JP2021053445A - Medical device - Google Patents

Abstract

To enhance insertion property into a narrow section while retaining push-in property to the narrow section with respect to a medical device for acquiring diagnostic images of a living body lumen.SOLUTION: An imaging diagnosis catheter includes: a drive shaft 110 disposed with an imaging part 115 capable of acquiring image information; a sheath part 120 having an imaging lumen 125 allowing the drive shaft to be inserted thereinto; a guide wire insertion part 130 having a guide wire lumen 135 allowing a guide wire 200 to be inserted thereinto, and arranged on an external surface at a tip of the sheath part; and a tip member 150 arranged so that a base end part 153 is arranged in the imaging lumen and a tip part 151 projects from the imaging lumen. The guide wire insertion part is arranged in an inclined manner toward an imaging lumen side of the sheath part. The tip part of the tip member is inclined toward a guide wire insertion part side, and is exposed from the imaging lumen over a base end side from the most distal end of the sheath part to be in contact with the guide wire insertion part.SELECTED DRAWING: Figure 3

Description

The present invention relates to a medical device for acquiring a diagnostic image of a biological lumen.

As a medical device for acquiring a diagnostic image of a lesion such as a stenosis generated in a living lumen, a device that acquires a tomographic image using ultrasonic waves or light is known. Further, as this kind of medical device, a drive shaft provided with an imaging unit capable of acquiring image information, a flexible sheath portion having an image lumen through which the drive shaft is inserted, and a sheath portion are provided. There is a so-called rapid exchange type having a guide wire insertion portion arranged on the outer surface on the tip end side of the above (see, for example, Patent Document 1 below).

When a surgeon such as a doctor acquires a diagnostic image using the medical device as described above, the tip side of the medical device is arranged on the inner peripheral side (inner surface side) of the stenosis portion. At this time, if the tip of the medical device can be easily arranged in the narrowed portion, the procedure can be smoothly advanced, so that the procedure time can be shortened and the burden on the patient can be reduced. Therefore, a medical device for acquiring a diagnostic image is required to have insertability (passability) into a narrowed portion.

International Publication No. 2013/11 1700

For example, in the medical device described in Patent Document 1, the tip surface of the tip member (reinforcing member) protruding toward the tip end side of the sheath portion is formed in a tapered shape that is obliquely inclined toward the guide wire insertion portion side. .. On the other hand, the guide wire insertion portion juxtaposed with the sheath portion is formed in a shape extending substantially linearly along the axial direction of the sheath portion. Therefore, it cannot be said that the guide wire insertion portion side has sufficiently improved insertability into the narrowed portion as compared with the sheath portion side.

If there is a structural difference between the sheath portion side and the guide wire insertion portion side as described above, it may be difficult to smoothly insert the medical device into the constricted portion. In such a case, the operator inserts the guide wire insertion portion together with the sheath portion into the narrowed portion by, for example, pushing the sheath portion side into the narrowed portion and expanding the narrowed portion. However, when the guide wire is inserted into the guide wire insertion portion, the guide wire insertion portion is oriented so as to maintain the linearity due to the physical characteristics (rigidity, etc.) of the guide wire. Further, since the guide wire insertion portion loses its flexibility due to the influence of the physical properties of the guide wire, it is difficult to be deformed when it is inserted into the narrowed portion. As a result, it may be more difficult to insert the guide wire insertion portion into the narrowed portion.

In view of the above problems, for example, in order to improve the insertability of the guide wire insertion portion into the narrowed portion, a method of forming the guide wire insertion portion into a tapered shape can be considered. Further, as an example thereof, a method of gradually reducing the wall thickness of the guide wire insertion portion from the base end side to the tip end side can be mentioned. However, if the wall thickness of the guide wire insertion portion is formed to be extremely small, the rigidity of the guide wire insertion portion is lowered and the pushability of the guide wire insertion portion is lowered. Further, if the rigidity of the guide wire insertion portion is reduced, the guide wire insertion portion is likely to be turned over or broken when it is inserted into the narrowed portion.

The present invention has been made to solve the above-mentioned problems, and in a medical device for acquiring a diagnostic image of a biological lumen, it is insertable into a stenosis while maintaining pushability into a stenosis. The purpose is to improve.

The medical device that achieves the above object is a medical device for acquiring an image of a living lumen, and a drive shaft provided with an imaging unit capable of acquiring image information can be inserted into the drive shaft. A sheath portion having an image lumen, a guide wire lumen through which a guide wire can be inserted, a guide wire insertion portion arranged on the outer surface on the tip side of the sheath portion, and a base end portion are used in the image lumen. It has a tip member arranged so that the tip portion protrudes from the image lumen, and the guide wire insertion portion is arranged so as to be inclined toward the image lumen side of the sheath portion. The tip of the tip member is inclined toward the guide wire insertion portion side, and is exposed from the image lumen over the proximal end side of the sheath portion to insert the guide wire. It is in contact with the part.

