Interventional sonography in urology. What makes ultrasound so useful?

Nephrostomy is probably the most common percutaneous ultrasound-guided intervention. Since it is the basis for access to the collecting system of the kidney, the technique is described in detail. Other forms are diagnostic pyelopuncture and antegrade stenting. Percutaneous surgery requires dilatation of the tract upon puncture in order to introduce instruments for litholapaxy, splinting strictures (endopyeloplasty) or tumor resection. Retroperitoneal accumulations of fluid outside the collecting system can be drained under sonographic view. Ultrasound is further used to localize solid structures (kidney, renal tumor, lymph nodules, prostate) for biopsy.