Image acquisition catheters and catheter devices

Abstract

The present invention provides an imaging catheter and catheter device that enable smooth movement of the image acquisition unit in the radial and circumferential directions on the cross-section of a biological lumen by performing operations such as expanding the balloon or rotating it at the user's fingertips, thereby enabling more accurate imaging of lesions formed within a biological lumen. [Solution] The image acquisition catheter 10 has a first elongated body 100 in which an image acquisition unit 120 for acquiring tomographic images of blood vessel B is located at the distal end, and a second elongated body 200 which has expandable and contractible balloons 230 and 240 located at the distal end, and a proximal operating unit 250 located at the proximal end that enables proximal operation. The balloons are connected to the outer surface near the distal end of the first elongated body, and the first elongated body is configured to rotate in conjunction with the operation when the proximal operating unit located at the proximal end of the second elongated body is rotated along the circumferential direction of the biological lumen.

Description

【Technical Field】 【0001】 The present invention relates to a catheter for image acquisition and a catheter device. 【Background Art】 【0002】 As a medical device used to acquire diagnostic images for diagnosing lesions and the like in a living body, development of an IVUS catheter using intravascular ultrasound (IVUS), an OCT catheter using optical coherence tomography (OCT), an OFDI catheter using optical frequency domain imaging (OFDI), etc. has been advanced. 【0003】 In a medical field, in a procedure using an image acquisition catheter as described above, the procedure progress method and treatment policy may be determined based on the acquired image of a living body lumen (for example, a tomographic image of a blood vessel). 【0004】 In a treatment using an image acquisition catheter, an operator or the like moves the image acquisition catheter along a guide wire introduced into a blood vessel, and delivers an image acquisition unit (sensor unit) arranged near the distal portion of the image acquisition catheter to a lesion to be observed. 【0005】 For example, when acquiring an image of a large-diameter lower limb artery compared to a blood vessel of the heart or the like, if the guide wire is arranged at a position close to the blood vessel wall, and accordingly the image acquisition unit of the image acquisition catheter through which the guide wire is inserted is arranged at a position close to the blood vessel wall, there is a concern about the occurrence of "frame out" in which the blood vessel wall on the opposite side of the position where the image acquisition unit is arranged and its peripheral portion are not reflected in the tomographic image. 【0006】 Furthermore, in catheters with a structure that irradiates light from the image acquisition unit toward the blood vessel wall, such as OCT catheters and OFDI catheters, if imaging is performed with the guidewire positioned close to the blood vessel wall, the light irradiated from the image acquisition unit may be blocked by the guidewire, and the shadow of the guidewire may be projected onto the blood vessel wall on the opposite side of where the guidewire is positioned. This can result in a defect in the tomographic image due to the shadow of the guidewire (a black area where the shadow is projected). The larger the diameter of the blood vessel being imaged, the larger the shadow of the guidewire will be on the opposite side of the vessel, and the more pronounced this problem may become. 【0007】 Operators may attempt to adjust the position and orientation of the imaging catheter, for example, by manipulating it manually, to prevent the catheter from going out of frame or casting shadows. However, when a guidewire is attached to the imaging catheter, the operability of the imaging catheter depends on the physical properties and insertion state of the guidewire, making it difficult to freely adjust the position of the imaging catheter on the cross-section of the blood vessel. 【0008】 In relation to these challenges, Patent Document 1 proposes an image acquisition catheter equipped with a moving member (elastic member) that applies a radial elastic force to the sheath and moves the sheath in the radial direction. [Prior art documents] [Patent Documents] 【0009】 [Patent Document 1] Japanese Patent Publication No. 2015-109885 [Overview of the Initiative] [Problems that the invention aims to solve] 【0010】 When using the image acquisition catheter described in Patent Document 1, the sheath, which is positioned close to the blood vessel wall, can be moved radially by a moving member. Therefore, even if the image acquisition unit is positioned close to one side of the blood vessel wall, the image acquisition unit can be positioned close to the opposite side of the blood vessel wall by moving the sheath to the opposite side of the blood vessel wall using the moving member. This makes it possible to acquire an image of the opposite side of the blood vessel wall. 【0011】 However, when the above-mentioned moving member is used, the sheath is forcibly moved to a position where it contacts the opposite side of the blood vessel wall. If the sheath is positioned extremely close to the opposite side of the blood vessel wall, it becomes difficult to image the blood vessel wall on the opposite side, making it difficult to solve problems such as frame-out and shadows of the guidewire. In addition, in the image acquisition catheter of Patent Document 1, the elastic force of the moving member is used to press the sheath against the blood vessel wall, so when operations such as moving the image acquisition catheter circumferentially along the blood vessel wall are performed, the sheath is rubbed against the blood vessel wall with great force, which increases the burden on the blood vessel wall. 【0012】 The present invention has been made in response to the above problems, and aims to provide an image acquisition catheter and catheter device that enable smooth movement of the image acquisition unit in the radial and circumferential directions on the cross-section of a biological lumen by performing operations to expand the balloon or rotate it at the hand, thereby enabling more accurate imaging of lesions within a biological lumen. [Means for solving the problem] 【0013】 The present invention can be achieved by any one of the following means (1) to (10). 【0014】 (1) A first elongated body having an image acquisition unit for obtaining tomographic images of the biological lumen located at its distal end, It has a second elongated body comprising an expandable and deflated balloon located at the distal end, and a hand-operated control unit located at the proximal end for hand-operated operation, The balloon is connected to the outer surface near the distal portion of the first elongated body, The first elongated body is configured to rotate in conjunction with the operation of rotating the proximal operating section, which is located at the proximal end of the second elongated body, along the circumferential direction of the biological lumen, in an image acquisition catheter. 【0015】 (2) The second elongated body comprises two or more balloons spaced apart in the axial direction of the second elongated body, Each of the balloons is connected to the outer surface of the second elongated body, an image acquisition catheter as described in (1). 【0016】 (3) The first elongated body comprises an image acquisition unit having an ultrasonic receiving unit or an optical transmitting / receiving unit, and a sheath having a lumen from which the image acquisition unit can move, as described in (1) or (2). 【0017】 (4) The image acquisition catheter according to (3), wherein the balloon is connected to the outer surface of the sheath at a distal or proximal position within the range in which the image acquisition unit can move within the sheath. 