JPH0213006Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an expansion tube suitably used for diagnosis and treatment of internal organs, particularly for expanding a fistula to a desired internal diameter.

A fistula is formed, for example, in the case of biliary stricture or biliary tract cancer, to form percutaneous transhepatic biliary drainage and to allow bile to drain out of the duodenum.

As shown in Fig. 1, the conventional method for forming a fistula is to first form a narrow passageway from the skin to a desired site in the body using a puncture needle, and then insert a thin tube into which a guide wire 1 is inserted into the core. and wait for the fistula to form over time. Next, when attempting to enlarge the fistula, a guide wire is inserted into the thin tube, the thin tube is removed, a thick tube 2 for enlargement of the fistula is inserted, and the fistula is pushed in. The thick tube 2 has an outer diameter corresponding to the desired diameter of the fistula and has a conical tapered tube at its tip, which pushes and expands the inner wall of the fistula. Since the fistula cannot be enlarged all at once, prepare several thick tubes with different outside diameters and enlarge them while replacing them with thicker tubes one by one. At this time, the guide wire is thin and flexible, so the force guiding the thick tube along the fistula is weak, and as a result, the thick tube hits the fistula at an obtuse angle, often damaging the wall of the fistula. Become.

The present invention solves the above-mentioned problems and provides an expansion tube that allows smooth expansion of the fistula, shortens the treatment time, and reduces the burden on the patient.

The gist of this invention is that it consists of a combination of multiple thin-walled elastic tubes that gradually increase in diameter from small to large.
One end of each tube is slidable through an adjacent tube, and the other end is in the configuration of a conically tapered expansion tube.

To explain the expansion tube according to the present invention based on the drawings, _FIG . T ₄ is shown inserted in a sheath shape with T ₁ as the core. For example, from T ₁ to T ₄ , T ₂ is along T ₁ , and T ₃
can be inserted and slid along T ₂ in the same manner. The tip of each tube is a tapered conical tube 3. Further, each tube has a filament 4 attached to its outer periphery along the length direction of the tube. Since the surgery is performed under X-ray fluoroscopy, this filament 4 is used to see through the movement of the tube, and is preferably provided. Note that instead of providing the striations, the entire tube may be made to have an X-ray contrast property, and as the X-ray contrast material, tungsten metal and its compounds, barium compounds, etc. can be used. FIG. 3 shows, as an example, a sectional view of the tip end when the tube T ₃ is fitted onto the tube T ₂ .

To describe the mode of expanding a fistula using the expansion tube according to the present invention, a guide wire is inserted into the lumen of the thin tube placed in the foraminal canal, the thin tube is removed,
A tube T ₁ having an outer diameter equal to or smaller than that of the tubule is fitted along the guide wire, and the tube T ₁ is placed in the same position where the tubule was placed. Next, T ₂ is drawn out along the outside of T ₁ from outside the body, and T ₂ is inserted into the fistula so as to widen the space between T ₁ and the fistula that is in close contact with it. Then similarly along tube T ₂
Push T ₃ forward, and perform the following operations in the same way depending on the situation, and finally find the diameter that corresponds to the desired diameter of the hole.
Insert and expand T _o . In this way, since the tube is inserted and expanded along the fistula, the expansion tube hits the inner wall of the fistula at an obtuse angle and can be expanded without damaging the fistula.

In this invention, the pipes with larger diameters are successively fitted over the pipes with smaller diameters, and the holes are expanded one after another.In order to expand smoothly, it is necessary to adjust the diameter ratio of the next pipe directly above. (expansion ratio) is required not to be larger than necessary, the wall thickness of each tube is also preferably not too thick, and the clearance between the inner tube and the outer tube is required to ensure the slidability of the tube. It is preferable to have as few as possible. The clearance ranges from 0.05mm to 0.2mm on one side, so the difference between the inner diameter of the outer tube and the outer diameter of the inner tube is 0.1mm to 0.4mm.
The thickness is preferably about 0.3 mm. Since the clearance is small as mentioned above, fluorine resin or polyethylene, which has a small coefficient of friction and good sliding properties, is suitable as the material for the pipe. In addition, the wall thickness of the tube is 0.2 mm to 0.5
Approximately mm is preferable.

According to the present invention, as described above, the expansion of the fistula is smoothly performed at each stage with safe guidance.
Therefore, the time required to form the final dilated fistula can be shortened, and the procedure is much safer and less stressful for the patient.

Although the expansion tube according to the present invention has been described as an example in which it is used for dilating a fistula, it goes without saying that it is not limited to this and can also be used for other similar purposes. It is.

[Brief explanation of the drawing]

FIG. 1 is a partially omitted sectional view showing a conventional fistula expansion method, FIG. 2 is a partially omitted front view of the expansion tube according to the present invention, and FIG. 3 is a longitudinal sectional view. 1...Guide wire, 2...Thick tube, 3...Conically tapered tube, 4...Striae, _T1 to _T4 ...Tube.

Claims (1)

[Scope of utility model registration request] It consists of a combination of multiple thin-walled elastic tubes that gradually increase in diameter from small to large. One end of each tube can be inserted and slid into an adjacent tube, and the other end is a conical tapered tube. An expansion tube characterized by: