JP7193299B2 - diagnostic imaging catheter - Google Patents

Description

The present disclosure relates to diagnostic imaging catheters.

2. Description of the Related Art Conventionally, there has been known a diagnostic imaging catheter that acquires a tomographic image inside a body lumen such as a blood vessel using ultrasound or light. A general diagnostic imaging catheter includes an imaging shaft having an imaging unit for acquiring image information at its distal end, an imaging lumen through which the imaging shaft is inserted, and a catheter distal end at a desired location within a biological lumen. and a hub connected to the proximal end of the shaft, the shaft having a guidewire lumen through which the guidewire used to deliver the drug to the location of .

In addition, Patent Document 1 discloses a first guide wire lumen through which a guide wire (hereinafter referred to as "first guide wire") for guiding the delivery of the tip of the catheter in the main canal of the blood vessel can be inserted. , a second guidewire lumen which is arranged closer to the proximal end of the sheath than the first guidewire lumen and through which a guidewire inserted into a side branch of a blood vessel (hereinafter referred to as a "second guidewire") can be passed. A diagnostic imaging catheter is described that includes a sheath formed with a .

The diagnostic imaging catheter described in Patent Document 1 can be used, for example, for a procedure in which a guide wire is inserted into the side branch after a stent is placed in the main canal of the blood vessel so as to overlap the side branch of the blood vessel.

When the diagnostic imaging catheter described in Patent Document 1 is used for the above procedure, the tip of the catheter is placed in the main canal of the blood vessel by means of the first guidewire inserted into the first guidewire lumen. A second guidewire can be delivered through the second guidewire lumen into the side branch of the blood vessel. Therefore, by using the catheter for image diagnosis, the operator inserts the second guide wire into the side branch after confirming the state of the side branch of the blood vessel after placing the stent in the main canal of the blood vessel. can do.

Japanese Patent Application Laid-Open No. 2004-203249

In the diagnostic imaging catheter described in Patent Document 1, the first guide wire lumen and the second guide wire lumen are arranged at positions facing each other on the axis-orthogonal cross section of the shaft so as to sandwich the imaging lumen therebetween. there is In other words, in the diagnostic imaging catheter described above, since three lumens are arranged side by side on the cross section perpendicular to the axis, the external dimensions of the shaft (dimensions in the vertical direction and the horizontal direction on the cross section perpendicular to the axis) are large. Therefore, the diagnostic imaging catheter described above has a problem in terms of deliverability within a body lumen such as a blood vessel.

Accordingly, an object of the present disclosure is to provide a diagnostic imaging catheter that allows a guide wire to be easily inserted into a side branch or the like of a biological lumen and has improved deliverability within the biological lumen.

A diagnostic imaging catheter according to one aspect of the present invention includes an axially extending sheath that can be inserted into a living body, and the sheath is formed with a first guidewire lumen through which a first guidewire can be passed. and an inserting portion formed with an imaging lumen, which is disposed closer to the base end side in the axial direction than the distal end-side insertion portion and into which an imaging shaft having an imaging unit provided at the distal end portion is inserted. a proximal-side insertion portion disposed closer to the proximal side in the axial direction than the distal-side insertion portion and formed with a second guide wire lumen through which a second guide wire can be inserted; The insertion section has an observation window that enables acquisition of a diagnostic image by the imaging unit, and the observation window is formed closer to the distal side than the proximal-side insertion section. A central axis of the wire lumen is arranged at a position overlapping with the imaging lumen on an axis-perpendicular cross section of the sheath, the distal end-side insertion portion and the insertion portion are spaced apart in the axial direction, and the The sheath has a reinforcing member that connects the distal end-side insertion portion and the insertion portion, and the reinforcing member is arranged at a position that does not overlap with the distal end-side insertion portion on an axis-perpendicular cross-section of the sheath .

According to the present disclosure, by passing a first guidewire through a first guidewire lumen and a second guidewire through a second guidewire lumen, a main body lumen (e.g., a blood vessel) A second guidewire can be inserted into a side branch of the body lumen (eg, a side branch of a blood vessel) while the catheter remains inserted into the main canal of the body. Further, according to the present disclosure, the central axis of the first guidewire lumen is arranged at a position overlapping the imaging lumen on the axis-perpendicular cross-section of the sheath. Therefore, at least a portion of the first guidewire lumen and at least a portion of the imaging lumen are arranged so as to overlap on the cross-section orthogonal to the axis of the sheath. Thereby, the external dimensions of the sheath are smaller than when the first guidewire lumen and the imaging lumen are arranged without overlapping on the orthogonal cross-section of the sheath. Therefore, the diagnostic imaging catheter according to the present disclosure has improved deliverability within a biological lumen.

1 is a diagram schematically showing a diagnostic imaging catheter according to an embodiment; FIG. FIG. 2 is an axial cross-sectional view of the vicinity of the distal end portion of the diagnostic imaging catheter according to the embodiment; 3 is an orthogonal cross-sectional view of the sheath taken along line arrows 3-3 shown in FIG. 2; FIG. Figure 4 is an orthogonal cross-sectional view of the sheath taken along line arrows 4-4 shown in Figure 2; Figure 5 is an orthogonal cross-sectional view of the sheath taken along arrows 5-5 shown in Figure 2; Figure 6 is an orthogonal cross-sectional view of the sheath taken along arrows 6-6 shown in Figure 2; 1 is a cross-sectional view schematically showing a usage example of a diagnostic imaging catheter according to an embodiment; FIG. It is a figure which shows the modification of a front end side insertion part, and is a cross-sectional view of the sheath|sheath corresponding to FIG. FIG. 5 is a view showing a modified example of the reinforcing member, and is a cross-sectional view of the sheath corresponding to FIG. 4, taken perpendicular to the axis; FIG. 6 is a view showing a modification of the insertion portion, and is a cross-sectional view of the sheath corresponding to FIG. 5, taken perpendicular to the axis. FIG. 7 is a view showing a modified example of the proximal-side insertion portion, and is a cross-sectional view of the sheath corresponding to FIG. 6 , perpendicular to the axis.

