Diagnostic values of MRI indexes for polycystic ovary syndrome

Abstract

Background Magnetic resonance imaging (MRI) is a useful non-invasive modality for observation of ovarian morphologic characteristics. Few studies have focused on the value of MRI-derived indexes in reproductive-aged women with polycystic ovary syndrome (PCOS). Purpose To assess the diagnostic value of MRI in women with PCOS. Material and Methods This prospective case-control study included 85 women with PCOS and 50 controls who underwent pelvic MRI during 2017–2019. Ovarian volume (OV), follicle count (FC; counts of follicles sizing 2–3, 4–6, 7–9, 2–9 mm, respectively), follicular peripheral distribution, absence of a dominant follicle and stromal to total area ratio (S:A) were determined with MRI. The diagnostic value (sensitivity, specificity, area under the receiver operating characteristic curve [AUC]) of OV, FC2–9, and follicular peripheral distribution for PCOS were assessed. Results The AUCs were 0.94 for OV, 0.96 for FC2–9, and 0.78 for follicular peripheral distribution. The optimal threshold to detect PCOS was 8.5 mL for OV (sensitivity 78%; specificity 96%) and 26 for FC2–9 (sensitivity 85%; specificity 98%). Sensitivity and specificity were 73% and 82% for follicular peripheral distribution, respectively. Reproducibility was perfect for OV (ICC = 0.96) and absence of a dominant follicle (k = 0.85), substantial for FC2–9 (ICC = 0.79) and S:A (ICC = 0.69), and moderate for follicular peripheral distribution (k = 0.56). Conclusion Detected by MRI, OV >8.5 mL or FC2–9 >26 are accurate for diagnosing PCOS.