【0018】 (5) The first elongated body and the second elongated body are separated from each other except at the connection point of the balloon, an image acquisition catheter according to any one of (1) to (4). 【0019】 (6) A long body with an image acquisition unit located at its distal end for obtaining tomographic images of the lumen of a living organism, The long body has a housing section provided on the outer surface of the distal end, which has a housing lumen capable of accommodating an expandable and deflated balloon, The aforementioned housing section is configured to expand in conjunction with the expansion of the balloon positioned within the housing lumen, and is an image acquisition catheter. 【0020】 (7) The elongate body of the catheter for image acquisition according to (6) includes two or more of the accommodating portions spaced apart in the axial direction of the elongate body. 【0021】 (8) The elongate body of the catheter for image acquisition according to (6) or (7) is constituted by a sheath having a lumen in which the image acquisition portion including an ultrasonic receiving portion or an optical transmitting and receiving portion is movable. 【0022】 (9) The accommodating portion of the catheter for image acquisition according to (8) is disposed at a distal position or a proximal position within a range where the image acquisition portion is movable in the sheath. 【0023】 (10) The catheter for image acquisition according to any one of (6) to (9), and a balloon catheter including a balloon configured to be insertable into the accommodating lumen at a distal portion and disposed at a proximal portion, and a hand operation portion enabling operation at the operator's hand. The elongate body of the catheter device is configured to be rotatable in accompaniment with an operation of rotating the hand operation portion along the circumferential direction of the living body lumen when the balloon disposed in the accommodating lumen is in an expanded state. 【Advantages of the Invention】 【0024】 According to the catheter for image acquisition and the catheter device according to the present invention, by performing an operation of expanding the balloon or an operation of rotating by hand, the image acquisition portion can be smoothly moved in the radial direction and the circumferential direction on the cross section of the living body lumen. Thereby, more accurate imaging of a lesion portion in the living body lumen can be performed. 【Brief Description of the Drawings】 【0025】 [Figure 1] It is a diagram schematically showing an image diagnosis apparatus according to an embodiment. [Figure 2]This is an enlarged cross-sectional view of the area near the first balloon of the image acquisition catheter according to the embodiment. [Figure 3] This is an enlarged cross-sectional view of the area near the second balloon of the image acquisition catheter according to the embodiment. [Figure 4] This is a schematic cross-sectional view illustrating an example of use and effects of an image acquisition catheter according to the embodiment. [Figure 5] This is a schematic cross-sectional view illustrating an example of use and effects of an image acquisition catheter according to the embodiment. [Figure 6] This is a schematic cross-sectional view illustrating an example of use and effects of an image acquisition catheter according to the embodiment. [Figure 7] This diagram shows a simplified image acquisition catheter related to a modified example. [Figure 8] This is an enlarged cross-sectional view of the area near the first housing portion of the image acquisition catheter according to the modified example. [Figure 9] This is an enlarged cross-sectional view of the area near the second housing portion of the image acquisition catheter in the modified form. [Modes for carrying out the invention] 【0026】 Embodiments of the present invention will be described below with reference to the attached drawings. Note that the following description does not limit the technical scope or the meaning of terms as defined in the claims. Furthermore, the dimensional ratios in the drawings are exaggerated for illustrative purposes and may differ from actual ratios. 【0027】 Figures 1 to 3 are diagrams illustrating the configuration of each part of the image acquisition catheter 10 according to the embodiment. Figures 3 to 6 are schematic cross-sectional views illustrating examples of use and effects of the image acquisition catheter 10. 【0028】 In this specification, in the image acquisition catheter 10, the side inserted into the body (indicated by arrow X1 in the figure) is referred to as the "distal side," and the side opposite the distal side, where each hub 140 and the proximal control unit 250 are located (indicated by arrow X2 in the figure), is referred to as the "proximal side." Furthermore, the end located on the distal side and its surrounding area are referred to as the "distal portion," and the end located on the proximal side and its surrounding area are referred to as the "proximal portion." 【0029】 The direction in which the first and second elongated bodies 100 and 200 extend (indicated by arrows X1-X2 in the figure) is defined as the "axial direction." Furthermore, the cross-section perpendicular to the axial direction of the image acquisition catheter 10 is defined as the "orthoaxial cross-section." The cross-sectional views shown in Figures 4 to 6 are schematic transverse cross-sections of blood vessel B corresponding to the orthoaxial cross-section of the image acquisition catheter 10. 【0030】 (Image diagnostic device 1) Figure 1 shows the medical imaging apparatus 1 according to this embodiment. 【0031】 The diagnostic imaging device 1 comprises an image acquisition catheter 10, an external drive unit (Motor Drive Unit) M, a controller C, and an image display unit D. 【0032】 The diagnostic imaging device 1 is configured as a medical system capable of displaying tomographic images of biological tubular lumen acquired by the first elongated body 100. 【0033】 In this embodiment, a blood vessel B is exemplified as a biological lumen to which the image acquisition catheter 10 is used. Examples of blood vessel B include the lower extremity arteries that run through the patient's lower limbs. Lower extremity arteries are generally larger in diameter than the blood vessels of the heart (e.g., coronary arteries). As will be described later, by using the image acquisition catheter 10, it becomes possible to acquire more accurate tomographic images of blood vessel B and lesions even when imaging relatively large blood vessels such as lower extremity arteries. 【0034】 Furthermore, the biological lumen to which the imaging catheter 10 can be used is not limited to blood vessel B, but may also be, for example, the bile duct, trachea, esophagus, urethra, ear, nose, and throat lumen, etc. Also, even when the imaging catheter 10 is used on blood vessel B, it is possible to select blood vessels other than the lower limb arteries as the target vessels. 【0035】 The external drive device M is a device that generates a driving force to move the imaging shaft 130 of the first elongated body 100 along the axial direction of the sheath 110 when acquiring a tomographic image of blood vessel B. 【0036】 Controller C comprehensively controls the operation of each part of the diagnostic imaging device 1. The controller C controls the operation of the external drive unit M, the image acquisition unit 120 of the image acquisition catheter 10, and the image display unit D. Controller C may include, for example, a known microcomputer equipped with a CPU, RAM, ROM, etc. There are no particular restrictions on the communication method between Controller C and other devices; for example, it may be wired communication or wireless communication. 