Catheter for diagnostic imaging

Abstract

A catheter for diagnostic imaging according to the present disclosure comprises a driving shaft and an imaging core. The imaging core comprises an ultrasound transmission and reception unit, an optical transmission and reception unit, an optical transmission line, a holding body, and a housing. In the housing, there is formed an opening that allows the passage of the ultrasonic waves transmitted and received by the ultrasonic transmission and reception unit and the light transmitted and received by the optical transmission and reception unit. The ultrasonic transmission and reception unit and the holding body are respectively positioned relative to the housing in the catheter circumferential direction by edge portions on both sides in the catheter circumferential direction of the opening of the housing.

Description

Diagnostic imaging catheters

[0001] The present disclosure relates to diagnostic imaging catheters.

[0002] Diagnostic imaging catheters used to obtain images for diagnosing diseased sites and the like in a living body have been known for some time. As such diagnostic imaging catheters, development is underway for dual-type diagnostic imaging catheters that utilize both intravascular ultrasound (IVUS) and optical coherence tomography (OCT, or optical frequency domain imaging, or OFDI). Patent Document 1 discloses a dual-type diagnostic imaging catheter.

[0003] The diagnostic imaging catheter described in Patent Document 1 includes a sheath, a drive shaft, a housing provided at the tip of the drive shaft, an ultrasonic transmitter / receiver unit and an optical transmitter / receiver unit supported by the housing, and a positioning member that fixes the position of the optical transmitter / receiver unit relative to the ultrasonic transmitter / receiver unit. The housing described in Patent Document 1 also has an opening formed therein through which ultrasonic waves and light can pass.

[0004] International Publication No. 2019 / 004355

[0005] In the dual-type diagnostic imaging catheter described in Patent Document 1, the ultrasound transmitter-receiver and the optical transmitter-receiver are positioned relative to the housing so as to maintain a constant direction of light transmission from the optical transmitter-receiver relative to the direction of ultrasound transmission from the ultrasound transmitter-receiver. However, in the dual-type diagnostic imaging catheter described in Patent Document 1, when positioning the ultrasound transmitter-receiver and the optical transmitter-receiver relative to the housing, the positioning member is prone to rotate in the circumferential direction of the catheter relative to the housing. Therefore, the dual-type diagnostic imaging catheter described in Patent Document 1 still needs improvement in terms of ease of positioning the ultrasound transmitter-receiver and the optical transmitter-receiver relative to the housing while maintaining a desired positional relationship in the circumferential direction of the catheter between the ultrasound transmitter-receiver and the light transmitter-receiver.

[0006] The present disclosure aims to provide an imaging diagnostic catheter that can easily position the ultrasonic transmitter / receiver unit and the optical transmitter / receiver unit relative to the housing while maintaining the desired positional relationship around the catheter between the direction of transmission of ultrasonic waves from the ultrasonic transmitter / receiver unit and the direction of transmission of light from the optical transmitter / receiver unit.

[0007] A first aspect of the present disclosure provides a diagnostic imaging catheter: (1) A diagnostic imaging catheter comprising: a drive shaft; and an imaging core connected to the drive shaft, wherein the imaging core comprises: an ultrasonic transmitter / receiver; an optical transmitter / receiver; an optical transmission line connected to the optical transmitter / receiver; a holder that holds the optical transmission line; and a housing that supports the ultrasonic transmitter / receiver, the optical transmitter / receiver, and the holder, wherein an opening is formed in the housing through which ultrasonic waves transmitted and received by the ultrasonic transmitter / receiver and light transmitted and received by the optical transmitter / receiver can pass, and the ultrasonic transmitter / receiver and the holder are positioned in the circumferential direction of the catheter relative to the housing by edges on both sides of the opening in the housing in the circumferential direction of the catheter.

[0008] A diagnostic imaging catheter according to one embodiment of the present disclosure is the catheter for diagnostic imaging described in (1) above, wherein: (2) the opening of the housing is formed in a peripheral wall that defines an internal storage space capable of accommodating the ultrasound transmitting / receiving unit, the light transmitting / receiving unit, and the holder; the holder comprises a holding body that is accommodated in the storage space of the housing, and a protrusion that protrudes outward in the radial direction of the catheter from the holding body; and the edge portions on both sides of the opening are equipped with rotation restricting portions that sandwich the protrusion from both sides in the circumferential direction of the catheter and restrict rotation of the protrusion relative to the housing in the circumferential direction of the catheter.

[0009] A diagnostic imaging catheter according to one embodiment of the present disclosure is the diagnostic imaging catheter described in (2) above, wherein the rotation restricting portion includes a restricting portion that can restrict rotation of the catheter in the circumferential direction by abutting against the protruding portion of the holder, and a recess that is recessed from the restricting portion in the circumferential direction of the catheter.

[0010] A diagnostic imaging catheter according to one embodiment of the present disclosure is the diagnostic imaging catheter described in (2) or (3) above, wherein the edges on both sides of the opening are bridged so that the ultrasonic transmitter / receiver unit spans over them, and the catheter is provided with a support unit that supports the ultrasonic transmitter / receiver unit.

[0011] A diagnostic imaging catheter according to one embodiment of the present disclosure is the diagnostic imaging catheter described in (4) above, wherein the edge portions on both sides of the opening are provided with guide portions whose distance between them in the circumferential direction of the catheter gradually decreases from the distal side to the proximal side in the longitudinal direction of the catheter toward the rotation restricting portion.

[0012] A diagnostic imaging catheter according to one embodiment of the present disclosure is the catheter for diagnostic imaging described in any one of (2) to (5) above, wherein the protrusion has a groove formed on the outer surface of the catheter in the radial direction.

[0013] A diagnostic imaging catheter according to one embodiment of the present disclosure is the catheter for diagnostic imaging described in any one of (1) to (6) above, which includes an electric signal line connected to the ultrasound transmitting / receiving unit, and the holder has an insertion hole through which the electric signal line is inserted.

[0014] A diagnostic imaging catheter according to one embodiment of the present disclosure is the diagnostic imaging catheter described in (7) above, wherein the drive shaft is connected to the housing on the proximal side in the longitudinal direction of the catheter, and the optical transmission line and the electrical signal line extend within the drive shaft.

[0015] A diagnostic imaging catheter according to one embodiment of the present disclosure is: (9) The diagnostic imaging catheter according to any one of (1) to (8) above, wherein the opening of the housing extends to the distal end of the housing.

[0016] According to the present disclosure, it is possible to provide an imaging diagnostic catheter that can easily position the ultrasonic transmitter / receiver unit and the optical transmitter / receiver unit relative to the housing while maintaining the desired positional relationship around the catheter between the direction of transmission of ultrasonic waves from the ultrasonic transmitter / receiver unit and the direction of transmission of light from the optical transmitter / receiver unit.

