Contrast ultrasound of the urethra in children

The aim of this study was to report our experience with transperineal ultrasound in studying the urethra, as a complementary technique to contrast-enhanced voiding urosonography (VUS). The VUS was performed in 350 patients (244 males, 106 females) less than 4 years of age, and complemented with perineal US. Ultrasound of the kidneys and bladder was obtained before and during bladder filling and post-voiding. The urethra and the neck of the bladder were evaluated sagittally by transperineal ultrasound (5–7.5 MHz) before, during, and after voiding. Only cases of posterior urethral valves diagnosed at VUS were followed by voiding cystourethrography (VCUG), which was performed on a different day. A satisfactory evaluation of the urethra was obtained in 332 cases (94.86%): (a) normal urethra (n=328); and (b) posterior urethral valves (n=4). In the latter 4 cases there was concordance between results at VUS and VCUG. Eighteen cases (5.14%) were excluded from the study because the quality of the examination was suboptimal. Transperineal US offers an initial imaging modality for studying urethral pathology and thus may complement VUS.