The CT findings of cerebral arterial ectasia in 8 patients, of which 5 cases were angiographically documented, are reported. The ectatic arteries, located predominantly in the suprasellar and interpeduncular cisterns, appeared as serpiginous, tubular structures on the unenhanced scan. The enhanced CT scan demonstrated dense, sharply defined, homogeneous intraluminal enhancement. Until recently, the diagnosis of cerebral arterial ectasiawas usually established by angiography. with introduction of CT it has become possible to noninvasively indentify and characterized this vascualr disorder and its associated intracranial complications. The vertebrobasilardolichoectasia may be diagnosed by CT as an extra-axial lesion in the cerebellopontine angle. It enhances in atubular fashion after intravenous injection of contrast.