[0017] 1 is a diagram showing an imaging diagnostic device including a diagnostic imaging catheter according to an embodiment of the present disclosure; FIG. 2 is a diagram showing the diagnostic imaging catheter alone shown in FIG. 1 , showing a state in which a probe and an inner tube are pushed in; FIG. 3 is a diagram showing the diagnostic imaging catheter alone shown in FIG. 1 , showing a state in which a probe and an inner tube are pulled out; FIG. 4 is a diagram showing a distal end of the diagnostic imaging catheter shown in FIG. 1; FIG. 5 is a perspective view of the vicinity of the imaging core shown in FIG. 3; FIG. 6 is a top view of the vicinity of the imaging core shown in FIG. 3; FIG. 7 is a diagram showing the positional relationship between the imaging core, the drive shaft, the electrical signal line, and the optical transmission line when the vicinity of the imaging core shown in FIG. 3 is viewed from the side of the imaging core; FIG. 8 is a cross-sectional view of the probe taken along a plane perpendicular to the longitudinal direction of the catheter at the position of the holder; FIG. 9 is a perspective view of the housing alone shown in FIG. 4; FIG. 10 is a flowchart showing an example of a method for manufacturing the diagnostic imaging catheter shown in FIG. 1; FIG. 11 is a diagram showing an overview of the retraction step shown in FIG.

[0018] Hereinafter, an embodiment of a catheter for diagnostic imaging according to the present disclosure will be described with reference to the drawings. In each drawing, the same components are designated by the same reference numerals.

[0019] Hereinafter, in this disclosure, the longitudinal direction of a diagnostic imaging catheter will be referred to as the "catheter longitudinal direction A." Hereinafter, in this disclosure, the tip side of a diagnostic imaging catheter that is inserted into a living body in the catheter longitudinal direction A will be referred to as the "distal side," and the proximal side of the catheter longitudinal direction A that is operated ex vivo and is opposite the distal side will be referred to as the "proximal side." Hereinafter, in this disclosure, the direction from the proximal side to the distal side of the diagnostic imaging catheter in the catheter longitudinal direction A will sometimes be simply referred to as the "insertion direction A1." Hereinafter, in this disclosure, the direction from the distal side to the proximal side of the diagnostic imaging catheter in the catheter longitudinal direction A will sometimes be simply referred to as the "removal direction A2."

[0020] In the following, in this disclosure, the circumferential direction around the central axis O of the drive shaft of the diagnostic imaging catheter will be referred to as the "catheter circumferential direction B." Furthermore, in the following, in this disclosure, the radial direction of an imaginary circle centered on the central axis O in an arbitrary cross-sectional view of the diagnostic imaging catheter that is perpendicular to the central axis O of the drive shaft will be referred to as the "catheter radial direction C."

[0021] Fig. 1 is a diagram showing an imaging diagnostic device 100 including a diagnostic imaging catheter 110 as one embodiment of the diagnostic imaging catheter according to the present disclosure. As shown in Fig. 1, the diagnostic imaging device 100 includes the diagnostic imaging catheter 110 and an external device 120. Fig. 1 shows a state in which the diagnostic imaging catheter 110 is connected to the external device 120.

[0022] 2A and 2B are diagrams showing the diagnostic imaging catheter 110 shown in FIG. 1 alone. As will be described in detail later, FIGS. 2A and 2B show different positions of the probe 10 in the catheter longitudinal direction A within the sheath 20. FIG. 3 is a diagram showing the distal end (hereinafter referred to as the "distal end") of the diagnostic imaging catheter 110. The diagnostic imaging catheter 110 is configured to acquire tomographic images of a lumen, such as a blood vessel. More specifically, the diagnostic imaging catheter 110 includes an ultrasound transceiver unit 61a for IVUS and an optical transceiver unit 61b for OCT / OFDI. As shown in FIG. 1, the diagnostic imaging catheter 110 is driven by being connected to an external device 120. More specifically, the diagnostic imaging catheter 110 of this embodiment is connected to a drive unit 120a of the external device 120.

[0023] 1 to 3, the diagnostic imaging catheter 110 of this embodiment includes a probe 10, a long sheath 20, an inner tube 30, and an outer tube 40. Each part of the diagnostic imaging catheter 110 of this embodiment will be described in detail below.

[0024] 3, the probe 10 includes an imaging core 60, a drive shaft 13, and an electric signal line 14a and an optical transmission line 14b extending within the drive shaft 13. The imaging core 60 of this embodiment includes an ultrasonic transmitter / receiver unit 61a, an optical transmitter / receiver unit 61b, a holder 61c, a housing 61d, and a protective member 61e.

[0025] Fig. 4 is a perspective view of the probe 10 near the imaging core 60. Fig. 5 is a top view of the probe 10 near the imaging core 60. For ease of explanation, the protective member 61e is omitted from Figs. 4 and 5. Fig. 6 is a diagram showing the positional relationship between the imaging core 60, the drive shaft 13, the electrical signal line 14a, and the optical transmission line 14b when the probe 10 near the imaging core 60 is viewed from the side of the imaging core 60. For ease of explanation, the housing 61d of the imaging core 60 is indicated by a dashed line in Fig. 6.

[0026] As shown in FIGS. 4 to 6 , the imaging core 60 is connected to the drive shaft 13. More specifically, the imaging core 60 of this embodiment is fixed to the distal end of the drive shaft 13. The ultrasound transmitting / receiving unit 61a of the imaging core 60 of this embodiment includes an ultrasound transducer 62. The ultrasound transducer 62 is capable of transmitting ultrasound waves based on a pulse signal into a cavity within a living body and receiving ultrasound waves reflected from biological tissue surrounding the cavity. The ultrasound transducer 62 of this embodiment includes a main body 62a and an electrode 62b. The main body 62a includes a piezoelectric element. The piezoelectric element includes a piezoelectric material such as ceramics or quartz. The ultrasound transmitting / receiving unit 61a can transmit and receive ultrasound waves using the ultrasound transducer 62. The ultrasound transmitting / receiving unit 61a is located distal to an optical element 61b1 (described later) of the optical transmitting / receiving unit 61b.

[0027] The optical transceiver 61b is capable of continuously transmitting the transmitted light into the lumen and continuously receiving the light reflected by the biological tissue surrounding the lumen. The optical transceiver 61b includes an optical element 61b1. The optical element 61b1 is connected to the distal end of the optical transmission line 14b and has a lens function for focusing light and a reflecting function for reflecting light.

[0028] The optical element 61b1 of this embodiment is a ball lens including a flat portion inclined with respect to the catheter longitudinal direction A and a spherical portion. The flat portion is coated with a reflective coating that reflects light propagating from the optical transmission line 14b. The material of the reflective coating is not particularly limited as long as it is capable of reflecting light, and examples thereof include aluminum. The light propagating from the optical transmission line 14b is reflected by the flat portion, collected by the spherical portion, and transmitted to the lumen. The light reflected by the biological tissue surrounding the lumen is collected by the spherical portion, reflected by the flat portion, and propagated to the optical transmission line 14b. In this way, the optical transceiver 61b can transmit and receive light via the optical element 61b1.

[0029] The holder 61c holds the optical transmission line 14b connected to the optical transceiver 61b. More specifically, the holder 61c of this embodiment holds the optical transmission line 14b, which is connected to the proximal side of the optical transceiver 61b, on the proximal side of the optical transceiver 61b in the catheter longitudinal direction A. The holder 61c may include, for example, a contrast marker portion that is radiopaque. Furthermore, the holder 61c may be, for example, a contrast marker member whose entire body is radiopaque. The radiopaque property of the holder 61c may be achieved by using a material that is highly radiopaque. Specifically, the holder 61c may include, for example, a material that is highly radiopaque, such as platinum, gold, iridium, or tungsten.

