New monofilament and soft-wire baskets for stone removal

A new-design basket for stone removal uses a standard Teflon catheter with radially positioned holes at its tip to hold either monofilament or soft wire. The strands are positioned to form a basket that will change in both size and shape simply by advancing or retracting these strands. This basket is much safer, can be changed in size during maneuvering , will transmit instruments for stone fragmentation, and can be advanced over a guide wire. It has been effective both in vitro and in the retrieval of biliary and urinary tract stones in 20 patients, several of which could not be retrieved by standard methods.