Stryker frame gantry modification for extracorporeal shock wave lithotripsy to circumvent positioning problems

From July 1986 through December 1989, 45 patients with renal or biliary calculi were treated on a Dornier HM3* lithotriptor using a Stryker frame gantry modification. The modification was necessary due to inability to position the patients in the standard gantry. The situations that required nonstandard positioning techniques included stones in the distal or mid ureter, renal transplant, gallbladder or common bile duct, and unusual body habitus, such as myelomenigocele, bilateral lower extremity amputations and children with stones. Positioning with adequate focus of the shock wave was achieved in 87% of the patients and fragmentation was achieved in 89%. The Stryker frame gantry modification is an excellent method to circumvent positioning problems with the Dornier HM3 lithotriptor, extending lithotripsy capability to patients who might otherwise not be candidates.