Sudden Loss of vision
What is Sudden loss of vision?
Sudden loss of vision is a medical emergency and should warrant one to visit their nearest optometrist or eye-care professional right away for a prompt examination.
Loss of vision is considered sudden if it develops over a couple of minutes to a couple of days. Sudden loss of vision could affect one or both eyes, and all or a part of one’s field of vision. If you experience loss of only a small part of the field of vision, it could present as blurred vision. Sudden loss of vision could be accompanied by other symptoms such as eye pain depending on the cause of the vision loss.
Sudden loss of vision is most often due to three general causes:
- Clouding of normally transparent eye structures
- Abnormalities of the retina (light-sensing structure at the back of the eye)
- Abnormalities of the nerves carrying visual signals from the eye to the brain (optic nerve and visual pathways)
In order to see, light must be able to travel through several transparent structures before being sensed by the retina. Light passes through the cornea, the lens, and the vitreous humor before reaching the retina. If there is something that blocks the light from passing through these structures, or disrupts the transmission of nerve impulses from the back of the eye to the brain, vision loss can occur.
There could be either a physical or neurological explanation for sudden vision loss. If vision loss is painless and due to a physical blockage, it may be caused by:
- Blockage of major artery of the retina
- Blockage of artery to optic nerve
- Blockage of major vein in retina
- Blood in the vitreous humor near the back of the eye (vitreous hemorrhage)
- Eye injury
A sudden retinal artery blockage could be due to a blood clot or small piece of atherosclerotic material that has broken off and traveled into the artery. The artery to the optic nerve could be blocked for the same reason, or due to inflammation. A blood clot could also form in and block the retinal vein, which is usually found in older people with high blood pressure or diabetes. Diabetes is also a risk factor for bleeding into the vitreous humor.
However, vision loss could be due to a less common cause, such as stroke, transient ischemic attack, acute glaucoma, retinal detachment, inflammation of the structures between the cornea and the lens (anterior uveitis, or iritis), infections of the retina, or bleeding within the retina as a complication of macular degeneration.
Your optometrist will conduct an exam and determine whether there is a physical or neurological cause for your vision loss and refer you to the proper specialist for further care if necessary. Depending on the cause of the loss of vision, immediate treatment could prevent further vision loss and if occurring in only one eye, trigger precautionary measures to decrease the risk of vision loss in the other eye.
If you experience a sudden loss of vision, you should see an ophthalmologist, optometrist, or visit the emergency room immediately. Loss of vision can indicate a serious vision and even life-threatening condition and should not be ignored or delayed.