Hereinafter, embodiments according to one aspect of the present invention will be described with reference to the attached drawings. The following description does not limit the technical scope or the meaning of terms described in the claims. Also, the dimensional ratios in the drawings are exaggerated for convenience of explanation, and may differ from the actual ratios.

1 to 6 are diagrams for explaining each part of the diagnostic imaging catheter 10 according to the embodiment, and FIG. 7 is a cross-sectional view schematically showing a usage example of the diagnostic imaging catheter 10. As shown in FIG.

The diagnostic imaging catheter 10 is configured as an ultrasound catheter (IVUS catheter) for acquiring diagnostic images by ultrasound. The diagnostic imaging catheter 10 is connected to an external driving device (MDU, not shown) for driving a signal transmitting/receiving unit (imaging core) 311, which will be described later, when acquiring a diagnostic image.

In the following description, the side of the sheath 100 that is inserted into a biological lumen is referred to as the "distal side," the side of the sheath 100 on which the hub 200 is arranged is referred to as the "proximal side," and the direction in which the sheath 100 extends is referred to as the "axial side." "Direction". In the description of the specification, the term “distal end” means the distal end (most distal end) of the member and a portion that includes a certain range extending from the distal end in the axial direction. base end) and a portion including a certain range extending from the base end in the axial direction.

The axial direction of the sheath 100 is indicated by arrow X in each figure. An arrow Y indicates a depth direction perpendicular to the axial direction of the sheath 100, and an arrow Z indicates a height direction perpendicular to each of the axial direction and the depth direction. The cross-section perpendicular to the axis of the sheath 100 described in the specification is a cross-section perpendicular to the axial direction of the sheath 100 and means the YZ plane (see FIGS. 3 to 6). Moreover, the circumferential direction of the sheath 100 is the direction along the outer peripheral surface of each part of the sheath 100, and is indicated by an arrow R in the drawing.

As shown in FIG. 1, the diagnostic imaging catheter 10 includes a sheath 100 extending in the axial direction that can be inserted into a living body, a hub 200 connected to the sheath 100, and an imaging unit 310 at the distal end. and an imaging shaft 300 inserted into 100 .

As shown in FIG. 7, the diagnostic imaging catheter 10 is guided by a first guide wire W1 inserted through a first guide wire lumen 113 of a distal insertion portion 110 disposed near the distal end portion 101 of the sheath 100. The distal end portion 101 of the sheath 100 is configured as a rapid exchange type catheter capable of delivering to a desired position of the main tube M of the blood vessel (corresponding to the "biological lumen") B. In addition, the diagnostic imaging catheter 10 allows the second guide wire W2 inserted into the side branch b of the blood vessel B to extend along the axial direction of the sheath 100 via the insertion port 220 of the hub 200. It has a structure that can be inserted into the lumen 133 .

<sheath>
As shown in FIGS. 1 and 2, the sheath 100 includes a distal end-side insertion portion 110 formed with a first guide wire lumen 113 through which the first guide wire W1 can be passed, and an axially extending portion 110 that is closer to the distal end-side insertion portion 110. The insertion portion 120 is arranged on the proximal side in the direction and formed with an imaging lumen 123 into which the imaging shaft 300 is inserted; and a proximal-side insertion portion 130 formed with a second guide wire lumen 133 through which the wire W2 can be inserted.

<Tip side insertion part>
As shown in FIG. 2, the distal insertion portion 110 has a distal opening 111 that communicates with the distal end of the first guidewire lumen 113 and a proximal opening 112 that communicates with the proximal end of the first guidewire lumen 113. and have

The distal end portion of the distal end-side insertion portion 110 is formed in a tapered shape in which the outer diameter gradually decreases toward the distal end side. The proximal end portion of the distal end-side insertion portion 110 has a cross-sectional shape that is obliquely inclined toward the outer surface of the reinforcing member 140 arranged on the proximal end side of the distal end-side insertion portion 110 . The proximal end opening 112 has a cross-sectional shape that is inclined in the same direction as the direction of inclination of the proximal end of the distal insertion portion 110 .

As shown in FIG. 3, the outer peripheral surface and the inner peripheral surface near the center in the axial direction of the distal end-side insertion portion 110 have a substantially circular cross-section perpendicular to the axis. Reference symbol C1 in the drawing indicates the position of the central axis of the first guide wire lumen 113 .

The distal end-side insertion portion 110 can be composed of, for example, a single-layer tube made of a resin material. HDPE (high-density polyethylene), for example, can be used as a material for forming the distal end-side insertion portion 110 . The inner diameter of the distal insertion portion 110 (the diameter of the first guidewire lumen 113) can be set to 0.25 mm to 0.46 mm, for example. The outer diameter of the distal end-side insertion portion 110 near the center in the axial direction can be set to, for example, 0.3 mm to 0.6 mm. There are no particular restrictions on the type of material forming the distal end-side insertion portion 110, the inner diameter and outer diameter of the distal end-side insertion portion 110 on the cross section perpendicular to the axis, the length of the distal end-side insertion portion 110 in the axial direction, and the like.