[0030] Fig. 7 is a cross-sectional view of the probe 10 taken along a plane perpendicular to the catheter longitudinal direction A at the position of the holder 61c. As shown in Fig. 7, the holder 61c is formed with a holding hole 61c3 through which the optical transmission line 14b is inserted in the catheter longitudinal direction A and which holds the optical transmission line 14b on its inner surface, and an insertion hole 61c4 through which the electrical signal line 14a is inserted in the catheter longitudinal direction A. In this embodiment, the holding hole 61c3 and the insertion hole 61c4 are each through-holes that pass through the holder 61c in the catheter longitudinal direction A, but may also be, for example, notches that open to the outer surface of the holder 61c in the catheter radial direction C.

[0031] The holder 61c of this embodiment is disposed proximal to the optical element 61b1 of the optical transmitter / receiver 61b. The holder 61c of this embodiment is fixed to the housing 61d. More specifically, the holder 61c of this embodiment is fixed to the housing 61d within a curved grooved plate portion 12b (described later) of the housing 61d. The optical transmission line 14b is inserted into a holding hole 61c3 of the holder 61c fixed to the housing 61d and is sandwiched by the inner surface defining the holding hole 61c3. This positions the optical transmitter / receiver 61b connected to the optical transmission line 14b within the housing 61d.

[0032] Also, as shown in Figure 7, the holding body 61c of this embodiment includes a holding main body 61c1 that is accommodated in the accommodation space 61d3 of the housing 61d, which will be described later, and a protrusion 61c2 that protrudes outward from this holding main body 61c1 in the catheter radial direction C.

[0033] The holding body 61c1 has a substantially cylindrical outer shape. In this embodiment, the holding hole 61c3 and the insertion hole 61c4 are formed in the holding body 61c1.

[0034] The protrusion 61c2 is positioned relative to the housing 61d by being sandwiched in the catheter circumferential direction B by edges on both sides of an opening 61d1 (described later) of the housing 61d in the catheter circumferential direction B. This will be described in detail later. Furthermore, the protrusion 61c2 of this embodiment includes a groove 63 formed on its outer surface in the catheter radial direction C. The groove 63 is formed to align with the position in the catheter circumferential direction B of the light transmitted from the optical transceiver 61b toward the outside in the catheter radial direction C. By providing such a groove 63, the alignment of the transmission direction of light from the optical transceiver 61b and the transmission direction of ultrasound from the ultrasound transceiver 61a in the catheter circumferential direction B can be easily performed from the outside by aligning the ultrasound transmitted from the ultrasound transceiver 61a with the groove 63, without actually transmitting light from the optical transceiver 61b.

[0035] The housing 61d directly or indirectly supports the ultrasound transceiver unit 61a, the optical transceiver unit 61b, and the holder 61c. The distal end of the drive shaft 13 is connected to the housing 61d. That is, the drive shaft 13 is connected to the proximal side of the housing 61d in the catheter longitudinal direction A. The housing 61d may be integrated with the drive shaft 13. Therefore, the housing 61d may be directly connected to the drive shaft 13 by adhesive or the like, or may be indirectly connected to the drive shaft 13 via a connector or the like.

[0036] FIG. 8 is a perspective view showing the housing 61d alone according to this embodiment. As shown in FIGS. 4 to 8 , the housing 61d has an opening 61d1. This opening 61d1 allows the passage of ultrasound transmitted and received by the ultrasound transmitting and receiving unit 61a and light transmitted and received by the optical transmitting and receiving unit 61b. That is, the ultrasound transmitting and receiving unit 61a can transmit ultrasound based on a pulse signal to the lumen through this opening 61d1. The ultrasound transmitting and receiving unit 61a can also receive ultrasound reflected from the biological tissue surrounding the lumen through this opening 61d1. The optical transmitting and receiving unit 61b can also transmit light to the lumen through this opening 61d1. The optical transmitting and receiving unit 61b can also receive light reflected from the biological tissue surrounding the lumen through this opening 61d1. As shown in FIG. 8 , the opening 61d1 of the housing 61d according to this embodiment is formed in a peripheral wall 70 that defines an internal storage space 61d3 capable of housing the ultrasound transmitting and receiving unit 61a, the optical transmitting and receiving unit 61b, and the holder 61c.

[0037] More specifically, as shown in FIG. 8 , the housing 61d of this embodiment includes a tubular portion 12a and a curved grooved plate portion 12b that is continuous with the tubular portion 12a on the distal side in the catheter longitudinal direction A. The curved grooved plate portion 12b is formed by extending only a portion of the peripheral wall of the tubular portion 12a in the catheter circumferential direction B toward the distal side in the catheter longitudinal direction A. In other words, the tubular portion 12a extends endlessly in the catheter circumferential direction B, whereas the curved grooved plate portion 12b does not extend endlessly in the catheter circumferential direction B. An opening 61d1 is formed between both end faces 15 of the curved grooved plate portion 12b in the catheter circumferential direction B. In other words, in this embodiment, both edges of the opening 61d1 in the catheter circumferential direction B are defined by both end faces 15 of the curved grooved plate portion 12b in the catheter circumferential direction B.

[0038] The cylindrical portion 12a constitutes the proximal end of the housing 61d. In this embodiment, the cylindrical portion 12a is located proximal to the ultrasound transceiver 61a, the optical transceiver 61b, and the holder 61c. The drive shaft 13 is connected to the cylindrical portion 12a of the housing 61d. In addition, the curved grooved plate portion 12b in this embodiment constitutes the distal end of the housing 61d. In other words, the opening 61d1 of the housing 61d in this embodiment extends to the distal end 61d2 of the housing 61d.

[0039] 4, 5, and 7, the ultrasonic transmitter / receiver 61a and the holder 61c are positioned in the catheter circumferential direction B relative to the housing 61d by the edges of the opening 61d1 of the housing 61d on both sides in the catheter circumferential direction B. Therefore, the ultrasonic transmitter / receiver 61a and the optical transmitter / receiver 61b can be easily positioned relative to the housing 61d while maintaining a desired positional relationship in the catheter circumferential direction B between the direction of transmission of ultrasonic waves from the ultrasonic transmitter / receiver 61a and the direction of transmission of light from the optical transmitter / receiver 61b.

[0040] More specifically, the curved grooved plate 12b of this embodiment includes a distal portion 12b1 having an arc-shaped or substantially U-shaped outer shape in a cross section perpendicular to the catheter longitudinal direction A, and a proximal portion 12b2 having a substantially C-shaped outer shape in a cross section perpendicular to the catheter longitudinal direction A. The proximal portion 12b2 is located more proximal in the catheter longitudinal direction A than the distal portion 12b1.

[0041] The opening 61d1 described above is formed over the entire region in which the curved grooved plate portion 12b is located in the catheter longitudinal direction A. However, in this embodiment, the width of the opening 61d1 in the catheter circumferential direction B varies depending on the position in the catheter longitudinal direction A. Specifically, in this embodiment, the width of the opening 61d1 in the catheter circumferential direction B at the position of the distal portion 12b1 in the catheter longitudinal direction A is wider than the width of the opening 61d1 in the catheter circumferential direction B at the position of the proximal portion 12b2 in the catheter longitudinal direction A. In this embodiment, the width of the opening 61d1 in the catheter circumferential direction B refers to the central angle of the opening 61d1 with the central axis O as its center.

