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Temporary Blindness And Short-Term Vision Loss

You can temporarily lose your vision, totally or partially, due to another condition. The possible causes and what you should do depend on whether you can see at all.

If you have a sudden total, black-out, or near-total vision loss, it's an emergency. You need to call 911, because you have a short window of time to get it diagnosed and treated. Don't wait to see if it goes away.

If you have partial vision loss, a migraine is the most likely reason. But there are other, less common, causes that need prompt treatment to save your sight.

It can happen if a clot creates a blockage in your retinal artery. Your doctor may call it "central retinal artery occlusion" or "branch retinal artery occlusion." It also means you're at risk for a stroke or heart attack. It can happen if you get a blood clot that clogs a blood vessel in the eye. It's similar to how a clot can trigger a heart attack if plaque in your coronary arteries breaks off and forms a clot. If the same thing happened in your brain, it would be an "ischemic" (clot-triggered) stroke.

Clots can cause temporary blindness in one eye, usually lasting 20 to 30 minutes. It often seems like a curtain of darkness falls (doctors call this "amaurosis fugax"). Without prompt treatment, this blockage may cause permanent blindness.

Your doctor may prescribe a medicine to break up the clot. Some cases need angioplasty, a procedure to reopen the blockage in the blood vessel. And it's also a wake-up call to lower your risk of a heart attack or stroke.

As with a total vision loss, any temporary or partial vision loss needs to be checked out immediately in the emergency room. If you have partial vision loss, the causes could include:

Migraines: These are, by far, the most common cause of short-term, partial vision loss. When you get a migraine, you may have "aura" that affects the vision in both of your eyes. You may see flashing lights, shimmering spots, or blind spots.

A retinal migraine affects only one eye. This rare condition causes partial or total blindness for a short period, usually 10 to 30 minutes. It typically comes before or during a headache. It is typically harmless to you and your vision. 

Retinal vasospasm: Like migraine, this condition can cause temporary vision loss. Treatment can fully restore your sight.

When a blood vessel in your retina tightens, it causes a vasospasm. This cuts down on blood flow, which can bring on temporary vision loss in one eye. Various conditions can lead to a vasospasm. These include a retinal migraine, atherosclerosis, and high blood pressure.

If you have a retinal vasospasm, your doctor may recommend aspirin or a type of medicine called a calcium channel blocker to relieve it. You'll also work with your doctor to manage whatever caused the retinal vasospasm in the first place.

Closed-angle glaucoma: When your eye's iris bulges, it can prevent fluid from draining properly. This builds up pressure in your eye. You'd have a lot of discomfort, nausea, short-term blurred vision, halos, or blindness in one eye. Your doctor will look for a slightly enlarged pupil that doesn't react to light. Without prompt treatment, it can cause permanent blindness.

Medicines you take as an eyedrop or as a pill, such as prostaglandins or beta-blockers, can help ease the pressure in your eye. If that doesn't work, you may need an operation called an iridotomy. The surgeon makes a tiny hole in your iris, which lets the fluid drain and eases the pressure.

Giant cell arteritis: This condition isn't common, but it's an important cause of vision loss in people older than 50.

This disease causes inflammation in the linings of your arteries, particularly those in your head. Symptoms include head pain, scalp tenderness, jaw pain, fever, and fatigue. Giant cell arteritis also triggers vision loss, usually in one eye. Without treatment, it can result in permanent blindness in a week or two.

Your doctor will probably first give you a corticosteroid, such as prednisone. You'll likely feel better within a few days, but you may need to keep taking the drug for 1 or 2 years. A drug called tocilizumab (Actemra) is also approved to help treat giant cell arteritis.

These are very unlikely to be the cause of temporary vision loss.

Retinal vein occlusionis when a vein in the retina gets blocked, often due to a blood clot. It can lead to a buildup or leak of fluid in the eye, as well as swelling. Some people have bouts of temporary vision loss leading up to this condition. It's more likely to happen in people who have diabetes and health problems that affect blood flow, such as high blood pressure.

Your doctor may inject corticosteroids to control the inflammation. You may also need another type of drug called an anti-vascular endothelial growth factor or laser treatment to cut the fluid buildup.

Epileptic seizures: For about 5% to 10% of people with epilepsy, their seizures affect their occipital lobe, the part of the brain that controls vision. As a result, this disease can prompt vision loss during and after a seizure. If you have epilepsy, your doctor will recommend treatment to help prevent this and other complications.

Papilledema: This is a condition where pressure in the brain causes your optic nerve to swell. This can lead to vision changes, such as double vision, blurriness, and short-term blindness. It usually lasts for a few seconds. Other symptoms include headaches and vomiting. Papilledema may be the result of a tumor, abscess, or blood clot. High blood pressure, an infection, and certain medications can also put pressure on the brain.

Uhthoff phenomenon: This affects only people with multiple sclerosis (MS) -- and it's rare even among them. MS damages nerves, and it can make them more sensitive to heat. With Uhthoff phenomenon, a rise in your body temperature worsens your symptoms. It lasts less than a day. You can lose your vision in one or both eyes. You may also feel weaker, more numb, or dizzier than usual. Triggers for the condition include exercise, a fever, a hot bath, sun exposure, and stress. Your MS treatment should help prevent this and other complications.

