Transvaginal ultrasound with bowel preparation versus transvaginal ultrasound with bowel preparation and water contrast for diagnosing Recto-Sigmoid endometriosis. A systematic review and Meta-Analysis

Transvaginal ultrasound is effective in diagnosing endometriosis involving the rectosigmoid bowel. Some authors suggest enhanced detection of rectosigmoid involvement with bowel preparation. Conversely, conflicting views argue that bowel preparation may not improve diagnostic precision, yielding similar results to rectal water contrast. No existing meta-analysis compares these approaches. Our study aims to conduct a meta-analysis to evaluate the diagnostic performance of transvaginal ultrasound with bowel preparation, with and without rectal water contrast. Studies published between 2000 and 2023 were searched in PubMed, Scopus, Cochrane and Web of Science. From 561 citations, we selected nine studies to include in this meta-analysis. The study quality was assessed using QUADAS-2 (Quality Assessment of Diagnostic Accuracy Studies-2). The mean prevalence of endometriosis rectosigmoid was 43.6% (range 17,56-76,66%) in the group with bowel preparation and 64,80% (50,0-83,60%) for the group with bowel preparation and rectal water contrast. Pooled sensitivity and specificity were 93% and 94% for bowel preparation and 92% and 95% and for bowel preparation with water contrast. We conclude that, there was no significant difference between performing transvaginal ultrasound with intestinal preparation with and without water contrast. In clinical practice, the absence of a significant difference between these methods should be taken into account when making recommendations.