<Insert part>
As shown in FIG. 2 , the insertion section 120 is formed on the distal side of the proximal insertion section 130 , and includes an observation window section 125 that enables acquisition of a diagnostic image by the imaging unit 310 and an imaging lumen 123 . and an outlet 128 that communicates the distal end with the outside of the sheath 100 .

The observation window section 125 is configured to allow transmission of ultrasonic waves emitted from the signal transmission/reception section 311 of the imaging unit 310 arranged in the imaging lumen 123 . Transmissiveness of ultrasonic waves means that the refractive index is low (high transmittance) to the extent that the image quality of the diagnostic image acquired using the diagnostic imaging catheter 10 is not significantly impaired.

The discharge port 128 is provided to discharge the priming liquid (ultrasonic transmission liquid) filled in the imaging lumen 123 . When acquiring a diagnostic image using the diagnostic imaging catheter 10, the imaging lumen 123 is filled with a priming liquid. When the imaging lumen 123 is sufficiently filled with the priming liquid, the discharge port 128 discharges excess priming liquid to the outside of the imaging lumen 123 . For example, physiological saline can be used as the priming liquid.

When the sheath 100 is inserted into the blood vessel while the imaging lumen 123 is filled with the priming liquid, the priming liquid intervenes between the signal transmitter/receiver 311 and the inner wall of the blood vessel. By emitting ultrasonic waves from the signal transmitting/receiving unit 311 in this state, the ultrasonic waves can be well transmitted to the inner wall of the blood vessel via the priming liquid, and can be reflected back from the inner wall of the blood vessel.

Imaging lumen 123 extends to proximal end 103 of sheath 100 (see FIG. 1). The imaging lumen 123 communicates with an internal space (not shown) of the hub 200 . The imaging shaft 300 inserted into the imaging lumen 123 is electrically connected to the driving source of the external driving device when the base end connecting portion 230 of the hub 200 is connected to the external driving device. The imaging lumen 123 also communicates with the port 210 of the hub 200 via the inner lumen of the hub 200 . A supply of priming fluid into the imaging lumen 123 may be provided through the port 210 of the hub 200 .

As shown in FIGS. 2 and 5, the sheath 100 has a guide portion 150 formed on the outer peripheral surface of the insertion portion 120. As shown in FIGS.

As shown in FIG. 2, the guide portion 150 is arranged closer to the distal side than the proximal-side insertion portion 130 . Therefore, the guide portion 150 partially overlaps the observation window portion 125 in the axial direction.

The guide portion 150 is arranged at a location (location on the upper side in FIG. 5) that is close in the circumferential direction to the location where the tip opening 131 of the base-end insertion portion 130 is located.

As shown in FIG. 5, the guide portion 150 is composed of a pair of first convex portion 151 and second convex portion 152 that protrude from the outer surface of the sheath 100 (the outer surface of the insertion portion 120).

The first convex portion 151 has a base portion 151 a formed near the outer surface of the sheath 100 and a top portion 151 b positioned away from the outer surface of the sheath 100 . The width (dimension in the left-right direction in FIG. 5) of the first projection 151 gradually decreases from the base 151a to the top 151b. Further, the first convex portion 151 is inclined from the base portion 151a side to the top portion 151b side in a direction away from the central axis C1 of the first guide wire lumen.

Similarly to the first protrusion 151 , the second protrusion 152 includes a base 152 a formed near the outer surface of the sheath 100 and a top 152 b positioned away from the outer surface of the sheath 100 . have. The second convex portion 152 has a shape symmetrical to the first convex portion 151 in the vertical cross-sectional view shown in FIG.

The guide portion 150 is provided to guide the second guide wire W2 inserted through the proximal-side insertion portion 130 to a predetermined range in the circumferential direction of the sheath 100 (range indicated by arrow A in FIG. 5). . As shown in FIG. 7, the second guide wire W2 protruding from the distal end opening 131 of the proximal insertion portion 130 is guided to the side branch b branching from the main tube M of the blood vessel B. As shown in FIG. At this time, if the operator can hold the second guide wire W2 on the side where the side branch b is located in the circumferential direction of the sheath 100, the operator can move the second guide wire W2 toward the side branch b. become easier. When the operator guides the second guide wire W2 to the side branch b, as shown in FIG. 2 guide wire W2 is placed. By arranging the second guide wire W2 in the gap, the operator suppresses the deviation of the second guide wire W2 from the predetermined range (the range indicated by the arrow A) in the circumferential direction of the sheath 100. be able to. Therefore, the operator can easily guide the second guide wire W2 protruding from the distal opening 131 of the proximal-side insertion portion 130 toward the side branch b.

The specific shape of the guide part 150 is not particularly limited as long as it can guide the second guide wire W2 to a predetermined range in the circumferential direction of the sheath 100 . For example, the guide portion 150 may be a single convex portion, such as a tubular member formed with a concave groove formed on the outer surface of the sheath 100 or a passage obliquely extending toward the side branch b. may Further, in the present embodiment, the guide portion 150 is formed integrally with the insertion portion 120 of the sheath 100, but may be formed by connecting a separate member to the sheath 100, for example.

