JP2010220744A - Medical dilator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a medical dilator, simplifying operation to shorten the operation time, and minimizing a change in insertion resistance value in dilating tissue. <P>SOLUTION: This medical dilator includes: a small-diameter dilating member having an inner cavity allowing a guide wire to penetrate therethrough and a first tapered part tapered toward the tip; and a large-diameter dilating member having an inner cavity where the small-diameter dilating member is removably assembled, and a second tapered part tapered toward the tip. The ratio (A):(B) of the first tapered part angle (A) of the small-diameter dilating member and the second tapered part angle (B) of the large-diameter dilating member is from 1:1.3 to 1:1.7 both inclusive. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a medical dilator.

In recent years, for patients who cannot take nutrients or chemicals orally orally, a gastrostomy is constructed in the patient's abdomen by percutaneous endoscopic gastrostomy (hereinafter abbreviated as PEG). However, enteral nutrition management in which nutrition or a drug solution is administered from the gastrostoma has been frequently performed.
PEG is a surgical method for constructing a gastrostomy by opening a fistula in the abdominal wall and stomach wall, inserting a catheter comprising an indwelling member, a tube member and an external fixation member into the fistula, and placing the catheter in the abdomen. It is. The steps include inserting an endoscope into the stomach, (1) fixing the abdominal wall and stomach wall, (2) piercing the abdominal wall and stomach wall with a puncture needle, and forming a through hole, (3) penetration A step of inserting a guide wire into the hole; (4) a step of inserting a fistula construction dilator along the guide wire into the through hole and expanding the diameter of the through hole to form a fistula; and (5) a guide wire. And (6) a step of removing the guide wire. In the present invention, a through hole refers to a hole before or during expansion by a medical dilator, while a fistula refers to a hole after being expanded by a medical dilator.

(4) The process of inserting a medical dilator into a through hole along the guide wire and expanding the diameter of the through hole to form a fistula can be expanded as easily as possible and has a good insertion property. A vessel is desired.
Conventionally, various medical dilators for expanding tissue have been disclosed. For example, Patent Literature 1 discloses a medical dilator in which a small diameter expansion member is inserted under a guide wire, a medium diameter dilator is subsequently inserted, and then a large diameter expansion member is sequentially inserted. Patent Document 2 discloses a medical dilator comprising a combination of a plurality of thin elastic tubes that gradually increase from a small diameter to a large diameter.

JP-A-2-111336

Japanese Utility Model Publication 59-143439

However, the above-described medical dilator has a problem that it is necessary to sequentially insert medical dilators having different outer diameters, so that the operation becomes complicated and the operation time becomes long.
In addition, in a medical dilator composed of a combination of a plurality of dilators having different outer diameters, the insertion resistance may change, so that it may be difficult to insert the dilator smoothly.
Accordingly, an object of the present invention is to provide a medical dilator that is easy to operate, shortens the operation time, and has a small change in insertion resistance during tissue expansion.

Such an object is achieved by the present invention described in (1) and (2) below.
(1) a small-diameter expansion member having a lumen through which a guide wire can be inserted and having a first tapered portion that is tapered toward the tip;
A large-diameter expansion member having a lumen into which the small-diameter expansion member is removably incorporated, and having a second tapered portion that is tapered toward the tip;
A medical dilator comprising:
The ratio (A) :( B) of the first taper portion angle (A) of the small diameter expansion member and the second taper portion angle (B) of the large diameter expansion member is 1: 1.3 or more, 1: A medical dilator characterized by being 1.7 or less.
(2) The medical dilator according to (1), which is used for gastrostomy.

  According to the present invention, it is possible to provide a medical dilator that is easy to operate, shortens the operation time, and has a small change in insertion resistance value during tissue expansion.

The front view before the assembly of the small diameter expansion member and large diameter expansion member in one Example of the medical dilator of this invention is shown. The front view after the assembly of both the expansion members in one Example of the medical dilator of this invention is shown. FIG. 3 shows a cross-sectional view of FIG. 2. The thin diameter expansion member of the medical dilator of this invention is shown. Shows a cross-sectional view of FIG. The large diameter expansion member of the medical dilator of this invention is shown. 6 shows a cross-sectional view of FIG. The insertion resistance curve in the Example and comparative example of the medical dilator of this invention is shown.

