Impact of 3-dimensional helical computerized tomography on selection of operative methods for ureteropelvic junction obstruction

Purpose: The studied the feasibility of imaging the direct correlation between crossing vessels and obstructed ureteropelvic junction with helical (spiral) computerized tomography (CT) for selecting surgical repair of symptomatic ureteropelvic junction obstruction. Materials and Methods: From July 1995 to December 1995, 4 select patients with symptomatic ureteropelvic junction obstruction underwent contrast enhanced helical CT. In addition to transaxial images, 3-dimensional reformatted images were used for evaluation. Results: We identified 2 cases of ureteropelvic junction obstruction due to crossing vessels regarded as ureterovascular hydronephrosis, which is characterized by the spatial relationship between malrotated renal pelvis and anterior crossing vessels. Laparoscopic or open repair-was performed in these 2 patients and operative findings were in agreement with prospective helical CT interpretation. Antegrade endopyelotomy was performed successfully for the remaining 2 patients. Conclusions: The 3-dimensional helical CT is reliable in detecting ureterovascular hydronephrosis preoperatively and in presenting better operative methods for ureteropelvic junction obstruction.