[Urodynamic studies of the upper urinary tract. II. Pyelo-ureteral dilatation. Reversibility prediction test]

For the correct performance of upper urinary tract repairs, it is essential to use methods which provide the necessary information concerning the potential reversability of the dilatation. This article analyzes the physiopathological foundations on which these methods must be based, and comments on the different procedures in common practice, such as the concept of radiological tonicity, peroperative histology, and preoperative draining. Special mention is made of anterograde urometry associated with simultaneous dynamic radiology, which provide precise information concerning the intraluminal pressure and the muscularization of the ureteral wall.