A New Technique for Computed-Tomography Urethrography in Males: The Clamp Method

The aim of the present study is to describe and evaluate a new technique for performing Computed-Tomography Retrograde Urethrography (CT-RUG). Males with urethral anomalies detected by retrograde urethrography (RUG) and/or retrograde sonourethrography (RSUG) underwent CT-RUG using the clamp method and three radiologists evaluated the anomalies in each technique separately and blindly. CT-RUG was done successfully in all the cases (n = 22), with means of 6 min duration and 95 mL of contrast; no pain was reported by 81% of the patients (VAS: 0) and very mild pain by the rest (VAS: 0.5–1.2). CT-RUG showed better diagnostic efficacy in cases of periurethral fistula (n = 8), urethral stent (n = 3), previous urethroplasty and urethral lithiasis (n = 2), a similar accuracy to RSUG for measuring the length of anterior urethral strictures (n = 9) and greater accuracy than RUG (p = 0.008). Six cases received 2 CT sweeps, with an effective dose of 4.96 mSv, and the remaining 16 had 1 sweep and received 3.456 mSv. To the best of our knowledge, this is the first study to describe the clamp method for CT-RUG, a method that is effective and comfortable for both the patient and the operator (retrograde infusion of contrast).