Anterior uveitis (iritis) accounts for the vast majority of uveitis seen in primary care. It usually, but not always, affects only one eye.

Blepharitis is common in both men and women, and affects all age groups including children. It is particularly common amongst post-menopausal women, which might point to the role of oestrogen in tear formation.

GCA is an important condition because it can cause profound, bilateral, and irreversible blindness. Blindness is due to involvement of the ophthalmic artery and resultant infarction of the optic nerves.