PROBLEM TO BE SOLVED: To provide a body organ expansion instrument using a self-expansion stent, transmitting little twisting force applied to the proximal end to a stent storage cylindrical member, and applying little twisting to a traction wire for the traction of the cylindrical member.SOLUTION: The body organ expansion instrument 1 comprises a distal end tube 2, a proximal end tube 4, a sliding tube 7 which is close to the proximal end of the stent storage cylindrical member 5 and which is not fixed to the cylindrical member 5, a fixed tube 8 to which the distal end tube 2 and the proximal end tube 4 are fixed and in which the sliding tube 7 can be stored, and the traction wire 6 for moving the cylindrical member 5 to the proximal end side. The sliding tube 7 is movable to the proximal end side by the traction of the traction wire 6 and has a ring-shaped member 75 which is stored inside, to which the traction wire is fixed, and which is movable together with the sliding tube.COPYRIGHT: (C)2009,JPO&INPIT【課題】自己拡張型ステントを用いる生体器官拡張器具であって、基端部において付与した捻り力のステント収納用筒状部材への伝達、この筒状部材を牽引するための牽引ワイヤに捻れを与えることが少ない生体器官拡張器具を提供する。【解決手段】 生体器官拡張器具1は、先端側チューブ2と、基端側チューブ4と、ステント収納用筒状部材5の基端に近接し、かつ筒状部材5に固定されていないスライドチューブ7と、先端側チューブ2と基端側チューブ4が固定され、かつスライドチューブ7を収納可能な固定チューブ8と、筒状部材5を基端側に移動させるための牽引ワイヤ6を備える。スライドチューブ7は、牽引ワイヤ6の牽引により基端側に移動可能であり、内部に収納され、牽引ワイヤが固定されかつスライドチューブとともに移動可能なリング状部材75を備える。【選択図】 図3