Diagnostic Accuracy of Retrograde Urethrogram in Determination of Urethral Stricture taking Cystoscopy as Gold Standard

Objective: To assess the diagnostic accuracy of retrograde urethrogram in determination of urethral strictures taking cystoscopy as the gold standard. Methodology: This cross-sectional study was conducted at the Department of Radiology, Sharif Medical & Dental College, Lahore from May to October 2024. After ethical approval and written informed consent, 189 patients meeting the inclusion criteria were recruited through non-probability convenience sampling technique. These patients underwent retrograde urethrogram (RUG) with contrast injection, followed by cystoscopy 4-5 days later. Demographic details and history of risk factors were recorded. Radiographic findings were assessed by a radiologist, and patients were classified as positive or negative for urethral strictures. Data were analyzed using Statistical Package for the Social Sciences (SPSS) version 25. A 2x2 table was made and diagnostic accuracy was calculated. Chi-square test was used to compare categorical variables. Results: Retrograde urethrogram detected urethral strictures in 24.3% of cases with a sensitivity of 75.56%, specificity of 91.67%, positive predictive value (PPV) of 73.91%, and negative predictive value (NPV) of 92.31%. The overall diagnostic accuracy of RUG was 87.83%. Age groups, history of urinary tract infections, and prostate surgeries had significant association with the presence/absence of strictures on RUG (p <0.05). Conclusion: The diagnostic accuracy of retrograde urethrogram was high in determination of urethral strictures taking cystoscopy as the gold standard. Urethral strictures were significantly more prevalent among older males with history of urinary tract infections and prostate surgeries.