US Patent 7282055 Medical retrieval instrument

A medical retrieval instrument of the present invention includes a plurality of filaments for holding an object and a hollow section through which a first end of each of said plurality of filaments passes. The hollow section comprises a plurality of fixing sections for fixing a second end of each of said plurality of filaments, for example. The hollow section is arranged in a distal end portion of a sheath. The hollow section is inserted into the body cavity by the sheath and then holds an object such as renal calculus or ureteral calculus in the body cavity and retrieves them to outside the body.