Eye Floaters and Flashes
When Floaters and Flashes Are an Emergency
A sudden burst of new floaters, a sudden increase in flashes of light, or a dark curtain or shadow moving across your vision can signal a retinal tear or detachment. According to the AAO, these symptoms require immediate evaluation by an eye doctor or emergency room. Retinal detachment is a medical emergency that can cause permanent vision loss without prompt surgical treatment.
The difference between normal floaters and an emergency is the word sudden. If you have had a few small floaters for years, that is common. If you see a shower of new spots, a burst of flashes, or a shadow in your side vision that was not there before, seek care the same day.
Call your eye doctor right away or go to an emergency room if you cannot reach them. Do not wait to see if the symptoms improve on their own. According to the NEI, retinal detachment can lead to permanent vision loss or blindness without prompt surgical treatment.
While waiting to be seen, avoid heavy lifting, bending, or jarring movements that could worsen a retinal tear. Note which eye is affected and when the symptoms started, since your doctor will ask for these details during your evaluation.
A retinal tear caught early can be sealed with a laser or freezing procedure in the office, preventing a full detachment. Once the retina detaches, surgery becomes necessary and the visual outcome depends on how much of the retina was affected and how long it was detached.
Patients who receive treatment within the first 24 to 48 hours of a retinal detachment have a better chance of recovering their vision. Delays of days or weeks reduce the likelihood of a full recovery, if the central retina (macula) detaches.
Common Causes of Floaters and Flashes
The most common cause of new floaters in adults over 50 is posterior vitreous detachment (PVD). The vitreous is a gel-like substance that fills the inside of your eye. As you age, this gel shrinks and pulls away from the retina. During this process, clumps of vitreous fibers cast shadows on the retina that you see as floaters.
According to the AAO, PVD also causes flashes of light when the vitreous tugs on the retina as it separates. PVD itself is not dangerous, but the pulling force can tear the retina. Your eye doctor performs a dilated exam to check for tears whenever you report new floaters or flashes.
Floaters can appear at any age, but they become more common as you get older. The vitreous gel breaks down over time, forming small clumps and strands that float through your field of vision. You may notice them most when looking at a bright sky, a white wall, or a computer screen.
These age-related floaters are annoying but not dangerous. They tend to settle below your line of sight over weeks to months. Your brain also adapts to ignore them over time, which is why older floaters bother you less than new ones.
According to the AAO, risk factors for PVD and floaters include age over 50, high myopia (nearsightedness), prior eye surgery, and eye trauma. Nearsighted people tend to develop PVD earlier because their eyes are longer, which puts more tension on the vitreous as it shrinks.
If you have had a PVD in one eye, you are more to develop one in the other eye within a few years. Cataract surgery also increases the likelihood of PVD because removing the lens changes the dynamics of the vitreous gel. Mention these risk factors to your eye doctor so they can monitor you appropriately.
Diagnosis and Treatment
Your eye doctor dilates your pupils and examines the entire retina with a bright light and magnifying lenses. This exam checks for retinal tears, holes, areas of thinning, and detachment. Your doctor may also use an ultrasound if the vitreous is too cloudy to see through with standard instruments.
A single exam may not be enough. Your doctor may ask you to return for a follow-up exam in 4 to 6 weeks to confirm that no tear has developed, since tears can form days to weeks after a PVD begins. Follow through with this appointment even if your symptoms improve.
Most floaters do not need treatment. According to the AAO, they become less noticeable over time as they settle in the eye and your brain learns to filter them out. Moving your eyes up and down or side to side can shift a floater out of your direct line of sight when it becomes distracting.
If floaters interfere with your daily tasks despite these strategies, mention it to your eye doctor. In rare cases, the number or size of floaters makes reading, driving, or screen work difficult. Your doctor can discuss whether intervention is appropriate for your situation.
Vitrectomy is a surgical procedure that removes the vitreous gel (and its floaters) and replaces it with a clear saline solution. This procedure carries risks including cataracts, retinal tears, and infection. Doctors reserve it for patients whose floaters cause major functional limitations.
Laser vitreolysis uses focused laser pulses to break up large floaters into smaller pieces. This office-based procedure is less invasive than vitrectomy but does not work for all types of floaters. Your doctor evaluates the size, location, and composition of your floaters to determine if laser treatment is an option.
Floaters and Flashes Questions
Floaters do not disappear, but they become less noticeable over time. The floaters settle lower in the eye and your brain adapts to ignore them. Most people find that new floaters bother them much less after a few months.
Floaters themselves do not cause blindness. However, a sudden onset of floaters can signal a retinal tear or detachment, which can cause permanent vision loss if not treated quickly. That is why any sudden change in floaters warrants an urgent eye exam.
Occasional flashes when you move your eyes in a dark room can happen during a PVD and may be normal. Frequent or persistent flashes, with new floaters, need evaluation. Your eye doctor can determine whether the flashes are from harmless vitreous traction or a retinal tear.
If you cannot reach your eye doctor the same day, go to an emergency room. A sudden shower of new floaters, new flashes, or a shadow in your vision should be evaluated within 24 hours. ER doctors can perform a basic evaluation and refer you to an ophthalmologist for a detailed retinal exam.
Normal exercise does not cause new floaters. However, if you already have a vitreous detachment in progress, heavy straining, jarring movements, or contact sports could increase the risk of a retinal tear. Talk with your eye doctor about activity restrictions if you have a recent PVD diagnosis.
In most cases, floaters are a normal part of aging and do not indicate a serious condition. Your eye doctor needs to examine your retina to confirm this, if the floaters are new. A dilated exam rules out retinal tears and other problems that could threaten your vision.
Protect Your Vision with Prompt Evaluation
Most floaters are harmless, but sudden changes deserve same-day attention. Contact your eye doctor if you notice any new floaters, flashes, or shadows in your vision.