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

Abstract

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).

An innovative method for occluding the urethral meatus and accessing urethra strictures in retrograde urethrography in males

“…However, the single voiding method may not demonstrate certain abnormalities of the male anterior urethra because the normal anterior urethra is not fully distended [13]. To fully visualize the actual urethral caliber by lling the urethral lumen with contrast liquid, retrograde injection of contrast medium should be performed and the external meatus of the urethra should be blocked off to prevent contrast from running out [3,4,13].…”

“…Another frequently used method is the clamp system, which tightly bands the balanoprepucial sulcus with a padded ring [13,18]. The 2-4 cm of the distal urethra (inside the glans) is not visualized in the retrograde study [3]. Ayoob et al reported that cine imaging or spot images at 2-4 frames/sec could be used to visualize the far anterior urethra as the catheter is removed and contrast empties[8].…”

“…X-ray urethrography remains the essential procedure of assessing the urethra stricture disease [1], which includes retrograde urethrography (RUG) and voiding cystourethrography (VCUG) [2]. For fulling urethral lumen with contrast liquid to visualize actual urethral caliber, the external meatus of urethra should be blocked off to avoid contrast running out of the meatus [3,4]. Conventional options include Foley's catheter [2], penis clamp [3,4], meatus adapter [5].…”

“…For fulling urethral lumen with contrast liquid to visualize actual urethral caliber, the external meatus of urethra should be blocked off to avoid contrast running out of the meatus [3,4]. Conventional options include Foley's catheter [2], penis clamp [3,4], meatus adapter [5]. This study introduces an innovative device for occluding the meatus, and its e cacy and safety are assessed.…”

Urethrocystography: a guide for urological surgery?

“…40,41 A study published in 2021 on CT-RUG using the clamp method reported no pain in 81% of patients and showed that this technique had better diagnostic efficacy in cases of periurethral fistula, urethral stent, previous urethroplasty, and urethral lithiasis compared to RUG and RSUG. 42 Recent articles have shown the utility of magnetic resonance imaging (MRI) in urethral stricture disease. This technique can detect spongiofibrosis, reducing the limitation of the subjective SUG examination and giving detailed information about periurethral tissue and anatomic relationships.…”