Purpose : To determine the usefulness of transrectal ultrasound (TRUS) and to compare TRUS with intravenousurography (IVU) in the evaluation of distal ureteral calculi. Materials and Methods : TRUS and IVU were perfomedin 24 patients with distal urete...
Purpose : To determine the usefulness of transrectal ultrasound (TRUS) and to compare TRUS with intravenousurography (IVU) in the evaluation of distal ureteral calculi. Materials and Methods : TRUS and IVU were perfomedin 24 patients with distal ureteral calculi. Using TRUS, we evaluated the presence and size of calculus, type of ureteral jet at the affected site and diameter of ureter proximal to calculus, and using IVU evaluated the presence and size of calculus, degree of ureteral obstruction, and degree of hydroureter. TRUS and IVU findings, were compared. Results : In each patient, TRUS detected calculus of the distal ureter ; in only 18cases (75%),were the calculi demonstrated with IVU. In 18 cases where calculi were detected by both modalities, averagecalculus size was 4.5 $\times$ 3.0mm (longest and shortest dimensions) by IVU, and 6.1 $\times$ 3.7 mm by TRUS. Betwee TRUS and IVU(p<0.05) there was a statistically significant difference in the longest dimension of calculi. Color Doppler imaging revealed three patterns of ureteral jets in TRUS : normal periodic jet (7 cases) ; continuous low-level flow (8 cases) ; and no detectable jet (9 cases). There was a positive correlation between type of ureteral jetson TRUS and between degree of obstruction on IVU (r=0.59, p<0.05). There was, however, no significant correlation between diameter of ureter proximal to calculus on TRUS and degree of hydroureter on IVU (r=0.32, p>0.05). Conclusion : TRUS appears to be a useful adjunctive method for the evaluation of distal ureteral calculus.