the present invention. [Figure 7] Schematic diagrams showing two-dimensional ultrasound images generated by an ultrasound catheter system, where (A) shows the state before the display angle is changed, and (B) shows the state after the display angle is changed. [Figure 8] FIG. 1 is a diagram showing a three-dimensional image of biological tissue generated by an ultrasound catheter system and displayed on a display unit. [Figure 9] 10A and 10B are diagrams showing the state in which the angle of a three-dimensional image of biological tissue generated by the ultrasound catheter system and displayed on the display unit is changed. [Figure 10] 10 is a flowchart showing a control flow in a control unit. [Figure 11]10A to 10C are diagrams showing modified examples of an ultrasound catheter, where (A) shows a first modified example, (B) shows a second modified example, and (C) shows a third modified example. [Figure 12] 10A and 10B are diagrams showing modified examples of an ultrasonic catheter, where (A) shows a fourth modified example and (B) shows a fifth modified example. [Figure 13] 10A to 10C are diagrams showing modified examples of an ultrasonic catheter, where (A) shows a sixth modified example, (B) shows a seventh modified example, and (C) shows an eighth modified example. [Figure 14] 10A and 10B are diagrams showing modified examples of an ultrasonic catheter, where (A) shows a ninth modified example and (B) shows a tenth modified example. [Figure 15] 10A and 10B are diagrams showing modified examples of an ultrasonic catheter, where (A) shows an eleventh modified example and (B) shows a twelfth modified example. [Figure 16] FIG. 13 is a cross-sectional view showing a thirteenth modified example of the ultrasound catheter. DETAILED DESCRIPTION OF THE INVENTION

[0021] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the dimensional proportions in the drawings may be exaggerated for the sake of explanation and may differ from the actual proportions. In this specification, the side that is inserted into the living body will be referred to as the "distal side" and the side that is operated will be referred to as the "proximal side."

[0022] The ultrasound catheter system 1 according to this embodiment is a system that acquires ultrasound images transvascularly using an ultrasound catheter 10 that is inserted primarily into the heart or blood vessels, and displays the obtained ultrasound images so that their directions within the body can be easily identified, as shown in Fig. 3. The ultrasound catheter system 1 includes the ultrasound catheter 10, a drive unit 80, a pump device 90, and a control device 100.

[0023] 1 and 2, the ultrasound catheter 10 includes an outer sheath 20, a tip marker 26, a second marker 28, an inner sheath 30, a transducer unit 40, and a drive shaft 50. The ultrasound catheter 10 further includes a first housing 60 and a second housing 70.

[0024] The outer sheath 20 is a tubular body to be inserted into a cavity in the body. From the base end to the tip, the outer sheath 20 comprises a base end tubular portion 23, a bent portion 24, and a tip end tubular portion 25. A housing lumen 21 that communicates from the base end to the tip is formed inside the base end tubular portion 23, the bent portion 24, and the tip end tubular portion 25.

[0025] The base-side tubular portion 23 is a tubular body having a substantially linear axis. The base end of the base-side tubular portion 23 is fixed to the first housing 60. The axis of at least the tip end of the base-side tubular portion 23 is located on the linear reference line X. The bent portion 24 is a tubular body located on the tip side of the base-side tubular portion 23 and having a bent axis. The tip end tubular portion 25 is a tubular body located on the tip side of the bent portion 24 and having a linear axis. The tip end of the tip end tubular portion 25 is fixed to the tip cap 22.

[0026] The bending angle θ of the bending portion 24 is not particularly limited, but is preferably 10° to 40°. If the bending angle θ is too small, the offset amount L2 of the distal end of the outer sheath 20 relative to the proximal end becomes small. The offset amount L2 is the length from the reference line X to the axial center of the portion of the outer sheath 20 distal to the bending portion 24 that is farthest from the reference line X in a direction perpendicular to the reference line X. If the bending angle θ is too large, the rotation and axial movement of the drive shaft 50, which rotates and moves axially while being bent inside the bending portion 24, are likely to be hindered. In contrast, by setting the bending angle θ to an appropriate value, it becomes easier to set the offset amount L2 of the outer sheath 20 to a desired value while stably maintaining the rotation and axial movement of the drive shaft 50.

[0027] The distal end length L1, which is the length along the reference line X from the boundary between the proximal tubular portion 23 and the bending portion 24 to the tip of the outer sheath 20, is not particularly limited, but is preferably 20 to 150 mm. Therefore, the length along the reference line X of the offset portion (the portion whose axis is shifted from the reference line X in a direction perpendicular to the reference line X) distal to the bending portion 24 of the outer sheath 20 can be appropriately set for use in the heart or blood vessels having a wide lumen. Furthermore, if the distal end length L1 is too short, the offset amount L2 of the distal end of the outer sheath 20 relative to the proximal end tends to be small. If the distal end length L1 is too long, the offset amount L2 of the distal end of the outer sheath 20 relative to the proximal end tends to be large. On the other hand, an appropriate distal end length L1 makes it easier to set the offset amount L2 of the outer sheath 20 to a desirable value.

[0028] The offset amount L2 is not particularly limited, but is preferably 5 to 30 mm. When the offset amount L2 has an appropriate size, it becomes easy to bring the outer sheath 20 close to the observation site inside the heart or blood vessels which have a wide lumen.

[0029] The outer sheath 20 accommodates a transducer unit 40, an inner sheath 30, and a drive shaft 50 in a housing lumen 21. The transducer unit 40, the inner sheath 30, and the drive shaft 50 in the outer sheath 20 are movable within the housing lumen 21 along the axis of the outer sheath 20. Furthermore, the transducer unit 40 and the drive shaft 50 in the outer sheath 20 are rotatable within the outer sheath 20. The outer sheath 20 is a cylindrical body whose proximal end is open and whose distal end is closed by a distal cap 22. The proximal end of a proximal tubular portion 23 forming the proximal end of the outer sheath 20 is fixed to the first housing 60. The distal end of a distal tubular portion 25 forming the distal end of the outer sheath 20 is fixed to the distal cap 22, which is part of the distal marker 26. The proximal end of the outer sheath 20 may be provided with a reinforcing member such as a braided wire.

[0030] In this embodiment, one bent portion 24 is provided, but it may be omitted, or two or more bent portions may be provided.