【0037】 The image display unit D can be a known monitor equipped with a display capable of outputting audio and music, and displaying still images and videos. The image display unit D displays tomographic images acquired by the image acquisition catheter 10 based on operation commands transmitted from the controller C. The image display unit D may be, for example, a display equipped in a portable or non-portable information terminal device. 【0038】 (Catheter 10 for image acquisition) As shown in Figures 1 to 3, the image acquisition catheter 10 comprises a first elongated body 100 having an image acquisition unit 120 for acquiring tomographic images of blood vessel B located at its distal end, and a second elongated body 200 having a plurality of expandable and deflated balloons 230, 240 located at its distal end, and a proximal operating unit 250 that enables operation at the proximal end. 【0039】 As shown in Figure 1, the second elongated body 200 includes a first balloon 230 positioned distal to the shaft 210 of the second elongated body 200, and a second balloon 240 positioned proximal to the first balloon 230. 【0040】 As shown in Figures 2 and 3, each balloon 230, 240 is connected to the outer surface near the distal end of the first elongated body 100. More specifically, each balloon 230, 240 is connected to the outer surface of the sheath 110 provided by the first elongated body 100. 【0041】 The first elongated body 100 is configured to rotate in conjunction with the operation of rotating the handheld operating section 250, which is located at the proximal end of the second elongated body 200, along the circumferential direction of the blood vessel B. 【0042】 In this embodiment, the first elongated body 100 is configured to acquire a tomographic image of blood vessel B. On the other hand, the second elongated body 200 is configured to allow the image acquisition unit 120 of the first elongated body 100 to be moved radially (radial movement on the cross-section perpendicular to the axis shown in Figures 4 to 6) and circumferentially (circumferential movement along the blood vessel wall Bi of blood vessel B shown in Figures 4 to 6). 【0043】 (First long body 100) The first elongated body 100 comprises a sheath 110 with an axially extending lumen 115. An imaging shaft 130, equipped with an image acquisition unit 120 at its distal end, is positioned within the lumen 115. 【0044】 The first elongated body 100 can be composed of, for example, an IVUS catheter that uses ultrasound to acquire tomographic images, or an OCT catheter (or OFDI catheter) that uses light of a predetermined wavelength. 【0045】 When the first elongated body 100 is composed of an IVUS catheter, the image acquisition unit 120 can be composed of an imaging core equipped with an ultrasound transmitting and receiving unit. Furthermore, when the first elongated body 100 is composed of an OCT catheter or OFDI, the image acquisition unit 120 can be composed of an imaging core equipped with an optical transmitting and receiving unit. Regarding the specific structure of the image acquisition unit 120 (imaging core) equipped with an ultrasound transmitting and receiving unit or an optical transmitting and receiving unit, any known structure for an image acquisition catheter can be arbitrarily adopted. 【0046】 The imaging shaft 130 can move within the lumen 115 of the sheath 110 by the operation of the external drive device M. The image acquisition unit 120, located at the distal end of the imaging shaft 130, moves within the lumen 115 of the sheath 110 in the axial direction as the imaging shaft 130 moves in the axial direction. 【0047】 A proximal hub 140 is positioned at the proximal end of the sheath 110, which allows the sheath 110 to be mechanically connected to an external drive unit M. 【0048】 The imaging shaft 130 has a long tube and signal lines (electrical signal lines, optical fibers, etc.) inserted inside the tube that enable various types of communication with the external drive device M. The tube can be made of, for example, multiple layers of coils with different winding directions around the axis. As materials for the coils, for example, stainless steel or Ni-Ti (nickel-titanium) alloy can be used. 【0049】 The lumen 115 of the sheath 110 extends to the vicinity of the proximal part of the sheath 110. The lumen 115 of the sheath 110 communicates with the internal space of the proximal hub 140. The imaging shaft 130, inserted into the lumen 115 of the sheath 110, is electrically connected to the external drive unit M by a connection part provided in the proximal part of the proximal hub 140, which is connected to the external drive unit M. 【0050】 As shown in Figure 1, with the proximal hub 140 connected to the external drive unit M, when the proximal hub 140 is pushed distally, the imaging shaft 130 and image acquisition unit 120 move forward (forward) with the lumen 115 of the sheath 110 distally. Conversely, when the external drive unit M is activated and the proximal hub 140 is pulled proximal, the imaging shaft 130 and image acquisition unit 120 move backward (pullback) with the lumen 115 of the sheath proximal. Driven by the driving force supplied from the external drive unit M, the imaging shaft 130 and image acquisition unit 120 move forward and backward along the axial direction of the sheath 110 as described above, while rotating (radial scanning) and imaging the blood vessel B in a 360-degree direction. 【0051】 The range in which the imaging shaft 130 and the image acquisition unit 120 advance and retract within the lumen 115 of the sheath 110 is the range between the advance limit position P1 and the retraction limit position P2 shown in Figures 1 to 3. 【0052】 The forward limit position P1 can be set, for example, at a position 5 mm to 30 mm proximal to the distal end (tip) of the sheath 110. The backward limit position P2 can be set at a position 100 mm to 150 mm proximal to the forward limit position P1. When the positions of the forward limit position P1 and the backward limit position P2 are set as described above, the distance that the imaging shaft 130 and the image acquisition unit 120 can advance and retract in the axial direction can be set, for example, to 100 mm to 150 mm. 【0053】 As shown in Figures 1 to 3, the sheath 110 is provided with an observation window 119. The observation window 119 is configured to allow ultrasound (or light) emitted from the image acquisition unit 120 located in the lumen 115 of the sheath 110 to pass through. "Penetrateable" means that the refractive index of the ultrasound (or light) is low (high transmittance) to such an extent that the image quality of the tomographic image acquired using the image acquisition catheter 10 is not significantly impaired. 【0054】 The observation window 119 can be formed to be approximately the same length as the distance between the forward limit position P1 and the backward limit position P2. As will be described later, the first connection part 117a, which connects the first balloon 230 to the sheath 110, is located distal to the forward limit position P1, and the second connection part 117b, which connects the second balloon 240 to the sheath 110, is located proximal to the backward limit position P2. Therefore, the observation window 119 is formed between a position proximal to the first connection part 117a and a position distal to the second connection part 117b. 【0055】 The lumen 115 of the sheath 110 is in communication with the port 141 via the internal space of the proximal hub 140. 【0056】 When the first elongated body 100 is configured as an IVUS catheter, priming fluid is supplied to the lumen 115 of the sheath 110 before use. When the sheath 110 is inserted into blood vessel B with the lumen 115 of the sheath 110 filled with priming fluid, the priming fluid is interposed between the image acquisition unit 120 and the blood vessel wall Bi of blood vessel B. By emitting ultrasound from the image acquisition unit 120 in this state, the ultrasound is transmitted well to the blood vessel wall Bi of blood vessel B via the priming fluid. In addition, the image acquisition unit 120 becomes able to efficiently receive ultrasound reflected from the blood vessel wall Bi of blood vessel B. 