The medical dilator of the present invention will be described with reference to FIG. FIG. 1 shows a front view of a medical dilator 1 according to an embodiment of the present invention before the small-diameter expansion member 2 and the large-diameter expansion member 3 are combined. The small-diameter expansion member 2 includes a cylindrical first body portion 21 that serves as a dilator main body, a first tapered portion 22 that tapers toward the tip, and a first end portion attached to the rear end of the first body portion 21. One hub 26 is provided. The large-diameter expansion member 3 includes a cylindrical second body portion 31 that serves as a dilator main body, a second tapered portion 32 that tapers toward the tip, and a second end portion attached to the rear end of the second body portion 31. Two hubs 36 are provided.
By inserting the tapered first tapered portion 22 of the small-diameter expansion member 2 from the second hub 36 attached to the rear end of the large-diameter expansion member 3 into the lumen of the second body portion 31, The expansion member of the book is integrated to form the medical dilator of the present invention.

The medical dilator of the present invention will be described with reference to FIGS. As described with reference to FIG. 1, the medical dilator 1 is obtained by combining the small diameter expansion member 2 and the large diameter expansion member 3 as described above. 2 shows a front view of the medical dilator 1 and FIG. 3 shows a cross-sectional view of FIG.
The small-diameter expansion member 2 has a hollow first hollow 25 extending in the longitudinal direction, and a guide wire (not shown) can be inserted therethrough.
The large-diameter expansion member 3 also has a hollow second cavity 35 extending in the longitudinal direction, and the small-diameter expansion member 2 can be removably incorporated therein.

The medical dilator 1 includes a first tapered portion 22 of the small-diameter expanding member 2 and then a first body portion 21 from the tip, and an inner diameter that is substantially the same as the outer diameter of the first body portion 21. The second taper portion 32 of the large-diameter expansion member 3 having the following, and then the second body portion 31.
The rear end of the medical dilator 1 is configured such that the first hub 26 of the small-diameter expansion member 2 is fitted into the lumen of the second hub 36 of the large-diameter expansion member 3. It becomes a generalized dilator.

Since tissue expansion is inserted to the vicinity of the distal end side of the second body part 31, when used for surgery, the resistance to which the first tapered part 22 is inserted, and then the first body part 21 is inserted. The operator feels the resistance, the resistance at which the second tapered portion 32 is inserted, and finally the resistance at which the second body portion 31 is inserted.
Actually, the resistance at which the first body portion 21 is inserted is substantially equal to or less than the resistance at which the first tapered portion 22 is inserted, and the resistance at which the second body portion 31 is inserted. Is approximately equal to or less than the resistance into which the second taper portion 32 is inserted. Therefore, in order to obtain a dilator having good insertability, the resistance into which the first taper portion 22 is inserted, It is necessary to optimize two resistances of the resistance into which the two taper portions 32 are inserted.

As shown in FIG. 3, the small-diameter expansion member projecting portion 12 refers to the distal end portion of the small-diameter expansion member 2 projecting from the distal end portion of the large-diameter expansion member 3 in the medical dilator 1. That is, it refers to the total of all the first tapered portions 22 of the small diameter expansion member 2 and a part of the front end portion of the first body portion 21 protruding from the front end portion of the large diameter expansion member 3.
Since the inner diameter of the second taper portion 32 of the large-diameter expansion member 3 is configured to be substantially the same as the outer diameter of the first body portion 21 of the small-diameter expansion member 2, the small-diameter expansion member protrusion 12. Is the rear end of the first tapered portion 22 of the small diameter expansion member 2 in the shortest case.

The small-diameter expansion member 2 is preferably made of a softer material than the large-diameter expansion member 3, so that when the guide wire is inserted, the small-diameter expansion member protrusion 12 is guided in the direction of the guide wire. Therefore, it can be safely expanded without damaging the opposing walls of the expanded tissue and organ.
Furthermore, the followability to a guide wire can be improved by lengthening the length of the small diameter expansion member protrusion part 12. However, if the length is too long, there is a risk of damaging the opposing wall of the organ due to the length of insertion into the tissue or organ being increased before the second body portion 31 of the large-diameter expansion member 3 is inserted. It is necessary to make it an appropriate length depending on the situation.

FIG. 4 shows the small diameter expansion member 2 of the present invention, and FIG. 5 shows a cross-sectional view of FIG.
The first body portion 21 has a hollow lumen 25 and has a structure in which a guide wire can be inserted.
The outer diameter of the first body portion 21 is not particularly limited, but is not particularly limited as long as the guide wire can be inserted into the small-diameter expansion member 2, but is preferably 1.3 to 6 mm, particularly preferably. Is 1.4 to 1.8.

