[Flexible endoscopy of the upper urinary tract. A new minimally invasive method for diagnosis and treatment].

Retrograde intrarenal surgery (RIRS) utilizing flexible, actively deflectable instruments has become a valuable asset in the diagnosis of upper urinary tract pathology and the treatment of stone disease. Flexible endoscopic surgery of the proximal ureter and in the intrarenal collecting system constitutes the natural extension of rigid instrumentation in the upper urinary tract. At our institution retrograde ureteral and intrarenal surgery has become an +integral part of our diagnostic and therapeutic armamentarium. This is documented by almost 300 treatments and diagnostic procedures performed in the upper urinary tract over the past 3 years.