【0057】 The priming solution can be injected via port 141. An injection device (e.g., a syringe) for injecting the priming solution can be connected to port 141. For example, physiological saline can be used as the priming solution. 【0058】 As shown in Figure 2, a reinforcing member 114 is positioned in the distal part of the lumen 115 of the sheath 110. The reinforcing member 114 has a hole 114a that communicates with the lumen 115 of the sheath 110, which is located proximal to the reinforcing member 114. In addition, a priming hole 115a is formed in the distal part of the sheath 110, which communicates with the hole 114a. 【0059】 The holes 114a and priming holes 115a are provided to discharge the priming fluid that has filled the lumen 115 of the sheath 110. When the lumen 115 of the sheath 110 is sufficiently filled with priming fluid, the sheath 110 discharges the excess priming fluid to the outside of the lumen 115 through the holes 114a and priming holes 115a. 【0060】 As shown in Figures 1 and 2, the first elongated body 100 has a first connecting portion 117a to which the first balloon 230 is connected, and a second connecting portion 117b to which the second balloon 240 is connected. 【0061】 The first connecting portion 117a is provided on the outer surface near the distal end of the sheath 110 and connects the sheath 110 to the first balloon 230. 【0062】 The second connecting portion 117b is located on the outer surface of the sheath 110, proximal to the position where the first connecting portion 117a is provided, and connects the sheath 110 to the second balloon 240. 【0063】 Each connecting portion 117a, 117b can be made of, for example, an adhesive that connects the sheath 110 to each balloon 230, 240, or a fused portion where the sheath 110 and each balloon 230, 240 are fused together. 【0064】 Each balloon 230, 240 is connected to the outer surface of the sheath 110 at a distal or proximal position within the range of movement of the image acquisition unit 120. 【0065】 In this embodiment, the first connecting portion 117a, which connects the first balloon 230 to the sheath 110, is located distal to the forward limit position P1. The second connecting portion 117b, which connects the second balloon 240 to the sheath 110, is located proximal to the retraction limit position P2. 【0066】 Because each balloon 230 and 240 is connected to the sheath 110 at the positions described above, when acquiring a tomographic image of blood vessel B using the image acquisition catheter 10, it is possible to prevent the ultrasound or light emitted from the image acquisition unit 120 from being blocked by each balloon 230 and 240. As a result, even when a structure is adopted in which each balloon 230 and 240 is connected to the outer surface of the first elongated body 100 (the outer surface of the sheath 110), as in this embodiment, it becomes possible for the image acquisition unit 120 to acquire a clear tomographic image. 【0067】 As shown in Figure 1, the first elongated body 100 and the second elongated body 200 are separated from each other except for the connection points (connection parts 117a and 117b) of the balloons 230 and 240. Therefore, with the proximal hub 140 of the first elongated body 100 mechanically connected to the external drive device M, the operator can independently operate the handheld control unit 250 located on the proximal side of the second elongated body 200, thereby rotating the second elongated body 200 without interfering with the first elongated body 100. 【0068】 As materials for the sheath 110, various thermoplastic elastomers such as styrene-based, polyolefin-based, polyurethane-based, polyester-based, polyamide-based, polyimide-based, polybutadiene-based, trans-polyisoprene-based, fluororubber-based, and chlorinated polyethylene-based materials can be used. 【0069】 Other structures of the first elongated body 100 (for example, the structure of the connector part for connecting to the external drive device M, the structure of the port for priming, the tubular structure of the sheath 110, etc.) can be arbitrarily adopted from configurations known in the image acquisition catheter 10. 【0070】 (Second long version 200) As shown in Figures 1 to 3, the second elongated body 200 comprises two or more balloons 230, 240 spaced apart in the axial direction of the second elongated body 200. 【0071】 Figures 1 to 3 show the balloons 230 and 240 in their expanded state. Each balloon 230 and 240 can be kept in an unexpanded state, for example, before introducing the imaging catheter 10 into the body and before acquiring a tomographic image of blood vessel B using the imaging catheter 10. 【0072】 Each balloon 230 and 240 is connected to a different axial position on the sheath 110 of the first elongated body 100. Furthermore, each balloon 230 and 240 is positioned at approximately the same circumferential position relative to the axis O2 (see Figure 4) of the sheath 110 of the first elongated body 100. 【0073】 As shown in Figure 1, the second elongated body 200 includes a shaft 210 that extends in the axial direction. The balloons 230 and 240 are arranged on the shaft 210. 【0074】 As shown in Figures 2 and 3, the shaft 210 comprises an inner tube 210a having a guide wire lumen 211, and a plurality of outer tubes 210b, 210c having expansion lumens 212. 【0075】 The first outer tube 210b is positioned distal to the shaft 210 than the second outer tube 210c. The inner tube 210a is positioned to pass through each of the outer tubes 210b and 210c. The expanded lumen 212 is partitioned between the outer surface of the inner tube 210a and the inner surfaces of each of the outer tubes 210b and 210c. 【0076】 As shown in Figure 2, a certain range of the distal portion of the inner tube 210a is positioned to protrude distally to the first outer tube 210b. 【0077】 As shown in Figure 1, the opening formed in the proximal part of the inner tube 210a constitutes a guidewire port 215 that leads the guidewire GW to the outside of the guidewire lumen 211. The operator can insert the guidewire GW into the guidewire lumen 211 of the inner tube 210a by introducing the guidewire GW into the shaft 210 from the distal opening of the inner tube 210a. In this way, the first elongated body 100 is configured to have a so-called rapid exchange type catheter structure. 【0078】 A flexible tip 201 is attached to the distal end of the inner tube 210a. The tip 201 can be made of, for example, a known resin material. 【0079】 As shown in Figure 2, the distal end 231 of the first balloon 230 is connected to the inner tube 210a and the tip 201. The proximal end 233 of the first balloon 230 is connected near the distal end of the first outer tube 210b. 【0080】 The lumen 236 of the first balloon 230 is partitioned between the outer surface of the inner tube 210a and the inner surface of the first balloon 230. The lumen 236 of the first balloon 230 is also in communication with the expansion lumen 212 partitioned between the first outer tube 210b and the inner tube 210a. 【0081】 As shown in Figure 2, the first balloon 230 can have a cross-sectional shape comprising a distal tapered portion 234a that narrows distally, a proximal tapered portion 234b that narrows proximally, and a straight portion 235 that extends substantially linearly between the distal tapered portion 234a and the proximal tapered portion 234b when expanded. However, there are no particular restrictions on the specific cross-sectional shape of the first balloon 230 before and after expansion. 【0082】 The inner tube 210a is equipped with a contrast marker 217a indicating the position of the proximal part of the distal tapered portion 234a of the first balloon 230 (the boundary position between the straight portion 235 and the distal tapered portion 234a), and a contrast marker 217b indicating the position of the distal part of the proximal tapered portion 234b of the first balloon 230 (the boundary position between the straight portion 235 and the proximal tapered portion 234b). Each contrast marker 217a, 217b can be made of, for example, a known metal material that is radiopaque. 