Anterior Ischemic Optic Neuropathy (AION) is a condition that causes sudden vision loss, often in one eye. Synonyms for this term might include anterior optic neuropathy, ischemic optic neuropathy, and optic nerve ischemia. Other variations on the terminology might include those that indicate specific causes of the condition, such as non-arteritic anterior ischemic optic neuropathy (NAION) or arteritic anterior ischemic optic neuropathy (AAION), which are differentiated by whether they are caused by reduced blood flow due to a blockage in the optic nerve or inflammation of the blood vessels, respectively. Regardless of the specific terminology used, it is important to seek medical attention immediately if sudden vision loss occurs, as prompt treatment can improve outcomes.