[0042] The distal portion 12b1 supports the ultrasonic transmitter / receiver 61a. Specifically, the ultrasonic transmitter / receiver 61a spans both edge portions of the opening 61d1 in the catheter circumferential direction B and is supported by these both edge portions. As described above, in this embodiment, both edge portions of the opening 61d1 in the catheter circumferential direction B are formed by both end surfaces 15 of the curved grooved plate portion 12b in the catheter circumferential direction B. In other words, the ultrasonic transmitter / receiver 61a in this embodiment is supported by both end surfaces 15a of the distal portion 12b1, out of both end surfaces 15 of the curved grooved plate portion 12b.

[0043] More specifically, the distal section 12b1 of this embodiment supports the ultrasonic transmitter / receiver unit 61a via a backing member 80. The backing member 80 scatters and attenuates ultrasonic waves traveling from the ultrasonic transmitter / receiver unit 61a in the direction opposite the opening 61d1 of the housing 61d. The method for fixing the backing member 80 to the distal section 12b1 is not particularly limited. For example, the backing member 80 may be fixed to the distal section 12b1 by adhesive bonding. The backing member 80 of this embodiment supports the ultrasonic transmitter / receiver unit 61a so that the ultrasonic transmitter / receiver unit 61a can transmit ultrasonic waves in a direction oblique to the catheter longitudinal direction A. More specifically, the backing member 80 of this embodiment is supported by the end surface 15a of the distal section 12b1, which extends obliquely with respect to the catheter longitudinal direction A. As a result, the ultrasonic transmitter / receiver unit 61a supported by the backing member 80 is in a state of being oblique with respect to the catheter longitudinal direction A. Therefore, the ultrasonic transmitter / receiver unit 61a of this embodiment can transmit ultrasonic waves in a direction oblique to the catheter longitudinal direction A.

[0044] The proximal portion 12b2 also supports a holding body 61c. More specifically, the holding body 61c includes a holding body 61c1 having a generally cylindrical outer shape and a protruding portion 61c2 that protrudes outward in the catheter radial direction C from the holding body 61c1. The proximal portion 12b2 accommodates the holding body 61c1 in an internal accommodation space 61d3. The protruding portion 61c2 of the holding body 61c protrudes so as to fit into the opening 61d1 when the holding body 61c1 of the holding body 61c is accommodated in the internal accommodation space 61d3 of the proximal portion 12b2. Therefore, the protruding portion 61c2 is restricted from rotating in the catheter circumferential direction B relative to the housing 61d by the edges on both sides of the opening 61d1 in the catheter circumferential direction B. As described above, in this embodiment, the edges on both sides of the opening 61d1 in the catheter circumferential direction B are formed by both end faces 15 of the curved grooved plate portion 12b in the catheter circumferential direction B. In other words, the rotation of the protruding portion 61c2 of the holding body 61c in this embodiment is restricted by both end faces 15b of the proximal portion 12b2 of both end faces 15 of the curved grooved plate portion 12b. In this way, the proximal portion 12b2 supports the holding body 61c.

[0045] As described above, in this embodiment, the ultrasonic transmitter / receiver 61a is positioned in the catheter circumferential direction B with respect to the housing 61d by both end faces 15a of the distal portion 12b1, which serve as edges on both sides of the opening 61d1 of the housing 61d in the catheter circumferential direction B. Also, in this embodiment, the holder 61c is positioned in the catheter circumferential direction B with respect to the housing 61d by both end faces 15b of the proximal portion 12b2, which serve as edges on both sides of the opening 61d1 of the housing 61d in the catheter circumferential direction B. Therefore, the ultrasonic transmitter / receiver 61a and the optical transmitter / receiver 61b can be easily positioned with respect to the housing 61d while maintaining a desired positional relationship in the catheter circumferential direction B between the direction of ultrasonic transmission from the ultrasonic transmitter / receiver 61a and the direction of light transmission from the optical transmitter / receiver 61b.

[0046] More specifically, as shown in Figure 8, both end faces 15 of the curved grooved plate portion 12b, which serve as the edge portions on both sides of the opening 61d1 of the housing 61d in this embodiment in the catheter circumferential direction B, are provided with a rotation control portion 16, a support portion 17, and a guide portion 18.

[0047] The rotation restricting portion 16 is configured to sandwich the protruding portion 61c2 of the holder 61c from both sides in the catheter circumferential direction B and to restrict rotation of the protruding portion 61c2 relative to the housing 61d in the catheter circumferential direction B by abutting against the protruding portion 61c2. As described above, the rotation restricting portion 16 of this embodiment is formed by both end surfaces 15b of the proximal portion 12b2 of the curved grooved plate portion 12b.

[0048] The support portion 17 is bridged by the ultrasonic transmitter / receiver unit 61a so as to be able to support the ultrasonic transmitter / receiver unit 61a. The support portion 17 of this embodiment is located distal to the rotation restricting unit 16 in the catheter longitudinal direction A. As described above, the support portion 17 of this embodiment is formed by both end faces 15a of the distal portion 12b1 of the curved grooved plate portion 12b. In this embodiment, both end faces 15a of the distal portion 12b1 extend substantially parallel to each other and are included in the same plane. By being supported in a state in which it is bridged across both end faces 15a of the distal portion 12b1, the ultrasonic transmitter / receiver unit 61a is positioned so as not to rotate in the catheter circumferential direction B with respect to the housing 61d.

[0049] The guide portions 18 are configured such that the distance between them in the catheter circumferential direction B gradually decreases from the distal side to the proximal side in the catheter longitudinal direction A toward the rotation restricting portion 16. The guide portion 18 is located between the rotation restricting portion 16 and the support portion 17 in the catheter longitudinal direction A. The proximal end of the guide portion 18 is continuous with the distal end of the rotation restricting portion 16. Like the rotation restricting portion 16, the guide portion 18 of this embodiment is formed by both end surfaces 15b of the proximal portion 12b2 of the curved grooved plate portion 12b described above. When the holding body 61c is fixed to the housing 61d, the protrusion 61c2 passes between the guide portions 18 and moves from the distal side to the proximal side in the catheter longitudinal direction A to a position between the rotation restricting portions 16. At this time, the protrusion 61c2 is guided in its movement direction by abutting against the guide portion 18. Therefore, by providing the guide portion 18, the protrusion 61c2 can be easily moved to a position between the rotation restriction portions 16.

[0050] As described above, the rotation restricting portion 16 and the guide portion 18 in this embodiment are each formed by both end surfaces 15b of the proximal portion 12b2 of the curved grooved plate portion 12b in the catheter circumferential direction B. More specifically, the portion of the end surface 15b of the proximal portion 12b2 in the catheter circumferential direction B that forms the rotation restricting portion 16 includes a restricting portion 15b1 that extends substantially parallel to the catheter longitudinal direction A and abuts against the protruding portion 61c2 of the holding body 61c to restrict rotation of the protruding portion 61c2 in the catheter circumferential direction B relative to the housing 61d, and a recess 15b2 that is recessed from the restricting portion 15b1 in the catheter circumferential direction B. The provision of such a recess 15b2 makes it easier to fill an adhesive or the like into the storage space 61d3 inside the proximal portion 12b2 through the recess 15b2. That is, according to the end surface 15b of the proximal portion 12b2 of this embodiment, the restricting portion 15b1 restricts rotation of the protruding portion 61c2 of the holding body 61c in the catheter circumferential direction B, while the recessed portion 15b2 makes it easier to fill the accommodation space 61d3 inside the proximal portion 12b2 with adhesive for fixing the holding body 61c1 to the proximal portion 12b2. As in this embodiment, it is preferable that the end surface 15b includes both the restricting portion 15b1 located distal to the recessed portion 15b2 and the restricting portion 15b1 located proximal to the recessed portion 15b2. This more reliably ensures space within the recessed portion 15b2 as an adhesive filling port.

