Vision loss may be acute or gradual; gradual vision loss is caused by multiple processes, including cataracts, glaucoma, and atrophic age-related macular degeneration. Vision loss may also be partial or complete; partial vision loss presents as visual field defects and has a variety of manifestations and causes (see Table 1: Approach to the Ophthalmologic Patient: Types of Field Defects ).

Acute vision loss may be due to central retinal artery or vein occlusion (including artery occlusion caused by temporal arteritis), optic neuritis or neuropathy, vitreous hemorrhage, retinal detachment, neovascular age-related macular degeneration, stroke, or functional disorders (eg, hysterical conversion reactions or malingering). In some instances, acute vision loss may last only minutes to hours (amaurosis fugax); causes include ocular migraine, emboli to retinal arteries, and transient ischemic attacks.

Sudden, unilateral, painless complete vision loss suggests central retinal artery or vein occlusion, embolus, ischemic optic neuropathy, vitreous hemorrhage, retinal detachment, or optic neuritis, although optic neuritis may cause pain on eye movement. Painful loss may be due to acute closed-angle glaucoma, uveitis, or, rarely, corneal hydrops. A unilateral curtain or window shade being drawn down suggests retinal detachment or a progressive vasculature problem, such as branch retinal artery occlusion. Complex, continuous, shimmering or flashing lights (scintillating scotoma) or kaleidoscopic phenomena that obscure vision in both eyes but that clear after about 20 min suggest migraine headache. Bilateral visual field loss, sometimes with additional neurologic symptoms and duration of < 24 h, suggests a transient ischemic attack of the visual cortex.

The patient requires a complete ophthalmologic examination, including tests of visual acuity, peripheral vision and the presence and shape of any field defects, slit-lamp examination, and gonioscopy (if angle closure is suspected). A specific field defect can indicate the location of a visual pathway lesion (see Fig. 1: Approach to the Ophthalmologic Patient: Cross-section of the eye.). Flare and cells in the anterior chamber suggest uveitis; a swollen and opacified cornea suggests corneal hydrops; high intraocular pressure with a mid-dilated pupil suggests acute closed-angle glaucoma. On dilated fundus examination, localized retinal whitening suggests branch retinal vein occlusion; whitening of the entire retina suggests central retinal vein occlusion and may be accompanied by a macular cherry-red spot. A swollen optic nerve with or without surrounding flame-shaped hemorrhage signifies optic neuritis. Findings of vitreous hemorrhage or retinal detachment are diagnostic.

Additional testing may be necessary depending on examination findings; ESR should be performed to exclude temporal arteritis, and fluorescein angiography may be indicated to document retinal vein occlusion.

Treatment is management of the underlying condition.

Last full review/revision November 2005