Anterior Ischemic Optic Neuropathy (AION) is a condition that occurs when blood flow to the optic nerve is reduced, leading to vision loss. This can happen due to various factors, including high blood pressure, diabetes, or other vascular issues. AION is often characterized by sudden vision loss in one eye, which may be accompanied by a visual field defect. There are two main types of AION: non-arteritic AION and arteritic AION. Non-arteritic AION is more common and typically affects older adults, while arteritic AION is associated with giant cell arteritis and can lead to more severe complications. Early diagnosis and treatment are essential for managing the condition.