Doppler and real-time ultrasound in renal stone surgery.

In stone surgery the operative approach aims not only at complete removal of stones, but also at minimizing damage to the intrarenal arteries and parenchyma. In complicated staghorn or calyceal stones, our concept is to remove as many stones as possible through an extended pyelocalicotomy and the residual calyceal stones via minimal radial nephrotomies. To accomplish an atraumatic nephrotomy, the shortest transparenchymal route should be chosen, and damage to the intrarenal arteries must be avoided. Doppler sonography for intraoperative localization of the intrarenal arteries and combined B-scan sonography for intraoperative localization of stones allow an avascular, atraumatic nephrotomy, in which clamping of the renal artery and cooling are no longer necessary. In 35 operations with a total of 109 radial nephrotomies, clamping of the renal artery was required in only 2 cases. By comparing the preoperative and 6-week postoperative functional results, split 131I-hippuran clearance demonstrated only 7% loss of function of the operated kidneys.