Hydatid disease: MR imaging of calvarium and superior sagittal sinus involvement.

Extra-axial hydatid disease (HD) is rare and may create a diagnostic challenge. Herein, we report an extremely rare case of calvarial HD with superior sagittal sinus invasion and an extension to the scalp with unusual magnetic resonance imaging findings simulating osteomyelitis and abscess. Recognition of detached endocystic membranes was the most important clue for the correct diagnosis. HD should be included in the differential diagnosis for a patient having a destructive skull lesion with peripheral enhancing extra-axial soft tissue component. Preoperative correct imaging diagnosis is crucial to improving patient management.