Optimisation of sonourethrography: the clamp method
To describe the clamp method for performing retrograde sonourethrography (RSUG) and contrast-enhanced voiding sonourethrography (CE-VSUG) via the transperineal approach in male adults.
Materials and methods
Prospective study of 113 males (14-86 years) with urethral strictures confirmed by urethrography who received sonourethrography via the clamp method between 2011 and 2015. The characteristic parameters of the quantitative variables were calculated and a comparative analysis of the qualitative variables was conducted using the McNemar test.
RSUG was performed successfully in all the cases (n = 113) and detected 49 cases with anterior urethral strictures; the strictures in the proximal bulbar cone in five of them (10.2%) were not visualised on retrograde urethrography (RUG) (p < 0.05). CE-VSUG was performed successfully in 97 cases and observed posterior urethral strictures in 82; the bladder neck strictures in 6 of them (7.3%) were not observed on voiding cystourethrography (VCUG) (p < 0.05). Retrograde bladder filling was achieved in approximately 6 min.
The clamp method enables RSUG and CE-VSUG to be performed simply, effectively and painlessly by a single operator. It also allows the evaluation of cases with urethromeatal alterations (stricture, hypospadias and meatotomy).
• The clamp method enables RSUG to be performed simply and painlessly.
• The clamp method requires only one operator and allows assessing urethromeatal alterations.
• RSUG shows greater capacity for detecting anterior urethral strictures than RUG.
• The clamp method achieves retrograde bladder filling in approximately 6 min.
• CE-VSUG shows greater capacity for detecting strictures than VCUG.
KeywordsClamp method Sonourethrography Ultrasound contrast Urethral stenosis Urethrography
- CE- RSUG
Contrast-enhanced retrograde sonourethrography
Contrast-enhanced voiding sonourethrography
Field of view
Visual analogue scale
Verbal descriptor scale
Benign prostatic hyperplasia
Compliance with ethical standards:
The scientific guarantor of this publication is Prof. Juan de Dios Berná Serna (Head of the Radiology Department of Virgen de la Arrixaca University Hospital).
Conflict of interest
The authors of this manuscript declare no relationships with any companies, whose products or services may be related to the subject matter of the article.
Statistics and biometry
Prof. Manuel Canteras Jordana (Head of the Statistics Department of Faculty of Medicine, University of Murcia) kindly provided statistical advice for this manuscript.
Institutional Review Board approval was obtained.
Written informed consent was obtained from all subjects (patients) in this study.
• diagnostic study
• performed at one institution
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