The insertion portion 120 can be configured by, for example, a single-layer tube made of a resin material. HDPE, for example, can be used as a material for forming the insertion portion 120 . The inner diameter of the insertion portion 120 (the diameter of the imaging lumen 123) can be set to 0.6 mm to 0.7 mm, for example. The outer diameter of the observation window 125 of the insertion section 120 (virtual outer diameter when the guide section 150 is not formed) can be set to, for example, 0.8 mm to 0.9 mm. There are no particular restrictions on the type of material forming the insertion portion 120, the inner and outer diameters of the insertion portion 120 on the cross section orthogonal to the axis, the length of the observation window portion 125 in the axial direction, and the like.

<Base end insertion part>
The proximal-side insertion portion 130 has a distal opening 131 that communicates with the distal end of the second guidewire lumen 133, as shown in FIG.

A distal end portion 131 a of the proximal-side insertion portion 130 has a tapered shape in which the outer shape gradually tapers toward the distal end side of the sheath 100 . Therefore, the distal end opening 131 has a cross-sectional shape that is inclined in the same direction as the tilting direction of the distal end portion 131 a of the proximal end insertion portion 130 .

A second guidewire lumen 133 extends to the proximal end 103 of the sheath 100 (see FIG. 1). The second guidewire lumen 133 communicates with the internal space (not shown) of the hub 200 . Also, the second guide wire lumen 133 communicates with an insertion port 220 provided in the hub 200 .

As described above, the imaging lumen 123 of the insertion section 120 extends to the proximal end of the sheath 100 . Therefore, the imaging lumen 123 extends from the vicinity of the distal end portion 131a of the proximal-side insertion portion 130 (near the proximal end of the observation window portion 125) to the proximal end of the sheath 100 along the second guide wire lumen 133 and the axial direction. Up to the part 103 is arranged side by side.

In the diagnostic imaging catheter 10, as shown in FIG. 6, the second guide wire lumen 133 and the imaging lumen 123 are arranged at positions facing each other on the cross section perpendicular to the axis. The position facing each other is based on the central position O in the height direction (vertical direction in FIG. 6) on the cross section perpendicular to the axis of the portion where the imaging lumen 123 and the second guide wire lumen 133 are arranged side by side. This means that each of the imaging lumen 123 and the second guide wire lumen 133 is arranged at a position offset from the center position O toward one end side e1 and the other end side e2 in the height direction.

The first guide wire lumen 113 is arranged at a position facing the second guide wire lumen 133 on the axis-perpendicular cross section, similarly to the imaging lumen 123 . In FIG. 6, the position of the first guide wire lumen 113 on the cross-section perpendicular to the axis is indicated by a virtual line (chain double-dashed line). In addition, in this embodiment, the central axis C1 of the first guide wire lumen 113 is arranged at a position overlapping the imaging lumen 123 on the axis-perpendicular cross-section.

As shown in FIG. 6, in the sheath 100, the imaging lumen 123 and the second guide wire lumen 133 are arranged side by side so that the two lumens 123 and 133 are located at different height directions on the cross section perpendicular to the axis. placed. A plurality of lumens in the sheath 100 are arranged at different positions in the height direction on the cross section perpendicular to the axis only in the portion where the imaging lumen 123 and the second guide wire lumen 133 are arranged side by side. Therefore, in the portion where the imaging lumen 123 and the second guide wire lumen 133 are arranged side by side, the outer dimension of the sheath 100 (the length in the vertical direction in FIG. 6) becomes the maximum value t1.

On the other hand, in the first guidewire lumen 113, as described above, the central axis C1 of the first guidewire lumen 113 overlaps the imaging lumen 123 on the cross section perpendicular to the axis. Therefore, at least part of the first guide wire lumen 113 and at least part of the imaging lumen 123 are arranged so as to overlap on the cross-section perpendicular to the axis. In the sheath 100, the position of the first guide wire lumen 113 and the position of the imaging lumen 123 do not largely deviate on the axial cross section. Therefore, in the diagnostic imaging catheter 10, when the first guide wire lumen 113 and the second guide wire lumen 133 are arranged with the imaging lumen 123 interposed therebetween (three lumens are arranged side by side on the cross section perpendicular to the axis). The maximum value t1 of the external dimensions of the sheath 100 is small compared to the case where the sheath 100 is used.

The positional relationship between the first guidewire lumen 113 and the imaging lumen 123 is not particularly limited as long as the central axis C1 of the first guidewire lumen 113 overlaps the imaging lumen 123 on the cross section perpendicular to the axis. However, from the viewpoint of reducing the outer dimensions of the sheath 100, it is preferable to arrange the central axis C1 of the first guide wire lumen 113 as close as possible to the central axis (not shown) of the imaging lumen 123. For example, the first guide wire lumen 113 and the imaging lumen 123 do not have to be arranged at positions facing the second guide wire lumen 133 on the cross-section orthogonal to the axis of the sheath 100 .

The base-end-side insertion portion 130 can be configured by, for example, a single-layer tube made of a resin material. In this embodiment, the base-end-side insertion portion 130 is integrally connected to the insertion portion 120 . Specifically, the resin tube forming the base-end insertion portion 130 and the resin tube forming the insertion portion 120 are integrally connected by fusion. HDPE, for example, can be used as a material for forming the base-end-side insertion portion 130 . The inner diameter of the proximal-side insertion portion 130 (the diameter of the second guidewire lumen 133) can be set to, for example, 0.25 mm to 0.46 mm. In addition, the maximum value t1 of the outer dimension of the portion of the sheath 100 where the imaging lumen 123 and the second guide wire lumen 133 are arranged can be set to 0.7 mm to 1.2 mm, for example. There are no particular restrictions on the type of material forming the proximal end insertion portion 130, the inner diameter of the proximal end insertion portion 130 on the cross section orthogonal to the axis, the above outer dimensions, and the like.