[0031] The distal marker 26 is fixed to a portion of the circumferential direction of the distal end of the outer sheath 20. The distal marker 26 is formed containing a radiopaque material. The distal marker 26 has a distal cap 22 and a marker identifying portion 27 that extends linearly along the axis of the outer sheath 20.

[0032] The tip cap 22 is a member that closes the opening on the tip side of the outer sheath 20. The tip cap 22 is formed containing a radiopaque material. The tip cap 22 may have a guidewire lumen formed therein. In this case, the ultrasound catheter 10 can be a rapid exchange type having a guidewire lumen at the tip. As will be described later, the tip cap 22 functions as a marker comparison unit that compares with the marker identification unit 27. The tip cap 22 may also have an opening that allows fluid inside the outer sheath 20 to be released to the outside. The tip cap 22 may not contain a radiopaque material and may not function as a marker.

[0033] At least a portion of the marker-identifying portion 27 is disposed closer to the base end than the distal cap 22. In this embodiment, the distal end of the marker-identifying portion 27 is disposed at approximately the same position as the proximal end of the distal cap 22 in the axial direction of the outer sheath 20. The marker-identifying portion 27 is disposed on the outer peripheral surface, inner peripheral surface, or inside the material of the outer sheath 20.

[0034] The marker identifying portion 27 is formed to be shorter in the circumferential direction and shorter in the radial direction than the tip cap 22, which is the marker comparison portion. The width W1 of the marker identifying portion 27 in the circumferential direction of the outer sheath 20 is not particularly limited, but is preferably, for example, about 0.5 to 0.8 mm. This allows the marker identifying portion 27 to be identified by X-ray photography and also by two-dimensional or three-dimensional ultrasound images obtained by the transducer 41. The marker identifying portion 27 extends a predetermined length in the axial direction of the outer sheath 20. Therefore, a range in which the marker identifying portion 27 can be observed by the transducer 41 is secured in the axial direction of the outer sheath 20, and therefore the marker identifying portion 27 can be reliably identified from ultrasound images obtained by the transducer 41.

[0035] Because the marker identifying portion 27 is fixed to a portion of the circumference of the outer sheath 20, its position in the circumference direction changes as the outer sheath 20 rotates around its axis. For example, as shown in FIG. 4(A), the marker identifying portion 27 can be positioned at any angle α clockwise from the reference position of 0° as viewed from the distal end. The shapes of the distal end cap 22 (marker comparison portion) and the marker identifying portion 27 observed by X-ray imaging from one direction D on the radial outside of the outer sheath 20 change depending on the angle α, as shown in FIG. 4(B). In this case, the shape of the distal end cap 22 (marker comparison portion), which has a shape that is not biased in the circumferential direction, remains almost unchanged, while the shape of the marker identifying portion 27, which is positioned only in a portion of the circumference direction, changes. Therefore, the surgeon can determine the direction in which the marker identifying portion 27 of the outer sheath 20 faces by observing the relative position of the marker identifying portion 27 with respect to the marker comparison portion from an image obtained by X-ray imaging. It is difficult to determine the positional relationship of components in the depth direction from only images obtained by X-ray photography. For example, the image at 0° and the image at 180° are similar. Similarly, the image at 60° and the image at 120°, and the image at 240° and the image at 300° are similar. However, because the surgeon can observe X-ray images while rotating the outer sheath 20 in the circumferential direction, the depth direction position of the angle α can also be determined by observing X-ray images within a predetermined angle range including the desired angle α. Therefore, the surgeon can distinguish between, for example, X-ray images at 0° and 180°, X-ray images at 60° and 120°, and X-ray images at 240° and 300°, which are similar images.

[0036] The second marker 28 is arranged in the axial direction of the outer sheath 20 at the same position as or adjacent to the bending portion 24. The second marker 28 is fixed to a portion of the outer sheath 20 in the circumferential direction. The width W2 of the second marker 28 in the circumferential direction is not particularly limited, but is preferably 0.2 to 0.5 mm, for example. As a result, the second marker 28 is sufficiently thin so that it does not interfere with the acquisition of an ultrasound image from inside the outer sheath 20 through the outer sheath 20.

[0037] 1 and 2, the inner sheath 30 is a cylindrical body, a portion of its distal end being inserted into the outer sheath 20. The distal end portion of the inner sheath 30 is housed inside the outer sheath 20 so as to be movable along the axis of the outer sheath 20. The proximal end portion of the inner sheath 30 is led out from the outer sheath 20 and the first housing 60 toward the proximal end, and is fixed to the second housing 70.

[0038] The inner sheath 30 rotatably houses the drive shaft 50. The distal end of the inner sheath 30 is located on the proximal end side of the transducer unit 40 and in close proximity to the transducer unit 40. The inner sheath 30 is disposed between the inner circumferential surface of the outer sheath 20 and the outer circumferential surface of the drive shaft 50, and stabilizes the rotational and axial movements of the drive shaft 50.

[0039] The transducer unit 40 transmits and receives ultrasound waves toward biological tissue inside the body. The transducer unit 40 includes a transducer 41 that transmits and receives ultrasound waves, and a transducer holder 42 on which the transducer 41 is disposed and which is fixed to the drive shaft 50. The transducer unit 40 is movable within the accommodation lumen 21 of the outer sheath 20, over the bending portion 24, in the axial direction of the outer sheath 20. The transducer unit 40 is also rotatable within the accommodation lumen 21 around the axial center.

[0040] The constituent materials of the outer sheath 20 and the inner sheath 30 are not particularly limited as long as they are flexible and have a certain degree of strength, but suitable examples include polyolefins such as polyethylene and polypropylene, polyesters such as polyamide and polyethylene terephthalate, fluorine-based polymers such as PTFE (polytetrafluoroethylene) and ETFE (ethylene-tetrafluoroethylene copolymer), PEEK (polyether ether ketone), and polyimides.

[0041] The tip cap 22 may be made of a material that is opaque to radioactivity, such as barium sulfate, bismuth oxide, tungsten, gold, platinum, or tantalum, that can be used for the outer sheath 20 and the inner sheath 30. Examples of the opaque material include barium sulfate, bismuth oxide, tungsten, gold, platinum, and tantalum.

