Endoscopic features of impacted ureteral stones

Purpose: We retrospectively evaluated endoscopic findings in 165 patients with impacted ureteral stones to determine the incidence of associated ureteral lesions and predisposing factors for such lesions. Materials and Methods: From July 1993 to March 2003 we performed retrograde endoscopic treatment in 165 patients with ureteral stones that had been impacted for more than 2 months. Average maximum stone diameter was 15.0 mm and the mean duration of impaction was 17.6 months. Treatment was done with small caliber ureteroscopes and a laser lithotriptor. We analyzed the endoscopic findings and determined the outcome by reviewing the clinical records and radiographic studies. Results: Endoscopic observation revealed inflammatory ureteral polyps associated with calculi in 51 patients (30.9%). Endoscopic biopsy of 5 polyps was performed. Histological examination showed no malignancy and only chronic granulomatous inflammation of the ureter. Endoscopic observation also detected ureteral stricture in 28 patients (17.0%). Patients with polyps and strictures had long-term impaction (median 12 and 24 months, respectively), which was significantly longer than in patients without ureteral lesions (4 months). Conclusions: Endoscopic observation revealed that long-term impacted stones were frequently associated with ureteral polyps and strictures. Although concurrent ureteral lesions can make it more difficult to approach the calculus in patients with impacted stones, we found that a small caliber flexible endoscope was effective and laser fragmentation could be achieved easily.