Cerebellar Arteriovenous Malformation with Coexistent Hemangioblastoma.

A case of a 40-year-old male with past medical history of smoking, hypertension, polycythemia vera, intellectual disability and schizophrenia who presented with generalized headaches, progressive loss of balance and visual disturbance for one month.Head CT and MRI revealed a right cerebellar hematoma associated to heterogenous lesion with cystic components and flow-voids in the right cerebellar hemisphere. Ventriculo-peritoneal shunt was placed with partial improvement of symptoms. Further vascular studies confirmed presence of a vascular nidus with significant arteriovenous shunting. Required later intervention for cerebellar arteriovenous malformation removal. Microscopic evaluation of the lesion showed the AVM nidus as well as large, vacuolated stromal cells and numerous thin-walled vessels. Immunostaining with inhibin and S-100 highlighted the stromal cells with numerous lipid-containing vacuoles. The above findings were consistent with the diagnosis of an arteriovenous malformation with coexistent hemangioblastoma of the right cerebellar hemisphere.Coexistence of hemangioblastomas and arteriovenous malformations is extremely rare, only three cases have been reported previously in the literature.