INTRACRANIAL ARTERIAL CALCIFICATION AND ECTASIA IN VISUAL FAILURE

Calcification of the major intracranial arteries is frequently observe d on computed tomography (CT), particularly in the carotid siphon, and has been implicated as a causative factor in low tension glaucoma. Ec tasia of the carotid siphon has also been postulated as a possible cau se of compressive optic neuropathy. 153 patients, in whom high resolut ion CT of the orbits and parasellar region had been performed for susp ected anterior visual pathway pathology, were retrospectively reviewed . The presence and severity of calcification and ectasia of the major intracranial arteries was recorded. There was a high occurence of caro tid siphon calcification, increasing with age, and independent of sex or race. Calcification was very rare in anterior cerebral, middle cere bral and basilar arteries in all age groups. The amount and degree of ectasia also increased with advancing age, and was more frequently obs erved in carotid and basilar than anterior and middle cerebral arterie s. There was no correlation between the degree of calcification or ect asia and ophthalmological or neurological deficit.