[0042] The drive shaft 50 transmits the rotational force and axial movement force acting from the drive unit 80 (see FIG. 3) to the transducer unit 40. The drive shaft 50 includes a flexible distal drive shaft 51 that passes through the inner sheath 30 and a connecting pipe 52 that is fixed to the proximal end of the distal drive shaft 51. The distal end of the distal drive shaft 51 is fixed to the transducer holding portion 42. The distal drive shaft 51 is formed of a multi-layered coiled tube, such as a three-layered coil whose winding direction alternates between right and left. The connecting pipe 52 is, for example, a metal circular tube. The proximal end of the connecting pipe 52 is fixed to a rotor 77 that rotates inside the second housing 70.

[0043] The drive shaft 50 transmits rotational power to rotate the transducer unit 40, allowing 360-degree observation of the internal structure of tissue from blood vessels and cardiac chambers. The drive shaft 50 is movable within the accommodation lumen 21 of the outer sheath 20 along the axis of the outer sheath 20.

[0044] The signal line 53 is disposed so as to pass through the inside of the drive shaft 50. The signal line 53 transmits a signal transmitted from the rotor 77 to the transducer unit 40. The signal line 53 also transmits a signal detected by the transducer unit 40 to the drive unit 80 via the rotor 77.

[0045] The proximal end of the outer sheath 20 is fixed in a liquid-tight manner to the first housing 60. The first housing 60 includes a first port 62 that communicates with the inner cavity of the outer sheath 20, and a first sealing portion 64.

[0046] The first hollow portion 61 communicates with the first port 62 and the housing lumen 21 of the outer sheath 20. The inner sheath 30 and the drive shaft 50, which extend from the outer sheath 20 toward the proximal end, pass through the first hollow portion 61. The first housing proximal end portion 63 has a through-hole that communicates with the first hollow portion 61 and is located on the proximal side of the first hollow portion 61. A first sealing portion 64 is disposed in the through-hole of the first housing proximal end portion 63. The inner sheath 30 and the drive shaft 50 pass through the first sealing portion 64. The first sealing portion 64 is in liquid-tight contact with the first housing proximal end portion 63. The first sealing portion 64 is in slidable and rotatable contact with the outer peripheral surface of the inner sheath 30 along the axis of the inner sheath 30. The first sealing portion 64 is not particularly limited as long as it is slidable along the outer peripheral surface of the inner sheath 30, and may be, for example, an O-ring or a cross-cut valve body.

[0047] The first housing 60 is rotatably supported by a tip end support portion 83 of the drive unit 80, which will be described later.

[0048] The second housing 70 is disposed on the proximal side of the first housing 60. The proximal end of the inner sheath 30, which is led out from the first housing 60 toward the proximal side, is fixed liquid-tight to the second housing 70. The second housing 70 is movable toward and away from the first housing 60 along the axis of the inner sheath 30.

[0049] The second housing 70 includes a second hollow portion 71 that communicates with the lumen of the inner sheath 30, a second port 72, a second housing proximal end portion 73, and a second sealing portion 74. The second housing 70 further includes a joint 75, a connector 76, and a rotor 77.

[0050] The second hollow portion 71 communicates the second port 72 with the lumen of the inner sheath 30. The drive shaft 50, which extends from the inner sheath 30 toward the proximal end, passes through the second hollow portion 71. The second housing proximal end portion 73 has a through-hole that communicates with the second hollow portion 71 and is located on the proximal end side of the second hollow portion 71. A second sealing portion 74 is disposed in the through-hole of the second housing proximal end portion 73. The connection pipe 52 of the drive shaft 50 passes through the second sealing portion 74. The second sealing portion 74 slidably contacts the outer peripheral surface of the connection pipe 52 in the rotational direction of the connection pipe 52. The second sealing portion 74 slidably seals the gap between the second housing proximal end portion 73 and the drive shaft 50. The second sealing portion 74 is not particularly limited as long as it is slidable against the outer peripheral surface of the drive shaft 50, but it may be, for example, an O-ring. The second port 72 is an opening to which a tube or the like can be connected for injecting or discharging a fluid such as physiological saline solution.

[0051] The joint 75 is fixed to the base end side of the second housing base end portion 73. The joint 75 has a joint opening 751 on the base end side, and a connector 76 and a rotor 77 are disposed inside. The connector 76 is connectable to a drive-side connector 811 of the drive unit 80 (see FIG. 3 ) that enters through the joint opening 751. The connector 76 is mechanically and electrically connected to the drive-side connector 811. A signal line 53 that passes through the inside of the connection pipe 52 is connected to the connector 76. Therefore, the connector 76 is connected to the transducer unit 40 via the signal line 53.

[0052] The rotor 77 has a connecting pipe 52 fixed thereto. The rotor 77 rotates integrally with the connector 76 inside the joint 75. When the rotor 77 rotates, the drive shaft 50 fixed to the rotor 77 also rotates. The rotor 77 is sandwiched between the joint 75 and the second housing base end 73, restricting its axial movement. The rotor 77 is rotatable inside the second housing 70 and is movable along the axis together with the second housing 70. The transducer unit 40 outputs ultrasonic waves in response to signals received via the connector 76 and the signal line 53. The transducer unit 40 also receives reflected waves, converts them into signals, and transmits the signals to the drive unit 80 via the signal line 53 and the connector 76. The drive unit 80 performs appropriate processing on the received signals and displays them as images.

[0053] The constituent materials of the first housing 60 and the second housing 70 are not particularly limited as long as they have a certain degree of strength, but for example, polycarbonate, polyamide, polysulfone, polyarylate, methacrylate-butylene-styrene copolymer, etc. are suitably used.

[0054] 3, the drive unit 80 is provided with a drive section 81, which incorporates a drive source such as a motor and rotates the drive shaft 50, a moving section 82 which moves the drive section 81 in the axial direction, and a distal end support section 83 which rotatably supports the engagement section 65 of the ultrasound catheter 10, on a base 85. The drive unit 80 is connected to a control device 100 which controls the drive section 81 and the moving section 82. The drive unit 80 also relays signals between the control device 100 and the transducer unit 40.

[0055] The moving unit 82 can grip and fix the driving unit 81. The moving unit 82 is a feed mechanism driven by a driving source such as a motor. The moving unit 82 moves the fixed driving unit 81 back and forth along a groove rail 86 on a base 85.

[0056] The driving unit 81 includes a driving connector 811 that can be connected to the connector 76 of the ultrasonic catheter 10, and a base-end support unit 812 that can be connected to the joint 75 of the ultrasonic catheter 10. When the connector 76 is connected to the driving connector 811, the driving unit 81 can send and receive signals to and from the transducer unit 40, and can rotate the drive shaft 50.

