JP6540956B2 - Ultrasound endoscope dilator - Google Patents

Description

  The present invention relates to a dilator used to perform a procedure involving dilation of a puncture formed in body tissue under an ultrasonic endoscope.

  In recent years, in cases of unresectable malignant biliary stricture or obstruction requiring biliary drainage, in cases where transduodenal papillary approach is not possible, etc., endoscopic ultrasound guided biliary drainage (EUS-BD) There are sporadic reports of enforcement. EUS-BD inserts an ultrasound endoscope into the duodenum (or stomach) and punctures the common bile duct (or intrahepatic bile duct) with a puncture needle from the duodenal (or stomach) wall while observing an ultrasound image in real time And placing a stent so as to bridge the puncture hole in the duodenum (or stomach) wall and the puncture hole in the common bile duct (or intrahepatic bile duct) in the body cavity. This procedure allows biliary drainage to the duodenum (or stomach) through the stent.

  For example, when a stomach and an intrahepatic bile duct are bypassed with a stent, a puncture needle is punctured from the inner wall of the stomach to the bile duct, a guide wire is inserted to secure a route, and a stent of a stent delivery device is used. After dilating the puncture hole of the stomach and bile duct with the dilator to the extent that the distal end of the attached catheter part can be inserted, the distal end (stent placement part) of the catheter part is inserted into the expanded puncture hole And place the stent over the expanded puncture.

  A dilator (dilator tube) as an endoscope treatment tool for expanding a puncture hole formed by a puncture needle under an ultrasonic endoscope is a flexible elongated tube having a lumen through which a guide wire is inserted. In order to mechanically push the puncture hole and gradually expand it, the distal end portion thereof has a tapered portion formed in a tapered manner. The surface of the distal end portion (a portion inserted into the puncture hole and a portion in the vicinity thereof) including at least the tapered portion of the dilator tube is formed smooth in order to ensure smooth insertion into the puncture hole. In EUS-BD, since the procedure is performed referring to X-ray images in addition to ultrasound images, a contrast marker made of an X-ray opaque material such as metal is provided at the tip of the dilator. It is done.

Japanese Patent Application Publication No. 2012-513286

  By the way, when pressing the dilator into the puncture hole while observing an ultrasonic image, it is necessary to accurately recognize the position of the tip of the dilator. However, from the relationship between the dilator and tissue in vivo, the ultrasonic wave In the image, the visibility of the tip of the dilator may not be sufficient.

  In addition, as a technique for improving the ultrasonic visibility of the outer needle (a needle with a needle cap) used for puncturing internal tissues, as described in Patent Document 1, a needle (stylet) or a needle needle (cannula) Although it is known to provide a dimple, dip or the like at the tip of), this technique does not relate to a dilator for expanding the puncture hole.

  The present invention has been made in view of these points, and it is an object of the present invention to provide a dilator for an ultrasonic endoscope with improved ultrasonic visibility.

A dilator for an ultrasonic endoscope according to the present invention is
Ultrasonic wave comprising a flexible tube having a tapered portion at its distal end portion, an expanded portion having a straight body portion near the proximal end side of the tapered portion, and a lumen into which a guide wire is slidably inserted It is a dilator for endoscopes.
A rough surface is provided on all or part of the extended portion.

In a dilator for an ultrasonic endoscope according to the present invention,
The rough surface may be provided on all or part of the outer surface of the extension.

In a dilator for an ultrasonic endoscope according to the present invention,
An annular contrast marker externally or internally fitted to the extension;
The rough surface may be provided on the outer surface of the contrast marker.

In a dilator for an ultrasonic endoscope according to the present invention,
The said rough surface can be set in 0.5-5.0 micrometers in arithmetic mean surface roughness (Ra).

  According to the present invention, it is possible to obtain a dilator for an ultrasonic endoscope excellent in ultrasonic wave visibility.

It is a top view which shows the structure of the dilator of 1st Embodiment of this invention. It is sectional drawing cut | disconnected in terms of including the central axis which shows the principal part structure of the dilator of 1st Embodiment of this invention. It is sectional drawing cut | disconnected by the surface orthogonal to the central axis which shows the principal part structure of the dilator of 1st Embodiment of this invention. It is a perspective view of the imaging marker of the dilator of 1st Embodiment of this invention. It is a figure which shows the manufacturing process of the dilator of 1st Embodiment of this invention. It is a figure which shows the manufacturing process of the dilator of 1st Embodiment of this invention. It is a figure which shows the metal mold | die used at the manufacturing process of the dilator of 1st Embodiment of this invention. It is a figure which shows the manufacturing process of the dilator of 1st Embodiment of this invention. It is a top view which shows the structure of the dilator of 2nd Embodiment of this invention. It is sectional drawing cut | disconnected in terms of including the central axis which shows the principal part structure of the dilator of 2nd Embodiment of this invention. It is sectional drawing cut | disconnected by the surface orthogonal to the central axis which shows the principal part structure of the dilator of 2nd Embodiment of this invention. It is a perspective view of the imaging marker of the dilator of 2nd Embodiment of this invention. It is a top view which shows the structure of the dilator of 3rd Embodiment of this invention. It is a figure which shows the metal mold | die used at the manufacturing process of the dilator of 3rd Embodiment of this invention. It is a figure which shows the manufacturing process of the dilator of 3rd Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings. In the following, an ultrasound endoscope-guided transgastric transhepatic biliary drainage (EUS-HGS), that is, a procedure for bypassing the stomach and an intrahepatic bile duct under an ultrasound endoscope guide, the gastric wall and the intrahepatic The dilator used to dilate the puncture hole provided in the bile duct wall (liver) will be described as an example.

  However, the application of the dilator according to the present invention is not limited to the use for expanding the puncture hole provided in the stomach wall and the intrahepatic bile duct wall (liver), and provided in various organs under the ultrasound endoscope guide. The present invention can be widely applied to the use for expanding a puncture hole or a narrowed portion of various body lumens.

  In the following, a dilator optimized when using a 0.035 inch (直径 0.889 mm) diameter guide wire will be described as an example. However, it is needless to say that the guide wire may be optimized in the case of using the one having a diameter of 0.025 inch or the one having another diameter.

First Embodiment
A first embodiment of the present invention will be described with reference to FIGS. A dilator 1 for an ultrasonic endoscope according to a first embodiment of the present invention is a dilator comprising an elongated tube inserted into a body (a lumen) of a patient via a treatment instrument guide tube of an endoscope (not shown). An operation unit 12 is connected to the proximal end side of the tube 11 and the dilator tube 11 and configured to be gripped by the operator when operating the dilator tube 11 in the body from the outside of the body.

  The dilator tube 11 is made of a flexible elongated tube, and has a lumen 11a through which a guide wire (not shown) is inserted. The diameter (diameter) of the lumen 11a of the dilator tube 11 is not particularly limited as long as it is a diameter larger than the outer diameter of the guide wire inserted into the lumen 11a, but at least at the tip (distal end) of the dilator tube 11 Is preferably slightly larger than the outer diameter of the guide wire used from the viewpoint of improving the insertability into the puncture hole. In the present embodiment, the diameter (diameter) of the inner cavity 11a of the dilator tube 11 is set to 0.93 mm in the vicinity of the tip (where the thermoforming to be described later is applied), and the portion on the proximal end side The setting is 1.10 mm.

  The outer diameter of the dilator tube 11 is set to such a diameter that the puncture hole formed in the body tissue can be expanded to a desired diameter by the puncture needle, and may be set in the range of 1.20 to 3.50 mm, for example. it can. In the present embodiment, the outer diameter of the dilator tube 11 is set to 2.45 mm (7 Fr). The length of the dilator tube 11 can be set, for example, in the range of 1500 to 2500 mm, and is set to 1800 mm in this embodiment.

