BACKGROUND : Surgeries for deep and eloquent cerebral lesions require a detailed knowledge of normal brain anatomy and accurate planning. Important parts of brain anatomy are the cerebral blood supply and collateral circulation system. In addition to well-known cortical and basal (circle of Willis) anastomoses, there is also a deep interarterial anastomotic circle that is not described in the literature. METHODS : Twenty brain specimens were studied for deep arterial anastomotic connections between branches of the anterior and posterior choroidal arteries. RESULTS : We have marked 3 symmetric zones of deep arterial anastomoses that form an epithalamic circle. CONCLUSIONS : Epithalamic anastomoses provide an additional mechanism of blood distribution that may play a role during surgical interventions or stroke.