The medical device configured as described above is inclined toward the tip side so that the guide wire insertion portion and the tip member face each other. Therefore, the medical device has improved insertability into the stenosis. Further, the guide wire insertion portion is arranged so as to be inclined toward the tip side by arranging the sheath portion so as to be inclined toward the image lumen side. Therefore, the medical device does not need to make the wall thickness of the guide wire insertion portion excessively small in order to impart the tapered shape. As a result, the medical device can suitably maintain the pushability to the narrowed portion.

It is a figure which shows generally the whole structure of the medical device which concerns on embodiment, (A) is the side view of the medical device before performing the pullback operation, (B) is the figure when the pullback operation is performed. It is a side view of a medical device. It is a perspective view which shows the tip part of a medical device in an enlarged manner. It is sectional drawing which follows the axial direction of the tip part of a medical device. It is sectional drawing which shows the tip part of a medical device in an enlarged manner. It is a figure which shows simply the arrow view seen from the direction of arrow 5A shown in FIG. It is a figure for demonstrating the operation of the medical device which concerns on embodiment.

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

1 (A) and 1 (B) are views showing a simplified overall configuration of a diagnostic imaging catheter (corresponding to a “medical device”) 100 according to the present embodiment, and FIG. 2 is a diagnostic imaging catheter. A perspective view showing an enlarged tip of 100, FIG. 3 is a cross-sectional view of the tip of the diagnostic imaging catheter 100, and FIGS. 4 and 5 are used for explaining the tip of the diagnostic imaging catheter 100, FIG. Is a diagram for explaining the operation of the diagnostic imaging catheter 100.

In the present embodiment, as an example of the diagnostic imaging catheter 100, an IVUS catheter that acquires an image for intravascular ultrasound diagnosis (IVUS) will be described.

First, the diagnostic imaging catheter 100 will be outlined with reference to FIGS. 1, 2, and 3. The diagnostic imaging catheter 100 is capable of inserting a drive shaft 110 provided with an imaging unit 115 capable of acquiring image information, a sheath portion 120 having an image lumen 125 through which the drive shaft 110 can be inserted, and a guide wire 200. A guide wire lumen 135 is provided, a guide wire insertion portion 130 arranged on the outer surface on the tip side of the sheath portion 120, a base end portion 153 are arranged on the image lumen 125, and the tip portion 151 is from the image lumen 125. It has a tip member 150 arranged so as to project.

In the description of the present specification, the side inserted into the body cavity of the diagnostic imaging catheter 100 is referred to as the distal end side, the hub 190 side provided in the diagnostic imaging catheter 100 is referred to as the proximal end side, and the sheath portion 120. The stretching direction is referred to as an axial direction. In FIGS. 2 to 5, the axial direction is indicated by an arrow X, and the direction orthogonal to the axial direction and in which the sheath portion 120 and the guide wire insertion portion 130 are juxtaposed is indicated by an arrow Z. The direction orthogonal to each direction indicated by the arrow Z is indicated by the arrow Y.

Further, in the description of the embodiment, the tip portion means a certain range including the tip (leading edge) and its periphery, and the proximal end portion means a certain range including the proximal end (most proximal end) and its periphery. It shall mean a range.

Next, the overall configuration of the diagnostic imaging catheter 100 will be described.

As shown in FIGS. 1 (A), 1 (B), and 3, the drive shaft 110 includes an image lumen 125 of the sheath portion 120, an outer tube 160 connected to the proximal end side of the sheath portion 120, and an outer tube. The inside of the inner shaft 170 inserted into the 160 is inserted.

The hub 190, the inner shaft 170, and the drive shaft 110 are configured to move integrally in the axial direction.

For example, when an external drive device (not shown) moves the hub 190 toward the tip end side in the axial direction, the inner shaft 170 connected to the hub 190 is pushed into the outer tube 160 and the unit connector 181. When the hub 190 moves toward the tip end side in the axial direction, the drive shaft 110 connected to the hub 190 and the image pickup unit 115 provided on the drive shaft 110 move to the tip end side of the image lumen 125 of the sheath portion 120. ..