[0057] Ultrasound scanning in the ultrasound catheter 10 is performed by transmitting the rotational motion of the drive unit 81 to the drive shaft 50, thereby rotating the transducer unit 40 fixed to the tip of the drive shaft 50. This allows ultrasound waves transmitted and received by the transducer 41 to scan in a substantially radial direction. Furthermore, the drive shaft 50 can be pulled toward the base end by the moving unit 82. This allows the transducer 41 to move toward the base end while rotating. Therefore, 360° cross-sectional images of the surrounding tissue of a blood vessel or cardiac chamber can be obtained by scanning up to any position along the axis of the outer sheath 20.

[0058] The pump device 90 can circulate fluid to the ultrasound catheter 10. The pump device 90 includes a supply tube 91 that supplies fluid and a recovery tube 92 that recovers the fluid. The supply tube 91 is connected to the second port 72. The recovery tube 92 is connected to the first port 62. The pump mechanism of the pump device 90 is not particularly limited, and may be, for example, a peristaltic pump, a centrifugal pump, or a diaphragm pump. The pump device 90 may be a non-circulating type. In this case, the first port 62 is connected to a tube that leads to a waste container. Alternatively, the pump device 90 may not be provided.

[0059] As shown in Figures 3 and 5, the control device 100 is a device that controls the operation of the drive unit 80 of the ultrasound catheter system 1, conversion of signals obtained by the ultrasound catheter 10 into image data, display of the image data on the display unit 103, input of instructions from the surgeon, etc. The control device 100 has a control unit 101, an input unit 102, and a display unit 103. The control device 100 may also have other functions. The control device 100 is, for example, a computer.

[0060] The control unit 101 includes a memory circuit and an arithmetic circuit. The memory circuit stores programs and various parameters. The arithmetic circuit is, for example, a CPU (Central Processing Unit), and can read the programs and various parameters from the memory circuit and perform arithmetic processing.

[0061] The control unit 101 can control the operation of the drive unit 81 and the moving unit 82 of the drive unit 80. In addition, the control unit 101 can convert an electrical signal obtained from the transducer 41 of the ultrasound catheter 10 via the drive unit 80 into image data that can be displayed as an image on the display unit 103, and transmit it to the display unit 103 for display. In addition, the control unit 101 can correct and change the image data to be displayed on the display unit 103 based on an instruction signal input from the input unit 102 by the surgeon, and display it on the display unit 103.

[0062] The display unit 103 is a monitor capable of displaying visually recognizable images. The display unit 103 is connected to the control unit 101 so as to receive signals including image data from the control unit 101. The images displayed include two-dimensional ultrasound images acquired by the ultrasound catheter 10, three-dimensional images of biological tissue generated based on the two-dimensional ultrasound images, and three-dimensional model images that simply represent the entire human body. The display unit 103 displays images based on the image data received from the control unit 101.

[0063] The input unit 102 includes, for example, a keyboard, a mouse, a microphone, a media reading device, etc. The input unit 102 is connected to the control unit 101 so as to be able to transmit information input by, for example, an operator.

[0064] Next, a method of using the ultrasound catheter system 1 according to this embodiment will be described with reference to the flowchart shown in Fig. 10. Here, as shown in Fig. 6, a procedure in which the ultrasound catheter 10 is inserted from the femoral vein into the right atrium HRa and the atrial septum HA is punctured will be described as an example.

[0065] First, before inserting the ultrasound catheter 10 into a blood vessel, the supply tube 91 of the pump device 90 is connected to the second port 72, and the recovery tube 92 is connected to the first port 62, as shown in FIG.

[0066] Next, the pump device 90 is driven to inject, for example, saline solution into the second hollow portion 71 from the second port 72 of the second housing 70. As a result, the saline solution flows into the gap between the drive shaft 50 and the inner sheath 30, as shown by the dashed line in FIG. 2 , moves toward the distal end, and reaches a position distal to the inner sheath 30. This fills the space between the outer sheath 20 and the transducer unit 40 with saline solution. Next, the saline solution flows from the distal end of the inner sheath 30 into the gap between the outer sheath 20 and the inner sheath 30 and moves toward the proximal end. Thereafter, the saline solution is discharged from the first port 62 of the first housing 60. This removes air from inside the ultrasound catheter 10, and the area around the transducer unit 40 is filled with saline solution. Thereafter, the pump device 90 continues or stops the circulation of saline solution, and the ultrasound catheter 10 is inserted into a biological lumen. Instead of using a pump device, the physiological saline solution may be manually filled using a syringe.

[0067] 3, the first housing 60 of the ultrasound catheter 10 is connected to the distal support portion 83 of the drive unit 80. Next, the joint 75 of the ultrasound catheter 10 is connected to the proximal support portion 812 of the drive portion 81. This enables transmission and reception of signals between the transducer unit 40 and the drive unit 80. Furthermore, the drive shaft 50 becomes rotatable about its axis and movable along its axis by the drive portion 81 and the moving portion 82.

[0068] Next, the surgeon percutaneously inserts the ultrasound catheter 10 into the femoral vein. Then, as shown in Figure 6, the surgeon pushes the ultrasound catheter 10 inserted into the blood vessel under X-ray observation until it reaches the right atrium HRa via the inferior vena cava IV. The surgeon positions the tip of the ultrasound catheter 10 at a position beyond the fossa ovalis Fo, which is the object of observation (closer to the superior vena cava than the fossa ovalis Fo). The surgeon also percutaneously inserts a sheath 200 into the femoral vein, and reaches it through the inferior vena cava IV to the right atrium HRa.

[0069] Next, the surgeon adjusts the overall position of the ultrasound catheter 10 so that the second marker 28 on the outer sheath 20 is located near the fossa ovalis Fo. Because the second marker 28 is provided at the bending portion 24, the surgeon can easily position the portion of the outer sheath 20 where the second marker 28 is to be provided at a desired position by observing an X-ray image. Furthermore, because the ultrasound catheter 10 has the bending portion 24, the surgeon can easily adjust the position of the transducer 41 to any desired distance and angle for observing the fossa ovalis Fo by rotating the outer sheath 20.

