[CT and MR imaging findings in a case of cerebral alveolar echinococcosis masquerading as brain tumor].

We report a rare case of cerebral alveolar echinococcosis that was verified by pathological examination. The lesion presented as an intracranial mass which was slightly hyperdense on CT scans and very hypointense with central hyperintensity on T2-weighted MR images. The lesion exhibited marked contrast enhancement on both CT and MR images and was accompanied by extensive white matter edema. Although radiological differentiation from brain tumor was difficult, hypointensity on T2-weighted MR images appeared to be characteristic of lesions of cerebral alveolar echinococcosis.