Patent ID: 8439851

Claim:
A lumen passability checking device comprising: an expandable and shrinkable outer casing that contains a predetermined fluid, is expanded by a pressure of the contained fluid, and forms an external diameter equal to that of a capsule medical device to be inserted into a body of a subject; and a shape manipulating unit that flows out the fluid contained in the outer casing to shrink-deform the outer casing, the shape manipulating unit comprising: a structure connected to the outer casing in a state of being inserted into an opening part of the outer casing, and having an external diameter smaller than that of the capsule medical device, and a dissoluble unit arranged on an external surface of the structure and dissolved by a predetermined substance in the body of the subject, wherein: the structure is an elastic member arranged in the dissoluble unit and having a through hole through which the fluid is injected, the dissoluble unit closes the opening part of the outer casing, and releases closure of the opening part when the dissoluble unit is dissolved by the substance in the body, along with releasing of the closure of the opening part, the outer casing flows out the fluid via the opening part to be shrink-deformed, and the outer casing is shrink-deformed by flowing out the fluid, while maintaining a state of being integrated with the shape manipulating unit.