  The distal end portion (distal end portion) of the dilator tube 11 is provided with a tapered portion 11b which is tapered so as to become thinner toward the distal end (distal end). The tapered portion 11b gradually expands the puncture hole formed in the body tissue, and contributes to the expansion of the puncture hole in the vicinity of the distal end side (distal end side) of the straight trunk portion continuous with the taper portion 11b. To smoothly guide the portion) into the puncture hole. Note that the tapered portion 11 b and a portion (proximal end straight body portion) 11 d in the vicinity of the distal end side (distal end side) of the straight body portion continuous with the tapered portion 11 b expand the puncture hole formed in the body tissue It becomes a part.

  Although not particularly limited, in the present embodiment, the distal end portion of the tapered portion 11b is provided with a straight barrel end straight body portion 11c whose diameter does not change. The dimension (length) of the tapered portion 11b can be set, for example, in the range of 5.0 to 20.0 mm, and in the present embodiment, it is set to 11.5 mm. The dimension (length) of the front end straight body portion 11c can be set, for example, in the range of 1.00 to 3.00 mm.

  At the proximal end of the dilator tube 11, a gripping member constituting the operation unit 12 is attached. The holding member has a through hole (not shown) penetrating in the axial direction, and the through hole is in communication with the bore 11 a of the dilator tube 11.

  Examples of the material of the dilator tube 11 include polyolefins such as polyethylene and polypropylene, polyvinyl chloride, polyurethane, ethylene-vinyl acetate copolymer, polyesters such as polyethylene terephthalate and polybutylene terephthalate, polyamide, polyether polyamide, polyester polyamide, Various thermoplastic resin materials such as polyetheretherketone (PEEK), polyetherimide, fluorine resin such as polytetrafluoroethylene and tetrafluoroethylene / hexafluoropropylene copolymer, polystyrene type, polyolefin type, polyurethane type, It is possible to use various thermoplastic elastomers such as polyesters, polyamides and polybutadienes. Two or more of these may be used in combination.

  The dilator tube 11 is a relatively hard material (a material having a high Shore hardness) at least at the tapered portion 11b and the portion on the distal end side thereof from the viewpoint of perforability or penetration into body tissue. It is preferable to use In the present embodiment, polypropylene, which is a relatively hard material, is used as a material of which the entire dilator tube 11 is made.

  Near the distal end (tip) of the dilator tube 11, a contrast marker 13 is provided. In the present embodiment, the contrast marker 13 is an annular ring member, and is inserted into the lumen 11 a of the dilator tube 11 at a position proximal to the distal end of the dilator tube 11 by a predetermined size. (Inset). The position of the contrast marker 13 is detected by X-ray fluoroscopy to be a marker in the body, and, for example, a metal material such as gold, platinum, or tungsten, or an X-ray such as a polymer in which barium sulfate or bismuth oxide is blended. It is formed of an impermeable material. In the present embodiment, a platinum-iridium alloy (PtIr) is used.

  A rough surface 13a is provided on the outer surface of the contrast marker 13 by forming fine irregularities (see FIG. 4). The fine asperities constituting the rough surface 13a of the outer surface of the contrast marker 13 can be formed, for example, using a barrel polishing method. In barrel polishing, the object to be processed and media (abrasive material) are placed in a barrel container, and if necessary, compound, water, etc. are added to give a rotational movement or vibration to the barrel container. It is a processing method to roughen the surface of the object.

  The method of forming the fine irregularities forming the rough surface 13a is not limited to such a barrel polishing method, and a blasting method may be employed. In the blasting method, small particles like sand (granular abrasives consisting of iron, glass, alumina, etc.) are pressed against the object to be processed by pressure such as compressed air, and the surface is textured (fruit (A rough state like the surface of a pear). In addition, as a formation method of fine unevenness which constitutes rough surface 13a, it is formed by scraping off the surface irregularly by chemical surface treatment such as etching, or using sand paper or a metal brush etc. It is also good.

  The outer diameter of the contrast marker 13 is set to a diameter that can be inserted into the lumen 11 a of the dilator tube 11 and is set to 1.12 mm in the present embodiment. The inner diameter of the contrast marker 13 is set to 1.00 mm in the present embodiment. The axial length of the contrast marker 13 is set to 3.0 mm in the present embodiment.