【0083】 As shown in Figure 3, the second balloon 240 is connected to each of the outer tubes 210b and 210c. 【0084】 As shown in Figures 2 and 3, the first outer tube 210b extends between the balloons 230 and 240. Also, as shown in Figure 3, the second outer tube 210c extends proximal to the second balloon 240. 【0085】 As shown in Figure 3, the distal end of the second balloon 240 is connected near the proximal end of the first outer tube 210b. Also, the proximal end of the second balloon 240 is connected near the distal end of the second outer tube 210c. 【0086】 The lumen 246 of the second balloon 240 is partitioned between the outer surface of the inner tube 210a and the inner surface of the second balloon 240. The lumen 246 of the second balloon 240 is in communication with the expansion lumen 212 partitioned between the second outer tube 210c and the inner tube 210a. 【0087】 As shown in Figure 3, the second balloon 240 can have a cross-sectional shape comprising a distal tapered portion 244a that narrows distally, a proximal tapered portion 244b that narrows proximally, and a straight portion 245 that extends substantially linearly between the distal tapered portion 244a and the proximal tapered portion 244b when expanded. However, there are no particular restrictions on the specific shape of the second balloon 240 before and after expansion. 【0088】 The inner tube 210a is equipped with a contrast marker 217c indicating the position of the proximal part of the distal tapered portion 244a of the second balloon 240 (the boundary position between the straight portion 245 and the distal tapered portion 244a), and a contrast marker 217d indicating the position of the distal part of the proximal tapered portion 244b of the second balloon 240 (the boundary position between the straight portion 245 and the proximal tapered portion 244b). Each contrast marker 217c and 217d can be made of, for example, a known metal material that is radiopaque. 【0089】 A handheld control unit 250 located at the proximal end of the shaft 210 of the second elongated body 200 is provided with a port 251 to which an injection device (e.g., a syringe) can be connected for operating the injection and discharge of an expansion medium (e.g., a liquid such as physiological saline) to inflate each balloon 230, 240. 【0090】 When inflating balloons 230 and 240, the operator injects expansion medium from the proximal side of shaft 210 by operating an injection device connected to port 251. The expansion medium injected into shaft 210 passes through the expansion lumen 212 partitioned between the inner tube 210a and the second outer tube 210c, into the lumen 246 of the second balloon 240, and then passes through the expansion lumen 212 partitioned between the inner tube 210a and the first outer tube 210b, into the lumen 236 of the first balloon 230. Each balloon 230 and 240 expands when expansion medium flows into their respective lumens 236 and 246. When deflating balloons 230 and 240, the operator injects the expansion medium injected into each balloon 230 and 240 to the outside of shaft 210 via the expansion lumen 212 by operating the injection device connected to port 251. 【0091】 The proximal control unit 250 can be configured, for example, with a structure similar to that of a proximal hub provided in a known balloon catheter. 【0092】 For example, the materials used to make up each balloon 230 and 240 include polyethylene, polypropylene, ethylene-propylene copolymer polyolefin, polyester such as polyethylene terephthalate, polyvinyl chloride, ethylene-vinyl acetate copolymer, cross-linked ethylene-vinyl acetate copolymer, thermoplastic resins such as polyurethane, polyamide, polyamide elastomer, polystyrene elastomer, silicone rubber, latex rubber, and the like. 【0093】 Each balloon 230 and 240 can be provided with a coating layer (for example, a hydrophilic coating layer) on its outer surface that exhibits lubrication when in contact with bodily fluids (liquids) such as blood. By providing each balloon 230 and 240 with such a coating layer, even if the outer surface of each balloon 230 and 240 comes into contact with or rubs against the vessel wall Bi of vessel B when the image acquisition catheter 10 is rotated circumferentially within vessel B as described later, it becomes possible to reduce the burden on vessel B. 【0094】 For example, the same material as that used for the sheath 110 described above can be used to make up the shaft 210 (inner tube 210a and outer tubes 210b, 210c). 【0095】 In the image acquisition catheter 10 according to this embodiment, the shaft 210 of the second elongated body 200 can be configured to have higher rigidity and higher torque transmission than the sheath 110 of the first elongated body 100. When the operator places the image acquisition catheter 10 inside the blood vessel B and rotates the image acquisition unit 120 of the first elongated body 100 circumferentially along the blood vessel wall Bi of blood vessel B, the operator rotates the second elongated body 200 while grasping the hand-operated unit 250, which is located outside the patient's body, with their fingers or the like. Since the first elongated body 100 is mechanically connected to the external drive device M when acquiring a tomographic image of blood vessel B, it is not possible to rotate the first elongated body 100 circumferentially along the blood vessel wall Bi of blood vessel B by hand operation. In this case, if the rigidity and torque transmission capabilities of the shaft 210 of the second elongated body 200 are not sufficient, the rotation of the second elongated body 200 performed at the hand end cannot be transmitted to the distal end of the second elongated body 200, making it difficult to smoothly rotate the second elongated body 200 and the first elongated body 100 connected to the second elongated body 200 in the circumferential direction. 【0096】 For example, to prevent the above-mentioned problems from occurring, the constituent material of the shaft 210 of the second elongated body 200 can be selected so that the rigidity and torque transmission performance of the shaft 210 of the first elongated body 100 are higher than those of the sheath 110 of the first elongated body 100. In addition, for example, the shaft 210 can be provided with a base shaft that extends further proximal from the proximal part of the second outer tube 210c. The base shaft can be equipped with a relatively rigid reinforcing material such as metal. This can improve the rigidity and torque transmission performance of the shaft 210. 【0097】 Next, with reference to Figures 4 to 6, we will explain the usage examples and effects of the image acquisition catheter 10. Note that Figures 4 to 6 only show the first balloon 230 of the two balloons, but the operation and effects of the second balloon 240 are substantially the same as those of the first balloon 230. 【0098】 When using the imaging catheter 10, the operator inserts the guidewire GW, which has been introduced into blood vessel B prior to the imaging catheter 10, into the guidewire lumen 211 of the inner tube 210a of the shaft 210 of the second long body 200. By guiding the movement of the second long body 200 with the guidewire GW, the operator can also guide the movement of the first long body 100, which is connected to the second long body 200 via the balloons 230 and 240. The operator keeps the balloons 230 and 240 deflated while moving the imaging catheter 10 to the target site in blood vessel B (the site where the lesion is located). This prevents a decrease in the delivery efficiency of the imaging catheter 10 within blood vessel B. 