Role of multiphasic helical computed tomography in planning surgical treatment for pelvi-ureteric junction obstruction

OBJECTIVE To evaluate the role of multiphasic helical computed tomography (CT) in planning surgical treatment for pelvi-ureteric junction obstruction (PUJO). PATIENTS AND METHODS Multiphasic helical CT was used in 60 consecutive patients (mean age 32 years, sd 13.72) with primary PUJO. The different images were interpreted before surgery by a urologist and radiologist. The number, type and relation of the crossing vessels to the PUJ were detected. Pyeloplasty (open or laparoscopic) was used in patients where there was a significant crossing vessel (i.e. > 2 mm in diameter and passing at the PUJ) or with ballooning of the renal pelvis. Endopyelotomy (antegrade or retrograde) was used in the other patients. Subjective and objective success rates were determined 3-6 months after treatment and then every 6 months. RESULTS Hyperdense renal stones were detected in precontrast images in 15 patients, significant crossing vessels in 33 (55%), and anterior malrotation of the renal pelvis in 23 (38%; 19 associated with significant crossing vessels, i.e. ureterovascular hydronephrosis). A large para-pelvic cyst compressing the PUJ and upper ureter was detected in one patient. Pyeloplasty was used in 45 patients, among whom the sensitivity of multiphasic helical CT in detecting crossing vessels was 97%, the specificity 92% and accuracy 96%. Uncomplicated endopyelotomy was used in 14 patients and percutaneous aspiration of the para-pelvic cyst in one. CONCLUSION Multiphasic helical CT can accurately delineate the spatial anatomy of the renal and peri-renal area; it may be important in planning surgical treatment for PUJO, especially when endopyelotomy is considered.