Pressure-controlled hydraulic dilation of the ureter: "one-step" ureteroscopy.

A controlled pressure pump was used to dilate the ureteral orifice hydraulically with irrigant flow through the ureteroscope in 50 ureters in 48 patients. The method was successful in all but 1 patient, who had a dense, fibrotic intramural segment that required extensive ureteral meatotomy before the instrument could be inserted. All subsequent procedures (stone removal, relief of obstruction or diagnostic evaluation) were successful, and there were no cases of sepsis or signs of excessive intraureteral or intrapelvic pressure. Hydraulic dilation drastically reduced the time required for ureteroscopy and probably reduced the frequency of complications. Details of the technique and the precautions are provided.