  The surface roughness of the rough surface 13a of the contrast marker 13 can be set in the range of 0.5 to 5.0 μm in terms of arithmetic mean roughness (Ra), and in the present embodiment, it is in terms of arithmetic mean roughness (Ra) The ring member before surface processing of 0.1 μm is barrel-processed to use a surface roughness of 2.5 μm in arithmetic average roughness (Ra).

  The position where the contrast marker 13 (i.e., the rough surface 13a) is provided is a tapered portion 11b and a portion (proximal straight body portion) 11d near the distal end side (distal end side) of a straight body portion continuous with the tapered portion 11b. No particular limitation is imposed on the extension portion, but in the present embodiment, the distal end of the contrast marker 13 is disposed so as to substantially coincide with the boundary between the tapered portion 11b and the proximal straight body portion 11d. There is.

  Next, a method of manufacturing the dilator tube 11 according to the first embodiment will be described with reference to FIGS. First, as shown in FIG. 5, a straight tube 14 serving as a base material of the dilator tube 11 is prepared, and the contrast marker 13 is inserted into the lumen through the opening at the distal end (tip) thereof. (Press fit) and push it into position as shown in FIG. As the predetermined position, for example, the distal end of the contrast marker 13 can be set to a position in the range of 3.0 to 10.0 mm from the distal end of the tube 14, and in the present embodiment, 5 The position is set to .0 mm.

  Then, using a tip mold 15 as shown in FIG. 7, the distal end of the tube 14 into which the contrast marker 13 is inserted is molded. The tip molding die 15 has a lumen 15a set to have substantially the same diameter as the outer diameter of the tube 14 from one end (right side in FIG. 7) and a tube from the other end (left side in FIG. 7) A lumen 15c set to a diameter smaller than 14 (approximately the same diameter as the tip outer diameter of the tapered portion 11b to be formed (the outer diameter of the tip straight body portion 11c)) and a lumen connecting these in a tapered shape And 15b. Further, although not shown, a heater for heating the mold 15 is provided inside the mold 15.

  In molding the tip, as shown in FIG. 8, a lot bar 16 is inserted into the lumen of the tube 14 into which the contrast marker 13 has been inserted. The lot bar 16 is for suppressing the collapse of the lumen when the tip of the tube 14 is molded by the mold 15. The lot bar 16 is an elongated cylindrical member made of metal or the like, and the outer diameter thereof is set to be substantially the same as the diameter (diameter) of the lumen 11a to be secured in the dilator tube 11 after molding. In this embodiment, it is 0.93 mm.

  When the tip of the tube 14 into which the lot bar 16 is inserted is inserted into the inner cavity 15a of the mold 15, the tip of the tube 14 is heated by the heat of the heater of the mold 15 and softened. It enters along the shape of lumen 15b. The distal end of the tube 14 is formed into a tapered shape by the lumen 15b by pushing the tube 14 by a preset pushing amount (for example, 7.5 mm), and the tip reaches the inside of the lumen 15c and the tip straight barrel portion Is formed. In this state, by pulling out the tube 14 from the mold 15 or by opening the mold 15, the dilator tube 11 having the tapered portion 11b and the tip straight barrel 11c on the tip side is manufactured. .

  When the outer surface unprocessed (arithmetic mean surface roughness (Ra) 0.1 μm) is used as the contrast marker 13 (when the rough surface 13a is not provided), the outer surface of the image is formed into a textured shape by barrel processing. The ultrasonic image is compared with the case where the roughened surface 13a is provided (arithmetic mean surface roughness (Ra) 2.5 μm), and the visibility is slightly slight in the case where the roughened surface 13a is provided. But it has improved.

  According to the first embodiment described above, since the rough surface 13a is provided on the outer surface of the contrast marker 13 inserted into the lumen 11a of the dilator tube 11, the insertability of the dilator tube 11 into the body tissue (puncture hole) Ultrasonic visibility can be improved without inhibiting the

  Next, a stent placement procedure using the dilator 1 of the first embodiment will be briefly described. For example, when the stomach and the intrahepatic bile duct are bypassed, the puncture needle is punctured from the inner wall of the stomach to the bile duct, a puncture hole is formed in each wall surface, and the puncture hole is formed through the lumen of the puncture needle. Pass the guide wire to secure the route.

