Internal Carotid Artery

The internal carotid artery (ICA) is one of the principal arteries supplying the brain. Intracranially, it gives important branches including the ophthalmic, posterior communicating and anterior choroidal arteries, before terminating as the anterior and middle cerebral arteries. Together, the right and left internal carotid arteries form the major anterior circulation of the brain and contribute to the Circle of Willis, providing blood to most of the cerebral hemispheres. ICA thrombosis, dissection or occlusion can produce extensive cerebral ischaemia and stroke. Traumatic carotid dissection may follow blunt neck trauma, hyperextension or rotational injury and can result in delayed cerebral infarction. Intracranial ICA aneurysms may rupture and cause subarachnoid haemorrhage.