Arteritic anterior ischemic optic neuropathy
Sudden painless monocular vision loss from occlusion of the posterior ciliary artery by giant cell arteritis infarcts the optic nerve head and threatens the fellow eye within days. Treatment with high-dose glucocorticoids must begin on clinical suspicion, before biopsy confirmation, because established blindness is usually permanent.
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What this article covers
- Overview
A true ophthalmic and rheumatologic emergency: arteritic anterior ischemic optic neuropathy (AAION) is sudden, painless, usually monocular vision loss caused by giant cell arteritis (GCA) occluding…
- Epidemiology
Age: GCA, and therefore AAION, almost always affects patients older than 50 years, with peak incidence between 70 and 80 years.
- Risk factors
Age over 50 years: the dominant risk factor; incidence rises sharply with age and peaks in the eighth decade.
- Pathophysiology
Granulomatous panarteritis of large and medium vessels: CD4-positive T lymphocytes, macrophages, and multinucleated giant cells infiltrate the vessel wall, disrupting the internal elastic lamina.
- Clinical features
Sudden, painless, usually monocular vision loss: the hallmark presentation; loss may be preceded by transient episodes (amaurosis fugax) or reversible diplopia, warning signs demanding urgent evaluation before permanent loss occurs.
- Differential diagnosis
Non-arteritic AION (NAION): the most important same-category mimic; patients are often younger, have vasculopathic risk factors (diabetes, hypertension, hyperlipidemia, obstructive sleep apnea) and a…
- Diagnosis
The diagnostic framework is the American College of Rheumatology (ACR) classification criteria for GCA, 3 of 5 required: age of onset over 50 years; new-onset localized headache; temporal artery…
- Management
Start glucocorticoids immediately on suspicion; if there is acute or evolving visual loss, treat as follows: methylprednisolone 1 g IV once daily for 3 days, then transition to oral prednisone 1…
- Complications
Irreversible blindness, unilateral or bilateral; the affected eye typically does not regain vision, and the untreated fellow eye is at high risk within days to weeks.
- Prognosis
Prompt treatment is the single most important prognostic factor: the risk of blindness falls from about 15% untreated to about 1% with timely, adequately dosed corticosteroid therapy.
- Prevention
Treat empirically at first suspicion rather than waiting for confirmation: starting high-dose glucocorticoids before biopsy is what drops the blindness risk from about 15% to about 1%; this is the…
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