Thalamomesencephalic ossified cavernoma presenting with Holmes' tremor.

Background: Midbrain cavernoma associated with Holmes' tremor is a rare entity. Although there have been 4 other cases of Holmes' tremor caused by a cavernoma, this is the first case that was cured by surgical removal of the cavernoma. In addition, heavy ossification and Holmes tremor as a clinical presentation are 2 unusual features of the cavernoma. Possible mechanisms of these very rare entities are discussed in relation to the present report and relevant literature is reviewed.

Case Description: We present a case of 60-year-old woman with heavily ossified cavernoma of the thalamomesencephalic junction with neuroimaging and histologic features. The only manifestation was Holmes' tremor. The patient was operated on via posterior interhemispheric approach while in the sitting position. After the arachnoid folds of the quadrigeminal cistern were opened, the thin neural tissue on the surface of the dorsal midbrain was incised and the lesion was visualized and totally removed as a single piece. The tremor was almost completely suppressed.

Conclusion: Ossified cavernoma is a rare entity but has a characteristic MRI appearance. It should be considered in the differential diagnosis of intracerebral hypointense lesions on both T1- and T2-weighted MR images because they are potentially curable by surgical removal.