Figure 12a. Endometriosis in a 37-year-old woman with RLQ pain and a right adnexal mass at US. (a) Axial T1-weighted GRE image shows two lesions (arrows) with homogeneous high signal intensity in the pelvis. (b) Sagittal T2-weighted fast SE image shows heterogeneous decreased or low signal intensity (shading) in the two lesions (arrows), which are located immediately superior to the uterus (U). Gadolinium-enhanced MR imaging showed no enhancement within the lesions. Endometriomas were confirmed at surgery and pathologic analysis.