Diagnostic Performance of Saline/Gel Sonovaginography in Assessment of Deep Infiltrating Endometriosis at Posterior Compartments; A Systematic Review and Meta-Analysis

Sonovaginography (SVG) is a specialized ultrasound technique for evaluating certain locations of deep endometriosis (DE) in the posterior compartments. In this study, we assessed the diagnostic accuracy of saline/gel SVG in the detection of DE lesions at the rectovaginal septum (RVS) and rectosigmoid (RS). A systematic search of PubMed, Embase, and Scopus yielded 10 eligible studies with a total of 1221 patients. For gel-SVG, meta-analysis was performed and sensitivity, specificity, and diagnostic odd ratio (DOR) were calculated using a random-effects model and bivariate binomial model (95% confidence interval). To assess study quality and risk of bias, the QUADAS-2 tool was used. Based on our results, the meta-analysis on Gel-SVG studies showed for RVS a pooled specificity of 99% (94%-100%), sensitivity of 82% (44%-96%), and DOR of 274 (95.87-786.51); For RS lesions of six studies, the overall specificity, sensitivity, and DOR were 96% (93%-97%), 87% (81%-92%), and 118.79 (41.68-338.52), respectively. For vaginal fornices, pooled data from five studies showed perfect specificity of 99% (98%-100%), with a moderate sensitivity of 65% (33%-88%). Eventually, Uterosacral ligament (USL) lesions had the least DOR ratio at 31.45 (15.79-62.63), with a specificity of 97% (91%-99%) and sensitivity of 55% (31%-76%). SVG, as a low-cost, widely available, non-invasive technique, yields high diagnostic accuracy in detecting the posterior compartment DE lesions, particularly RVS and RS lesions, enhancing the accuracy of DE mapping and supporting the treatment planning.