[0070] The surgeon observes the distal end cap 22 and the distal end marker 26 in an X-ray image and adjusts the marker identification portion 27 so that it faces, for example, toward the patient's ventral side. That is, the surgeon adjusts the position of the outer sheath 20 so that the shapes of the marker comparison portion and the marker identification portion 27 observed in the X-ray image are substantially T-shaped, with the marker identification portion 27 positioned in the direction of angle α = 0° in Figure 4(B). Note that, as long as it is possible to identify the relationship between the marker identification portion 27 and the orientation of the body, the direction in which the marker identification portion 27 faces is not limited to the ventral side and may be, for example, toward the back.

[0071] Next, the ultrasound catheter 10 is connected to the drive unit 80, and the second housing 70 is brought closest to the first housing 60, as shown in FIGS. 1 and 2. This positions the transducer 41 near the tip of the outer sheath 20. Therefore, the transducer 41 is positioned within a range where the marker identification unit 27 can be observed by rotating it. The transducer 41 may be positioned near the tip of the outer sheath 20 in advance.

[0072] Next, the surgeon operates the input unit 102 to acquire image data from the transducer 41 and display it on the display unit 103. The control device 100 activates the drive unit 80 to rotate the drive shaft 50 based on the instruction signal received from the input unit 102. As a result, the transducer 41 rotates 360° or more, transmitting ultrasonic waves along the XY plane perpendicular to the axis of the outer sheath 20 while receiving reflected waves (step S01). The control device 100 receives the signal via the drive unit 80, and generates a two-dimensional ultrasonic image of the XY plane perpendicular to the axis of the outer sheath 20 (step S02), as shown in the schematic diagram of FIG. 7(A), and displays it on the display unit 103 (step S03). In the two-dimensional ultrasound image, the biological tissue T1 receiving ultrasound is represented by a strong white color, indicating that the ultrasound has been strongly reflected. The marker identification portion 27 is represented by a white acoustic artifact Ar extending radially from the outer circumferential surface of the ultrasound catheter 10. The biological tissue T2 within the area hidden from the ultrasound by the marker identification portion 27 is represented by a strong black color, indicating that the ultrasound has hardly been reflected. The surgeon observes the two-dimensional ultrasound image displayed on the display unit 103 and identifies the direction represented by the white acoustic artifact Ar caused by the presence of the marker identification portion 27 or the strong black color, indicating that the ultrasound has hardly been reflected. Next, while observing the display unit 103, the surgeon operates the input unit 102 to mark and register a mark M in the direction in which the marker identification portion 27 is located. The surgeon can move the mark M on the screen of the display unit 103 using, for example, a keyboard or mouse, to mark the mark M in the direction in which the marker identification portion 27 is located. The control device 100 stores the direction in which the marker identifying unit 27 exists based on information input by the surgeon (step S04), and can display a mark M (for example, a triangle, an arrow, or the like) on the display unit 103 (step S05). By identifying and storing the direction in which the marker identifying unit 27 exists on the XY plane, the control unit 101 can identify the orientation of the marker identifying unit 27 in the obtained ultrasound image (ventral side in this embodiment) even if the transducer 41 is subsequently moved in the axial direction and placed in a position where the marker identifying unit 27 cannot be observed.The control unit 101 may automatically identify the direction in which the marker identifying unit 27 of the two-dimensional ultrasound image on the XY plane is located by image analysis, without relying on the input of the mark M by the operator.

[0073] Next, the surgeon operates the input unit 102 to rotate the two-dimensional ultrasound image displayed on the display unit 103 together with the mark M around the axis, as shown in FIG. 7(B), and adjusts it so that the mark M is, for example, upward (12 o'clock direction). The control unit 101 displays the rotated two-dimensional ultrasound image on the display unit 103 based on the instruction information input to the input unit 102 (step S06). Note that the control unit 101 may automatically rotate the two-dimensional ultrasound image displayed on the display unit 103 around the axis so that the direction in which the mark M is added is 12 o'clock direction, without relying on an instruction from the surgeon. This step is an optional step, as it is a step for making it easier for the surgeon to imagine the direction in which the marker identification unit 27 is located, and may not be necessary.

[0074] Next, the surgeon operates the input unit 102 to start acquisition of a three-dimensional image U1 of the biological tissue by the transducer 41, as shown in FIG. 8. The control unit 101 activates the drive unit 80 based on the instruction information input to the input unit 102, and performs pullback while rotating the drive shaft 50. The control unit 101 stacks multiple two-dimensional ultrasound images obtained from the transducer 41 in the pullback direction to generate a three-dimensional image U1 of the biological tissue (step S07), and displays the three-dimensional image U1 on the display unit 103 (step S08). At this time, because the X-axis and Y-axis directions of each two-dimensional ultrasound image are the same, the direction of the marker identifier 27 identified from the two-dimensional ultrasound image (or the three-dimensional image of the biological tissue) before the pullback can be applied to three-dimensional coordinates as the direction of the marker identifier 27 in the three-dimensional image U1 of the biological tissue obtained during the pullback operation. Therefore, the control unit 101 can add a mark M indicating the direction of the marker identification unit 27 to a three-dimensional image U1 of biological tissue of a tissue (for example, the vicinity of the fossa ovalis Fo of the atrial septum HA) acquired in real time and display it on the display unit 103. The range hidden from the ultrasound by the marker identification unit 27 is the area at the bottom right of the three-dimensional image U1 shown in FIG. 8 where the wall of the biological tissue is discontinued.

[0075] Furthermore, the control unit 101 generates a simplified 3D model image U2 of the human body on three-dimensional coordinates different from the 3D coordinates of the real-time 3D image U1 of the biological tissue (step S09). The control unit 101 assigns a mark M to the direction of the marker identification unit 27 (ventral side in this embodiment) determined by X-ray imaging, and displays it on the display unit 103 together with the 3D model image U2. The position of the mark M to be assigned to the 3D model image U2 is input from the input unit 102. The control unit 101 then synchronizes the orientation of the 3D image U1 of the biological tissue with the orientation of the 3D model image U2 and displays them on the display unit 103 (step S10). That is, the control unit 101 displays them on the display unit 103 so that the orientation of the mark M in the 3D image U1 of the biological tissue and the orientation of the mark in the 3D model image U2 coincide with each other. When the surgeon rotates the real-time 3D image U1 (or 3D model image U2) of the biological tissue on the display unit 103 in any direction and at any angle using the input unit 102, the control unit 101 synchronously rotates both the 3D image U1 of the biological tissue and the 3D model image U2 and displays them on the display unit 103 (step S11), as shown in FIG. 9. This allows the surgeon to observe the real-time 3D image U1 of the biological tissue while comparing it with the 3D model image U2, making it easy to identify the direction of the 3D image U1 of the biological tissue within the body. Note that the 3D image U1 shown in FIG. 9 displays the area closer to the operator (proximal end) than the marker identification unit 27, and therefore does not display the area hidden from ultrasound by the marker identification unit 27.