  The first taper portion 22 has a conical shape whose outer diameter decreases toward the tip. The inner diameter of the tip of the first taper portion 22 is not particularly limited as long as the small diameter expansion member 2 is slidable along the guide wire, and is appropriately selected depending on the outer diameter of the guide wire. . And the clearance between the front-end | tip of the 1st taper part 22 and a guide wire, ie, the difference of the internal diameter of this front-end | tip, and the outer diameter of a guide wire is 0.01-0.2 mm, Preferably it is 0.02-0. 0.09 mm. As the guide wire, for example, when a 0.035 inch guide wire having an outer diameter of 0.89 mm is used, the inner diameter of the tip of the first tapered portion 22 is preferably 0.9 to 1.1 mm, particularly Preferably it is 0.92-0.98 mm. Further, the closer the outer diameter of the tip 16 of the first taper portion 22 is to the inner diameter of the tip of the first taper portion 22, the less resistance at the tip when expanding the through-hole with the medical dilator. To preferred.

  The first taper angle (A) 23 becomes smaller as the first taper portion 22 becomes an acute angle. In order to improve the insertability, the first taper angle (A) is preferably 1 degree or more and 8 degrees or less, and more preferably 1 degree or more and 4 degrees or less. The first taper portion length 24 becomes longer as the first taper portion 22 has an acute angle. If the distance to the opposing wall of the tissue or organ is limited, it may be necessary to shorten it as much as possible. In that case, the first taper angle (A) 23 is most preferably 3 degrees or more and 4 degrees or less because the insertion resistance is good.

The second body portion 31 is hollow and has a structure in which the small-diameter expansion member 2 can be inserted.
Since the outer diameter of the second body portion 31 is approximately the same as the inner diameter of the fistula to be constructed, it is appropriately selected depending on the outer diameter of the tube member of the catheter to be placed. That is, the outer diameter of the second body portion 31 is substantially the same as the outer diameter of the tube member or 0.5 to 3.0 mm larger than the outer diameter of the tube member, preferably 1.0 to 2.0 mm. large. In order to reduce the burden on the patient, the outer diameter of the second body 31 is preferably slightly larger than the outer diameter of the tube member of the catheter. 12 mm is preferable, More preferably, it is 8-10 mm.

The inner diameter of the second body part 31 is not particularly limited as long as the first body part 21 can be inserted, but is preferably 4 to 10 mm, particularly preferably 5 to 7 mm.
The second tapered portion 32 has a conical shape whose outer diameter decreases toward the tip. The inner diameter of the tip of the second tapered portion 32 is substantially the same as the outer diameter of the first body portion 21 and is appropriately selected depending on the size of the first body portion 21. Also, the outer diameter of the tip of the second taper portion 32 is closer to the inner diameter of the tip of the second taper portion 32, and the resistance at the tip is less when the medical expander expands the through hole. It is preferable that the inner diameter is the same as the inner diameter at the tip of the second tapered portion 32.

  The second taper angle (B) 33 becomes smaller as the second taper portion 32 becomes an acute angle. In order to improve the insertability, the second taper angle (B) is preferably 1 degree or more and 8 degrees or less, and more preferably 1 degree or more and 6 degrees or less. The second taper portion length 34 becomes longer as the second taper portion 32 becomes sharper. If the distance to the opposing wall of the tissue or organ is limited, it may be necessary to shorten it as much as possible. In that case, the second taper angle (B) 33 is most preferably 5 degrees or more and 6 degrees or less because the insertion resistance is good.

The total length of the second torso 31 is at least the total length of the portion gripped by the operator, the thickness of the abdominal wall and the thickness of the stomach wall, preferably 50 to 300 mm, particularly preferably 180 to. 230 mm.
The scale 37 is preferably attached to the second body part 31. That is, the portion to which the scale 37 is attached is preferably a portion excluding the second tapered portion. By attaching the scale 37, the necessary length of the catheter to be placed can be confirmed simultaneously with the tissue expansion.

  In the medical dilator 1 of the present invention, the relationship between the first taper angle (A) 23 and the second taper angle (B) 33 at which a length with good insertability can be obtained is as follows. The ratio (A) :( B) of the second taper portion angle (B) 33 is 1: 1.3 or more and 1: 1.7 or less. By setting this ratio, the operator feels almost no resistance change at the time of insertion and can insert smoothly, so that the operation is simple and the operation time can be shortened.

  The materials of the second body part 31 and the second taper part 32 of the large-diameter expansion member 3 and the first body part 21 and the first taper part 22 of the small-diameter expansion member 2 are not particularly limited. It is preferably a material that is excellent in compatibility, does not crush or buckle when expanded, and is slippery. For example, polytetrafluoroethylene resin (PTFE resin), polyvinylidene difluoride resin (PVdF resin) And fluororesins such as tetrafluoroethylene / hexafluoropropylene copolymer resin (FEP resin). Also, vinyl chloride resin, polyethylene resin, nylon resin, etc. can be used by carrying out a surface hydrophilic treatment or the like when it is thick enough to obtain sufficient strength and is difficult to slip. The second body portion 31 and the second tapered portion 32 may be integrally formed, or may be formed by bonding a cylindrical part and a conical part. In addition, the first body portion 21 and the first tapered portion 22 may be integrally formed, or may be formed by bonding a cylindrical part and a conical part.

