To review the objective and subjective success rates of robotic-assisted laparoscopic pyeloplasty in symptomatic patients with radiographic findings suggestive of uretero-pelvic junction obstruction (UPJO), but equivocal renal scans (diuretic T1/2 <20 minutes).

We reviewed 77 patients with symptomatic UPJO, who underwent robotic-assisted laparoscopic pyeloplasty between August 2006 and March 2013. We grouped patients by renal scan findings into 1 of 2 groups, obstructed (diuretic T1/2 ≥20 minutes) or equivocal (diuretic T1/2 <20 minutes). All patients were symptomatic and had radiographic findings suggestive of UPJO (eg hydronephrosis).

Mean age was 40.7 years (range 17-80) with 70% female. UPJO occurred 44% left and 56% right, with 92% presenting with flank pain. Of 77 patients, 45 had obstruction on renal scan, with 41 (91%) having resolution of obstruction postoperatively and 44 of 45 (98%) having complete resolution of their initial symptoms. Thirty-two patients had equivocal findings with mean diuretic T1/2 of 12.6 minutes (range: 5.5-19.26) on renal scan. In this latter group, patients had significantly less of a decrease in their diuretic T1/2 postoperatively (4 vs 64 minutes, P = .018) and reported less pain resolution (53% vs 98%, P ≤.001) than group 1.

Many studies have demonstrated excellent success of pyeloplasty, with most series including patients meeting strict diagnostic criteria for obstruction. Our study examines outcomes in patients with clinically symptomatic UPJO and equivocal diuretic renography. In our cohort, equivocal patients were significantly less likely to have subjective resolution of symptoms than patients in the obstructed group.