[0076] Next, as shown in FIG. 6, the surgeon brings the septal puncture needle 201 into the right atrium HRa through the sheath 200. Next, the surgeon confirms that the septal puncture needle 201 is heading toward the fossa ovalis Fo while observing the real-time 3D tissue image U1 of the living tissue captured by the ultrasound catheter 10. Thereafter, the surgeon punctures the fossa ovalis Fo with the septal puncture needle 201 while observing the real-time 3D tissue image U1 of the living tissue. This reliably prevents the septal puncture needle 201 from puncturing any part other than the fossa ovalis Fo. Thereafter, the surgeon removes the septal puncture needle 201, the sheath 200, and the ultrasound catheter 10, completing the procedure.

[0077] As described above, the ultrasound catheter 10 of this embodiment comprises an outer sheath 20 having a storage lumen 21 formed therein that communicates from the base end to the tip, a drive shaft 50 that is movable within the outer sheath 20 along the axial direction of the outer sheath 20, a transducer 41 that is disposed within the storage lumen 21 and fixed to the tip of the drive shaft 50 and is capable of transmitting and receiving ultrasound, and a radiopaque tip marker 26 that is disposed at the tip of the outer sheath 20, and the tip marker 26 has a marker identification portion 27 that extends along the axis in part of the circumferential direction, and a marker comparison portion that is formed in a different length and / or different arrangement from the marker identification portion 27 in the circumferential or radial direction of the outer sheath 20.

[0078] The ultrasound catheter 10 configured as described above can identify the direction in which the marker identifying unit 27 disposed in the outer sheath 20 faces within the body from relative position information of the marker identifying unit 27 with respect to the tip cap 22, which is a marker comparison unit, obtained by X-ray imaging performed from outside the body, and can also identify the direction of the marker identifying unit 27 in the ultrasound image from position information of the marker identifying unit 27 included in the ultrasound image obtained by the transducer 41 in the accommodation lumen 21. Therefore, the ultrasound catheter 10 allows the surgeon to easily identify a predetermined direction of the patient's body, for example, the ventral direction, in the two-dimensional ultrasound image obtained by the transducer 41 moving within the outer sheath 20 along the axis of the outer sheath 20 and / or in the three-dimensional image of the biological tissue generated based on the two-dimensional ultrasound image.

[0079] The ultrasound catheter 10 further includes a distal cap 22 connected to the distal end of the outer sheath 20, the marker comparison unit being provided in the distal cap 22, and the marker identification unit 27 extending proximally beyond the proximal end of the distal cap 22 of the outer sheath 20. This makes it possible to identify the direction of the ultrasound image within the body using the distal marker 26 and the distal cap 22. Furthermore, because the distal cap 22, which is the marker comparison unit, is unlikely to enter the observable range of the transducer 41, it is possible to prevent the ultrasound image obtained by the transducer 41 from having a range that cannot be observed by the marker comparison unit.

[0080] The width of the marker identification portion 27 in the circumferential direction of the outer sheath 20 is 0.5 to 1.5 mm. This allows the marker identification portion 27 to be stably identified by X-ray photography and also stably identified by ultrasound images obtained by the transducer 41.

[0081] The outer sheath 20 also has at least one bent portion 24 at a different position in the axial direction, and a radiopaque second marker 28 is disposed at the bent portion 24 or at a position adjacent to the bent portion 24 of the outer sheath 20. This allows the ultrasound catheter 10 to freely adjust the distance and angle of the transducer 41 in the accommodation lumen 21 relative to the observation target while grasping the position of the bent portion 24 by rotating the outer sheath 20 while observing the second marker 28 by X-ray photography. Therefore, the ultrasound catheter 10 can acquire highly accurate images of the observation target even when inserted into a wide lumen.

[0082] The width of the second marker 28 in the circumferential direction of the outer sheath 20 is 0.2 to 0.5 mm. As a result, the second marker 28 has little effect on the ultrasound image, and therefore, it is possible to prevent the occurrence of a range that cannot be observed due to the second marker 28 in the ultrasound image obtained by the transducer 41.

[0083] The ultrasound catheter system 1 according to this embodiment includes the ultrasound catheter 10, a drive unit 80 for driving the ultrasound catheter 10, and a control device 100 for controlling the drive unit 80. The drive unit 80 includes a moving unit 82 for moving the drive shaft 50 along the axis of the outer sheath under the control of the control device 100. The control device 100 includes a control unit 101 for controlling the moving unit 82, a display unit 103 for receiving signals from the control unit 101 and displaying images, and an input unit 102 for receiving information from the outside and transmitting the information to the control unit 101. The control unit 101 receives signals from the transducer 41 via the drive unit 80 to generate two-dimensional ultrasound images and / or three-dimensional images and displays them on the display unit 103. The control unit 101 identifies the direction of the marker identification unit 27 in the two-dimensional ultrasound images and / or three-dimensional images automatically or by input from the input unit 102, and controls the display unit 103 to display a mark M indicating the direction of the marker identification unit 27 together with the two-dimensional ultrasound images and / or three-dimensional images. Input from the input unit 102 includes the operator moving the mark M on the screen of the display unit 103 using, for example, a keyboard or a mouse, and placing the mark M in the direction in which the marker identifying unit 27 exists.

[0084] The ultrasound catheter system 1 configured as described above can identify the orientation of the marker identifier 27 disposed in the outer sheath 20 from relative position information of the marker identifier 27 with respect to the tip cap 22 (marker comparison unit) obtained by X-ray imaging performed from outside the body, and can also acquire the position information of the marker identifier 27 when acquiring an ultrasound image obtained by the transducer 41 in the accommodating lumen 21. Therefore, the ultrasound catheter system 1 enables the surgeon to easily identify a predetermined direction of the patient's body, for example, the ventral direction, in a two-dimensional ultrasound image acquired by the transducer 41 moving within the outer sheath 20 along the axis of the outer sheath 20 and / or a three-dimensional image of biological tissue generated based on the two-dimensional ultrasound image.

