Common Causes and Treatments of Sudden Loss of Vision

The sudden loss of one's vision is a frightening experience. Some causes of sudden, or acute, vision loss are reversible. Some forms of acute loss of vision are not reversible but treatment is required to prevent further loss of the visual field or loss of vision in the unaffected eye. A third subset of sudden vision loss results in permanent visual impairment.

Central Retinal Artery Occlusion:

Occlusion of the retinal artery causes sudden profound loss of vision in one eye. It is usually due to an embolus from a plaque in the internal carotid artery. If the vision loss lasts less than 24 hours this is called "amaurosis fugax" and the embolus is assumed to have passed through the retinal circulation with on irreversible consequences. If only a branch of the artery is occluded then the visual defect will be in the upper or lower half of the visual field.

Treatment of Central Retinal Artery Occlusion:

If symptoms have been present only 6 to 12 hours then an attempt to dislodge or dissolve the embolus should be made. Treatment to prevent further occurrences may involve treating heart arrhythmias, hypertension, carotid stenosis, and high cholesterol.

Central Retinal Vein Occlusion:

Occlusion of the central retinal vein causes visual loss that is not pas rofound as that which occurs with retinal artery occlusion. Loss of visual acuity with central retinal vein occlusion is sudden but generalized, unless only a branch is affected. If a branch is affected only the corresponding part of the visual field is affected.

Treatment of Central Retinal Vein Occlusion:

Any risk factors that may have precipitated the vein occlusion need to be identified and treated. These may include hypertension, diabetes and hyperviscosity syndromes. Laser treatment is sometimes helpful for central retinal vein occlusion.

Optic Neuritis:

Optic neuritis is inflammation of the optic nerve. Demyelination of the optic nerve causes painful, unilateral vision loss often with partial resolution of sight. Visual acuity is at its worst within one week. Other symptoms of optic neuritis include headache and eye pain with eye movement. Many individuals with optic neuritis have multiple sclerosis or will eventually progress to multiple sclerosis.

Treatment of Optic Neuritis:

Steroids such as prednisone may help quicken recovery from optic neuritis. Optimal treatment of multiple sclerosis is necessary to prevent recurrent episodes of optic neuritis that may result in permanent blindness.

Atherosclerotic Ischemic Optic Neuropathy:

Ischemic optic neuropathy is caused by an infarction (obstruction of blood supply) of the optic nerve head in the eye. It usually affects patients over 60 years of age. These individuals are likely to have other evidence of vascular disease such as angina (chest pain with exertion) or intermittent claudication (leg pain with exertion).

Anterior ischemic optic neuropathy begins with rapid, painless loss of vision in the affected eye. In some individuals the vision loss is only in the upper or lower fields of vision.

Treatment of Atherosclerotic Ischemic Optic Neuropathy:

Unfortunately, there is no treatment for this condition. Visual recovery does not occur.

Arteritic Ischemic Optic Neuropathy:

This is most commonly due to giant cell arteritis, also called temporal arteritis. Temporal arteritis is similar to atherosclerotic optic neuropathy in that it presents with rapid, painless loss of vision in the affected eye that may be in only the upper or lower fields of vision.

However, temporal arteritis is a systemic disorder and patients may also have general malaise, headaches, thickened, tender temporal arteries, pulsating temporal artery, scalp tenderness, muscle tenderness and jaw claudication (pain or weakness when chewing). More than 50% of patients with temporal arteritis have polymylagia rheumatica. Individuals with giant cell arteritis usually have evidence of inflammation such as an elevated ESR or CRP level.

Treatment of Arteritic Ischemic Optic Neuropathy

It is important to see a physician immediately because giant cell or temporal arteritis is treatable. High doses of steroids such as prednisone are used to preserve the vision in the other eye which has a 65% chance of being affected within 10 days. Steroid treatment may be required for many years.

Vitreous Hemorrhage:

Symptoms of vitreous hemorrhage may initially include floaters, which can quickly progress to vision loss. These visual symptoms are due to bleeding into the vitreous humor. Common causes of vitreous hemorrhage are diabetic retinopathy and retinal tears following trauma to the eye or head. Subarachnoid hemorrhage may also cause vitreous hemorrhage.

Treatment of Vitreous Hemorrhage:

The treatment of vitreous hemorrhage may include photocoagulation laser treatment or vitrectomy.

There are many different causes of sudden loss of vision. The return of vision or partial or permanent loss of vision depends upon the cause and the rapidity of treatment initiation. Any decrease in vision should be immediately investigated by a physician or eye doctor.