Rigid and flexible ureterorenoscopy
The rigid or flexible ureterorenoscopy (ureteroscopy, renoscopy), abbreviated URS, is an endoscopic procedure to remove urinary stones or to examine the ureter or the pelvicalyceal system. It is used for ureteral or kidney stones (up to a certain size) as well as to clarify and possibly take samples (biopsy) in case a tumour is suspected in the ureter or kidneys.
Special instruments, so-called video endoscopes, are used for URS. The surgery takes place under general anaesthesia and is thus without any pain. Providing a direct view (camera), the endoscope is entered into the urinary bladder via the urethra and then into the ureter or kidney. Since the natural orifice of the body is used, no incision is required. The modern instruments are very fine and flexible and thus facilitate reaching almost every place in the urinary tract in a gentle way. In stone treatment or sampling, very fine tools, like a special laser fibre (to break up the stone) and forceps or baskets (to remove the stone), are used as required. At the end of the surgery, a thin hose, a so-called double-J catheter (only a few millimetres wide) is placed in the renal pelvis and the ureter. This safeguards the flow of urine from the kidney into the bladder. Usually, the double-J catheter may be removed in outpatient treatment 1 week after the surgery.
The ureterorenoscopy is an effective and very safe method to treat urinary stones. Depending on the size of the stone, the position and the (anatomic) conditions in the ureter and the kidney, repeated surgery is only very rarely required. Generally, the patient is immediately “stone-free”. The use of small modern instruments makes URS a low-risk procedure. Severe complications or injuries are extremely rare.
The surgery takes place during a hospital stay of normally 2 days.
Röntgenologische Dokumentation einer flexiblen Nierenspiegelung.
(Bilder © Prof. Dr. Lahme, Siloah St. Trudpert Klinikum Pforzheim)