  Then, after the puncture needle is removed, the dilator 1 is inserted along the guide wire while observing the ultrasonic image and, if necessary, the X-ray image to expand the puncture hole. At this time, since the rough surface 13a is provided on the outer surface of the contrast marker 13 fitted in the dilator tube 11, the movement of the tip of the dilator tube 11 can be clearly recognized on the ultrasonic image. Thereafter, in place of the dilator 1, a stent is delivered using a stent delivery device.

  The stent delivery apparatus includes an inner sheath, an outer sheath, and a stent, and the stent is disposed on the stent placement portion of the inner sheath and the distal end of the outer sheath is in contact with the proximal end of the stent. Insert them along the guide wire, insert the inner sheath and stent into the punctured hole expanded by the dilator 1, and place the stent between the stomach and the bile duct. The stent is placed by removing the sheath and the outer sheath.

Second Embodiment
Next, a second embodiment of the present invention will be described with reference to FIGS. The ultrasonic endoscope dilator 2 according to the second embodiment includes a dilator tube 21 consisting of an elongated tube inserted into the body (a lumen) of a patient via a treatment instrument guiding tube (not shown) of the endoscope and It is connected to the proximal end side of the dilator tube 21, and is roughly provided with the operation part 22 for an operator to grasp, when operating the dilator tube 21 in a body from the body outside.

  The dilator tube 21 is made of a flexible elongated tube, and has a lumen 21 a through which a guide wire (not shown) is slidably inserted. The diameter (diameter) of the lumen 21a of the dilator tube 21 is not particularly limited as long as it is a diameter larger than the outer diameter of the guide wire inserted into the lumen 21a, but at least at the tip (distal end) of the dilator tube 21 Is preferably slightly larger than the outer diameter of the guide wire used from the viewpoint of improving the insertability into the puncture hole. In the present embodiment, the diameter (diameter) of the inner cavity 21a of the dilator tube 21 is set to 0.93 mm in the vicinity of the tip (where the thermoforming is applied), and in the portion on the proximal end side It is set to 1.10 mm.

  The outer diameter of the dilator tube 21 is set to a diameter that can expand the puncture hole to a desired diameter, and can be set in the range of 1.20 to 3.50 mm, for example, 2.45 mm in the present embodiment. It is set to (7 Fr). The length of the dilator tube 21 can be set, for example, in the range of 1500 to 2500 mm, and is set to 1800 mm in this embodiment.

  The distal end portion (distal end portion) of the dilator tube 21 is provided with a tapered portion 21b which is formed to be tapered toward the distal end (distal end). The tapered portion 21b gradually expands the puncture hole formed in the body tissue, and contributes to the expansion of the puncture hole in the vicinity of the distal end side (distal end side) of the straight trunk portion continuous with the taper portion 21b. Part) for smoothly guiding 21 d into the puncture hole. Note that the tapered portion 21b and a portion (proximal end straight body portion) 21d in the vicinity of the distal end side (distal end side) of the straight body portion continuous with the tapered portion 21b expand the puncture hole formed in the body tissue It becomes a part.

  Although not particularly limited, in the present embodiment, the distal end portion of the distal end tapered portion 21b is provided with a distal end straight body portion 21c of a straight barrel whose diameter does not change. The dimension (length) of the tapered portion 21 b can be set, for example, in the range of 5.0 to 20.0 mm, and in the present embodiment, it is set to 11.5 mm. In addition, the dimension (length) of the front end straight body portion 21c can be set, for example, in the range of 1.00 to 3.00 mm.

  At the proximal end of the dilator tube 21, a gripping member constituting the operation unit 22 is attached. The holding member has a through hole (not shown) penetrating in the axial direction, and each through hole is in communication with the bore 21 a of the dilator tube 21. In addition, since the material of the dilator tube 21 is the same as that of the above-mentioned 1st Embodiment, the description is abbreviate | omitted.