[0051] As described above, the support section 17 of this embodiment is formed by both end faces 15a of the distal section 12b1 in the catheter circumferential direction B. More specifically, both end faces 15a of the distal section 12b1 of this embodiment extend at an angle with respect to the catheter longitudinal direction A so that the width of the opening 61d1 in the catheter circumferential direction B gradually increases from the distal side to the proximal side in the catheter longitudinal direction A. However, both end faces 15a of the distal section 12b1 may extend, for example, substantially parallel to the catheter longitudinal direction A.

[0052] In this embodiment, both edge portions of the opening 61d1 of the housing 61d in the catheter circumferential direction B are provided with abutting portions 19 in addition to the rotation restricting portion 16, support portion 17, and guide portion 18 described above. The abutting portions 19 face the distal side in the catheter longitudinal direction A and are configured to be able to abut against the ultrasound transmitting and receiving unit 61a supported by the support portion 17. The ultrasound transmitting and receiving unit 61a is positioned in the catheter longitudinal direction A by abutting against the abutting portions 19. The abutting portions 19 are configured by a stepped surface 15c that connects the end face 15a in the catheter circumferential direction B of the distal portion 12b1 and the end face 15b in the catheter circumferential direction B of the proximal portion 12b2, both of the end faces 15 of the curved grooved plate portion 12b.

[0053] The housing 61d may be formed by, for example, cutting out a metal block or by metal injection molding (MIM).

[0054] The protective member 61e is attached to the housing 61d so as to cover the distal end 61d2 of the housing 61d. The protective member 61e includes a main body portion 61e1 having a substantially hemispherical outer shape and a fixing portion 61e2 connected to the proximal side of the main body portion 61e1 and fixed to the distal portion 12b1 of the curved grooved plate portion 12b. The fixing portion 61e2 may be, for example, a cylindrical portion fixed to the concave inner surface of the distal portion 12b1 by adhesive or the like. The provision of the protective member 61e reduces friction and snagging with the inner surface of the sheath 20, thereby preventing damage to the sheath 20 caused by the housing 61d. The protective member 61e of this embodiment may be made of, for example, a resin material. The protective member 61e may also include, for example, a coil. The protective member 61e may also be, for example, a resin tube member that is fitted onto and fixed to the distal portion 12b1 of the curved grooved plate portion 12b of the housing 61d.

[0055] 2A, 2B, and 3, the drive shaft 13 extends through the inside of the sheath 20, the inner tube 30, and the outer tube 40. As described above, the distal end of the drive shaft 13 is connected to the housing 61d of the imaging core 60. The proximal end of the drive shaft 13 is held by the hub 32 (described below) that constitutes the proximal end of the inner tube 30.

[0056] As shown in FIGS. 3 to 6 , the electric signal line 14a is connected to the ultrasonic transmitter / receiver unit 61a. As shown in FIGS. 3 and 6 , the electric signal line 14a extends within the drive shaft 13. The electric signal line 14a electrically connects the ultrasonic transmitter / receiver unit 61a of the imaging core 60 to the external device 120 (see FIG. 1 ). A plurality of electric signal lines 14a (two in this embodiment) are provided, and as shown in FIGS. 4 to 6 , each electric signal line 14a is connected to an electrode 62b of the ultrasonic transmitter / receiver unit 61a of the imaging core 60. The connection between each electric signal line 14a and the electrode 62b may be performed by, for example, soldering. The plurality of electric signal lines 14a may be formed, for example, by a twisted pair cable in which two electric signal lines 14a are twisted together. Each electric signal line 14a may be a flexible thin wire member having an outer diameter greater than 0 mm and equal to or less than 0.1 mm. Each of the electric signal lines 14a can be configured, for example, by a conductor and a covering material made of an insulating material that covers the conductor.

[0057] 3 and 6, the optical transmission line 14b extends inside the drive shaft 13. The optical transmission line 14b optically connects the optical transmitter / receiver 61b of the imaging core 60 to the external device 120 (see FIG. 1). As shown in FIGS. 3 to 6, the optical transmission line 14b is connected to the optical element 61b1 of the optical transmitter / receiver 61b of the imaging core 60. The optical transmission line 14b includes, for example, an optical fiber as an optical transmission path.

[0058] [Sheath 20] The sheath 20 is an elongated member inserted into a lumen such as a blood vessel. As shown in Figures 2A, 2B, and 3, the sheath 20 includes a main body 20a and a guidewire insertion portion 20b. A first hollow portion 21a is defined inside the main body 20a. A second hollow portion 21b is defined in the guidewire insertion portion 20b. The first hollow portion 21a of the main body 20a houses the probe 10. The probe 10 can move back and forth in the first hollow portion 21a in the catheter longitudinal direction A. A guidewire W can be inserted into the second hollow portion 21b of the guidewire insertion portion 20b. As shown in Figure 3, the guidewire insertion portion 20b may be provided with a contrast marker portion 23 that is radiopaque. The contrast marker portion 23 can be formed of, for example, a metal pipe or metal coil having high radiopacity, such as platinum, gold, iridium, or tungsten. In this embodiment, as shown in Fig. 3, the tubular guidewire insertion portion 20b is adjacent to the distal end of the tubular main body portion 20a so as to be parallel to each other. The main body portion 20a and the guidewire insertion portion 20b may be formed by joining different tubular members together by heat fusion or the like.

[0059] In this embodiment, a communication hole 22a1 that connects the inside and outside of the first hollow portion 21a is formed at the distal end of the main body 20a. A reinforcing member 22 for firmly joining and supporting the guidewire insertion portion 20b is provided at the distal end of the main body 20a. A communication passage 22a that connects the inside of the first hollow portion 21a, which is located proximal to the reinforcing member 22, with the communication hole 22a1 is formed in the reinforcing member 22. However, the reinforcing member 22 does not necessarily have to be provided at the distal end of the main body 20a.

[0060] The communication hole 22a1 is a priming solution discharge hole for discharging the priming solution. When the diagnostic imaging catheter 110 is used, a priming process is performed in which the priming solution is filled into the main body 20a of the sheath 20. When performing the priming process, the priming solution is discharged to the outside through the communication hole 22a1, and gas such as air can be discharged from the main body 20a of the sheath 20 together with the priming solution.

[0061] The sheath 20 and the reinforcing member 22 are preferably formed of a flexible material, but the material is not particularly limited. Examples of the constituent materials include 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 elastomers. Combinations of one or more of these (polymer alloys, polymer blends, laminates, etc.) may also be used. The outer surface of the sheath 20 may also be provided with a hydrophilic lubricating coating layer that exhibits lubricity when wet.

