Imaging of male urethra.

The male urethral imaging and pathology is not widespread in the radiology literature because this part of the urinary tract is easily studied by urologists with clinical or endoscopic examinations. Ultrasonography and MR imaging are increasingly being used in association with voiding cystourethrography and retrograde urethrography. The posterior urethra is being studied with voiding cystourethrography or voiding sonography which allows the detection of bladder neck pathology, post-surgical stenosis, and neoplasms. The functional aspects of the bladder neck and posterior urethra can be monitored continuously in patients with neuromuscular dysfunction of the bladder. The anterior urethral anatomy and pathology is commonly explored by retrograde urethrography, but recently sonourethrography and MR imaging have been proposed, distending the lumen with simple saline solution instead of iodinated contrast media. They are being used to study the urethral mucosa and the periurethral spongy tissue which can be involved in the urethral pathologies such as strictures, diverticula, trauma, and tumors. Imaging has an important role to play in the study of the diseases of the male urethra since it can detect pathology not visible on urethroscopy. The new imaging techniques in this area, such as sonography and MR, can provide adjunct information that cannot be obtained with other modalities.