With nonarteritic anterior ischemic optic neuropathy (NAION) — the most common form of ION — the symptoms are usually sudden, painless vision loss in one eye, with your vision perhaps appearing cloudy or blurry. Usually these symptoms are noticed first when you wake up.

With arteritic AOIN, the more dangerous form of AION, the majority of people have giant cell arteritis (GCA). This condition may cause symptoms before vision loss, such as overall fatigue, fever, pain in the temples, neck pain, pain when chewing, and scalp pain. (Another less common form of GCA has no symptoms). A key visual symptom with arteritic AION is temporary blurring or loss of vision before vision loss is permanent.

Pop needs to be configured.