AION typically presents suddenly and upon awakening. The patient notes seeing poorly in one eye. Vision in that eye is obscured by a dark shadow, often involving just the upper or lower half of vision. There is no pain. There may be a slight improvement of visual acuity over the course of the next month, but generally, there is little change. There is a serious risk of a similar event occurring in the fellow eye over the next few years. Fortunately, it may not be terribly devastating as the visual acuity may remain only moderately impaired. Furthermore, most cases of AION involve the loss of a hemifield (either the upper or lower half of the visual field, but not both). A few cases of AION involve almost total loss of vision.

Since arteritic AION is similar in presentation to non-arteritic AION, patients over the age of 50 diagnosed with AION must be evaluated to exclude AAION (symptoms: painful jaw muscle spasms, scalp tenderness, unintentional weight loss, fatigue, myalgias and loss of appetite). Furthermore, AION patients over the age of 75 should often be blood tested regardless.