  Near the distal end (tip) of the dilator tube 21, a contrast marker 23 is provided. In this embodiment, the contrast marker 23 is an annular ring member and is an outer surface of the dilator tube 21 and is extrapolated to a position on the proximal end side by a predetermined dimension from the distal end of the dilator tube 21 It has been fitted. The position of the contrast marker 23 is detected by X-ray fluoroscopy to be a marker in the body, and, for example, a metal material such as gold, platinum or tungsten, or an X-ray such as a polymer in which barium sulfate or bismuth oxide is blended. It is formed of an impermeable material. In the present embodiment, a platinum-iridium alloy (PtIr) is used.

  A rough surface 23 a is provided on the outer surface of the contrast marker 23 by forming fine asperities. The fine asperities constituting the rough surface 23a of the outer surface of the contrast marker 23 can be formed using, for example, a barrel polishing method or a blast processing method, as in the first embodiment described above, and chemical chemistry such as etching is possible. It may be formed by irregularly scraping the surface by a surface treatment method, or by using a sandpaper, a metal brush or the like.

  In the present embodiment, the outer diameter of the contrast marker 23 is set to 2.53 mm, and the inner diameter is set to 2.48 mm. In the present embodiment, the axial length of the contrast marker 23 is set to 1.50 mm.

  The surface roughness of the rough surface 23a of the contrast marker 23 can be set in the range of 0.5 to 5.0 μm in terms of arithmetic mean roughness (Ra), and in the present embodiment, it is in terms of arithmetic mean roughness (Ra) The ring member before surface processing of 0.1 μm is barrel-processed, and the surface roughness is 1.8 μm in arithmetic average roughness (Ra). The surface roughness of the rough surface 23a of the contrast marker 23 is set to such an extent that the ultrasound visibility can be improved without adversely affecting the insertability into the body tissue (puncture hole).

  The position where the contrast marker 23 having the rough surface 23a (i.e., the rough surface 23a) is provided on the outer surface is a tapered portion 21b and a portion in the vicinity of the distal end side (distal end side) of the straight body continuous with the tapered portion 21b. The extension portion is not particularly limited as long as it is an expanded portion including (proximal straight body portion) 21d, but in the present embodiment, the distal end of the contrast marker 23 is at the boundary between the tapered portion 21b and the proximal straight body portion 21d. It arranges so that it may correspond substantially.

  For example, the diameter of the contrast marker 23 is reduced by caulking or the like in a state where the distal end side of the dilator tube 21 is inserted (pressed) and located at a predetermined position from the distal end of the dilator tube 21 It can be attached to the dilator tube 21 by pressing deformation. This mounting operation can be performed in a state where the tip of the dilator tube 21 is heated and softened.

  In addition, molding of the taper part 21b of the front-end | tip of the dilator tube 21 and the front-end straight body part 21c can be performed using the metal mold | die similar to the metal mold | die 15 of 1st Embodiment mentioned above.

  As the contrast marker 23, when the outer surface unprocessed one (arithmetic mean surface roughness (Ra) 0.1 μm) is used (when the rough surface 13a is not provided), the outer surface is roughened by barrel processing When the ultrasonic image is compared with the case where the surface 23 a is provided (arithmetic mean surface roughness (Ra) 1.8 μm), the visibility is apparent in the case where the rough surface 23 a is provided. Improved.

  According to the second embodiment described above, the rough surface 23a is provided on the outer surface of the contrast marker 23 externally fitted to the dilator tube 21, and the surface roughness of the fine irregularities constituting the rough surface 23a is optimized as described above. Therefore, ultrasonic visibility can be improved while minimizing inhibition of the insertability of the dilator tube 21 into body tissue.

Third Embodiment
Next, a third embodiment of the present invention will be described with reference to FIGS. The ultrasonic endoscope dilator 3 according to the third embodiment of the present invention is a dilator comprising an elongated tube inserted into a patient's body (a lumen) through a treatment instrument guide tube of an endoscope (not shown). It is connected to the proximal end side of the tube 31 and the dilator tube 31, and is roughly provided with the operation part 32 for an operator to hold when operating the dilator tube 31 in the body from the outside of the body.

