MR imaging of intracranial cysticercosis: comparison with CT and anatomopathologic features.

Eight patients with neurocysticercosis were studied with CT and magnetic resonance (MR) imaging. Two cysts were shown better with MR than with CT. A conspicuous, high-intensity mural nodule containing the scolex allowed specific identification of intraventricular and parenchymal cysticerci. CT evidence of calcification and metrizamide enhancement in the nodule was also noted in one case. Racemose cysts were seen in the cerebellopontine angle and under the anterior septum pellucidum. Fluid in apparently live cysticerci and in racemose cysts had MR signal properties closely paralleling CSF. A thin subependymal or subpial rim of high signal intensity around the intraventricular and one of the racemose cysts was consistent with tissue reaction and aided diagnosis. While MR showed only one of numerous calcifications, it may be more sensitive than CT in the recognition of perifocal edema and of parenchymal and subarachnoid cysts, may replace invasive ventriculography in the diagnosis of intraventricular cysts, and may be useful in determining the viability of cysts and their response to therapy.