A prospective study of endoluminal ultrasound versus computerized tomography angiography for detecting crossing vessels at the ureteropelvic junction

Purpose: Crossing vessels at the ureteropelvic junction are associated with bleeding complications and a higher risk of failure after endopyelotomy. W e compared computerized tomography (CT) angiography and endoluminal ultraso und far detecting crossing vessels before planned endopyelotomy. Materials and Methods: Preoperatively patients underwent CT angiography. In traoperative evaluation included retrograde ureteropyelography, endoluminal ultrasound and ureteroscopy, Intraoperative findings were used to direct t reatment. Results: Endoluminal ultrasound detected 19 crossing vessels in 14 of 20 pa tients (70%), while CT detected 9 crossing vessels in 7 (35%). Endoluminal ultrasound identified a septum between the ureter and renal pelvis in 7 pat ients (35%) but CT demonstrated none. On the basis of imaging findings we s elected 5 patients for pyeloplasty, and endoluminal ultrasound accurately p redicted the absence or presence of crossing vessels in all 5. CT angiograp hy was accurate in 3 patients. However, in 2 patients a total of 4 vessels were missed by CT. A total of 15 patients underwent endopyelotomy with no b leeding complications. The presence or absence of a septum on endoluminal u ltrasound was confirmed in all patients. Imaging findings altered the treat ment chosen in 4 patients and changed the direction of the incision at the ureteropelvic junction in another 4. Clinical and radiographic success was achieved in all 13 patients (100%) with adequate followup. Conclusions: Endoluminal ultrasound was more sensitive than CT angiography for identifying crossing vessels and septa. Treatment based an endoluminal ultrasound findings may decrease complications and improve the results of m inimally invasive treatment for ureteropelvic junction obstruction.