Which test is used to rule out urethral injury?

The retrograde cystourethrogram is the preferred test for ruling out urethral injury, particularly in cases of trauma where there is a risk of such injury. This imaging technique involves the injection of contrast material into the urethra and obtaining X-ray images, allowing for clear visualization of the urethra and the identification of any disruptions, tears, or injuries.

In situations of suspected urethral injury, especially in trauma scenarios, utilizing the retrograde cystourethrogram is crucial because it not only helps in detecting injuries but also can provide guidance for subsequent management, including surgical interventions if necessary.

Other imaging modalities, such as a CT scan of the abdomen, may be helpful in evaluating pelvic injuries and associated organ injuries, but they do not specifically visualize the urethra in a manner that permits the definitive assessment of urethral integrity. Similarly, ultrasound of the pelvic area does not provide the resolution or the detailed visualization required for assessing urethral injuries. Pelvic X-rays can identify bony injuries but are inadequate for evaluating soft tissue injuries such as those involving the urethra. Thus, the retrograde cystourethrogram remains the gold standard in these situations.