OPTIC NERVE DISEASES
Anterior Ischemic Optic Neuropathy
Anterior ischemic optic neuropathy is an ischemic damage of the optic nerve head. It is characterized by a painless unilateral visual loss, developing over a period of hours to days. Relative afferent pupillary defect is usually present, unless there is bilateral optic neuropathy. A visual field defect is usually found, most commonly altitudinal or arcuate.
An important distinction must be made between two clinical pictures that have different therapeutic and prognostic implication: arteritic anterior ischemic optic neuropathy (AAION) and non-arteritic anterior ischemic optic neuropathy (NAION).
AAION is the less frequent of the two entities, corresponding to 5-10% of the cases of AION. It is a serious condition corresponding to the occlusion of the short posterior cilliary arteries by an inflammatory process....