Further, when the external drive device moves the hub 190 toward the proximal end side, the inner shaft 170 is pulled out from the outer tube 160 and the unit connector 181 as shown by the arrow a1 in FIG. 1 (B). At this time, the drive shaft 110 and the image pickup unit 115 move to the proximal end side of the image lumen 125 of the sheath portion 120 as shown by the arrow a2 in FIG. 1 (B).

When using the diagnostic imaging catheter 100, the hub 190 is connected to an external drive device. Then, a pullback operation is performed in which the drive shaft 110 and the imaging unit 115 are moved backward toward the base end side of the sheath unit 120. At this time, the drive shaft 110 and the image pickup unit 115 are rotated (radial scanning) by the driving force provided by the external drive device. The diagnostic imaging catheter 100 acquires a tomographic image of a biological lumen (for example, a blood vessel) in the axial direction by moving the imaging unit 115 to the axially proximal side of the sheath portion 120 by a pullback operation. Can be done.

As shown in FIG. 1A, the tip of the inner shaft 170 is arranged near the relay connector 182 when the inner shaft 170 is pushed most toward the tip. The relay connector 182 is a connector for connecting the sheath portion 120 and the outer tube 160.

As shown in FIG. 1 (B), a connector 171 for preventing the inner shaft 170 from coming out of the outer pipe 160 is arranged at the tip of the inner shaft 170. The disconnection prevention connector 171 is placed in a predetermined position in the unit connector 181 when the hub 190 is pulled to the most proximal side, that is, when the inner shaft 170 is most pulled out from the outer tube 160 and the unit connector 181. It is configured to be caught.

As shown in FIG. 3, the drive shaft 110 has a flexible tube body 110a and a signal line 110b inserted inside the tube body 110a.

The tube body 110a can be composed of, for example, a multi-layer coil having different winding directions around the axis. The coil can be made of, for example, stainless steel, Ni-Ti (nickel-titanium) alloy, or the like.

The imaging unit 115 includes an ultrasonic vibrator 115a for transmitting and receiving ultrasonic waves, and a housing 115b in which the ultrasonic vibrator 115a is housed.

The ultrasonic oscillator 115a is electrically connected to the signal line 110b. The signal line 110b can be configured by, for example, a twisted pair cable, a coaxial cable, or the like. The ultrasonic vibrator 115a emits ultrasonic waves as inspection waves into the body cavity. Further, the ultrasonic vibrator 115a receives the ultrasonic waves reflected from the body cavity.

A tip member 150 is arranged on the tip side of the sheath portion 120. The tip member 150 has a function as a reinforcing member that increases the rigidity of the sheath portion 120 and prevents kink or the like from being generated in the sheath portion 120. The tip member 150 is formed with a hole 155 for discharging the priming liquid from the image lumen 125 of the sheath 120.

When using the diagnostic imaging catheter 100, a priming solution is filled in the image lumen 125 of the sheath portion 120 in order to reduce the attenuation of ultrasonic waves due to air in the sheath portion 120 and enable efficient transmission and reception of ultrasonic waves. The priming liquid filled in the image lumen 125 of the sheath portion 120 is discharged to the outside of the sheath portion 120 through the hole portion 155 of the tip member 150 together with a gas such as air staying in the image lumen 125.

As shown in FIGS. 2 and 3, a guide wire insertion portion 130 provided with a guide wire lumen 135 through which the guide wire 200 can be inserted is arranged on the outer surface of the tip portion of the sheath portion 120. Further, on the base end side of the guide wire insertion portion 130, a base end side guide wire insertion portion 140 in which the lumen 145 for the guide wire is formed is arranged.

The guide wire insertion portion 130 can be formed, for example, so as to have a tapered shape in which the wall thickness of the tip portion 131 gradually decreases toward the tip side. By forming the shape of the tip portion 131 of the guide wire insertion portion 130 as described above, the insertability of the guide wire insertion portion 130 into the narrowed portion S can be improved.

Further, the proximal end opening 133a located at the proximal end portion 133 of the guide wire insertion portion 130 can be formed, for example, in a tapered shape inclined from the distal end side toward the proximal end side toward the outer surface side of the sheath portion 120. By forming the base end opening 133a of the guide wire insertion portion 130 into the shape as described above, the guide wire 200 can be easily inserted into the guide wire lumen 135 of the guide wire insertion portion 130.

The tip opening of the base end side guide wire insertion portion 140 has, for example, a tapered shape inclined in the direction opposite to the base end opening 133a of the guide wire insertion portion 130 (direction inclining from the base end side toward the tip end side). Can be formed.

