Brain vascular malformations, including arteriovenous malformations (AVM), cavernous malformations (CVM) and aneurysms, are a source of life-threatening risk of intracranial hemorrhage. The etiology and pathogenesis are unknown. There is no medical therapy presently available. Prevention of spontaneous intracerebral hemorrhage (ICH) is the primary reason to treat brain vascular malformations. The goal of this study is to: begin pilot studies to lay the groundwork for future clinical trials to develop medical therapy to decrease ICH risk.