In central retinal artery occlusion (CRAO), the typical patient experiences a sudden painless monocular loss of vision, either segmental or complete. Visual acuity may range from finger counting or light perception to complete blindness. Fundal findings may include the following: fundal paleness caused by retinal edema (the fovea does not have the edema and thus appears as a cherry-red spot); narrow and irregular retinal arterioles; and a “boxcar” appearance of the retinal venules.
Management and Disposition
Attempts to restore retinal blood flow may be beneficial if performed in a very narrow time window after the acute event. This may be accomplished by (1) decreasing intraocular pressure (IOP) with topical β-blocker eye drops or intravenous acetazolamide; or (2) ocular massage, applied with cyclic pressure on the globe for 10 seconds, followed by release and then repeated. Urgent consultation with an ophthalmologist is indicated to determine if more aggressive acute therapy (paracentesis) is warranted. However, such aggressive treatment rarely alters the poor prognosis. Medical evaluation and treatment of associated findings may be warranted. Tissue plasminogen activator may be considered for lysis of an occluding thrombus.
Visual decrement may be caused by a “low-flow” state (vs total occlusion). As this cannot be identified on presentation and can present hours later, immediate treatment and consultation are indicated regardless of the time of onset.
Sudden, painless monocular vision loss is typical.
CRAO may be associated with temporal arteritis. This diagnosis should be strongly considered in all patients presenting with signs and symptoms of CRAO who are older than 55 years.
Central Retinal Artery Occlusion. The retinal pallor caused by retinal edema is well demonstrated, contrasting with the “cherry-red spot” of the nonedematous fovea. Note the vascular narrowing and the “boxcar” appearance of the venules. (Photo contributor: Aaron Sobol, MD.)
Central Retinal Artery Occlusion with Cilioretinal Artery Sparing. “Hyperemia” of the fundus on the temporal side of the disk and sparing of the macular region owing to the presence of a patent cilioretinal artery. (Photo contributor: Thomas R. Hedges III, MD.)
Cilioretinal Artery Occlusion. Absence of blood flow with “boxcar” appearance is seen against a backdrop of retinal ischemia (whitening) in this branch occlusion. The remainder of the retina appears normal. (Used with permission from The University of Iowa and EyeRounds.org.)
Branch Central Retinal Artery Occlusion. Retinal whitening (owing to ischemia) and absence of blood flow in the inferotemporal branch retinal arteriole. (Photo contributor: Arun D. Singh, MD.)