<Reinforcing member>
As shown in FIG. 2, the distal insertion portion 110 and the insertion portion 120 are spaced apart in the axial direction. The sheath 100 has a reinforcing member 140 that connects the distal insertion portion 110 and the insertion portion 120 .

The reinforcing member 140 has a distal end 140a, a proximal end 140b, and an intermediate portion 140c extending between the distal end 140a and the proximal end 140b.

A distal end portion 140 a of the reinforcing member 140 is connected to a proximal end portion of the distal end-side insertion portion 110 . A proximal end portion 140 b of the reinforcing member 140 is connected to the distal end portion of the insertion portion 120 . The connection between the reinforcing member 140 and the distal insertion portion 110 and the connection between the reinforcing member 140 and the insertion portion 120 can be performed by fusion or adhesion, for example.

A distal end portion 140 a of the reinforcing member 140 has a tapered shape in which the outer shape gradually tapers toward the distal end side of the sheath 100 . A proximal end portion 140b of the reinforcing member 140 has a tapered shape in which the outer shape gradually tapers toward the proximal end side of the sheath 100. As shown in FIG. The intermediate portion 140c of the reinforcing member 140 extends substantially linearly between the distal end portion 140a and the proximal end portion 140b.

In the sheath 100, the distal end-side insertion portion 110 and the insertion portion 120 are spaced apart in the axial direction, so that the first guide wire W1 can be arranged between the distal end-side insertion portion 110 and the insertion portion 120. space a. Therefore, it is possible to prevent the first guide wire W<b>1 led out from the proximal end opening 112 of the distal insertion section 110 toward the proximal side from interfering with the insertion section 120 . In addition, since the distal end-side insertion portion 110 and the insertion portion 120 of the sheath 100 are connected to each other via the reinforcing member 140, breakage or the like between the distal end-side insertion portion 110 and the insertion portion 120 can be prevented. can.

A distal end portion 140a of the reinforcing member 140 has a tapered shape in which the outer shape becomes smaller toward the distal end side. Therefore, when the operator moves the sheath 100 within the body lumen, the distal end portion 140a of the reinforcing member 140 can be prevented from coming into contact with the inner wall of the blood vessel or the like, thereby reducing delivery performance. Also, the base end portion 140b of the reinforcing member 140 has a tapered shape in which the outer shape becomes smaller toward the base end side. Therefore, when delivering the second guide wire W2 to the side branch b, the operator moves the second guide wire W2 along the outer surface of the proximal end portion 140b of the reinforcing member 140, thereby achieving the second guide wire W2. The guide wire W2 can be easily guided to the side of the side branch b. Furthermore, as shown in FIG. 2, the proximal end portion 140b of the reinforcing member 140 is connected to the distal end portion of the insertion section 120 whose outer shape decreases toward the distal end side in the axial direction. Therefore, at the portion where the proximal end portion 140b of the reinforcing member 140 and the distal end portion of the insertion portion 120 are connected, the increase and decrease in the constituent material (resin material) of both changes gently along the axial direction. Therefore, since the physical step at the portion where the proximal end portion 140b of the reinforcing member 140 and the distal end portion of the insertion portion 120 are connected changes gently along the axial direction, the proximal end portion 140b of the reinforcing member 140 and the insertion portion 120 It is possible to preferably prevent breakage or the like from occurring at the portion where the tip portion of the is connected.

As shown in FIG. 4, the intermediate portion 140c of the reinforcing member 140 includes a convex portion 145b that protrudes in a direction away from the central axis C1 of the first guidewire lumen 113 and a central axis C1 of the first guidewire lumen 113. It has a cross-sectional shape with a concave portion 145a formed on the side.

The reinforcement member 140 does not have a lumen or a hollow space inside. Therefore, the reinforcement member 140 can effectively increase the rigidity of the sheath 100 between the distal insertion portion 110 and the insertion portion 120 .

The reinforcing member 140 can be composed of, for example, a member having a single-layer structure made of a resin material. HDPE, for example, can be used as a material for forming the reinforcing member 140 . There are no particular restrictions on the type of material forming the reinforcing member 140, the shape of the cross section perpendicular to the axis of the reinforcing member 140, the length of the reinforcing member 140 in the axial direction, and the like.

<Hub>
As shown in FIG. 1, the hub 200 includes a port 210 connectable with a syringe for supplying priming fluid into the imaging lumen 123 of the sheath 100 and a second guidewire lumen 133 of the sheath 100 into the second guidewire lumen 133 . and a proximal connection 230 to allow connection of the hub 200 to an external drive.

Hub 200 can be made of, for example, a hard resin material or the like. The specific configuration of the hub 200 is not particularly limited, and may be changed as appropriate according to the specifications of the diagnostic imaging catheter 10 and the like.

<Imaging shaft>
The imaging shaft 300 can be composed of, for example, multiple layers of coils with different winding directions around the axis. Examples of the material of the coil include stainless steel and Ni--Ti (nickel-titanium) alloy.

The imaging unit 310 has a signal transmission/reception section 311 that transmits and receives ultrasonic waves, and a housing 312 in which the signal transmission/reception section 311 is arranged. The signal transmitting/receiving unit 311 is composed of an ultrasonic transducer that generates ultrasonic waves by producing a piezoelectric effect when a voltage is applied. A coil for stabilizing the rotation of the imaging unit 310 may be connected to the tip of the housing 312 .

