Balloon dilation of the ureter for ureteroscopy.

Balloon dilation catheters have been used extensively for percutaneous transluminal dilation of vascular narrowings. A recent urological application has been the use of a balloon to dilate acutely the normal ureteral orifice and intramural ureter for the purpose of performing transurethral ureteroscopy. Complications of balloon dilation may result if over inflation and bursting of the balloon occur followed by ureteral injury. We report the pressure needed to dilate the ureter adequately in 122 patients during an 18-month period. Adequate dilation was achieved in 93 patients (78 per cent) at pressures of 8 atmospheres or less, while 27 (22 per cent) required more than 10 atmospheres of pressure. Balloon dilation was not satisfactory in 2 patients (2 per cent) but it was accomplished by metal bougies. Our results confirm the safety and efficiency of balloon dilation to facilitate ureteroscopy. Important safeguards when using this method include the use of balloons designed specifically for ureteral dilation, slow balloon inflation to allow for ureteral accommodation and the use of fluoroscopy to judge the end point of dilation.