PROBLEM TO BE SOLVED: To solve the problem that, when an opening for puncture is widely provided on an outer peripheral surface of an overtube, it is preferable from a viewpoint of ensuring a path for making a puncture needle enter, however, when observing the entry of the puncture needle by an endoscope, there is a case where an inner balloon is not inflated with good visibility.SOLUTION: A guide tube for endoscope comprises: a main body tube having a tip side opening to be inserted into an esophagus between both tips of a through hole for inserting an endoscope, which obliquely intersects with a center axis of the through hole, and a puncture opening provided on a wall surface of the tip side for inserting a puncture needle an outer balloon covering the puncture opening and provided on an outer peripheral surface of the main body tube, which is inflated to an outer peripheral direction of the main body tube and an inner balloon provided to block the puncture opening, which is inflated toward the through hole according to the inflation of the outer balloon. An opening angle around the center axis, of the puncture opening is less than 180 degrees.COPYRIGHT: (C)2015,JPO&INPIT【課題】オーバーチューブの外周面に設ける穿刺用の開口を大きくすると、穿刺針を進入させる経路を確保する観点からは好ましいが、内視鏡により穿刺針の進入を観察する場合に、内バルーンが視認性良く膨張しない場合があった。【解決手段】内視鏡用ガイドチューブは、内視鏡を挿通する貫通孔の両端のうち食道へ挿入される先端側が貫通孔の中心軸に対して斜交する先端側開口と、先端側の壁面に設けられた、穿刺針を通過させる穿刺開口とを有する本体チューブと、穿刺開口を覆って本体チューブの外周面に設けられ、本体チューブの外周方向へ膨張させられる外バルーンと、穿刺開口を閉塞するように設けられ、外バルーンの膨張に合せて貫通孔へ向かって膨張させられる内バルーンとを備え、穿刺開口は、中心軸周りの開口角が180度未満である。【選択図】図3
