Equivocal ureteropelvic junction obstruction on diuretic renogram - Should minimally invasive pyeloplasty be offered to symptomatic patients?

Purpose Equivocal ureteropelvic junction obstruction refers to clinical symptoms and/or other radiological suggestions of possible ureteropelvic junction obstruction but with inconclusive results of obstruction on diuretic renogram. We evaluated long-term outcomes in patients with equivocal ureteropelvic junction obstruction treated with minimally invasive pyeloplasty. Materials and Methods We retrospectively analyzed the records of 125 consecutive patients who underwent minimally invasive pyeloplasty as performed by a single surgeon from May 2004 to July 2013. Of 98 patients with followup those with more than 6-month followup were included in analysis. Equivocal ureteropelvic junction obstruction, defined as half-life less than 20 minutes on diuretic renogram, was identified in 23 patients. All patients underwent transperitoneal minimally invasive pyeloplasty. We evaluated patient demographics, preoperative and postoperative symptoms and renal function. Results The 16 female and 7 male patients with equivocal ureteropelvic junction obstruction had flank pain and associated hydronephrosis on imaging. At a median followup of 20.2 months (range 7 to 75) 95.7% of patients with equivocal obstruction achieved complete symptom resolution. Mean ± SD preoperative and postoperative half-life was 14.1 ± 3.7 and 7.4 ± 4.2 minutes, respectively, for an improvement of 6.7 minutes (p <0.001). In 1 patient (4.3%) with equivocal obstruction of a complicated iatrogenic etiology treatment ultimately failed postoperatively and endopyelotomy was required. There was no statistically significant difference in clinical or radiological success between the equivocal obstruction group and the 75 patients treated with minimally invasive pyeloplasty for definitive ureteropelvic junction obstruction (p = 0.44 and 0.07, respectively). Conclusions In patients with radiographic equivocal ureteropelvic junction obstruction and flank pain minimally invasive pyeloplasty efficaciously provides symptomatic relief and functional preservation. Results are comparable to those in patients with high grade obstruction.