A signal line (not shown) is arranged inside the imaging shaft 300 to enable electrical signal communication between the external driving device and the signal transmitting/receiving section 311 . The signal line can be composed of, for example, a twisted pair cable or a coaxial cable.

When the operator uses the diagnostic imaging catheter 10, the operator connects the proximal connection portion 230 of the hub 200 to an external driving device. By connecting the base end connection portion 230 of the hub 200 to the external driving device, the operator can supply driving force to the imaging shaft 300 and the imaging unit 310 from the external driving device. The imaging shaft 300 and the imaging unit 310 can be rotated (radially scanned) by driving force supplied from an external driving device, and can image the blood vessel B in 360-degree directions.

Next, a usage example of the diagnostic imaging catheter 10 will be described with reference to FIG. The application of the diagnostic imaging catheter 10 is not limited to the procedures described below. In addition, for procedures and the like that are not particularly described, known methods may be employed as appropriate.

FIG. 7 shows a state in which a stent S is indwelled in the main pipe M of the blood vessel B in order to dilate a stenosed portion (not shown) formed around the entrance of the side branch b of the blood vessel B. As shown in FIG. When confirming the treatment state of the stenosis by the stent S, the operator inserts the diagnostic imaging catheter 10 into the lumen of the stent S and observes the inner wall of the blood vessel from the inside of the stent S. As a result of observing the vicinity of the entrance of the side branch b, the operator confirms that when the stent S is placed in the main tube M, the plaque or the like contained in the stenosis moves and the side branch b is blocked. A portion of the stent S is spread and placed up to the side branch b, or the side branch b is treated with a balloon catheter or the like. The operator inserts the second guidewire W2 through the strut gap g of the stent S and into the side branch b prior to treatment. At this time, the operator can deliver the second guidewire W2 through the second guidewire lumen 133 to the side branch b. Further, the operator operates the second guide wire W2 while confirming the position and the direction of the distal end portion of the second guide wire W2 based on the diagnostic image acquired by the imaging unit 310, thereby adjusting the struts of the stent S. A second guide wire W2 can be protruded toward the side branch b from a desired gap g between them. After inserting the second guide wire W2 into the side branch b, the operator withdraws the diagnostic imaging catheter 10 from the body while maintaining the state where the second guide wire W2 is inserted into the side branch b. Thereafter, the operator can deliver a therapeutic device such as a balloon catheter along the second guidewire W2 to the side branch b, if desired. As described above, after acquiring an image with the diagnostic imaging catheter 10, the operator inserts the second guide wire W2 into the side branch b without removing the diagnostic imaging catheter 10 from the main tube M of the blood vessel B. can do. Therefore, the operator can reduce the work load on the procedure, and can smoothly proceed with the procedure.

The product types of the first guide wire W1 and the second guide wire W2 used in the procedure using the diagnostic imaging catheter 10 may be the same or different.

The effects of the diagnostic imaging catheter 10 according to this embodiment will be described.

The diagnostic imaging catheter 10 according to this embodiment includes an axially extending sheath 100 that can be inserted into a living body. The sheath 100 includes a distal end-side insertion portion 110 formed with a first guide wire lumen 113 through which the first guide wire W1 can be inserted, and a distal end-side insertion portion 110 disposed on the proximal side in the axial direction of the distal end-side insertion portion 110. An insertion portion 120 formed with an imaging lumen 123 into which an imaging shaft 300 having an imaging unit 310 is inserted; and a base-end-side insertion portion 130 formed with a second guide wire lumen 133 through which the wire W2 can be inserted. 125 , and the observation window 125 is formed on the distal side of the proximal insertion portion 130 . The central axis C<b>1 of the first guide wire lumen 113 is arranged at a position overlapping the imaging lumen 123 on the axis-perpendicular cross section of the sheath 100 .

According to the diagnostic imaging catheter 10 configured as described above, the first guide wire W1 is passed through the first guide wire lumen 113, and the second guide wire W2 is passed through the second guide wire lumen 133. By doing so, the second guide wire W2 can be inserted into the side branch b of the blood vessel B while maintaining the state where the sheath 100 is inserted into the main tube M of the blood vessel B. Further, according to the diagnostic imaging catheter 10 , the central axis C<b>1 of the first guidewire lumen 113 is arranged at a position overlapping the imaging lumen 123 on the cross-section orthogonal to the axis of the sheath 100 . Therefore, at least a portion of the first guide wire lumen 113 and at least a portion of the imaging lumen 123 are arranged so as to overlap on the cross-section orthogonal to the axis of the sheath 100 . As a result, the outer dimensions of the sheath 100 are smaller than when the first guide wire lumen 113 and the imaging lumen 123 are arranged without overlapping on the cross section of the sheath 100 perpendicular to the axis. Therefore, the diagnostic imaging catheter 10 has improved deliverability within the blood vessel B. As shown in FIG.

In addition, the distal insertion portion 110 and the insertion portion 120 are spaced apart in the axial direction of the sheath 100 . The sheath 100 has a reinforcing member 140 that connects the distal insertion portion 110 and the insertion portion 120 . Between the distal end-side insertion portion 110 and the insertion portion 120, a space a is formed in which the first guide wire W1 can be placed. It is possible to prevent the first guide wire W<b>1 led out from 112 toward the proximal side from interfering with the insertion section 120 . In addition, the sheath 100 preferably prevents breakage or the like between the distal end-side insertion portion 110 and the insertion portion 120 by connecting the distal end-side insertion portion 110 and the insertion portion 120 via the reinforcing member 140. be able to.

