The twin amplatz sheath method: a modified technique of percutaneous cystolithotripsy for large bladder stones in female patients.

To minimize the operative time and to avoid open cystolithotomy in women with large bladder stone (>5 cm), we present here a modification of percutaneous cystolithotomy, a well-described standard procedure for urinary bladder stones. With this technique, suprapubic percutaneous access was achieved under cystoscopic guidance. The suprapubic tract was dilated and an Amplatz sheath of 30 Fr was placed. Simultaneously, the urethra was sequentially dilated with fascial dilators and a 28 Fr Amplatz sheath was guided into the bladder and the foot end of the table lowered to 20° to facilitate high-speed outflow of irrigant and stone particles. A 26.5 Fr nephroscope was passed through the suprapubic Amplatz sheath and the stone was fragmented by intracorporeal pneumatic device keeping the stone close to the proximal end of the urethral Amplatz. These maneuvers help in washing out stone fragments periurethrally and keeping the endoscopic vision clear while breaking the stone.