Ureteral Calculi : The Diagnostic Value of Combined KUB and Ultrasound

To evaluate the diagnostic value of combined KUB and ultrasound in patients with ureteral calculi. We retrospectively reviewed the KUB and ultrasound findings in 71 cases of clinically,radiologically, and surgically confirmed ureteral calculi. We evaluated the diagnostic sensitivity of each method respectively, and then compared the sensitivity of each method with that of combined studies. The overall diagnostic sensitivities in detection of the ureteral calculi were 92.9% for KUB and 78.8% for ultrasound.The sensitivities in detection of the upper ureteral calculi were 95.1 (39 / 41) and 82.9% (34 / 41), and those in detection of the lower ureteral calculi were 90.0 (27 / 30) and 73.3% (22 / 30), respectively. On the ultrasonography, the false negative rate in detection of ureteral calculi was 21.1%. The sensitivity of ultrasound in detection of acute urinary obstruction by ureteral calculi was 87.3%. When both studies were combined, the diagnostic sensitivities were 92.9 (66 / 71), 97.5 (40 / 41) and 86.6% (26 / 30) for overall, upper and lower ureteral calculi, respectively. Combined KUB and ultrasound was a sensitive method for detection of ureteral calculi and for determination of acute urinary obstruction by reducing the number of false negative ultrasound results in patients with ureteral calculi