Further, the distal end portion 140a of the reinforcing member 140 has a tapered shape in which the outer shape gradually tapers toward the distal end side of the sheath 100. As shown in FIG. Therefore, when the sheath 100 is moved within the blood vessel B, it is possible to prevent the distal end portion 140a of the reinforcing member 140 from coming into contact with the inner wall of the blood vessel or the like, thereby reducing the deliverability.

A proximal end portion 140b of the reinforcing member 140 has a tapered shape in which the outer shape gradually tapers toward the proximal end side of the sheath 100. As shown in FIG. Therefore, when delivering the second guide wire W2 to the side branch b, by moving the second guide wire W2 along the outer surface of the proximal end portion 140b of the reinforcing member 140, the second guide wire W2 is delivered. It can be easily guided to the side branch b.

In addition, the sheath 100 is disposed on the distal side of the proximal-side insertion portion 130, and holds the second guide wire W2 inserted through the proximal-side insertion portion 130 within a predetermined range in the circumferential direction of the sheath 100. It has a guide portion 150 for When inserting the second guide wire W2 into the side branch b, the operator uses the guide portion 150 to prevent the second guide wire W2 protruding from the proximal-side insertion portion 130 from being displaced in the circumferential direction of the sheath 100. can be suppressed. Therefore, the operator can easily guide the second guide wire W2 from the proximal-side insertion portion 130 toward the side branch b.

Also, the guide part 150 has at least one protrusion 151 , 152 protruding from the outer surface of the sheath 100 . Therefore, since the second guide wire W2 protruding from the proximal-side insertion portion 130 can be held by the protrusions 151 and 152, the second guide wire W2 is prevented from slipping along the circumferential direction of the sheath 100. can be suppressed more reliably.

Further, the guide portion 150 overlaps the observation window portion 125 at least partially in the axial direction. Therefore, at least part of the second guide wire W2 is guided toward the side branch b through a position overlapping the observation window portion 125 in the axial direction of the sheath 100 . Therefore, the operator can easily guide the second guide wire W2 toward the side branch with the guide part 150 while more reliably confirming the position of the second guide wire W2 under the acquired diagnostic image. .

Further, the distal end portion 131 a of the proximal-side insertion portion 130 has a tapered shape in which the outer shape gradually tapers toward the distal end side of the sheath 100 . Therefore, the second guide wire W2 protruding from the proximal-side insertion portion 130 can be easily guided away from the outer surface of the sheath 100, and the second guide wire W2 can be guided into the side branch b. It can be inserted smoothly.

<Modification>
Next, modified examples of the structure of each part of the sheath 100 will be described. In the description of each modified example, detailed descriptions of the configurations and the like that have already been described in the above-described embodiments are omitted. In addition, the contents that are not particularly described in the description of the modification can be the same as those of the embodiment.

FIG. 8 shows an axis-perpendicular cross-sectional view of the distal end-side insertion portion 110 according to the modification. The distal end-side insertion portion 110 may have, for example, a multi-layer structure consisting of a first layer (inner layer) 110a and a second layer (outer layer) 110b. The first layer 110a can be made of HDPE, for example, and the second layer 110b can be made of LDPE (low density polyethylene), for example. The thickness of the first layer 110a and the thickness of the second layer 110b are not particularly limited.

FIG. 9 shows an axis-perpendicular cross-sectional view of a reinforcing member 140 according to a modification. Reinforcing member 140 may be formed, for example, to have a circular cross-sectional shape as shown. As another modified example of the reinforcing member 140, for example, a structure in which the interior of a hollow member is filled with a filler (resin adhesive or the like) may be adopted. Even when adopting such a configuration, the cross-sectional shape of reinforcing member 140 is not particularly limited.

FIG. 10 shows an axis-perpendicular cross-sectional view of an insertion portion 120 according to a modification. The insertion section 120 (the portion of the insertion section 120 that is not arranged in parallel with the proximal end insertion section 130) has, for example, a multi-layer structure composed of a first layer (inner layer) 120a and a second layer (outer layer) 120b. may be The first layer 120a can be made of HDPE, for example, and the second layer 120b can be made of LDPE, for example. The thickness of the first layer 110a and the thickness of the second layer 110b are not particularly limited. Although the modified example shown in FIG. 10 shows a form in which the guide portion 150 is not formed, the insertion portion 120 may be configured with a multi-layer structure when the guide portion 150 is formed.

FIG. 11 shows an axis-perpendicular cross-sectional view of the base-end-side insertion portion 130 according to the modification. The base-end-side insertion portion 130 may have, for example, a multilayer structure consisting of a first layer (inner layer) 130a and a second layer (outer layer) 130b. The first layer 130a can be made of HDPE, for example, and the second layer 130b can be made of LDPE, for example. The thickness of the first layer 130a is not particularly limited. In addition, when the proximal-side inserting portion 130 has a multi-layered structure as described above, the inserting portion 120 (a portion of the inserting portion 120 that is arranged side by side with the proximal-side inserting portion 130) has a shape as shown in FIG. , may have a multilayer structure consisting of a first layer (inner layer) 120c and a second layer (outer layer) 120d. The first layer 120c can be made of HDPE, for example, and the second layer 120d can be made of LDPE, for example. The thickness of the first layer 120c is not particularly limited.