The outer diameters of the guide wire insertion portion 130 and the proximal end side guide wire insertion portion 140 can be set within a range having an inner diameter through which the guide wire 200 can be inserted from the viewpoint of suppressing an increase in the diameter of the tip portion of the diagnostic imaging catheter 100. It is preferably formed as small as possible. For example, the outer diameters of the guide wire insertion portion 130 and the proximal end side guide wire insertion portion 140 can be formed to be smaller than the outer diameter of the sheath portion 120.

The cross-sectional shape (shape of the axially orthogonal cross section) of the guide wire insertion portion 130 and the proximal end side guide wire insertion portion 140 is not particularly limited as long as the guide wire 200 can be inserted, and may be a shape other than a circle. ..

When a surgeon such as a doctor performs a procedure using the diagnostic imaging catheter 100, the guide wire 200 is attached to the guide wire lumen 135 of the guide wire insertion portion 130 and the guide wire lumen 145 of the proximal end side guide wire insertion portion 140. Is inserted. By inserting the guide wire 200 into the guide wire insertion portions 130 and 140, the operator can smoothly move the diagnostic imaging catheter 100 along the guide wire 200 to the target position (for example, the stenosis portion S) of the biological lumen. Can be delivered to (see FIG. 6).

As shown in FIG. 1A, the hub 190 is provided with a priming port 191 that communicates with the image lumen 125 of the sheath portion 120. Further, inside the hub 190, a predetermined connector (joint) that is mechanically and electrically connected to an external drive device, a connection pipe that holds the drive shaft 110, a bearing that rotatably supports the connection pipe, and the like are arranged. doing.

Next, the structure of the tip portion of the diagnostic imaging catheter 100 will be described.

As shown in FIGS. 2 and 3, the guide wire insertion portion 130 provided on the outer surface of the tip portion 121 of the sheath portion 120 is arranged so as to be inclined toward the image lumen 125 side of the sheath portion 120. .. Further, the tip portion 151 of the tip member 150 protruding from the image lumen 125 of the sheath portion 120 has a shape inclined toward the guide wire insertion portion 130 side. In FIG. 3, the direction in which the guide wire insertion portion 130 is inclined is indicated by an arrow D1, and the direction in which the tip portion 151 of the tip member 150 is inclined is indicated by an arrow D2.

The inclination angle θ1 of the guide wire insertion portion 130 shown in FIG. 4 can be formed, for example, at 2 ° to 10 °. The inclination angle θ1 is a straight line c1 parallel to the axis c2 of the sheath portion 120 and the axis b1 passing through the substantially central position of the guide wire insertion portion 130 in a state where no external force is applied to the tip portion of the diagnostic imaging catheter 100. It can be defined by the angle formed by.

The inclination angle θ2 of the tip portion 151 of the tip member 150 shown in FIG. 4 can be formed to, for example, 5 ° to 15 °. The inclination angle θ2 is such that a straight line b2 substantially parallel to the end surface 151a of the tip portion 151 of the tip member 150 and the axis c2 of the sheath portion 120 are formed in a state where no external force is applied to the tip portion of the diagnostic imaging catheter 100. It can be defined by the angle of formation.

The magnitude relationship between the inclination angle θ1 of the guide wire insertion portion 130 and the inclination angle θ2 of the tip member 150 is not particularly limited. However, if the angle difference between the inclination angle θ1 of the guide wire insertion portion 130 and the inclination angle θ2 of the tip member 150 becomes excessively large, it may not be possible to effectively enhance the insertability into the narrowed portion S. Therefore, the angle difference between the inclination angle θ1 of the guide wire insertion portion 130 and the inclination angle θ2 of the tip member 150 is preferably within the range of, for example, 0 ° to 13 °.

The inclination angle θ2 of the tip member 150 can be set relatively easily by adjusting the shape of the tip member 150. On the other hand, since the inclination angle θ1 of the guide wire insertion portion 130 is adjusted by the arrangement (orientation) of the guide wire insertion portion 130, it is difficult to set it to a steep angle (for example, an angle close to 90 °). is there. Therefore, for example, the angle difference between the inclination angles θ1 and θ2 can be adjusted by keeping the inclination angle θ1 of the guide wire insertion portion 130 constant within a certain range and adjusting the inclination angle θ2 of the tip member 150 as appropriate. It can be done relatively easily.

The shape (outer shape and cross-sectional shape) of the tip member 150 is not particularly limited as long as the tip portion 151 inclined toward the guide wire insertion portion 130 side is formed. For example, the end surface 151a of the tip portion 151 of the tip member 150 may have a shape that extends linearly in the cross section shown in FIG. 3, or a shape that is convexly curved toward the tip end side or the base end side of the sheath portion 120. It may be.