【0099】 After the operator delivers the image acquisition unit 120, positioned near the distal end of the first elongated body 100, to the target site of blood vessel B, they inflate the balloons 230 and 240 as shown in Figures 4 and 5. By inflating the balloons 230 and 240, the operator can move the sheath 110 of the first elongated body 100, which is connected to each balloon 230 and 240, in the radial direction (including left, right, up, down, diagonal, etc., on the cross-sectional area perpendicular to the axis shown in Figure 4). In other words, when the balloons 230 and 240 are inflated, the distance between the axis O1 of the sheath 110 of the first elongated body 100 and the axis O2 of the shaft 210 of the second elongated body 200 increases, and the sheath 110 of the first elongated body 100 moves to a position closer to the blood vessel wall Bi of blood vessel B. 【0100】 The operator expands each balloon 230 and 240 to position the image acquisition unit 120 of the first elongated body 100 close to the vessel wall Bi of vessel B, and then rotates the handheld control unit 250 of the second elongated body 200 (for example, clockwise and / or counterclockwise), thereby rotating the first elongated body 100 circumferentially so that it follows the vessel wall Bi of vessel B, as shown in Figure 6. By rotating the first elongated body 100 circumferentially as described above, the operator can rotate the image acquisition unit 120 together with the sheath 110 of the first elongated body 100 circumferentially. 【0101】 The imaging catheter 10 has two balloons 230 and 240 on the second elongated body 200 connected to the outer surface of the sheath 110 of the first elongated body 100. In other words, the first elongated body 100 and the second elongated body 200 are connected to each other at two different axial positions where the balloons 230 and 240 are located. Therefore, when the balloons 230 and 240 are expanded, the sheath 110 can be smoothly moved radially in conjunction with the expansion of the balloons 230 and 240. Also, when the second elongated body 200 is rotated circumferentially by manual manipulation, the first elongated body 100 can be smoothly rotated circumferentially in conjunction with the rotation of the second elongated body 200. 【0102】 The operator can solve the following problems by positioning the image acquisition unit 120 in close proximity to the vessel wall Bi of vessel B, and then moving the image acquisition unit 120 circumferentially along the vessel wall Bi of vessel B while acquiring a tomographic image with the image acquisition unit 120. 【0103】 If the guidewire GW used to guide the image acquisition catheter 10 to the target position within blood vessel B is positioned close to the blood vessel wall Bi of blood vessel B, and as a result the image acquisition unit 120 is also positioned close to the blood vessel wall Bi of blood vessel B, then a so-called "frame-out" may occur, where the blood vessel wall on the opposite side of where the image acquisition unit 120 is positioned cannot be displayed on the tomographic image. This problem is particularly likely to occur when attempting to image relatively large lower limb arteries. Furthermore, in a rapid-exchange type catheter configuration in which the movement of the image acquisition catheter can be guided by inserting a guidewire GW through a portion of the distal end, the position and orientation of the distal end of the image acquisition catheter sheath 110 are greatly affected by the position of the guidewire GW. Therefore, when starting imaging, it may be unintentionally positioned close to one side of the blood vessel wall Bi of blood vessel B. Consequently, the above problem is even more likely to occur when a rapid-exchange type catheter configuration is used. To address the above issues, the image acquisition catheter 10 according to this embodiment allows for the acquisition of tomographic images while the image acquisition unit 120 is moved circumferentially while positioned in close proximity to the vessel wall Bi of the vessel B. Therefore, regardless of the initial position of the image acquisition unit 120 on the cross-section of the vessel B when imaging is started, it becomes possible to acquire a tomographic image of the entire vessel B. As a result, the vessel B, including the lesion, can be clearly displayed on the image display unit D without causing any loss of tomographic image of the vessel B. 【0104】 Furthermore, in catheters such as OCT catheters and OFDI catheters, which have a structure that irradiates light from the image acquisition unit 120 toward the vessel wall Bi of vessel B, if imaging is performed with the guidewire GW in close proximity to the vessel wall Bi of the vessel, the light irradiated from the image acquisition unit 120 is blocked by the guidewire GW, and a large shadow of the guidewire GW is projected onto the vessel wall Bi on the opposite side of where the guidewire GW is positioned. As a result, there is a possibility that a defect (a black area where the shadow is projected) may occur in part of the acquired tomographic image of the vessel wall Bi. The larger the diameter of the vessel, the larger the shadow that will be projected onto the opposite side, so the above problem is particularly likely to occur when attempting to image relatively large diameter lower limb arteries. In this embodiment, as described above, tomographic images can be acquired while moving the image acquisition unit 120 circumferentially along the vessel wall Bi of vessel B. Therefore, even if a guidewire GW is positioned between the vessel wall Bi of vessel B and the image acquisition unit 120, images of the vessel wall Bi on the side where the guidewire GW is positioned and the opposite side can be sequentially acquired along the circumferential direction of the vessel wall Bi of vessel B. This allows for a clear tomographic image of vessel B, including the lesion, to be displayed on the image display unit D without causing loss due to the shadow of the guidewire GW. 【0105】 As described above, the image acquisition catheter 10 according to this embodiment has a first elongated body 100 in which an image acquisition unit 120 for acquiring tomographic images of a biological lumen (for example, blood vessel B) is located at the distal end, and a second elongated body 200 which has expandable and contractible balloons 230 and 240 located at the distal end, and a proximal operating unit 250 located at the proximal end that enables proximal operation. The balloons 230 and 240 are connected to the outer surface near the distal end of the first elongated body 100, and the first elongated body 100 is configured to rotate in conjunction with the operation when the proximal operating unit 250 located at the proximal end of the second elongated body 200 is rotated along the circumferential direction of the biological lumen. 【0106】 With the image acquisition catheter 10 configured as described above, the image acquisition unit 120 can be smoothly moved radially and circumferentially on the cross-section of the biological lumen by operating to expand each balloon 230, 240 or by rotating it at the hand. This makes it possible to image lesions within the biological lumen more accurately. 【0107】 Next, a modified version of the above-described embodiment will be explained. In the explanation of the modified version, the same reference numerals will be used for components and parts already described, and their detailed explanations will be omitted. Furthermore, any parts not specifically mentioned in the explanation of the modified version may be the same as those in the above-described embodiment. 【0108】 <Variation> The image acquisition catheter 10 according to the above embodiment has a structure in which the first elongated body 100 and the second elongated body 200 are integrally connected via balloons (each balloon 230, 240) connected to the outer surface of the first elongated body 100 (see Figure 1). On the other hand, the modified image acquisition catheter 10A has a structure in which it is not integrally connected to balloons. 