DETECTION OF URETHRAL DIVERTICULA IN WOMEN: COMPARISON OF A HIGH RESOLUTION FAST SPIN ECHO TECHNIQUE WITH DOUBLE BALLOON URETHROGRAPHY

Abstract

Purpose We compared a rapid high resolution magnetic resonance imaging (MRI) technique to contrast urethrography for the detection of urethral diverticula in women. Materials and Methods During a 19-month interval 13 patients with clinically suspected urethral diverticula were evaluated with MRI and contrast urethrography. All patients were referred by a urologist, and had clinical signs and symptoms suggesting the presence of a urethral diverticulum. Double balloon urethrography was performed in 12 patients and voiding cystourethrography was done in 1. MRI was performed using a fast spin echo T2-weighted pulse sequence and a dedicated pelvic multicoil. Following a sagittal localizer sequence 3 mm. thick axial sections were obtained from the bladder base through the entire urethra. Total imaging time was 15 minutes. Results In 7 patients MRI and urethrography were negative for urethral diverticula, and in 3 cystourethroscopy was negative. In 1 patient MRI revealed a vaginal inclusion cyst confirmed by surgery. Three patients had no other studies or procedures performed. In 6 patients MRI was positive for urethral diverticula, including 4 in whom the diverticulum was confirmed at surgery, 1 who declined surgery and 1 who was lost to followup. Of the 4 patients (75%) with a surgically confirmed diverticulum double balloon urethrogram was negative in 3. Conclusions MRI is a valuable noninvasive technique for determining the presence of urethral diverticula as well as detecting other abnormalities. In our study MRI had a higher sensitivity for detecting diverticula and a much higher negative predictive rate.