The axial length of the tip portion 151 of the tip member 150 (the axial length of the portion of the sheath portion 120 protruding from the image lumen 125) can be formed, for example, 2 mm to 4 mm. Further, the axial length of the base end portion 153 of the tip member 150 (the axial length of the portion of the sheath portion 120 arranged in the image lumen 125) can be formed, for example, 0.5 mm to 2 mm. ..

As shown in FIGS. 4 and 5, the guide wire insertion portion 130 includes a tip portion 131 arranged on the tip side of the tip portion 150 (a portion protruding toward the tip side of the sheath portion 120) of the tip member 150. An intermediate portion 132 located on the proximal end side of the distal end portion 131 and vertically overlapped with the distal end portion 151 of the advanced member 150, and an intermediate portion 132 located on the proximal end side of the intermediate portion 132 and the tip of the sheath portion 120. It has a base end portion 133 which is arranged so as to overlap with the portion 121 in the axial direction.

As shown in FIG. 4, in the region A2 where the intermediate portion 132 of the guide wire insertion portion 130 is arranged, the tip portion 151 of the tip member 150 is arranged along a part of the outer surface of the guide wire insertion portion 130 in the circumferential direction. Will be done. Further, in the region A3 where the base end portion 133 of the guide wire insertion portion 130 is located, the sheath portion 120 having an outer diameter larger than that of the guide wire insertion portion 130 overlaps with the guide wire insertion portion 130 in the axial direction. Therefore, the outer shape of the diagnostic imaging catheter 100 shown in FIG. 5 (the outer shape in the plan view seen from the direction of arrow 5A in FIG. 4) is the position where the tip 131 of the guide wire insertion portion 130 is arranged (region A1). ), The position where the intermediate portion 132 of the guide wire insertion portion 130 is arranged (region A2), and the region where the base end portion 133 of the guide wire insertion portion 130 is arranged (A3). In other words, the magnitude relationship of the outer shape means the magnitude relationship of the dimensions W1 to W3 shown in FIG.

The outer shape of the tip of the diagnostic imaging catheter 100 is from the tip side to the base end side according to the positions where the tip portion 131, the intermediate portion 132, and the proximal end portion 133 of the guide wire insertion portion 130 are arranged as described above. The shape becomes larger. Therefore, the diagnostic imaging catheter 100 can easily enter the narrowed portion S from the distal end side of the guide wire insertion portion 130, so that the insertability into the narrowed portion S is improved.

Further, in the region A2 where the intermediate portion 132 of the guide wire insertion portion 130 is arranged, the intermediate portion 132 and the tip member 150 are arranged so as to be overlapped in the axial direction. Therefore, the region A2 has a higher rigidity than the region A1 in which only the tip portion 131 of the guide wire insertion portion 130 is arranged. Further, in the region A3 where the base end portion 133 of the guide wire insertion portion 130 is arranged, the base end portion 133, the tip member 150, and the sheath portion 120 are arranged so as to be overlapped in the axial direction. Therefore, the region A3 has a higher rigidity than the region A2. As described above, the diagnostic imaging catheter 100 has increased rigidity from the distal end side to the proximal end side according to the positions where the respective portions 131, 132, 133 of the guide wire insertion portion 130 are arranged, and therefore, in each portion in the axial direction. It is possible to suppress the occurrence of a sudden difference in physical properties, and it is possible to preferably prevent the occurrence of kink or the like on the tip side of the sheath portion 120.

In particular, in the present embodiment, since the wall thickness of the tip portion 151 of the tip member 150 gradually increases from the tip end side to the base end side, the intermediate portion 132 of the guide wire insertion portion 130 is arranged. The rigidity changes relatively gently from the region A2 to the region A3 where the base end portion 133 of the guide wire insertion portion 130 is arranged. Therefore, the diagnostic imaging catheter 100 can more preferably prevent the occurrence of kink or the like on the distal end side of the sheath portion 120.

The axial length L1 of the region A1 shown in FIG. 4 can be formed to, for example, 0.5 mm to 2 mm. The axial length L2 of the region A2 can be formed, for example, 1 mm to 3 mm. The axial length L3 of the region A3 can be formed, for example, from 0.5 mm to 2 mm.

From the viewpoint of improving the insertability of the diagnostic imaging catheter 100 into the narrowed portion, it is preferable to form the length L1 of the region A1 longer. However, if the region A1 is formed extremely long, the guide wire insertion portion 130 is likely to break or fall off. Therefore, for example, when the region A1 is formed to be relatively long, the length of the region A2 is about the same as that of the region A1. It is preferable to increase the contact area (fixed area) between the tip member 150 and the guide wire insertion portion 130. In this case, the length L3 of the region A3 can be formed shorter than, for example, the length L1 of the region A1 and L2 of the region A2.

