Sonographic sign of intermittent dilatation of the renal collecting system in 10 patients with vesicoureteral reflux.

PURPOSE

Renal sonography is an accepted primary imaging modality for evaluating the pediatric urinary tract. We report a new sonographic finding associated with vesicoureteral reflux (VUR).

METHODS

Ten patients underwent sonographic evaluation of the kidneys and were noted to have intermittent renal collecting system dilatation that expanded and contracted during real-time scanning. These patients were further evaluated with voiding cystourethrography.

RESULTS

All 10 patients were proven to have VUR on the side of the sonographic abnormality. Four patients had bilateral VUR for a total of 14 refluxing renal units. Of these 14 renal units, 1 was sonographically normal. Five of the 14 renal units had grade V VUR that required surgical reimplantation of the ureter.

CONCLUSIONS

This new finding of intermittent renal collecting system dilatation may become an important predictor of VUR. The finding warrants further evaluation even when detected in patients not suspected of having VUR who are undergoing renal sonography for other reasons.