[0062] [Inner Tube 30 and Outer Tube 40] The inner tube 30 accommodates the proximal end of the drive shaft 13 and is movable within the outer tube 40 together with the drive shaft 13. As shown in Figures 1, 2A, and 2B, the inner tube 30 includes an inner tube body 31 and a hub 32. The inner tube body 31 is inserted within the outer tube 40 so as to be movable back and forth. The hub 32 is connected to the proximal side of the inner tube body 31.

[0063] 1 , 2A, and 2B , the outer tube 40 is fixed to the proximal end of the sheath 20. The outer tube 40 of this embodiment includes an outer tube main body 41, a distal connector 42, and a proximal connector 43. The outer tube main body 41 is located radially outside the inner tube main body 31, and the inner tube main body 31 moves back and forth within the outer tube main body 41. The distal connector 42 connects the proximal end of the main body 20a of the sheath 20 to the distal end of the outer tube main body 41. The proximal connector 43 is fixed to the proximal end of the outer tube main body 41.

[0064] The drive shaft 13, the electrical signal line 14a, and the optical transmission line 14b of the probe 10 described above extend from the main body 20a of the sheath 20, through the outer tube 40 connected to the proximal side of the main body 20a, to the hub 32 that constitutes the proximal end of the inner tube 30.

[0065] The probe 10 and inner tube 30 are connected to each other so that they can integrally move forward and backward in the catheter longitudinal direction A. Therefore, for example, when the inner tube 30 is pushed in the insertion direction A1, the inner tube 30 is pushed into the outer tube 40 in the insertion direction A1. When the inner tube 30 is pushed into the outer tube 40 in the insertion direction A1, the probe 10 connected to the inner tube 30 moves in the insertion direction A1 within the main body portion 20a of the sheath 20. This results in the pushed-in state shown in FIG. 2A. When the inner tube 30 is pulled in the withdrawal direction A2 from the pushed-in state shown in FIG. 2A, the inner tube 30 is withdrawn from the outer tube 40 in the withdrawal direction A2. When the inner tube 30 is withdrawn from the outer tube 40 in the withdrawal direction A2, the probe 10 connected to the inner tube 30 moves in the withdrawal direction A2 within the main body portion 20a of the sheath 20. This results in the withdrawn state shown in FIG. 2B.

[0066] 2A , when the inner tube 30 is pushed in the insertion direction A1 to the maximum, the distal end of the inner tube 30 reaches near the distal connector 42 of the outer tube 40. At this time, the imaging core 60 of the probe 10 is located near the distal end of the main body 20 a of the sheath 20.

[0067] 1, the external device 120 includes a motor 121 that is a power source for rotating the drive shaft 13 (see FIG. 2A etc.), and a motor 122 that is a power source for moving the drive shaft 13 in the catheter longitudinal direction A. The rotational motion of the motor 122 is converted into axial motion by a ball screw 123 connected to the motor 122.

[0068] More specifically, the external device 120 of this embodiment includes a drive unit 120a, a control device 120b electrically connected to the drive unit 120a by wire or wirelessly, and a monitor 120c capable of displaying an image generated by the control device 120b based on ultrasonic and optical reception signals received from the diagnostic imaging catheter 110. The motor 121, motor 122, and ball screw 123 described above of this embodiment are provided in the drive unit 120a. The operation of this drive unit 120a is controlled by the control device 120b. The control device 120b includes a processor such as a CPU.

[0069] The external device 120 is not limited to the configuration shown in this embodiment, and may further include an external input unit such as a keyboard.

[0070] <<Opening 61d1 of Housing 61d of Imaging Core 60 of Diagnostic Imaging Catheter 110>> Hereinafter, with reference to FIGS. 3 to 8, the opening 61d1 of the housing 61d of the imaging core 60 of the diagnostic imaging catheter 110 of this embodiment will be described in further detail.

[0071] As described above, the housing 61d supports the ultrasonic transmitter / receiver 61a, the optical transmitter / receiver 61b, and the holder 61c. The housing 61d also has an opening 61d1 through which the ultrasonic waves transmitted and received by the ultrasonic transmitter / receiver 61a and the light transmitted and received by the optical transmitter / receiver 61b can pass. As shown in Figures 3 to 6, the opening 61d1 in this embodiment is formed at a position adjacent to the ultrasonic transmitter / receiver 61a and the optical transmitter / receiver 61b in the catheter radial direction C.

[0072] The opening 61d1 extends to the distal end 61d2 of the housing 61d, allowing the ultrasonic transmitter / receiver 61a to pass through from the distal end 61d2 of the housing 61d toward the proximal side. That is, the ultrasonic transmitter / receiver 61a can move, in part or in whole, from the distal opening end of the opening 61d1 toward the proximal side to a support position on the distal portion 12b1 of the curved grooved plate portion 12b of the housing 61d by passing through the opening 61d1. More specifically, the ultrasonic transmitter / receiver 61a of this embodiment can move from the distal end 61d2 of the housing 61d toward the proximal side through the groove on the inner side of the approximately semi-cylindrical distal portion 12b1 and through the opening 61d1 formed at a position opposite the distal portion 12b1 in the catheter radial direction C. In this way, by configuring the opening 61d1 to extend to the distal end 61d2 of the housing 61d, even if the housing 61d is made smaller, the ultrasonic transmission / reception unit 61a can be moved from the distal end 61d2 of the housing 61d to the proximal side, i.e., in the removal direction A2, through the opening 61d1, and the ultrasonic transmission / reception unit 61a can be positioned at a predetermined support position of the housing 61d.

[0073] Therefore, even in the diagnostic imaging catheter 110 including the ultrasonic transmitting / receiving unit 61a and the optical transmitting / receiving unit 61b, the housing 61d can be made compact, and the ultrasonic transmitting / receiving unit 61a to which the electric signal line 14a is connected in advance can be easily attached to the housing 61d. Details of this will be described later (see FIG. 10).

[0074] 4 to 7, the imaging core 60 also includes a holder 61c that supports the optical transmission line 14b within the housing 61d. As described above, the holder 61c is formed with a holding hole 61c3 through which the optical transmission line 14b is inserted and held, and an insertion hole 61c4 through which the electrical signal line 14a is inserted. In other words, the holder 61c is fixed to the optical transmission line 14b by inserting the optical transmission line 14b into the holding hole 61c3.

[0075] In this embodiment, the ultrasonic transmitter / receiver 61a is disposed at a position that does not overlap with the optical transmitter / receiver 61b in a plan view of the housing 61d from the opening 61d1 side (top view in FIG. 5 ), but is not limited to this configuration. The ultrasonic transmitter / receiver 61a may be disposed at a position that partially overlaps with the optical transmitter / receiver 61b in a plan view of the housing 61d from the opening 61d1 side (top view in FIG. 5 ).