The structure of each part of the sheath 100 described in the above embodiment and the structure of each part of the sheath 100 shown in each modification may be combined arbitrarily as long as the effects of the invention are not impaired.

Although the diagnostic imaging catheter according to the present disclosure has been described above through the embodiments and modifications, the diagnostic imaging catheter according to the present disclosure is not limited to each of the configurations described above, and can be used as appropriate based on the description of the claims. You can change it.

For example, in the embodiments, an example of application to an ultrasound catheter for acquiring a diagnostic image of a biological lumen according to the present disclosure has been described. Applicable to diagnostic imaging catheters that acquire images using light such as Optical Coherence Tomography), and dual-type diagnostic imaging catheters that can use both ultrasonic diagnostic methods and optical coherence tomography diagnostic methods. You may When the diagnostic imaging catheter according to the present disclosure is applied to the diagnostic imaging catheter that obtains an image using light, the observation window provided in the sheath is configured to have optical transparency.

Further, the diagnostic imaging catheter may be configured to perform a pullback operation to move the imaging shaft to the proximal end side of the sheath when acquiring a diagnostic image.

Also, the biological lumen to be treated using the diagnostic imaging catheter may be other than blood vessels, such as the bile duct, trachea, esophagus, urethra, ear nasal cavity, and the like.

10 diagnostic imaging catheter,
100 sheath,
101 sheath tip,
103 proximal end of the sheath,
110 tip side insertion part,
113 first guidewire lumen;
120 insert,
123 imaging lumens,
125 observation window,
130 proximal end insertion portion,
131a the distal end of the insertion portion on the proximal side,
133 second guidewire lumen;
140 reinforcing member,
140a the tip of the reinforcing member,
140b proximal end of reinforcing member;
140c intermediate portion of the reinforcing member;
150 guide part,
151 first protrusion (protrusion),
152 second convex portion (convex portion),
200 hub,
300 imaging shaft,
310 imaging unit,
C1 the central axis of the first guidewire lumen;
O the center position in the height direction of the cross section perpendicular to the axis,
W1 first guidewire;
W2 second guidewire;
B blood vessel (biological lumen),
M main vascular,
b side branches of blood vessels,
S stent,
g stent strut gaps;
t1 Maximum outer dimension of the sheath.

Claims (8)

A diagnostic imaging catheter comprising an axially extending sheath insertable in vivo, comprising:
The sheath is
a distal end-side insertion portion formed with a first guidewire lumen through which the first guidewire can be inserted;
an insertion portion formed with an imaging lumen disposed closer to the proximal end side in the axial direction than the distal end-side insertion portion and into which an imaging shaft having an imaging unit provided at a distal end thereof is inserted;
a proximal-side insertion portion disposed closer to the proximal side in the axial direction than the distal-side insertion portion and formed with a second guide wire lumen through which a second guide wire can be inserted;
The insertion section has an observation window that enables acquisition of a diagnostic image by the imaging unit,
The observation window is formed closer to the distal end than the proximal end insertion portion,
A central axis of the first guide wire lumen is arranged at a position overlapping with the imaging lumen on an axis-perpendicular cross-section of the sheath ,
The distal end side insertion portion and the insertion portion are spaced apart in the axial direction,
The sheath has a reinforcing member that connects the distal end side insertion portion and the insertion portion,
The diagnostic imaging catheter , wherein the reinforcing member is arranged at a position not overlapping the distal end-side insertion portion on an axis-orthogonal cross section of the sheath . 2. The diagnostic imaging catheter according to claim 1, wherein said reinforcing member is arranged at a position overlapping said base end side insertion portion on an axis-orthogonal cross section of said sheath. 3. The diagnostic imaging catheter according to claim 1 , wherein the distal end portion of the reinforcing member has a tapered shape whose outer shape gradually tapers toward the distal end side of the sheath. The diagnostic imaging catheter according to any one of claims 1 to 3 , wherein the proximal end portion of said reinforcing member has a tapered shape in which the outer shape gradually tapers toward the proximal end side of said sheath. A diagnostic imaging catheter comprising an axially extending sheath insertable in vivo, comprising:
The sheath is
a distal end-side insertion portion formed with a first guidewire lumen through which the first guidewire can be inserted;
an insertion portion formed with an imaging lumen disposed closer to the proximal end side in the axial direction than the distal end-side insertion portion and into which an imaging shaft having an imaging unit provided at a distal end thereof is inserted;
a proximal-side insertion portion disposed closer to the proximal side in the axial direction than the distal-side insertion portion and formed with a second guide wire lumen through which a second guide wire can be inserted;
The insertion section has an observation window that enables acquisition of a diagnostic image by the imaging unit,
The observation window is formed closer to the distal end than the proximal end insertion portion,
A central axis of the first guide wire lumen is arranged at a position overlapping with the imaging lumen on an axis-perpendicular cross-section of the sheath,
The sheath is disposed on the distal side of the proximal-side insertion portion, and holds the second guidewire inserted through the proximal-side insertion portion within a predetermined range in the circumferential direction of the sheath. A diagnostic imaging catheter having a guide portion. 6. The diagnostic imaging catheter according to claim 5, wherein said guide part has at least one convex part protruding from the outer surface of said sheath. 7. The diagnostic imaging catheter according to claim 5, wherein the guide portion overlaps the observation window portion at least partially in the axial direction. The diagnostic imaging catheter according to any one of claims 1 to 7, wherein the distal end portion of the proximal-side insertion portion has a tapered shape in which the outer shape gradually tapers toward the distal end side of the sheath.

Images