PROBLEM TO BE SOLVED: To provide a retractor which is an operative field expanding instrument for intracardiac surgery to be used in a cardiac surgery performed endoscopically or under a surgery support robot, has such a structure that an optimum space for securing a visual field inside the heart can be maintained, has an automatic expansion type structure that can be deformed into a narrow shape when the retractor is to be inserted from a small port and can be returned to an original structure automatically after entering the body, and is formed of a soft material not damaging the heart.SOLUTION: The retractor is turned to the structure of indwelling a flexible tubular body around which a fully flexible tube 1 is spirally wound inside the heart. The retractor is made of a material such as Teflon(R), polyethylene, polypropylene, nylon, polyurethane or vinyl chloride. Thus, the surgery is quickly, accurately and easily performed, and the cardiac surgery can be safely performed even to an elderly person or a patient with highly severe disease.COPYRIGHT: (C)2013,JPO&INPIT【課題】内視鏡下や手術支援ロボット下での心臓手術に用いる、心内手術用術野展開器具であり、心臓内で視野確保のための至適な空間を維持できる構造であり、また、リトラクターを小さいポートから挿入しようとすれば、細い形状に変形可能でかつ又体内に入った後自動的に、元の構造にもどる自動拡張型の構造でり、かつ心臓を傷つけない柔らかい素材で作られたリトラクターを提供する。【解決手段】可塑性に富んだチューブ1を螺旋状に巻いた柔軟な管状体を心臓内に留置する構造とされていることを特徴とする。素材は、例えばテフロン(登録商標)、ポリエチレン、ポリプロピレン、ナイロン、ポリウレタン、塩化ビニールなどで制作することで手術が迅速、正確、かつ容易となり、高齢者や高度重症患者に対しても安全に心臓手術が可能となる。【選択図】図3