[0085] The control unit 101 also generates a three-dimensional image of the biological tissue based on the two-dimensional ultrasound image and displays it on the display unit 103. The control unit 101 also displays a mark M indicating the direction of the marker identification unit 27 identified from the two-dimensional ultrasound image together with the three-dimensional image U1 of the biological tissue on the display unit 103. This allows the ultrasound catheter system 1 to enable the surgeon to easily identify the direction of the three-dimensional image U1 of the biological tissue generated based on the two-dimensional ultrasound image acquired by the transducer 41 moving along the axis inside the outer sheath 20.

[0086] Furthermore, the control unit 101 generates a three-dimensional model image U2 that shows a simplified shape of the human body on three-dimensional coordinates different from the three-dimensional image U1 of the biological tissue, and synchronizes the orientations of the three-dimensional image U1 of the biological tissue and the three-dimensional model image U2 to display them on the display unit 103. This allows the surgeon to observe the three-dimensional image U1 of the biological tissue while comparing it with the three-dimensional model image U2, and therefore makes it possible to easily identify the orientation of the three-dimensional image U1 of the biological tissue within the body.

[0087] Furthermore, when the control unit 101 receives information from the input unit 102 to change the orientation of the 3-dimensional image U1 of the biological tissue or the 3-dimensional model image U2 on the display unit 103, the control unit 101 changes the orientation of the 3-dimensional image U1 of the biological tissue and the 3-dimensional model image U2 in synchronization and displays them on the display unit 103. This allows the surgeon to synchronize and adjust the orientation of the 3-dimensional image U1 of the biological tissue and the 3-dimensional model image U2 to an orientation that is easy to view, making it possible to easily identify the orientation of the 3-dimensional image U1 of the biological tissue within the body.

[0088] The present invention is not limited to the above-described embodiment, and various modifications may be made by those skilled in the art within the technical spirit of the present invention. For example, as in a first modification shown in FIG. 11(A), the marker comparison unit 29 may be provided on the distal marker 26 rather than on the distal cap 22. The marker comparison unit 29 extends a predetermined length from the marker identification unit 27 to one circumferential side at the base end of the distal marker 26. The marker identification unit 27 and the marker comparison unit 29 may be formed integrally or separately. Because the circumferential length of the marker comparison unit 29 is longer than the circumferential length of the marker identification unit 27, the surgeon can identify the direction in which the marker identification unit 27 faces by comparing the position and shape of the marker identification unit 27 with the position and shape of the marker comparison unit 29 using an X-ray image. Because the marker comparison unit 29 does not extend in both circumferential directions from the marker identification unit 27, the surgeon can identify the depth positional relationship of the marker identification unit 27 with the marker comparison unit 29 using only the image obtained by X-ray imaging. The axial position of the marker comparison unit 29 relative to the marker identification unit 27 is not particularly limited. For example, as in a second modified example shown in Fig. 11(B), the marker comparison unit 29 may extend from approximately the center in the axial direction of the marker identification unit 27 to one side in the circumferential direction. Furthermore, as in a third modified example shown in Fig. 11(C), the marker comparison unit 29 may extend from the tip end of the marker identification unit 27 to one side in the circumferential direction.

[0089] 12(A), the marker comparison unit 29 may extend to one side in the circumferential direction from each of the distal end and proximal end of the marker identification unit 27. Furthermore, as in a fifth modification shown in FIG. 12(B), the direction in which the marker comparison unit 29 extends in the circumferential direction from each of the distal end and proximal end of the marker identification unit 27 may be the opposite direction to that of the fourth modification.

[0090] 13(A), the marker comparison portion 29 may be disposed not on the distal cap 22 but on one side of the distal marker 26, spaced apart from the distal marker 26 at a predetermined angle in the circumferential direction. The length of the marker comparison portion 29 in the axial direction of the outer sheath 20 is shorter than the length of the marker identification portion 27 in the axial direction. Because the shape of the marker comparison portion 29 is different from the shape of the marker identification portion 27, the surgeon can identify the marker identification portion 27 without confusing it with the marker comparison portion 29. The marker comparison portion 29 is disposed on one side of the proximal end of the distal marker 26, spaced apart from the proximal end of the distal marker 26 at a predetermined angle (e.g., 90°). The circumferential length of the marker comparison portion 29 is not particularly limited and may be longer, shorter, or substantially the same as the circumferential length of the marker identification portion 27. The surgeon can identify the direction in which the marker identification portion 27 faces by comparing the position and shape of the marker identification portion 27 with the position and shape of the marker comparison portion 29 using an X-ray image. Because the marker comparison unit 29 is not disposed on either side of the marker identification unit 27 in the circumferential direction, the surgeon can determine the positional relationship of the marker identification unit 27 with respect to the marker comparison unit 29 in the depth direction solely from the image obtained by X-ray imaging. The axial position of the marker comparison unit 29 with respect to the marker identification unit 27 is not particularly limited. For example, as in a seventh modified example shown in FIG. 13(B), the marker comparison unit 29 may be disposed away from approximately the center of the axial direction of the marker identification unit 27 to one side in the circumferential direction. Furthermore, as in an eighth modified example shown in FIG. 13(C), the marker comparison unit 29 may be disposed away from the tip of the marker identification unit 27 to one side in the circumferential direction.

[0091] 14(A), the marker comparison unit 29 may extend a predetermined length from the tip of the tip marker 26 to one side in the circumferential direction at a position overlapping the tip cap 22. Preferably, the tip cap 22 is not radiopaque so that the marker comparison unit 29 overlapping the tip cap 22 can be identified by an X-ray image. Also, as in a tenth modification shown in FIG. 14(B), the direction in which the marker comparison unit 29 extends in the circumferential direction from the tip of the marker identification unit 27 may be the opposite direction to that of the ninth modification.

[0092] 15(A), the marker comparison unit 29 may be disposed at a position overlapping the tip cap 22, spaced apart at a predetermined angle (e.g., 90°) to one side in the circumferential direction from the tip of the tip marker 26. Note that it is preferable that the tip cap 22 is not radiopaque so that the marker comparison unit 29 overlapping the tip cap 22 can be identified by an X-ray image. Furthermore, as in a twelfth modification shown in FIG. 15(B), the marker comparison unit 29 may be disposed at a predetermined angle (e.g., 90°) to both sides in the circumferential direction from the tip of the marker identification unit 27.

[0093] The ultrasound catheter may also be configured so that the transducer does not rotate.

