Answer 6
Lithotripsy is the process of breaking up kidney stones without surgery by using focused shock waves (sound energy). The general idea is that the energy of the shock waves is spread out everywhere except at the stone itself, minimizing the damage to other tissues.

When a single transducer (e.g., underwater spark gap) is used, the reflector is a section of an ellipsoid, with the transducer at one focus and the stone at the other.

Contributor: Dave Tweed

Published February 2003