[0076] 4 and 8 , the housing 61d includes a curved grooved plate 12b at a position in the catheter longitudinal direction A where the opening 61d1 is formed. The ultrasonic transmitter / receiver 61a is supported by both end faces 15a in the catheter circumferential direction B of the distal portion 12b1 of the curved grooved plate 12b of the housing 61d. More specifically, the ultrasonic transmitter / receiver 61a of this embodiment is indirectly supported by both end faces 15a because the backing member 80 that supports the ultrasonic transmitter / receiver 61a is directly supported by both end faces 15a. In this manner, the ultrasonic transmitter / receiver 61a is configured to be supported by both end faces 15a of the distal portion 12b1 of the housing 61d, making it easier to position the ultrasonic transmitter / receiver 61a relative to the housing 61d in the catheter circumferential direction B. Furthermore, by configuring the backing member 80 to be supported by both end faces 15a, a wider support surface for supporting the ultrasonic transmitter / receiver unit 61a of the backing member 80 can be ensured compared to a configuration in which the backing member 80 is not supported by both end faces 15a but is supported only in the groove of the distal portion 12b1. Therefore, a wider surface area can be ensured for the main body portion 62a of the ultrasonic transmitter / receiver unit 61a that is supported on the support surface of the backing member 80.

[0077] Furthermore, in a configuration in which the ultrasonic transmitting / receiving unit 61a is supported on both end surfaces 15a of the distal portion 12b1 of the curved grooved plate portion 12b of the housing 61d, as in the present embodiment, it is particularly advantageous that the opening 61d1 extends to the distal end 61d2 of the housing 61d, as described above, and that the ultrasonic transmitting / receiving unit 61a is configured to be able to pass from the distal end 61d2 of the housing 61d toward the proximal side. If the distal end of the housing 61d were formed in a cylindrical shape with the same inner and outer diameters as the cylindrical portion 12a, the backing member 80 supported on both end surfaces 15a would not be able to be retracted into the housing 61d from the cylindrical distal end of the housing 61d toward the proximal side. This is because the backing member 80 would get caught on the cylindrical distal end of the housing 61d. Therefore, by providing the opening 61d1 that is open on the distal side as described above, it is possible to prevent the backing member 80 from getting caught as described above, and to retract the backing member 80 into the housing 61d from the distal end 61d2 of the housing 61d toward the proximal side.

[0078] Next, an example of a manufacturing method for the diagnostic imaging catheter 110 according to the present disclosure will be described with reference to Figures 9 and 10. Figure 9 is a flowchart showing an example of the manufacturing method for the diagnostic imaging catheter 110. The manufacturing method shown in Figure 9 includes an attachment step S1, an insertion step S2, a retraction step S3, a holder positioning step S4, a support step S5, and a protection step S6. Figure 10 is a diagram showing an overview of the retraction step S3, in which the ultrasound transceiver unit 61a and the optical transceiver unit 61b are retracted and installed into a housing 61d connected to the distal end of the drive shaft 13.

[0079] 10 , in the retracting step S3, the ultrasonic transmitter / receiver unit 61a, to which the electric signal line 14a is connected, is retracted proximally from the distal end 61d2 of the housing 61d through the opening 61d1 extending to the distal end 61d2 of the housing 61d. In other words, the ultrasonic transmitter / receiver unit 61a is not installed in the housing 61d by moving it only in the catheter radial direction C, but is instead moved in the catheter longitudinal direction A through the opening 61d1 and installed in the housing 61d. This method allows the ultrasonic transmitter / receiver unit 61a to be retracted into the housing 61d with the electric signal line 14a connected, even if a housing 61d is used that is compact and has limited installation space for the ultrasonic transmitter / receiver unit 61a due to the need to also install the optical transmitter / receiver 61b. Conventionally, when using a housing that is not only compact but also requires the installation of an optical transceiver 61b, the electrical signal line 14a is placed inside the housing beforehand, and then the ultrasonic transceiver 61a is moved through the opening 61d1 in the catheter radial direction C and installed inside the housing. Since the ultrasonic transceiver 61a and the electrical signal line 14a must be connected inside the compact housing, the connection of the ultrasonic transceiver 61a and the electrical signal line 14a is difficult. In contrast, by employing the retracting step S3 described above, it is possible to reduce the size of the housing 61d while improving the ease of attaching the ultrasonic transceiver 61a and the optical transceiver 61b to the housing 61d.

[0080] In the retracting step S3, the ultrasonic transmitter / receiver 61a connected to the electric signal line 14a may be retracted from the distal end 61d2 of the housing 61d toward the proximal side through the opening 61d1, with the optical transmitter / receiver 61b being supported in advance by the housing 61d. However, as shown in Fig. 10, the ultrasonic transmitter / receiver 61a connected to the electric signal line 14a may also be retracted from the distal end 61d2 of the housing 61d toward the proximal side through the opening 61d1 together with the optical transmitter / receiver 61b connected to the optical transmission line 14b.

[0081] 9 , before executing the retracting step S3, it is preferable to execute an attachment step S1 of attaching the holder 61c to the optical transmission line 14b and an insertion step S2 of inserting the electric signal line 14a into the insertion hole 61c4 of the holder 61c. In the attachment step S1 of this embodiment, the optical transmission line 14b is inserted into the holding hole 61c3 of the holder 61c. This allows the holder 61c to be attached to the optical transmission line 14b. Thereafter, in the retracting step S3, it is preferable to retract the ultrasonic transmitter / receiver 61a connected to the electric signal line 14a, together with the optical transmitter / receiver 61b connected to the optical transmission line 14b and the holder 61c attached to the optical transmission line 14b, from the distal end 61d2 of the housing 61d toward the proximal side through the opening 61d1. In this way, in addition to the ultrasound transmitting / receiving unit 61a connected to the electric signal line 14a and the optical transmitting / receiving unit 61b connected to the optical transmission line 14b, the holder 61c attached to the optical transmission line 14b with the electric signal line 14a inserted through the insertion hole 61c4 can be pulled into the housing 61d together, thereby further improving the manufacturing efficiency of the diagnostic imaging catheter 110.

[0082] In the holder positioning step S4, the holder 61c, which has been retracted proximally from the distal end 61d2 of the housing 61d, is supported by the proximal portion 12b2 of the curved grooved plate portion 12b of the housing 61d. Specifically, while the holding body 61c1 of the holder 61c is accommodated in the accommodation space 61d3 inside the proximal portion 12b2, the protruding portion 61c2 of the holder 61c is moved from between the guide portions 18 (see FIG. 8) to a position between the rotation restricting portions 16 (see FIG. 8). As a result, the holding body 61c1 of the holder 61c is accommodated in the accommodation space 61d3, and the rotation of the protruding portion 61c2 of the holder 61c in the catheter circumferential direction B is restricted by both end faces 15b of the proximal portion 12b2. In other words, the holder 61c can be positioned with respect to the housing 61d without rotating in the catheter circumferential direction B relative to the housing 61d.

[0083] In the supporting step S5, the ultrasonic transmitter / receiver unit 61a, which has been retracted proximally from the distal end 61d2 of the housing 61d, is supported by spanning both end faces 15a of the distal portion 12b1 of the curved grooved plate portion 12b of the housing 61d. In this embodiment, as described above, the backing member 80 supporting the ultrasonic transmitter / receiver unit 61a is supported by spanning both end faces 15a of the distal portion 12b1 of the housing 61d. In this manner, by positioning the ultrasonic transmitter / receiver unit 61a using both end faces 15a of the distal portion 12b1 of the curved grooved plate portion 12b of the housing 61d, the ultrasonic transmitter / receiver unit 61a can be easily positioned in the catheter circumferential direction B relative to the housing 61d.