【0109】 As shown in Figure 1, the modified image acquisition catheter 10A comprises a long body 100A with an image acquisition unit 120 for acquiring tomographic images of blood vessel B located at its distal end, and housing units 310 and 320 provided on the outer surface of the distal end of the long body 100A, each equipped with lumens 315 and 325 capable of accommodating expandable and deflated balloons 230 and 240. 【0110】 Each housing section 310, 320 is configured to expand in accordance with the expansion of each balloon 230, 240 located within each lumen 315, 325. 【0111】 The balloon catheter 200A used with the image acquisition catheter 10A can be, for example, one having substantially the same configuration as the second elongated body 200 (see Figure 1) described in the above-described embodiment. In other words, the second elongated body 200 that is not connected to the elongated body 100A of the image acquisition catheter 10A can be used as the balloon catheter 200A. 【0112】 As shown in Figures 7 to 9, the elongated body 100A can be configured to include two or more housing sections 310, 320 spaced apart in the axial direction of the elongated body 100A. In this embodiment, the elongated body 100A includes two housing sections 310, 320 arranged at a predetermined distance apart in the axial direction of the elongated body 100A. 【0113】 As shown in Figures 8 and 9, the first housing section 310 is located distal to the second housing section 320 of the elongated body 100A. 【0114】 As shown in Figure 8, the first housing section 310 is composed of a cylindrical member comprising a distal section 311 having an opening that opens distally, a proximal section 313 having an opening that opens proximally, and a first lumen 315 that connects the distal section 311 and the proximal section 313. 【0115】 As shown in Figure 9, the second housing section 320 is composed of a cylindrical member comprising a distal section 321 having an opening that opens distally, a proximal section 323 having an opening that opens proximally, and a second lumen 325 that connects the distal section 321 and the proximal section 323. 【0116】 Each housing section 310, 320 can be made of, for example, a cylindrical member having substantially the same cross-sectional area along the axial direction. However, there are no particular restrictions on the external shape of each housing section 310, 320 or the cross-sectional shape of each lumen 315, 325. 【0117】 The image acquisition catheter 10A can be configured, similar to the first elongated body 100 in the embodiment described above, for example, by an IVUS catheter that uses ultrasound to acquire tomographic images, an OCT catheter (or OFDI catheter) that uses light of a predetermined wavelength, etc. 【0118】 The elongated body 100A of the image acquisition catheter 10A is composed of a sheath 110 of the first elongated body 100 according to the embodiment described above. The elongated body 100A has a lumen 115 that allows the image acquisition unit 120 to move in the axial direction. 【0119】 Each housing section 310, 320 is connected to the outer surface of the sheath 110 via each connecting section 117a, 117b. Each connecting section 117a, 117b can be made up of, for example, an adhesive that connects the sheath 110 to each housing section 310, 320, or a fused joint where the sheath 110 and each housing section 310, 320 are fused together. 【0120】 Each housing section 310, 320 is connected to the outer surface of the sheath 110 at a distal or proximal position within the range of movement of the image acquisition unit 120. 【0121】 In this modified example, the first connecting portion 117a, which connects the first housing portion 310 and the sheath 110, is positioned distal to the forward limit position P1. Furthermore, the second connecting portion 117b, which connects the second housing portion 320 and the sheath 110, is positioned proximal to the retraction limit position P2. 【0122】 Because the housing sections 310 and 320 are connected to the sheath 110 at the positions described above, when acquiring a tomographic image of blood vessel B using the image acquisition catheter 10A, it is possible to prevent the ultrasound or light emitted from the image acquisition unit 120 from being blocked by the balloons 230 and 240 located in the housing sections 310 and 320. As a result, even when a structure is adopted in which the housing sections 310 and 320 are connected to the outer surface of the sheath 110, it becomes possible to acquire a clear tomographic image with the image acquisition unit 120. 【0123】 Figure 7 shows the balloon catheter 200A with its first balloon 230 positioned in the first lumen 315 of the first housing 310, and its second balloon 240 positioned in the second lumen 325 of the second housing 320. In this figure, balloons 230 and 240 are shown in their expanded state. 【0124】 When acquiring a tomographic image of blood vessel B using the modified image acquisition catheter 10A, as shown in Figure 7, the respective balloons 230 and 240 placed within the respective housing sections 310 and 320 can be expanded, thereby expanding the housing sections 310 and 320 in conjunction with the expansion of the balloons 230 and 240. By expanding the housing sections 310 and 320 together with the balloons 230 and 240 in this way, the image acquisition catheter 10A can be moved radially on the cross-section of blood vessel B, similar to the embodiment described above (see Figure 5). 【0125】 Furthermore, by expanding the balloons 230 and 240 positioned within each housing section 310 and 320, each balloon 230 and 240 can be held or fixed to each housing section 310 and 320. This allows the balloon catheter 200A and the image acquisition catheter 10A to be connected via the balloons 230 and 240 and the housing sections 310 and 320. Therefore, with the balloons 230 and 240 expanded, the operator can rotate the balloon catheter 200A circumferentially along the vessel wall Bi of the vessel B, thereby smoothly rotating the image acquisition catheter 10A circumferentially, accompanying the balloon catheter 200A, similar to the embodiment described above (see Figure 6). 【0126】 As described above, by using the image acquisition catheter 10A according to this modified example, it is possible to effectively prevent issues such as frame-out and partial loss of tomographic images due to the reflection of the guidewire GW, similar to the embodiment described above. 【0127】 In the modified image acquisition catheter 10A, the balloon catheter 200A is prepared separately when the image acquisition catheter 10A is not in use (during storage or transport). Therefore, the operator only needs to consider and decide whether to use the balloon catheter 200A when starting to use the image acquisition catheter 10A. Thus, the use of the balloon catheter 200A is not mandatory when using the image acquisition catheter 10A. This helps to reduce the manufacturing costs of the image acquisition catheter 10A and the increase in medical costs associated with the use of the balloon catheter 200A. 【0128】 When using the imaging catheter 10A and balloon catheter 200A, the imaging catheter 10A and balloon catheter 200A can be prepared in a pre-assembled state. Specifically, the first balloon 230 in a deflated state is placed in the first housing section 310, and the second balloon 240 in a deflated state is placed in the second housing section 320. In this state, the distal end of the shaft 210 of the balloon catheter 200A is positioned to protrude distally from the first housing section 310. By assembling the balloon catheter 200A to the imaging catheter 10A in this way, the guidewire GW can be inserted into the shaft 210 using the guidewire lumen 211 and guidewire port 215 of the balloon catheter 200A. This allows the operator to assist in movement using the guidewire GW. Therefore, the imaging catheter 10A can be handled in the same way as a catheter device with a rapid exchange structure. 