Endometriosis diagnosis: a retrospective study on the use of transvaginal ultrasound, sonovaginography and magnetic resonance imaging

Objective: To provide estimates of the diagnostic accuracy of transvaginal ultrasound, sonovaginography and magnetic resonance imaging for the diagnosis of ovarian endometriosis and deep endometriosis. Methods: This was an observational, retrospective study carried out in a tertiary center. Consecutive patients who underwent surgical procedures between 2010 and 2023 for diagnosis and treatment of endometriosis were included. The index tests were transvaginal ultrasound, sonovaginography and magnetic resonance imaging. Accuracy of these tests to identify lesions of endometriosis was assessed for different sites, relative to surgical findings. Data was obtained from imaging and surgical reports. Sensitivity, specificity, positive and negative predictive values were calculated for each diagnostic method. Results: Out of 301 patients who underwent surgery, 195 (64.8%) were evaluated with transvaginal ultrasound, 99 (32.9%) had a sonovaginography performed and 167 (55.5%) were evaluated with magnetic resonance imaging. All but 3 (0.01%) patients had endometriosis confirmed through surgical visualization. The sensitivity and specificity for ovarian endometriosis were 95.2% and 83.1% for transvaginal ultrasound and 91.0% and 80.5% for magnetic resonance imaging, respectively. Regarding deep endometriosis, the sensitivity and specificity were 84.1% and 54.5% for sonovaginography and 90.3% and 60.0% for magnetic resonance imaging, respectively. Conclusion: Transvaginal ultrasound was highly accurate for the diagnosis of endometriomas and, when used alongside sonovaginography it had important value in the diagnosis of deep endometriosis as well. Both sonovaginography and magnetic resonance imaging showed similar performance in diagnosing deep endometriosis and stand as reliable diagnostic tools.