Presentation
Pelvic pain for one year.
Patient Data
Right ovarian cystic lesion. It appears hyperintense on T1 and T1FS images and shows T2 shortening (shading) due to repeated hemorrhage within the lesion.
The shading sign is an MRI finding typically seen in an endometrioma. The sign is seen on T2 weighted sequences of lesions that are hyper-intense on T1, and consists of low signal (T2 shortening) affecting variable portions of the cyst.
Case Discussion
An endometrioma (chocolate cyst) is a localized form of endometriosis (usually within the ovary). It contains dark degenerated blood products following repeated cyclical hemorrhage.