Acute Persistent Visual Loss: Ischemic Optic Neuropathy
What causes it?
In most cases, the cause is presumed to be hypoperfusion in vessels narrowed by arteriosclerosis. Patients may be untreated or overtreated hypertensives, or have suffered a sudden drop in blood pressure or acute blood loss. The hypoperfusion affects the ciliary blood supply of the optic nerve and causes optic disc infarction.
Visual loss is quick and painless. The optic disc is always swollen!
Giant cell arteritis is an urgent consideration in patients aged more than 65 years, especially if they have symptoms of polymyalgia rheumatica (limb girdle aches and weakness, anemia, anorexia, lethargy), headache, scalp tenderness, jaw claudication, and a high sedimentation rate.
Diagnosis of giant cell arteritis is based on finding inflammation on . It shows and sometimes .
What to do?
There is no treatment for non-arteritic ischemic optic neuropathy. Management is aimed at risk factor control.
If you suspect giant cell arteritis, promptly administer high dose corticosteroid treatment (1-2 gm/day intravenous methylprednisolone for 3-5 days) in order to prevent optic nerve infarction in the fellow eye.
Perform a temporal artery biopsy, harvesting at least 2 cm of vessel for the pathologist because the disease can skip large areas.
To learn more, go to Principal Ophthalmic Conditions: ischemic optic neuropathy.