Resolution of hydronephrosis after uterine artery embolization for fibroids

To determine the prevalence, predisposing factors, and resolution of hydronephrosis among patients undergoing uterine artery embolization (UAE) for fibroids.

From October 2004 to May 2008, 1,114 patients underwent UAE at an academic medical center. Hydronephrosis was found on angiographic images in 101 patients. In 34 of these patients, 3-month ultrasound follow-up was available. The angiographic images were graded for hydronephrosis severity by three interventional radiologist reviewers. The degree of residual hydronephrosis was obtained from ultrasound images or reports in 3-month follow-up imaging. Descriptive statistics summarizing outcomes and interobserver agreement regarding hydronephrosis grade were calculated. In a parallel assessment, prospectively gathered baseline data available from 776 patients undergoing UAE were analyzed to identify predisposing factors to hydronephrosis.

Among the 34 patients with hydronephrosis and appropriate follow-up, resolution occurred in 28 of 34 (82%) patients. Among the entire study group, 9.0% (101 of 1,114) of patients had unilateral or bilateral hydronephrosis. Hydronephrosis was less frequent in left kidneys (4.5% [35 of 776]) than right kidneys (6.3% [49 of 776]; P = .013). The mean uterine volume in the group with hydronephrosis was greater than in the group without hydronephrosis (1,041 cm(3) vs 609 cm(3); P < .0001), and the mean dominant fibroid volume was also greater (233 cm(3) vs 147 cm(3); P < .0001).

These results suggest that UAE may result in resolution of hydronephrosis in a notable number of cases. Large uterine size and dominant fibroid size was associated with hydronephrosis.