Electrohydraulic gall stone removal system - uses coaxial cable with inner electrode designed to produce required shock wave formation

摘要

The electrohydraulic method of removing stones from the urinary channels, uses a resilient cable (2) for generating the electrical pulses. This is coaxial with the inner core (9) having a different length from the outer layer (8) so as to produce a required shock wave formation (15). The outer layer is formed by a helically wound metal band (11) and terminates at the tip in an outer electrode (4). The inner member (5) forms the other electrode, and may have pointed tip (7) which extends from the outer electrode or may have a funnel shaped ending (13) inset within the outer electrode. Between them is an insulating sleeve.