An amazing case of head and neck CTA showing left internal carotid artery dissection with multiple pseudoaneurysms. An aneurysm is a localized, blood-filled balloon-like bulge in the wall of a blood vessel. Aneurysms can occur in any blood vessel, with particularly lethal examples including aneurysms of the Circle of Willis in the brain, aortic aneurysms affecting the thoracic aorta, and abdominal aortic aneurysms. | Dr. Muhammed Ziya