Scoring system for predicting ovarian necrosis in adnexal torsion using an ultra-short optimized MRI protocol

To evaluate a MRI scoring system predicting haemorrhagic necrosis in adnexal torsion with intraoperative and/or histopathological correlation using an abbreviated and optimized MRI protocol.

This retrospective observational study includes patients with adnexal torsion who underwent Magnetic Resonance Imaging(MRI) and surgery. T2 sequences were evaluated by three observers of varying experience for following findings: Hypo-intensity of ovarian stroma, around the follicle, cyst wall or ovarian capsule and the twisted pedicle. Hypo-intensities in the above and a thick cyst wall were considered as predictors of necrosis. A scoring system was created based on the number of positive findings. MRI was correlated with intraoperative and histopathological findings. Lesions showing haemorrhagic necrosis were considered true positives.

43 women with torsion were included. 74.4% were secondary to a lead point and 25.4% were without one. Hypointensity score of 2 or more had the highest diagnostic accuracy and inter-reader agreement in predicting necrosis (R1-sensitivity: 92%, specificity: 89%, positive predictive value (PPV): 92% and negative predictive value (NPV): 89%, R2-sensitivity: 92%, specificity: 94%, PPV: 96% and NPV: 90% and R3-sensitivity: 92%, specificity: 83%, PPV: 89% and NPV: 89%).

In patients with suspected adnexal torsion, optimized MRI using T2 weighted sequences will serve as a rapid and effective single imaging modality for diagnosing adnexal torsion and accurately predicting necrosis thereby triaging the patients for appropriate management.