Causes of Sudden Vision Loss
The retina is a thin layer of tissue at the back of the eye. It captures light and sends signals to the brain so you can see. When the retina pulls away from its normal position, this is called a retinal detachment. It can happen quickly and without pain.
Warning signs include a sudden increase in floaters, which are small dark spots or lines that drift across your vision. You may also see flashes of light or a shadow moving across your field of vision. Retinal detachment does not get better on its own. Without treatment, it can lead to serious vision loss. If you notice these symptoms, contact our office right away. Risk factors include severe nearsightedness, prior eye surgery, and eye trauma.
A retinal artery occlusion happens when a blood clot blocks one of the arteries that supply blood to the retina. This cuts off the oxygen supply and can cause sudden, painless vision loss in one eye. Treatment is most effective when it begins within the first few hours, making this one of the most time-sensitive eye emergencies.
A retinal vein occlusion occurs when a vein that drains blood from the retina becomes blocked. This leads to bleeding and swelling inside the eye. Both types are more common in people with high blood pressure, diabetes, high cholesterol, or heart disease. Smoking also raises the risk.
A vitreous hemorrhage is bleeding into the gel-like substance that fills the inside of the eye. When blood enters this space, it blocks light from reaching the retina. You may notice a sudden shower of floaters, hazy or reddish vision, or a drop in clarity. Common causes include diabetic eye disease, a torn retina, or trauma.
Acute angle-closure glaucoma happens when the drainage system inside the eye becomes blocked, causing a rapid buildup of pressure. Symptoms include sudden blurry vision, severe eye pain, headache, nausea, and seeing halos around lights. The eye may appear red. This is a medical emergency because the high pressure can damage the optic nerve within hours.
Optic neuritis is inflammation of the optic nerve, which carries visual signals from the eye to the brain. It can cause sudden vision loss in one eye, pain with eye movement, and changes in color vision. It is most common in younger adults and is sometimes linked to multiple sclerosis.
Giant cell arteritis causes swelling in the blood vessels of the head and neck. It most often affects people over the age of 50. It can reduce blood flow to the optic nerve and cause sudden, severe vision loss. Other symptoms may include a new headache, tenderness near the temples, and jaw pain while chewing. Without treatment, vision loss can spread to the other eye within days or weeks.
A stroke can also cause sudden vision changes. When blood flow to the part of the brain that processes vision is interrupted, you may lose vision in one or both eyes. According to the National Eye Institute in 2022, stroke is among the leading causes of sudden visual field loss in older adults. Call emergency services right away if you suspect a stroke.
Treatments for Sudden Vision Loss
Laser treatment is used for several conditions that cause sudden vision loss. For retinal tears that may lead to detachment, a laser can seal the tear and help prevent further separation. Laser therapy is also used to treat areas of the retina damaged by vein occlusions. The procedure is done in the office and takes only a few minutes.
Intravitreal injections deliver medication directly into the eye. These injections are a common treatment for retinal vein occlusions and other conditions that cause retinal swelling. The medication helps reduce fluid buildup and may improve vision over time. Your provider will numb the eye before the injection. A series of injections may be needed over several weeks or months.
Retinal detachment often needs a procedure called a vitrectomy. The gel inside the eye is removed and replaced with a gas bubble or silicone oil to push the retina back into place. Another option is a scleral buckle, which places a band around the outside of the eye to press the wall against the detached retina. Your provider will recommend the approach that fits your situation.
For vitreous hemorrhage that does not clear on its own, a vitrectomy can remove the blood and restore clear vision. Surgery for acute angle-closure glaucoma may involve a laser procedure called an iridotomy, which creates a small opening in the iris to improve fluid drainage and lower eye pressure.
Giant cell arteritis is treated with high-dose steroid medication, usually started right away to reduce inflammation and protect vision in the other eye. Your provider will work with your primary care doctor or a rheumatologist to manage this treatment, as steroids are typically needed for many months.
Optic neuritis may be treated with intravenous steroids to speed recovery, followed by oral medication. Stroke-related vision loss is managed by a hospital team, with treatment focused on restoring blood flow to the brain. After the initial emergency, our team can help evaluate and manage any lasting effects on your vision.
What to Expect During Your Visit
When you arrive at Washington Eye Institute with sudden vision loss, our team will begin your evaluation promptly. You will be asked about when your symptoms started, which eye is affected, and whether you have pain. Your medical history and current medications are also important. If you have severe symptoms such as a sudden headache, nausea, or loss of vision in both eyes, let our staff know right away.
Your provider will measure your visual acuity to check how much vision has been affected. Eye pressure will be tested, and a preliminary examination of the front of the eye will be done using a slit lamp microscope.
