MR imaging of the male and female urethra

Conventional radiographic contrast material-enhanced studies (eg, retrograd e urethrography [RUG], voiding cystourethrography [VCUG], double-balloon ca theter urethrography) and ultrasonography are useful in evaluating the anat omy of the urethra but are limited in demonstrating anatomic derangement of adjacent structures. Since the anatomic details of both the urethra and pe riurethral tissues can be evaluated noninvasively with magnetic resonance ( MR) imaging, this modality can be used as an adjunctive tool for evaluation of urethral abnormalities. In patients with congenital anomalies, MR imagi ng is reserved for cases of intersex anomalies or complex genitourinary ano malies, in which evaluation of internal organs is essential. MR imaging may demonstrate diverticula that are not seen on radiographic contrast-enhance d studies, including VCUG, RUG, or double-balloon catheter study. In cases of inflammation MR imaging can demonstrate, not only inflammatory infiltrat ion around the urethra but also the presence of a periurethral abscess or s inus tract. In cases of trauma, MR imaging is helpful in assessing the pres ence and extent of anterior or posterior urethral injury and predicting the occurrence of complications. At MR imaging, a fistula can be seen as a dir ect communicating channel with an adjacent organ. In patients with urethral tumors, the major role of MR imaging is in local staging.