Double Oxymoron Crisis: Posterior Circulation Intracranial Bleeding with Anterior Circulation Ischemic Stroke—A Management Dilemma

Blood flow to the brain is mainly through anterior circulation via bilateral internal carotid arteries and through posterior circulation via bilateral vertebral arteries. The anterior circulation is for the respective side with the communication with the anterior communicating artery. The posterior flow is with the single basilar artery formed from vertebral arteries. There are collaterals present but the main vasculature determines most of the flow. This dynamic is normally balanced except in pathological conditions where flow is compensated from other vessels through the circle of Willis. It is rare to see a competing flow on each side and further, it is more complex when one region has a restricted flow and while another region has hyperdynamic