  The dilator tube 31 is made of a flexible elongated tube and has a lumen through which a guide wire (not shown) is inserted. The diameter (diameter) of the inner diameter of the dilator tube 31 is not particularly limited as long as it is equal to or larger than the outer diameter of the guide wire inserted into the inner diameter, but at least at the tip (distal end) of the dilator tube 31 From the viewpoint of improving the insertability into the puncture hole, it is preferable to make the diameter slightly larger than the outer diameter of the guide wire used. In the present embodiment, the diameter (diameter) of the inner cavity 31a of the dilator tube 31 is set to 0.93 mm in the vicinity of the distal end (where the thermoforming is applied), and in the portion on the proximal end side It is set to 1.10 mm.

  The outer diameter of the dilator tube 31 is set to a diameter that can expand the puncture hole to a desired diameter, and can be set, for example, in the range of 1.20 to 3.50 mm. In the present embodiment, the outer diameter of the dilator tube 31 is set to 2.45 mm (7 Fr). The length of the dilator tube 31 can be set, for example, in the range of 1500 to 2500 mm, and is set to 1800 mm in this embodiment.

  The distal end portion (distal end portion) of the dilator tube 31 is provided with a tapered portion 31b which is formed to be tapered toward the distal end (distal end). The tapered portion 31b gradually expands the punctured hole formed in the body tissue, and contributes to the expansion of the punctured hole in the vicinity of the distal end side (distal end side) of the straight body continuing to the tapered portion 31b. To smoothly guide the portion) into the puncture hole. Note that the tapered portion 31b and a portion (proximal end straight body portion) 31d in the vicinity of the distal end side (distal end side) of the straight body portion continuous with the tapered portion 31b expand the puncture hole formed in the body tissue It becomes a part.

  Although not particularly limited, in the present embodiment, the distal end portion of the distal end tapered portion 31 b is provided with a distal end straight body portion 31 c of a straight cylinder whose diameter does not change. The dimension (length) of the tapered portion 31b can be set, for example, in the range of 5.0 to 20.0 mm, and in the present embodiment, it is set to 11.5 mm. The dimension (length) of the front end straight body 31c can be set, for example, in the range of 1.00 to 3.00 mm.

  At the proximal end of the dilator tube 31, a gripping member constituting the operation unit 32 is attached. The holding member has a through hole (not shown) penetrating in the axial direction, and the through hole is in communication with the inner cavity of the dilator tube 31. In addition, since the material of the dilator tube 31 is the same as that of the above-mentioned 1st Embodiment, the description is abbreviate | omitted.

  Near the distal end (tip) of the dilator tube 31, a contrast marker (not shown) is provided. The contrast marker is a marker in the body whose position is detected by X-ray fluoroscopy and becomes a marker in the body, for example, a metal material such as gold, platinum, tungsten or the like, or an X-ray radiation such as a polymer blended with barium sulfate or bismuth oxide. It is formed of a permeable material. In the present embodiment, a platinum-iridium alloy (PtIr) is used.

  A rough surface 33 a is provided on the outer surface of the tapered portion 31 b of the dilator tube 31 by forming fine asperities. The method of forming the fine asperities constituting the rough surface 33a of the outer surface of the tapered portion 31b is not particularly limited. For example, using the tip molding die 35 as shown in FIG. When molding, it can be done simultaneously. That is, from the one end portion side (right side in FIG. 14), the tip molding die 35 has a lumen 35a set to have substantially the same diameter as the outer diameter of the straight body tube 34 serving as a base material of the dilator tube 31. And the other end (from the left side in FIG. 14) to a diameter smaller than that of the tube 34 (approximately the same diameter as the tip outer diameter of the tapered portion 31 b to be formed (the outer diameter of the tip straight trunk portion 31 c)) It has a cavity 35 c and a lumen 35 b which tapers between them. Fine asperities are formed on the inner surface of the tapered lumen 35b. Although not shown, a heater is provided inside the mold 35.

  In molding the tip, a lot bar 36 is inserted into the lumen of the tube 34 as shown in FIG. The lot bar 36 is for suppressing the collapse of the lumen when the tip of the tube 34 is molded by the mold 35. The lot bar 36 is an elongated cylindrical member made of metal or the like, and the outer diameter thereof is set to be substantially the same as the diameter (diameter) of the inner cavity 31 a to be secured in the formed dilator tube 31. In this embodiment, it is 0.93 mm.

