The spiral rotating member (130) is disposed on the outer peripheral surface of the main body (131), the cylindrical main body (131) that is inserted through the insertion section (30) and rotates around the longitudinal axis C, and And a fin portion (133) arranged in a spiral around the longitudinal axis C. The spiral rotating member (130) is disposed in at least a part of the spiral rotating member (130) in the longitudinal axis direction of the spiral rotating member (130), and is further clearly imaged by X-rays under X-ray observation. (143) and an unclear region (141) that is unclearly contrasted by X-rays are arranged so as to be identified in the circumferential direction of the spiral rotation member 130, and an X-ray blocking section (135) that blocks X-rays It has further.螺旋回転部材（１３０）は、挿入部（３０）が挿通し、長手軸Ｃの軸周りに回転する円筒状の本体部（１３１）と、本体部（１３１）の外周面に配設され、且つ長手軸Ｃの軸周りに螺旋状に配設されるフィン部（１３３）とを有している。螺旋回転部材（１３０）は、螺旋回転部材（１３０）の長手軸方向において螺旋回転部材（１３０）の少なくとも一部に配設され、さらにＸ線観察下においてＸ線によって明瞭に造影される明瞭領域（１４３）とＸ線によって不明瞭に造影される不明瞭領域（１４１）とが螺旋回転部材１３０の周方向において識別されるように配設され、Ｘ線を遮断するＸ線遮断部（１３５）をさらに有している。
