PROBLEM TO BE SOLVED: To adjust the obstruction rate of a living body lumen when partially obstructing a living body lumen when the body lumen is partially obstructed, and the adjusted obstruction rate of the living body lumen changes unintentionally. A medical device capable of suppressing the above is provided. A medical device (100) has an elongated inner shaft (110) to be inserted into a blood vessel and an inner cavity in which a first shaft is arranged, and a position of a distal end portion of the inner shaft in a longitudinal direction (X) is fixed. In this state, the deformable expansion portion 122 is provided in a shape expanded in the radial direction R intersecting the long axis direction by contracting in the long axis direction X and a shape contracted in the radial direction extending in the long axis direction. And an outer shaft 120. The expansion part includes a plurality of frames 124b that can expand and contract in the radial direction by expanding and contracting in the long axis direction in the circumferential direction θ of the inner shaft, and the fixing part 124 fixed to the inner wall of the blood vessel in the expanded state, and the long axis. It is provided with another frame 125b that can be expanded and contracted in the radial direction by expanding and contracting in the direction, and an adjusting unit 125 that adjusts the occlusion rate of the blood vessel according to the degree of expansion. [Selection diagram] Fig. 5C【課題】生体管腔を部分閉塞する際に、生体管腔を部分閉塞させる際の生体管腔の閉塞率を調整可能であり、調整した生体管腔の閉塞率が意図せずに変化することを抑制できる医療器具を提供する。【解決手段】医療器具１００は、血管に挿入される長尺な内シャフト１１０と、第１シャフトが配置される内腔が形成され、先端部の内シャフトの長軸方向Ｘにおける位置が固定された状態で長軸方向Ｘに縮むことによって長軸方向と交差する径方向Ｒに拡張した形状と、長軸方向に延びることによって径方向に収縮した形状と、に変形自在な拡張部１２２を備える外シャフト１２０と、を有する。拡張部は、長軸方向に伸縮することによって径方向に拡張収縮自在なフレーム１２４ｂを内シャフトの周方向θに複数備え、拡張した状態で血管の内壁に固定される固定部１２４と、長軸方向に伸縮することによって径方向に拡張収縮自在な他のフレーム１２５ｂを備え、拡張の程度によって血管の閉塞率を調整する調整部１２５と、を備える。【選択図】図５Ｃ
