فقدان مفاجئ وغير مؤلم للنظر: اعتلال العصب البصري الإقفاري

English version

Sudden Painless Vision Loss: Non-Arteritic Ischemic Optic Neuropathy

Quick answer

Non-arteritic anterior ischemic optic neuropathy (NAION) can cause sudden, painless vision loss in one eye when blood flow to part of the optic nerve is affected. Sudden vision loss is an emergency even without pain. A form linked to arteritis must also be ruled out, especially with a new headache or jaw pain while chewing.

What might someone notice?

A dark area or missing part of vision may appear over hours and is sometimes noticed on waking. It is usually painless, but that does not make it minor. Note when it began and seek emergency or urgent eye care rather than waiting for it to improve.

How is it different from optic neuritis?

Optic neuritis may cause pain with eye movement and altered color perception, while ischemic optic neuropathy often begins without pain. Symptoms can overlap, and other conditions also cause sudden vision loss, so one symptom or an online search cannot distinguish them.

Why does the doctor rule out arteritis?

In some people, especially over age 50, giant cell arteritis can cause vision loss and requires immediate treatment to protect the other eye and overall health. Tell the clinician about a new headache, scalp tenderness, jaw pain while chewing or unusual fatigue. Do not wait for every sign to appear.

Which tests may be needed?

The clinician checks visual acuity, pupils, visual field and optic nerve and may use OCT or other imaging. If arteritis is suspected, urgent blood tests and further assessment may be needed. The work-up depends on age, symptoms and the optic nerve appearance.

Treatment and follow-up

No treatment has been proven to reliably restore vision in every non-arteritic case. The clinician assesses health factors that may be associated with it, such as blood pressure, diabetes and sleep apnea, and coordinates follow-up with your doctors. Do not stop or change any medicine yourself; report new changes in the other eye.

Frequently asked questions

Does ischemic optic neuropathy cause pain?

Vision loss is often painless, but lack of pain does not reduce the need for urgent assessment.

Will vision return to normal?

Recovery varies and cannot be guaranteed. Early diagnosis is important to rule out other treatable causes.

Is this the same as optic neuritis?

No. They are different conditions, though some signs can overlap. Examination and imaging help identify the cause.

Should I stop blood pressure or diabetes medicines?

Do not stop or change medicines yourself. Discuss medications and health factors with your clinician.

This article is for education and does not replace an eye examination. Sudden vision change, severe pain, an eye injury or another emergency sign needs urgent assessment.