OC24: The role of magnetic resonance imaging and transvaginal ultrasonography in patients with an adnexal mass and chronic pelvic pain or infertility

The purpose of this study was to compare the diagnostic accuracy of transvaginal ultrasound and magnetic resonance imaging (MRI) in patients with an adnexal mass at high risk of ovarian endometriosis owing to the presence of chronic pelvic pain and/or infertility. A total of 37 adnexal masses in 28 patients were included in the study and submitted to MRI and transvaginal ultrasound evaluation before surgery for the presence of an adnexal mass associated with pelvic pain, infertility, dispareunia or dysmenorrhea. The visualization of round-shaped homogeneous hypoechoic ‘tissue’ of low-level echoes within the ovary was chosen as an ultrasonographic finding characteristic of endometrioma. MRI was carried out on a 1.5-T system using sequences TSE, T1, T2 and fat-suppressed T1-weighted before and after intravenous injection of gadolinium. Twenty of 37 masses were found to be an endometrioma at surgery. The sensitivity, specificity, positive (PPV) and negative (NPV) predictive values, positive (LR+) and negative (LR−) likelihood ratios, and kappa values for transvaginal ultrasonography and MRI are reported in the table. The pretest probability in this study population was 54% and this probability was raised to 89% in the presence of an ultrasonographic finding and decreased to 17% when this finding was absent. Using MRI the results were similar. Of the 17 cases of ovarian endometriosis suspected by MRI, 15 were confirmed by surgery. The two false positives were the same cases missed by transvaginal ultrasonography. Transvaginal ultrasonography in a population of women with adnexal masses associated with chronic pelvic pain and/or infertility showed similar accuracy to MRI. Due to the lower cost and invasivity, ultrasonography should be recommended in patients at high risk of endometriosis and also for programming presurgical medical treatment.