| 摘要 |
<p>A surgical extractor (10) for removing calculi, such as kidney stones and gall stones, from the body. The extractor includes a handle (11) at a proximal end (12) of the extractor with a slider (14) for operation by a physician. At the distal end (16) the extractor includes a plurality of pairs of wires (15) with portions of each pair being formed along the turn of a helix. When a retaining sheath (17) is retracted, the wires, formed of a shape memory material such as stainless steel, expand such that each pair of wires closely assumes a path along a helical turn with individual wires remaining closely adjacent. This use of plural wires for each strand multiples the number of contacts with entrapped calculi and can be provided without any deleterious effect on the reliability or size of the extractor.</p> |