The second hub 36 is attached to the end of the second body portion 31, and the first hub 26 is attached to the end of the first body portion 21, and the second hub 36 and the first hub are attached. 26, when the through hole was expanded, the first hub 26 was fitted into the second hub 36, so that the large diameter expansion member 3 was inserted into the large diameter expansion member. This is a member for fixing the small diameter expansion member 2. The attachment of the second hub 36 and the first hub 26 is arbitrary, but when the through-hole is expanded, the large-diameter expansion member 3 and the small-diameter expansion member 2 are integrated. Expansion of the through hole from the outer diameter of the small diameter expansion member 2 to the outer diameter of the small diameter expansion member 2, and from the outer diameter of the small diameter expansion member 2 to the large diameter of the large diameter expansion member 3 Since the expansion of the through hole can be performed continuously, it is preferable that the second hub 36 and the first hub 26 are attached in that the operation time can be shortened.
Further, the large diameter expansion member 3 and the small diameter expansion member 2 may be bonded in advance.

Since the second hub 36 and the first hub 26 are attached by press-fitting or adhesive fixing, the workability is good and chemical resistance is required so that cracks do not occur even when a hardener or the like comes into contact. is there. The material of the second hub 36 and the first hub 26 is not particularly limited, but is preferably a hard plastic such as a hard vinyl chloride resin.
In a state where the small diameter expansion member 2 is inserted into the large diameter expansion member 3 and the small diameter expansion member 2 is fixed to the large diameter expansion member 3 with the second hub 36 and the first hub 26, A part of the small diameter expansion member 2 protrudes from the tip of the second tapered portion 32. The length of the narrow-diameter expansion member protrusion 12 is not particularly limited, but is preferably 10 to 100 mm, and particularly preferably 10 to 50 mm. If the length is less than the above range, the flexibility to bend by being guided by the guide wire tends to be poor, and the stomach wall may be stabbed. If the length exceeds the above range, workability is poor. Easy to be. Even if it is less than the above range, there is almost no possibility of damaging the stomach wall if the small-diameter member and the small-diameter member tip are made of a flexible resin.

  The medical dilator of the example and the comparative example is fixed to the universal testing machine, and the resistance value when inserting the medical dilator into the table on which the urethane sponge (thickness of about 15 mm) is fixed is the compression testing mode of the universal testing machine. The insertion resistance at the insertion length was determined. The results are shown in FIG.

<Example>
A small diameter expansion member having a first taper angle (A) of 4 degrees and a large diameter expansion member having a second taper angle (B) of 6 degrees were used. (A) :( B) = 1: 1.5

<Comparative example>
A small diameter expansion member having a first taper angle (A) of 4 degrees and a large diameter expansion member having a second taper angle (B) of 8 degrees were used. (A) :( B) = 1: 2

As can be seen from FIG. 8, an embodiment using the medical dilator of the present invention in which the ratio of the first taper angle (A) 23 and the second taper angle (B) 33 is 1: 1.5. Insertion resistance increased almost in a straight line, and smooth insertion was possible.
On the other hand, in the comparative example in which (A) :( B) is 1: 2, the insertion resistance is not constant, and there is a portion where the insertion resistance value suddenly increases when the insertion length is short. It did not become. From this result, the medical dilator according to the present invention has a small change in insertion resistance value, is easy to operate at the operation site, and can be expected to shorten the operation time.

DESCRIPTION OF SYMBOLS 1 Medical dilator 12 Thin diameter expansion member protrusion part 2 Small diameter expansion member 21 1st trunk | drum 22 First taper part 23 1st taper angle (A)
24 1st taper part length 25 1st lumen | bore 26 1st hub 3 Large diameter expansion member 31 2nd trunk | drum part 32 2nd taper part 33 2nd taper angle (B)
34 Second taper length 35 Second lumen 36 Second hub 37 Scale

Claims (2)

A small-diameter expansion member having a lumen through which a guide wire can be inserted and having a first tapered portion that tapers toward the tip;
A large-diameter expansion member having a lumen into which the small-diameter expansion member is removably incorporated, and having a second tapered portion that is tapered toward the tip;
A medical dilator comprising:
The ratio (A) :( B) of the first taper portion angle (A) of the small diameter expansion member and the second taper portion angle (B) of the large diameter expansion member is 1: 1.3 or more, 1: A medical dilator characterized by being 1.7 or less.   The medical dilator according to claim 1, which is used for gastrostomy.

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