[0094] The three-dimensional model image U2 may also be displayed on the same screen as the two-dimensional ultrasound image with the marker M. This allows the surgeon to easily understand in which direction of the patient's body the marker M on the two-dimensional ultrasound image is placed.

[0095] 16 , a covering tube 110 made of the same material as the outer sheath 20 may be placed on the outer surface of the marker identifying portion 27, which is disposed on the outer surface of the outer sheath 20, to cover the outer surface of the marker identifying portion 27. The covering tube 110 is thermally fixed to the portion of the outer sheath 20 that it contacts, thereby preventing the marker identifying portion 27 from being exposed to the outside. This prevents the marker identifying portion 27 from rubbing against the inner wall of the blood vessel, damaging the inner wall, or becoming detached. The covering tube is preferably made of the same material as the portion of the outer sheath 20 that it contacts. This allows the interface between the covering tube and the portion of the outer sheath 20 that it contacts to fuse together by heat, more reliably preventing the covering tube from rolling up or becoming detached from the outer sheath 20.

[0096] Furthermore, the marker identifier 27 and the ultrasound radiation surface of the transducer 41 may be parallel to each other. Specifically, both the surface of the marker identifier 27 facing the transducer 41 (the radially inner surface) and the ultrasound radiation surface of the transducer 41 are arranged substantially parallel to the axis of the outer sheath 20. This makes it easier to identify the direction in which the marker identifier 27 is located in the two-dimensional ultrasound image obtained from the transducer unit 40.

[0097] Furthermore, by roughening the surface of the marker identifier 27 facing the axis of the outer sheath 20, i.e., the surface facing radially inward, to form fine irregularities, ultrasonic waves can be more effectively reflected, and a strong white color can be more clearly formed in the two-dimensional ultrasound image. Therefore, in the two-dimensional ultrasound image obtained from the transducer unit 40, the white color formed by the roughening makes it easier to identify the direction of the marker identifier 27.

[0098] This application is based on Japanese Patent Application No. 2020-142770 filed on August 26, 2020, the disclosures of which are incorporated herein by reference in their entirety. [Explanation of symbols]

[0099] 1. Ultrasound catheter system 10 Ultrasound catheter 20 outer sheath 21 lumens 22 Tip cap (marker comparison part) 24 Bend 26 Tip Marker 27 Marker Identification Section 28 Second Marker 29 Marker Comparison Section 30 Inner sheath 40 transducer unit 41 Oscillator 50 drive shaft 80 Drive Unit 81 Drive unit 82 Mobile Unit 100 control device 101 Control section 102 Input section 103 Display section 110 Coated tube M landmark U1 3D image of biological tissue U2 3D model image

Claims

1. An outer sheath having a receiving lumen formed therein that communicates from the base end to the tip end; a drive shaft movable within the outer sheath along an axis of the outer sheath; a transducer disposed within the accommodation lumen and fixed to a tip of the drive shaft, the transducer being capable of transmitting and receiving ultrasonic waves; a radiopaque tip marker disposed at the tip of the outer sheath, an ultrasound catheter, wherein the tip marker has a marker identifying portion extending along the axis in a portion of the circumferential direction, and a marker comparing portion formed in a circumferential direction or radial direction of the outer sheath at a different length and / or a different arrangement from the marker identifying portion; a drive unit that drives the ultrasound catheter; a control device for controlling the drive unit, The drive unit is an ultrasound catheter system having a moving unit controlled by the control device to move the drive shaft along the axis of the outer sheath, The control device a control unit capable of controlling the moving unit; a display unit capable of receiving a signal from the control unit and displaying an image; an input unit that can receive information from an external device and transmit the information to the control unit; the control unit receives a signal from the transducer via the drive unit to generate a two-dimensional ultrasound image and / or a three-dimensional image, and displays the image on the display unit; the control unit specifies the direction of the marker identification part in the two-dimensional ultrasound image and / or the three-dimensional image automatically or by input from the input unit; and controls the display unit to display a mark indicating the direction of the marker identification part together with the two-dimensional ultrasound image and / or the three-dimensional image; The control unit receives a signal from the transducer via the drive unit to generate a three-dimensional image of the biological tissue, which is displayed on the display unit, and controls the display unit to display a mark indicating the direction of the marker identification portion identified from the two-dimensional ultrasound image together with the three-dimensional image of the biological tissue.

2. 2. The ultrasound catheter system according to claim 1, wherein the control unit generates a three-dimensional model image showing a simplified shape of the human body on three-dimensional coordinates different from that of the three-dimensional image of the biological tissue, and displays the three-dimensional image of the biological tissue and the three-dimensional model image on the display unit in synchronized orientations.

3. 3. The ultrasound catheter system according to claim 2, wherein when the control unit receives information from the input unit to change the orientation of the 3D image of the biological tissue or the 3D model image on the display unit, the control unit synchronously changes the orientation of the 3D image of the biological tissue and the 3D model image and displays them on the display unit.

4. The ultrasonic catheter further comprises a tip cap connected to the tip of the outer sheath, the marker comparison section is provided on the tip cap, 4. The ultrasound catheter system according to claim 1, wherein the marker identifying portion extends further to the proximal end side than the proximal end of the distal end cap of the outer sheath.

5. An ultrasound catheter system as described in any one of claims 1 to 4, characterized in that the width of the marker identification portion in the circumferential direction of the outer sheath is 0.5 to 1.5 mm.

6. The outer sheath has one bending portion or at least two bending portions at different positions in the axial direction, 6. The ultrasound catheter system according to claim 1, wherein a second marker that is radiopaque is disposed at the bent portion of the outer sheath or at a position adjacent to the bent portion.

7. An ultrasound catheter system as described in Claim 6, characterized in that the width of the second marker in the circumferential direction of the outer sheath is 0.2 to 0.5 mm.

8. A coating tube covering the tip marker arranged on the outer peripheral surface of the outer sheath, 8. The ultrasound catheter system according to claim 1, wherein at least a portion of the covering tube is fixed to the outer sheath.

9. An ultrasound catheter system described in any one of claims 1 to 8, characterized in that the surface of the marker identification unit facing the transducer and the ultrasound irradiation surface of the transducer are parallel to the axis of the outer sheath.

10. An ultrasound catheter system as described in any one of claims 1 to 9, characterized in that the surface of the marker identification part facing the axis of the outer sheath is roughened.

Images