【0129】 Furthermore, the image acquisition catheter 10A and the balloon catheter 200A can also be provided as a catheter device in which both are assembled together. 【0130】 In other words, according to this modified example, a catheter device can be provided comprising an image acquisition catheter 10A, a balloon catheter 200A having balloons 230 and 240 distally positioned to be insertable into each lumen 315 and 325, and a proximal operating section 250 positioned to enable proximal operation, wherein the elongated body 100A is configured to rotate in conjunction with the operation of rotating the proximal operating section 250 along the circumferential direction of the blood vessel B when the balloons 230 and 240 positioned in each lumen 315 and 325 are expanded. 【0131】 The inner surfaces of each housing section 310, 320 and / or the outer surfaces of each balloon 230, 240 can be provided with coatings or structures (e.g., fine uneven surfaces) to increase the sliding resistance between each housing section 310, 320 and each balloon 230, 240. By adopting such a configuration, it becomes possible to increase the holding force (fixing force) between each housing section 310, 320 and each balloon 230, 240, thereby enabling more reliable and smoother radial movement of the image acquisition catheter 10A accompanying the expansion of the balloon catheter 200A and circumferential rotation of the image acquisition catheter 10A accompanying the rotation operation of the balloon catheter 200A. 【0132】 The materials constituting each housing section 310, 320 can be, for example, the same materials as those used for the sheath 110 as described above. However, the materials constituting each housing section 310, 320 are not particularly limited, as long as they can expand and contract in accordance with the expansion and contraction of each balloon 230, 240. 【0133】 Although the image acquisition catheter and catheter device according to the present invention have been described above through embodiments and modifications, the present invention is not limited to the configurations described in the embodiments and modifications, and can be modified as appropriate based on the claims. 【0134】 For example, the first elongated body 100 for acquiring tomographic images and the image acquisition unit 120 of the image acquisition catheter 10A are not limited to being configured to be movable in the axial direction of the sheath. As an example of such a configuration, an image acquisition catheter can be described in which the image acquisition unit 120 is configured to include a phased array type imaging core whose axial position of the sheath 110 is fixed. 【0135】 Furthermore, there are no particular restrictions on the number and specific location of balloons on the image acquisition catheter 10, the number and specific location of housings on the image acquisition catheter 10A, or the location and number of balloons on the balloon catheter 200A used together with the image acquisition catheter 10A; these can be changed as desired. For example, the number of balloons can be one or three or more, and the number of housings can also be one or three or more. 【0136】 Furthermore, the specific configurations of the image acquisition catheter, external drive unit, display device, and diagnostic imaging device are not limited to those described in the specification. Changes to the constituent materials of each component, the arrangement of each component, the omission of additional components, the addition of additional components, etc., can be made at will. [Explanation of symbols] 【0137】 1. Diagnostic imaging equipment 10. Catheter for image acquisition 10A Catheter for Image Acquisition 100 First Long Body 100A Long Body 110 Sheath 115 Lumen of the sheath 117a First connection section 117b Second connection section 119 Observation window 120 Image acquisition unit 130 Imaging shaft 140 Proximal Hub 200 Second Long Body 200A Balloon Catheter 210 shaft 210a inner tube 210b 1st outer tube 210c 2nd outer tube 211 guide wire lumens 212 Extended Lumens 215 Guidewire Port 230 First Balloon 240 Second Balloon 250 Handheld control unit 310 First Detention Unit 315 lumens 320 Second Detention Unit 325 2 lumens B blood vessels Bi blood vessel wall C Controller D Image display section GW Guidewire P1 forward limit position P2 Retraction limit position M External drive unit O1 Axis of the first elongated body O2 Axis of the second elongated body

Claims

[Claim 1] A first elongated body having an image acquisition unit for obtaining tomographic images of biological tubular lumen located at its distal end, It has a second elongated body comprising an expandable and deflated balloon located at the distal end, and a hand-operated control unit located at the proximal end for hand-operated operation, The balloon is connected to the outer surface near the distal portion of the first elongated body, The first elongated body is configured to rotate in conjunction with the operation of rotating the proximal operating section, which is located at the proximal end of the second elongated body, along the circumferential direction of the biological lumen, in an image acquisition catheter. [Claim 2] The second elongated body comprises two or more balloons spaced apart in the axial direction of the second elongated body, The image acquisition catheter according to claim 1, wherein each of the balloons is connected to the outer surface of the second elongated body. [Claim 3] The image acquisition catheter according to claim 1, wherein the first elongated body comprises an image acquisition unit having an ultrasonic receiving unit or an optical transmitting / receiving unit, and a sheath having a lumen from which the image acquisition unit can move. [Claim 4] The image acquisition catheter according to claim 3, wherein the balloon is connected to the outer surface of the sheath at a distal or proximal position within the range in which the image acquisition unit can move. [Claim 5] The image acquisition catheter according to claim 1, wherein the first elongated body and the second elongated body are separated from each other except at the connection point of the balloon. [Claim 6] A long body with an image acquisition unit located at its distal end for obtaining tomographic images of the biological lumen, The long body has a housing section provided on the outer surface of the distal end, which has a housing lumen capable of accommodating an expandable and deflated balloon, The aforementioned housing section is configured to expand in conjunction with the expansion of the balloon positioned within the housing lumen, and is an image acquisition catheter. [Claim 7] The image acquisition catheter according to claim 6, wherein the elongated body comprises two or more housing portions spaced apart in the axial direction of the elongated body. [Claim 8] The image acquisition catheter according to claim 6, wherein the elongated body is composed of a sheath having a lumen from which the image acquisition unit, which includes an ultrasonic receiving unit or an optical transmitting and receiving unit, can move. [Claim 9] The image acquisition catheter according to claim 8, wherein the housing portion is located in the sheath at a distal or proximal position within the range from which the image acquisition portion can move. [Claim 10] An image acquisition catheter according to any one of claims 6 to 9, A balloon catheter comprising a balloon distal to the balloon configured to be insertable into the aforementioned containment lumen, and a proximal control section positioned at the proximal end for manual operation, The elongated body is configured to rotate in conjunction with the operation of rotating the proximal operating section along the circumferential direction of the biological lumen when the balloon, which is positioned within the containment lumen, is expanded.

Images