Retrograde urethrography in children: a decade of experience at a children's hospital

Background Retrograde urethrography (RUG) is a radiologic procedure that optimizes imaging evaluation of the urethra, particularly in settings of difficulty with micturition or urethral injury. Objective To review our experience with RUG at a large pediatric radiology practice. Materials and methods We conducted a retrospective review of medical records and fluoroscopic images of RUGs performed from January 2010 to December 2020. Results We identified 180 RUG exams ( median frequency 17 exams per year), all in male children (median age 13 years). The most common indications were stricture (42%; n=76), postsurgical evaluation (34%; n=62) and trauma (16%; n=29). The most commonly used catheter was Foley (40%; n=72), with a median catheter size of 5 French (Fr) for infants younger than 1 year, 7 Fr for children ages 1-5 years and 8 Fr for children older than 5 years. About a third of the children ( 57; 32%) had combined voiding cystourethrography ( VCUG)-RUG exams. Water-soluble contrast agent, either 17% or 43% Cysto-Conray, was used. Most RUG exams were normal ( 46%; n=83). The most common urethral pathology was stricture (30%; n=54), commonly involving a bulbar urethra (n=26). Urethral trauma was seen in 11 children (6%), 10 bulbar and 1 membranous. Most children with stricture were surgically treated (n=40; 74%), whereas most children with trauma were conservatively treated (n=8; 73%). The remaining diagnoses included diverticula, polyps, valves, fistulas and duplications, constituting <17% of our sample; most of these were surgically treated. Four exams (2%) were non-diagnostic. RUG showed 89% sensitivity and 97% specificity compared to cystourethroscopy/VCUG findings. Technical difficulties occurred in 14 (8%) children (e.g., pain or inappropriate catheter seal). Conclusion Our experience indicates that when catheterization techniques are properly tailored, RUG provides a useful and successful radiologic method of evaluating the pediatric male urethra.