Magnetic resonance urethrography in comparison to retrograde urethrography in diagnosis of male urethral strictures: is it clinically relevant?

OBJECTIVE: To compare the clinical relevance of retrograde urethrography (RUG) and magnetic resonance (MR) urethrography in evaluating male urethral strictures.

METHODS: Between January and April 2004, 20 men were referred to our institute for management of urethral strictures. The patients were investigated by conventional RUG and multiformat MR urethrography. The patients were examined by urethroscopy under anesthesia to be followed by definitive endoscopic or open operative intervention. The radiologic data were compared by endoscopic as well as operative findings in all the patients.

RESULTS: Ten patients were managed by visual internal urethrotomy (VIU) and two by dilatation under anesthesia; two showed normal urethral caliber. Four patients required open urethral reconstructive procedures. Two patients underwent radical cystectomy and cutaneous diversion because of associated bladder or urethral malignancy. Although overall accuracy for diagnosis of urethral strictures was equal between both modalities (85%), MR urethrography provided extra clinical data in seven patients (35%). It was superior to RUG in judging the urethral stricture length in three patients, diagnosing a urethral tumor in one, detecting associated bladder mass in one, characterizing the site of urethra-rectal fistula in one, and accurately delineating the proximal urethra in the last patient. Unlike RUG, MR urethrography provided adequate information about the degree of spongiofibrosis in all patients.

CONCLUSION: MR urethrography is a promising tool for defining male urethral strictures and can provide extra guidance for treatment planning that cannot be obtained with RUG.