optic nerve disease anterior ischemic optic neuropathy Anterior ischemic optic neuropathy (AION) is an eye disease characterized by infarction of the optic disk leading to vision loss. It can be nonarteritic (nonarteritic anterior ischemic optic neuropathy or NAION) or arteritic, the latter being associated with giant cell arteritis (GCA; often termed temporal arteritis). Vision loss with both varieties is typically rapid (over minutes, hours, or days) and painless. Symptoms such as a general feeling of being unwell (malaise), muscle aches and pains, headaches over the temple, pain when combing hair, pain in the jaw after chewing, and tenderness over the temporal artery (one of the major arteries of the head) may be present with giant cell arteritis. At exam, visual acuity is reduced and the optic disc is swollen. In both subtypes, visual field examination is often reduced in the inferior and central visual fields. The visual loss is usually permanent, with some recovery possibly occurring within the first weeks or months. The arteritic variety is treated with corticosteroids. Treatment of the nonarteritic variety withaspirinor corticosteroids has not been helpful. COHD:373487 DOID:12010 EFO:1000809 GARD:0009790 ICD10:H47.01 ICD9:377.41 MESH:D018917 MONDO:0006649 MedDRA:10068250 SCTID:404659001 UMLS:C0155305 aion https://rarediseases.info.nih.gov/diseases/9790/anterior-ischemic-optic-neuropathy ischemic optic neuropathy optic disc infarction leading to vision loss