[0084] In this way, by performing the holder positioning step S4 and the support step S5, it is possible to easily perform relative positioning of the ultrasound transmitting and receiving unit 61a and the optical transmitting and receiving unit 61b held by the holder 61c in the catheter circumferential direction B. Therefore, for example, by rotating the holder 61c in the catheter circumferential direction B with respect to the housing 61d, it is possible to prevent the positional relationship in the catheter circumferential direction B between the transmission direction of ultrasound from the ultrasound transmitting and receiving unit 61a and the transmission direction of light from the optical transmitting and receiving unit 61b from deviating from the desired state.

[0085] The order in which the holder positioning step S4 and the supporting step S5 are performed is not particularly limited. The holder positioning step S4 may be performed first, followed by the supporting step S5, or the supporting step S5 may be performed first, followed by the holder positioning step S4. Alternatively, the holder positioning step S4 and the supporting step S5 may be performed simultaneously.

[0086] After the holder positioning step S4 and the support step S5 are completed, the ultrasonic transceiver 61a and the optical transceiver 61b are fixed in position relative to the housing 61d using an adhesive or the like. In this case, the adhesive for fixing the holder 61c to the housing 61d may be filled through the space within the recess 15b2 (see FIGS. 5, 7, and 8). Because the protrusion 61c2 fits between both end faces 15b of the proximal portion 12b2, providing the recess 15b2 with an adhesive filling port allows for more reliable supply of adhesive between the holder body 61c1 within the proximal portion 12b2 and the inner surface of the proximal portion 12b2.

[0087] Thereafter, a protection step S6 is performed in which a protection member 61e that covers the distal end 61d2 of the housing 61d is attached to the housing 61d.

[0088] Here, the retracting step S3 is shown in which the ultrasonic transmitter / receiver unit 61a, to which the electric signal line 14a is connected in advance, is retracted using the opening 61d1. However, the manufacturing method is not limited to this. That is, the diagnostic imaging catheter according to the present disclosure may be manufactured by a manufacturing method in which the ultrasonic transmitter / receiver unit 61a is fixed to the housing 61d and then the electric signal line 14a is connected to the ultrasonic transmitter / receiver unit 61a fixed to the housing 61d. Even in such a case, as in the present embodiment, by positioning the ultrasonic transmitter / receiver unit 61a and the holder 61c that holds the optical transmitter / receiver unit 61b via the optical transmission line 14b so that they do not rotate in the catheter circumferential direction B relative to the housing 61d, the ultrasonic transmitter / receiver unit 61a and the optical transmitter / receiver unit 61b can be easily positioned relative to the housing 61d while maintaining a desired positional relationship in the catheter circumferential direction B between the direction of ultrasonic transmission from the ultrasonic transmitter / receiver unit 61a and the direction of light transmission from the optical transmitter / receiver unit 61b.

[0089] The diagnostic imaging catheter according to the present disclosure is not limited to the specific configurations shown in the above-described embodiments, and various modifications, changes, and combinations are possible without departing from the scope of the claims.

[0090] The present disclosure relates to diagnostic imaging catheters.

[0091] 10: Probe 12a: Cylinder portion 12b: Curved grooved plate portion 12b1: Distal portion of curved grooved plate portion 12b2: Proximal portion of curved grooved plate portion 13: Drive shaft 14a: Electric signal line 14b: Optical transmission line 15: End face of curved grooved plate portion 15a: End face of distal portion of curved grooved plate portion 15b: End face of proximal portion of curved grooved plate portion 15b1: Restricting portion 15b2: Recessed portion 15c: Step surface 16: Rotation restricting portion 17: Support portion 18: Guide portion 19: Abutting portion 20: Sheath 20a: Main body portion 20b: Guide wire insertion portion 21a: First hollow portion 21b: Second hollow portion 22: Reinforcing member 22a: Communication path 22a1: Communication hole 23: Contrast marker portion 30: Inner tube 31: Inner tube body 32: Hub 40: Outer tube 41: Outer tube body 42: Distal connector 43: Proximal connector 60: Imaging core 61a: Ultrasound transmitting and receiving unit 61b: Light transmitting and receiving unit 61b1: Optical element 61c: Holding body 61c1: Holding body 61c2: Protrusion 61c3: Holding hole 61c4: Insertion hole 61d: Housing 61d1: Opening 61d2: Distal end of housing 61d3: Storage space 61e: Protective member 61e1: Main body 61e2: Fixing part 62: Ultrasound transducer 62a: Main body 62b: Electrode 63: Groove 70: Peripheral wall 80: Backing member 100: Diagnostic imaging device 110: Diagnostic imaging catheter 120: External device 120a: Drive unit 120b: Control device 120c: Monitor 121, 122: Motor 123: Ball screw A: Catheter longitudinal direction A1: Insertion direction A2: Removal direction B: Catheter circumferential direction C: Catheter radial direction O: Central axis W: Guide wire

Claims

1. An imaging catheter for image diagnosis, comprising a drive shaft and an imaging core connected to the drive shaft, wherein the imaging core comprises an ultrasonic transceiver, an optical transceiver, an optical transmission line connected to the optical transceiver, a holder holding the optical transmission line, and a housing supporting the ultrasonic transceiver, the optical transceiver, and the holder, and an opening is formed in the housing through which ultrasonic waves transmitted and received by the ultrasonic transceiver and light transmitted and received by the optical transceiver can pass, and the ultrasonic transceiver and the holder are each positioned in the circumferential direction of the catheter with respect to the housing by edges on both sides in the circumferential direction of the catheter of the opening of the housing.

2. The opening of the housing is formed in a peripheral wall that partitions an accommodation space capable of accommodating the ultrasonic transceiver, the optical transceiver, and the holder therein, and the holder comprises a holding body accommodated in the accommodation space of the housing and a protruding portion protruding radially outward in the catheter diameter direction, and the edges on both sides of the opening sandwich the protruding portion from both sides in the circumferential direction of the catheter and comprise a rotation restricting portion that restricts rotation of the protruding portion in the circumferential direction of the catheter with respect to the housing. The imaging catheter according to claim 1.

3. The rotation restricting portion comprises a restricting portion capable of restricting rotation in the circumferential direction of the catheter by abutting against the protruding portion of the holder and a recess recessed in the circumferential direction of the catheter from the restricting portion. The imaging catheter according to claim 2.

4. The edges on both sides of the opening are bridged so as to straddle the ultrasonic transceiver and comprise a supporting portion that supports the ultrasonic transceiver. The imaging catheter according to claim 2 or 3.

5. The edges on both sides of the opening comprise a guiding portion in which the distance between each other in the circumferential direction of the catheter gradually decreases from the distal side to the proximal side in the longitudinal direction of the catheter toward the rotation restricting portion. The imaging catheter according to claim 4.

6. The protruding portion comprises a groove formed on a surface radially outward in the catheter diameter direction. The imaging catheter according to claim 2 or 3.

7. The image diagnostic catheter according to any one of claims 1 to 3, comprising an electrical signal line connected to the ultrasonic transmitting and receiving unit, and an insertion hole through which the electrical signal line is inserted is formed in the holding body.

8. The drive shaft is continuous with the proximal side in the longitudinal direction of the catheter with respect to the housing, and the optical transmission line and the electrical signal line extend in the drive shaft. The image diagnostic catheter according to claim 7.

9. The opening of the housing extends to the distal end of the housing. The image diagnostic catheter according to any one of claims 1 to 3.