TECHNICAL FIELD

The present invention relates to a tunnel device.

BACKGROUND ART

For the purpose of implanting an artificial blood vessel for peripheral vascular reconstruction or dialysis, tunnel devices each forming a subcutaneous tunnel and implanting an artificial blood vessel subcutaneously have been used. For example, a tunnel device including a handle to be held, a shaft to be connected to the handle, and a chip portion to be attached to a tip of the shaft is disclosed in Patent Literature (hereinafter, referred to as “PTL”) 1.

The tunnel device of PTL 1 is configured such that the shaft is detachably connected with respect to the handle. The connection of the shaft with respect to the handle is made by screwing a female screw portion formed on an inner peripheral surface of an end portion of the shaft with an outer periphery of a male screw portion provided so as to protrude from one end of the handle.

CITATION LIST

Patent Literature

PTL 1

U.S. Pat. No. 5,306,240

SUMMARY OF INVENTION

Technical Problem

However, when the tunnel device is conducted subcutaneously by operation for forming a subcutaneous tunnel, for example, a tip of the tunnel device is pushed by a physical force and moved forward subcutaneously, and thus, the tunnel device forms a passage for the shaft as a subcutaneous tunnel. When a subcutaneous tunnel is formed by such a tunnel device, the tunnel device touches a body fluid, and/or subcutaneous tissue scrapped off by friction with the tunnel device adheres to the tunnel device in some cases. In a case where a body fluid and/or subcutaneous tissue attaches to the tunnel device, the body fluid and/or subcutaneous tissue enters between the shaft and the handle in some cases. In the tunnel device described in PTL 1, a structure is adopted in which the tunnel device includes a shaft and a handle serving as a base portion to be connected to the shaft, and a female screw portion formed on an inner peripheral surface of an end portion of the shaft is screwed with an outer periphery of a male screw portion provided so as to protrude from one end of the handle. For this reason, the body fluid and/or a cell that has entered from a gap between the shaft and the handle during operation enters between the male screw portion and the female screw portion in some cases. Although tunnel devices are supposed to be disassembled and washed for each use, it is difficult to wash a groove portion of the female screw portion and/or male screw portion. More specifically, adhesion of a body fluid and/or the like to a place where cleaning is difficult, such as the female screw portion and/or male screw portion, results in a hygienic problem.

An object of the present invention is thus to provide a tunnel device which is safe and good in a hygienic aspect, such as cleaning.

Solution to Problem

A tunnel device of the present invention includes: a base portion; a shaft to be connected to the base portion at one end of the shaft; and a tip portion to be connected to another end of the shaft, in which the base portion is provided with a shaft connection portion to which the one end of the shaft is connected, and the shaft is provided with a shaft-side screw portion at the one end of the shaft, in which the shaft connection portion includes: a shaft housing portion having an inner diameter substantially same as an outer diameter of the one end of the shaft; and a base-portion-side screw portion provided on a further inner side relative to the shaft housing portion, in which the base portion and the shaft are fixed to each other by screwing between the shaft-side screw portion and the base-portion-side screw portion.

Advantageous Effects of Invention

According to the tunnel device of the present invention, a tunnel device which is good in a hygienic aspect, such as cleaning, can be used in a hygienically safe manner.