As shown in FIG. 4, the guide wire insertion portion 130 is fixed to the tip portion 151 of the tip member 150 protruding from the image lumen 125 of the sheath portion 120 and the tip portion 121 of the sheath portion 120. Further, the tip portion 151 of the tip member 150 is fixed to the outer surface of the intermediate portion 132 of the guide wire insertion portion 130. Further, the base end portion 153 of the tip member 150 is fixed to the sheath portion 120 in the image lumen 125 of the sheath portion 120.

As described above, the guide wire insertion portion 130 is fixed to both the tip member 150 and the sheath portion 120. Further, the tip member 150 is fixed to both the guide wire insertion portion 130 and the sheath portion 120. That is, each of the guide wire insertion portion 130, the tip member 150, and the sheath portion 120 is fixed to the two other members to be fixed. Therefore, in the diagnostic imaging catheter 100, the fixing force between the three members of the guide wire insertion portion 130, the tip member 150, and the sheath portion 120 is suitably improved.

Further, the tip member 150 has a function as a fixing member for fixing the guide wire insertion portion 130 and the sheath portion 120 over a certain range in the axial direction. For this reason, the tip member 150 has a kink at the boundary portion between the guide wire insertion portion 130 and the sheath portion 120 (the portion that transitions from the position where both members do not overlap to the position where they overlap in the axial direction) where the difference in physical characteristics tends to be relatively large. It can be suitably prevented from occurring.

The method of fixing each member of the guide wire insertion portion 130, the tip member 150, and the sheath portion 120 is not particularly limited, and for example, adhesion or fusion can be adopted. When the tip member 150, the guide wire insertion portion 130, and the sheath portion 120 are fixed by fusion, the guide wire insertion portion 130 and the sheath portion 120 can be more firmly fixed via the tip member 150.

As shown in FIGS. 2 and 3, the tip opening 121a formed at the tip of the sheath 120 is tilted toward the side opposite to the direction in which the tip 151 of the tip member 150 is tilted (the direction indicated by the arrow D2). doing. That is, the tip opening 121a of the sheath portion 120 is inclined from the tip side toward the base end side.

Since the tip opening 121a of the sheath portion 120 has the above-mentioned shape, the shape of the tip 151 (the shape of the end face 151a) of the tip member 150 protruding from the tip opening 121a is changed to the shape of the tip opening 121a. It becomes easy to form a tapered shape from the lower side (lower side in FIG. 3) to the upper side (upper side in FIG. 3 where the guide wire insertion portion 130 is arranged). Further, since the amount (exposed area) that the tip portion 151 of the tip member 150 is exposed to the upper side of the tip opening portion 121a can be relatively large, the contact area between the tip member 150 and the guide wire insertion portion 130 is increased. It is possible to increase the fixing force between the two.

The sheath portion 120, the guide wire insertion portion 130, and the tip member 150 can be formed of, for example, a known resin material. Examples of the resin material include polyethylene, polypropylene, polyisoprene, chlorinated polyethylene, polyvinyl chloride, polybutadiene, polystyrene, impact resistant polystyrene, acrylonitrile-styrene resin (AS resin), and acrylonitrile-butadiene-styrene resin (ABS resin). , Methylmethacrylate-butadiene-styrene resin (MBS resin), methylmethacrylate-acrylonitrile-butadiene-styrene resin (MABS resin), acrylonitrile-acrylic rubber-styrene resin (AAS resin), acrylic resin, polyester (polyethylene terephthalate, polybutylene terephthalate) , Polyethylene naphthalate, etc.), Polycarbonate, polyphenylene ether, modified polyphenylene ether, aliphatic polyamide, aromatic polyamide, polyphenylene sulfide, polyimide, polyether ether ketone, polysulfone, polyarylate, polyether ketone, polyether nitrile, polythioether sulfone , Polyethersulfone, Polybenzimidazole, Polyamideimide, Polyetherimide, Polyacetal, Liquid crystal polymer, Thermoplastic polyurethane and the like. The sheath portion 120, the guide wire insertion portion 130, and the tip member 150 may be formed of different materials or may be formed of the same material.

Next, the operation of the diagnostic imaging catheter 100 according to the present embodiment will be described.

As shown in FIG. 6, a surgeon such as a doctor delivers a diagnostic imaging catheter 100 along a guide wire 200 inserted prior to a stenosis S formed in a biological lumen B such as a blood vessel. .. At this time, the operator inserts the guide wire 200 into the guide wire lumen 135 of the guide wire insertion portion 130 and the guide wire lumen 145 of the proximal end side guide wire insertion portion 140.

For example, when the guide wire insertion portion 130 is not arranged so as to be inclined toward the sheath portion 120 side, the guide wire insertion portion 130 maintains its shape so as to extend linearly due to the rigidity of the guide wire 200. Therefore, it becomes difficult to smoothly insert the guide wire insertion portion 130 side into the inner peripheral side (inner surface side) of the narrowed portion S. In particular, in the diagnostic imaging catheter provided with the proximal side guide wire insertion portion 140, the rigidity of the guide wire 200 arranged substantially linearly from the proximal end side guide wire insertion portion 140 toward the proximal end side guide wire insertion portion 140. Due to the influence, the guide wire insertion portion 130 is straightened more firmly and linearly. Therefore, the decrease in the insertability of the diagnostic imaging catheter 100 into the narrowed portion S becomes even more remarkable.

In response to the above problems, the diagnostic imaging catheter 100 of the present embodiment is inclined so that the guide wire insertion portion 130 and the tip member 150 face each other. Therefore, when the operator inserts the tip of the diagnostic imaging catheter 100 into the stenosis S, the operator easily allows the guide wire insertion portion 130 side and the tip member 150 side to enter the inner peripheral side of the stenosis portion S. be able to. Further, the guide wire 200 inserted through the guide wire insertion portion 130 directs the direction of the guide wire insertion portion 130 toward the inner peripheral side of the narrowed portion S due to its rigidity. Therefore, the tip end portion of the diagnostic imaging catheter 100 can enter the inner peripheral side of the stenosis portion S more smoothly.

As described above, the diagnostic imaging catheter 100 according to the present embodiment has a sheath portion including a drive shaft 110 provided with an imaging unit 115 capable of acquiring image information and an image lumen 125 through which the drive shaft 110 can be inserted. A guide wire lumen 135 through which the guide wire 200 can be inserted is provided, and a guide wire insertion portion 130 and a base end portion 153 arranged on the outer surface on the tip end side of the sheath portion 120 are arranged on the image lumen 125. The tip member 150 is arranged so that the tip portion 151 projects from the image lumen 125. The guide wire insertion portion 130 is arranged so as to be inclined toward the image lumen 125 side of the sheath portion 120, and the tip portion 151 of the tip member 150 is inclined toward the guide wire insertion portion 130 side. There is.

The diagnostic imaging catheter 100 configured as described above is inclined toward the distal end side so that the guide wire insertion portion 130 and the distal end member 150 face each other. Therefore, the diagnostic imaging catheter 100 has improved insertability into the narrowed portion S. Further, the guide wire insertion portion 130 is oriented so as to be inclined toward the tip end side by being arranged so as to be inclined toward the image lumen 125 side of the sheath portion 120. Therefore, the diagnostic imaging catheter 100 does not need to have an excessively small wall thickness of the guide wire insertion portion 130 in order to impart a tapered shape. As a result, the diagnostic imaging catheter 100 can suitably maintain the pushability with respect to the narrowed portion S.

Further, the guide wire insertion portion 130 is located on the tip end side of the tip end member 150 on the tip end side of the tip end portion 151 and on the base end side of the tip end portion 131, and is located on the tip end portion 151 and the shaft of the tip end member 150. It has an intermediate portion 132 which is arranged so as to be overlapped in the direction, and a base end portion 133 which is located on the proximal end side of the intermediate portion 132 and is arranged so as to be overlapped with the tip end portion 121 of the sheath portion 120 in the axial direction. There is. The diagnostic imaging catheter 100 has a position where the tip 131 of the guide wire insertion portion 130 is arranged (region A1), a position where the intermediate portion 132 is arranged (region A2), and a position where the proximal end portion 133 is arranged. The outer shape increases in the order of (region A3).

The diagnostic imaging catheter 100 configured as described above has a larger outer shape from the distal end side to the proximal end side in the order of the distal end portion 131, the intermediate portion 132, and the proximal end portion 133 of the guide wire insertion portion 130. The wire insertion portion 130 can be easily pushed into the narrowed portion S from the tip end side, and the insertability into the narrowed portion S is improved. Further, the diagnostic imaging catheter 100 has an increased rigidity from the distal end side to the proximal end side according to the positions where the respective portions 131, 132, 133 of the guide wire insertion portion 130 are arranged, so that a sharp difference in physical properties occurs. It is possible to prevent the occurrence of kink or the like on the tip end side of the sheath portion 120.