  When the tip of the tube 34 into which the lot bar 36 is inserted is inserted into the inner cavity 35a of the mold 35, the tip of the tube 34 is heated by the heat of the heater of the mold 35 and softened. It enters along the shape of the cavity 35b. By pushing the tube 34 by a preset amount of pushing (for example, 7.5 mm), the tip of the tube 34 is formed into a tapered shape by the lumen 35b, and at the same time, the minute portion of the lumen 35b is formed in this tapered portion. The unevenness is transferred, and the tip reaches the inside of the lumen 35c to form a tip straight barrel. In this state, by pulling out the tube 34 from the mold 35 or by opening the mold 35, the dilator tube 31 having a tapered portion 31b having a rough surface 33a at its tip and a tip straight barrel 31c. Is manufactured.

  Arithmetic mean surface roughness of the tapered portion (the tapered portion is formed by using a die having no fine asperities on the inner surface of the tapered inner cavity 35b as the tip end molding die 35 and forming no rough surface in the tapered portion Ra) 0.3 μm) and the dilator tube 31 (the arithmetic average surface roughness (Ra) of the tapered portion 31 b is 3.1 μm) in which the rough surface 33 a is provided on the outer surface of the tapered portion 31 b When the ultrasonic image was compared by the case where it used, the visibility improved more in the thing which provided the rough surface 33a.

  In addition, as a formation method of fine unevenness which constitutes rough surface 33a in taper part 31b of dilator tube 31, after forming a taper part, it may not be limited to the above-mentioned method, and it may form by blast processing method etc.

  In the third embodiment described above, the rough surface 33a is provided on the entire outer surface of the tapered portion 31b, but as the position where the rough surface 33a is provided, the tapered portion 31b and a straight body portion continuous with the tapered portion 31b It is not particularly limited as long as it is an expanded portion including a portion (proximal straight body portion) 31 d in the vicinity of the distal side (distal end side) of In addition, the rough surface 33a may be provided on the whole of the expanded portion, or may be provided on only a part.

  According to the third embodiment described above, since the rough surface 33a is provided on the outer surface of the tapered portion 31b of the dilator tube 31 and the surface roughness of the fine irregularities constituting the rough surface 33a is optimized within the above range, the dilator tube The ultrasound visibility can be improved while minimizing the inhibition of the insertion into the living tissue of 31.

  The embodiments described above are described to facilitate the understanding of the present invention, and are not described to limit the present invention. Therefore, each element disclosed in the embodiment described above is intended to include all design changes and equivalents that fall within the technical scope of the present invention.

  For example, although the first to third embodiments described above relate to an ultrasonic endoscope dilator comprising approximately only the dilator tube and the operation unit, the ultrasonic endoscope dilator according to the present invention The invention is not limited thereto, and may have members other than the dilator tube and the operation unit, and may not have the operation unit. In addition, the dilator for an ultrasonic endoscope of the present invention may be configured to perform functions other than the function of expanding the puncture holes provided in various organs and the constrictions of various body lumens, etc. For example, , And may be configured to function as a stent delivery catheter.

1, 2, 3 Dilator 11, 21, 31 Dilator tube 11b, 21b, 31b Tapered portion 13, 23 Contrast marker 13a, 23a, 33a Rough surface 15, 35 Tip mold

Claims (2)

Ultrasonic wave comprising a flexible tube having a tapered portion at its distal end portion, an expanded portion having a straight body portion near the proximal end side of the tapered portion, and a lumen into which a guide wire is slidably inserted It is a dilator for endoscopes.
Roughening the whole or part of the extension ,
An annular contrast marker externally or internally fitted to the extension;
The dilator for an ultrasonic endoscope , wherein the rough surface is provided on the outer surface of the contrast marker . The dilator for an ultrasonic endoscope according to claim 1, wherein the rough surface is set in the range of 0.5 to 5.0 m in arithmetic average surface roughness (Ra).

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