Absence of both internal carotid arteries.

A 63-year-old man developed a slight left hemiparesis. CT scan showed an intracerebral tumour, which was later identified as glioblastoma multiforme. Angiographic examination revealed the absence of both internal carotid arteries. Blood supply of anterior and middle cerebral arteries was provided by communication between a tortuous megadolichobasilar artery and the circle of Willis through enlarged posterior communicating arteries. The case is reported with reference to clinical symptoms as well as angiographic and anatomical findings of 17 comparable cases mentioned in literature.