Further, the guide wire insertion portion 130 is fixed to the tip portion 151 of the tip member 150 protruding from the image lumen 125 of the sheath portion 120 and the tip portion 121 of the sheath portion 120. Therefore, the fixing force between the three members of the guide wire insertion portion 130, the tip member 150, and the sheath portion 120 can be suitably improved.

Further, the tip opening 121a formed in the tip 121 of the sheath 120 is inclined toward the side opposite to the direction in which the tip 151 of the tip member 150 is tilted. Therefore, the shape of the tip portion 151 of the tip member 150 protruding from the tip opening portion 121a can be easily formed into a tapered shape that is inclined toward the guide wire insertion portion 130 side. Further, the contact area between the tip portion 151 of the tip member 150 and the guide wire insertion portion 130 can be increased, and the fixing force between the two can be increased.

Further, the diagnostic imaging catheter 100 includes a guide wire lumen 145 through which the guide wire 200 can be inserted, is located on the proximal end side of the guide wire insertion portion 130, and is arranged on the outer surface of the sheath portion 120. It has a base end side guide wire insertion portion 140. Since the diagnostic imaging catheter 100 is inclined toward the tip side so that the guide wire insertion portion 130 and the tip member 150 face each other, the guide wire 200 is inserted through the guide wire insertion portions 130 and 140, respectively. However, the insertability into the narrowed portion S is preferably maintained.

Although the medical device according to the present invention has been described above through the embodiments, the present invention is not limited to the configuration described in the embodiments and can be appropriately modified based on the description of the claims. Is.

As a medical device, an IVUS catheter has been described as an example, but the medical device has, for example, functions of both an optical interference tomographic diagnostic device, an intravascular ultrasonic diagnostic apparatus, and an optical interference tomographic diagnostic apparatus. It can also be applied to a dual type diagnostic imaging catheter that can be switched or used at the same time, a diagnostic imaging catheter that uses an optical frequency region imaging method, and the like. Further, the configuration and the like of each part of the medical device are not limited to those described in the illustration, and can be changed as appropriate.

100 Diagnostic Imaging Catheter (Medical Device),
110 drive shaft,
120 sheath part,
121 The tip of the sheath,
121a Sheath tip opening,
125 image lumens,
130 guide wire insertion part,
131 Tip of guide wire insertion part,
132 Middle part of guide wire insertion part,
133 Guide wire insertion part base end,
135 Lumens for guide wires,
140 Base end side guide wire insertion part,
145 Lumens for guide wires,
150 tip member,
151 Tip of tip member,
153 Base end of tip member,
200 guide wire,
θ1 Inclination angle of guide wire insertion part,
θ2 Tilt angle of tip member,
B biological lumen,
S stenosis.

Claims (5)

A medical device for acquiring images of biological cavities,
A drive shaft equipped with an imaging unit that can acquire image information,
A sheath portion having an image lumen through which the drive shaft can be inserted, and a sheath portion.
A guide wire lumen through which the guide wire can be inserted is provided, and a guide wire insertion portion arranged on the outer surface on the tip side of the sheath portion and a guide wire insertion portion are provided.
It has a tip member whose base end portion is arranged in the image lumen and whose tip end portion is arranged so as to protrude from the image lumen.
The guide wire insertion portion is arranged so as to be inclined toward the image lumen side of the sheath portion.
The tip portion of the tip member is inclined toward the guide wire insertion portion side, and is exposed from the image lumen to the proximal end side of the sheath portion with respect to the guide wire insertion portion. Medical device in contact. The guide wire insertion portion is located on the tip end side arranged on the tip end side of the tip end member and on the proximal end side of the tip end portion, and is arranged so as to overlap the tip end portion of the tip member in the axial direction. It has a base end portion that is located on the proximal end side of the intermediate portion and is arranged so as to overlap the tip end portion of the sheath portion in the axial direction.
According to claim 1, the medical device has a larger outer shape in the order of the position where the tip portion of the guide wire insertion portion is arranged, the position where the intermediate portion is arranged, and the position where the base end portion is arranged. The medical device described. The medical use according to claim 1 or 2, wherein the guide wire insertion portion is fixed to the tip end portion of the tip member and the tip end portion of the sheath portion protruding from the image lumen of the sheath portion. device. The medical device according to claim 3, wherein the tip member, the guide wire insertion portion, and the sheath portion are fixed by fusion. A claim that includes a lumen for a guide wire through which a guide wire can be inserted, and further has a base end side guide wire insertion portion that is closer to the proximal end side than the guide wire insertion portion and is arranged on the outer surface of the sheath portion. Item 2. The medical device according to any one of Items 1 to 4.

Images