What To Know About Flashes Of Light In The Corner Of The Eye

Seeing flashing lights in the corner of one or both eyes can occur with migraine or result from trauma, detached retina, or other problems. The flashes of light may vary in shape, color, frequency, and duration.

Flashes of light in the corner of the eye could be due to changes in the eye's structure, which becomes more common with age.

Some conditions, such as migraine auras, may also cause flashes of light in the eyes.

This article will examine the causes of flashes of light in the corner of the eye. It will also cover when a person should get advice from a doctor.

Flashes of light in the corner of the eye can result from an eye condition or injury. Photopsia is the medical name for these flashes, and this phenomenon usually occurs when there are changes inside the eye.

The retina is a thin layer of tissue that receives light at the back of the eye. It processes the light from the lens to send impulses through the optic nerve to the brain.

The vitreous body is a gel between the retina and lens that protects the retina and maintains the eye's structure.

Occasional flashes are usually harmless and may happen more with aging. However, visual disturbances can also result from eye trauma, such as a blow to the eye or rubbing the eye too hard, or a medical condition.

Seeing flashes of light is not usually a cause for concern. However, if this occurs regularly, a person should contact a doctor.

Sometimes, flashes of light in the eye could signal a severe problem. They may also appear alongside floaters, which are tiny dots or lines that may appear in a person's vision.

The combination of sudden, repeated flashes with other visual disturbances could indicate vitreous detachment or a more severe condition.

Some eye-related causes of flashes in the corner of the eye can include:

Vitreous body or retinal damage

Changes in the shape or position of the vitreous body are common and become more likely with age. A vitreous detachment can cause these flashes with floaters.

Vitreous detachment is a condition wherein the vitreous body breaks away from the retina. There are currently no treatments for vitreous detachment associated with aging, and people tend to adapt to the flashes and floaters eventually.

Vitreous detachment is not usually serious. However, it could have severe consequences, such as a hole or tear in the retina, for some people. Tearing the retina can cause retinal detachment or bleeding in the eye. The symptoms can also include blurred or darkened vision.

Cryotherapy and laser therapy are common and effective treatments for retinal tears. For some people, however, the tear causes no symptoms and requires no treatment.

Trauma

Eye trauma can also cause flashes in the corner of the eye. Trauma can put pressure on the retina, causing flashes.

Symptoms of eye trauma might disappear immediately and require no treatment. However, a person should contact a doctor immediately if they experience any of the following symptoms:

persistent eye pain

vision problems

cut or torn eyelids

difficulty moving the eye

a change in pupil size or eye position

blood in the eye

a feeling of something being stuck in the eye

A person should also avoid touching or scratching the eye.

Several other health conditions can cause flashes in the corner of the eye, such as:

Migraine

People with migraine commonly experience auras. An aura is a collection of sensory disturbances that indicate the start of a migraine episode. These disturbances may include:

visual disturbances, such as seeing flashes of light, spots, or zigzags

vision loss

sensory changes, such as tingling or numbness

difficulty speaking or understanding others

Combinations of medications that reduce the symptoms and prevent future episodes are available to treat migraine.

Occipital epilepsy

Occipital epilepsy is a rare condition that affects some young children and teenagers with epilepsy. It may cause seizures that affect vision, leading to the person seeing flashing lights and multicolored spots.

Most young children and teenagers stop having these seizures as they age.

Doctors may treat occipital epilepsy using antiepileptic drugs to prevent seizures.

Stickler syndrome

Stickler syndrome is a rare genetic condition that can cause problems with the eyes, hearing, and joints. Stickler syndrome also commonly causes distinct facial features, such as a small chin and cleft palate.

Stickler syndrome can also cause eye abnormalities that increase the risk of developing retinal detachment, leading to flashes and floaters.

There is currently no cure for Stickler syndrome, and treatment depends on the specific symptoms a person experiences. For example, if a person has a detached retina, doctors may recommend laser surgery, freezing treatment, or other surgery types.

Diagnosis for flashing lights in the eyes will include an eye examination. A doctor will ask the person about their symptoms and any possible causes, such as a recent blow to the eye.

If a patient presents with flashes and floaters, the doctor will almost always perform a dilated fundus exam. This test can check for many different eye conditions.

They will visually inspect the eye for any signs of injury, and they will also look out for distinctive features of someone with Stickler syndrome, such as a cleft palate.

An eye examination may include scleral depression, which involves applying gentle pressure to the eye. It may also involve using a specific lens for inspecting the retina.

Some people report anxiety causing vision problems that include seeing stars or shimmers. However, there has been little research into visual disturbances as a symptom of anxiety.

Flashes in the corner of the eye can have many causes. The flashing mostly results from changes in the eye's structure, which becomes more likely with age. Age-related eye changes are usually harmless.

However, some causes of seeing flashes in the eyes could be severe. For example, retinal tears can cause bleeding or persistent vision problems. Some conditions, such as migraine auras, can also cause flashes in the eyes.

Anyone experiencing continuous flashing in the eyes or flashing alongside other visual disturbances should contact a doctor.

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