Retrograde urethrography and voiding cystourethrography are the modalities of choice for imaging the urethra. Cross-sectional imaging modalities, including ultrasonography, magnetic resonance (MR) imaging, and computed tomography, are useful for evaluating periurethral structures. Retrograde urethrography is the primary imaging modality for evaluating traumatic injuries and inflammatory and stricture diseases of the male urethra. Sonourethrography plays an important role in the assessment of the thickness and length of bulbar urethral stricture. Although voiding cystourethrography is frequently used to evaluate urethral diverticula in women, MR imaging is highly sensitive in the demonstration of these entities. MR imaging is also accurate in the local staging of urethral tumors.
Copyright RSNA, 2004.