TURNEY B., Heers H.
Ureteroscopy (URS) plays an important role in the diagnostic pathway for visible and persistent nonvisible hematuria from the upper urinary tract after initial radiological assessment. If a tumor of the upper urinary tract is suspected, URS is the most valid diagnostic step and allows for histology sampling. Other indications for diagnostic URS are suspected ureteric stricture and hydronephrosis of unknown origin. The diagnostic value is higher in the absence of a ureteric stent. Digital scopes may offer superior imaging quality in comparison to fibre optics. Every diagnostic URS includes a thorough cystoscopy. Manipulation in the ureter and collecting system should be as atraumatic as possible. After intubation of the ureteric orifice, a retrograde ureteropyelogram is performed. The ureter up to the pelviureteric junction is inspected with a semirigid ureteroscope; a flexible scope is used to inspect the collecting system. Urine cytologies should be obtained at different levels. Biopsies of suspicious lesions can be obtained with forceps or – for exophytic tumors – with stone baskets. Tumor grading is reliable but the local stage is often underestimated. In select cases, tumors of the upper tract may be treated endoscopically using holmium:YAG laser. A number of optical and fluorescence techniques have been introduced to enhance the diagnostic accuracy of URS but further studies are required to objectify their reliability.