Tentorial cavernous angioma with profuse bleeding. Case report.

This 15-year-old boy with a tentorial cavernous angioma reported occasional headache and scintillation in his left visual field. Magnetic resonance imaging revealed a well-demarcated, homogeneously enhanced tumor originating from the right cerebellar tentorium and extending into both the supratentorial and infratentorial spaces. Although a meningioma was suspected, vertebral artery angiography revealed a thickened meningeal branch originating from the right posterior inferior cerebellar artery and flecked tumor stain with pooling of contrast medium until the late venous phase. A cavernous angioma of the tentorium was suspected based on this finding, and as expected from the radiological findings, profuse bleeding was encountered during tumor removal. The histological diagnosis was a cavernous angioma. A cavernous angioma of the tentorium is extremely rare but should be differentiated from a meningioma preoperatively given that a cavernous angioma of dural origin tends to bleed massively during removal.