A dilated eye exam is one of the most important steps in evaluating sudden vision loss. Your provider will place drops in your eye to widen the pupil. This allows a clear view of the retina, optic nerve, and blood vessels inside the eye. The drops take about 20 to 30 minutes to work. Your vision will be blurry for a few hours afterward, so plan to have someone drive you.
Optical coherence tomography, known as OCT, uses light waves to create detailed images of the retina. This painless scan can reveal swelling, fluid buildup, or structural changes. Fluorescein angiography is another test your provider may use. A yellow dye is injected into a vein in your arm. As the dye travels through the blood vessels in your eye, a camera takes photographs that show blockages, leaking vessels, or abnormal growth.
After testing is complete, your provider will review the results with you. You will receive a clear explanation of what is causing your vision loss and what treatment options are available. If your condition requires same-day treatment, your provider will discuss the procedure and answer your questions before proceeding. If monitoring is needed, you will be given a follow-up plan with instructions on what to watch for at home.
Your Care Journey at Washington Eye Institute
If you experience sudden vision loss, call our office right away. Let our staff know you are having an emergency so they can prepare for your arrival. Our Greenbelt, Rockville, and Cumberland locations are equipped to handle urgent eye conditions. If your symptoms include sudden headache, weakness on one side of the body, or difficulty speaking along with vision changes, call 911 first, as these may be signs of a stroke.
When you arrive, bring a list of your current medications and any relevant medical records. If you wear glasses or contact lenses, bring those as well. Having someone with you is helpful, since your eyes may be dilated during the visit and your vision will be blurry for several hours.
Your treatment plan will depend on the cause and severity of your vision loss. Some conditions, like retinal detachment, may require same-day surgery. Others, like a mild vitreous hemorrhage, may be monitored over several weeks. Your provider will explain the expected timeline for your recovery.
Follow-up appointments are an important part of your care. During these visits, your provider will check your vision, examine the inside of your eye, and adjust your treatment if needed. Our fellowship-trained specialists will be with you through each stage of recovery.
After the initial emergency has been treated, your provider may recommend regular eye exams to monitor for changes. Many conditions that cause sudden vision loss are connected to broader health issues like high blood pressure, diabetes, or inflammation. Managing these underlying conditions can reduce the risk of future episodes.
Attend all scheduled follow-up appointments, take your medications as directed, and report any new symptoms right away. If you notice new floaters, flashes of light, a shadow in your vision, or any sudden change in how well you can see, contact Washington Eye Institute without delay.
Questions and Answers
Any sudden change in vision should be treated as urgent. If you lose vision in one or both eyes without warning, see flashes of light, notice a sudden increase in floaters, or experience a shadow across your visual field, seek care right away. Severe eye pain, nausea, or headache along with vision changes also signal a possible emergency. Do not wait to see if the symptoms go away on their own. Early treatment can make a significant difference in the outcome.
In many cases, treatment can improve or partially restore vision that has been lost suddenly. The outcome depends on the cause, the severity, and how quickly treatment begins. A retinal detachment that is repaired promptly often results in meaningful vision recovery. A retinal artery occlusion may have a more limited recovery because the retina can be damaged quickly when its blood supply is cut off. Your provider will give you an honest assessment based on your situation.
A retinal artery occlusion is a blockage in an artery that brings oxygen-rich blood to the retina. It causes sudden, significant painless vision loss and is one of the most urgent eye emergencies. A retinal vein occlusion is a blockage in a vein that carries blood away from the retina. It causes bleeding and swelling that can lead to blurry or distorted vision. Both are linked to cardiovascular risk factors like high blood pressure and diabetes.
Not all types of sudden vision loss require surgery. Some conditions can be treated with medications, laser therapy, or injections. Retinal vein occlusions are often managed with intravitreal injections. However, conditions like retinal detachment and severe vitreous hemorrhage typically do require surgery. Your provider will explain whether surgery is recommended, what the procedure involves, and what to expect during recovery.
Recovery time varies depending on the condition and treatment. After laser treatment for a retinal tear, most patients return to normal activities within a day or two. Recovery from a vitrectomy for retinal detachment may take several weeks, and you may need to hold your head in a specific position to allow the gas bubble to support the retina. Injections for vein occlusions are given over months, with gradual improvement between treatments. Your provider will give you a timeline for your situation.
If you experience sudden vision loss after regular office hours, call our main phone number, as there may be an on-call provider available to guide you. If you cannot reach our office or if your symptoms include signs of a stroke such as sudden weakness, difficulty speaking, or severe headache, call 911 or go to the nearest emergency room. Let the staff know you are having vision loss so they can contact an eye specialist. Once stabilized, follow up with our team at the Greenbelt, Rockville, or Cumberland office.