Immobilization and/or retrieval of material from a body can be accomplished, in accordance with the invention, with a device that includes a sheath and a basket. The basket is movable relative to the sheath from a retracted position in which the basket is withdrawn within the sheath and an expanded position in which the basket is extended beyond the distal end of the sheath and open. The basket has a first portion and a second portion with two or more legs extending from the first portion to the second portion. The basket further includes an intermediate portion between the first and second portions in which the legs are spirally arranged, substantially parallel, and non-intersecting. The intermediate portion of the basket is displaced radially outward relative to the first and second portions when the basket is in the expanded position. The basket in the expanded position may be used to immobilize and/or capture material within a body.