Specialty Vision · Vision Simulator
Sudden Vision Changes — Warning Signs Simulator
Some vision changes are emergencies: a sudden burst of flashes or floaters, a dark curtain creeping across your sight, or sudden loss of vision can threaten your eyesight and are far more treatable when caught early.
When to act fast
Some vision changes are emergencies. A sudden burst of flashes or floaters, a dark curtain creeping across your sight, or a retinal tear can threaten your vision and are far more treatable when caught early. These simulations show what those warning signs can look like — if you experience them, contact an eye doctor urgently.
Overview
Most vision changes develop slowly and aren't urgent — but a few come on suddenly and are warning signs that need same-day care. Flashes of light and a sudden shower of new floaters can mean the gel inside the eye is tugging on the retina, sometimes tearing it. A shadow or 'curtain' spreading across your vision can mean a retinal detachment. Sudden, painless loss of part or all of your vision can come from a retinal or optic-nerve problem, a blocked blood vessel, or a stroke. Acting fast can save sight.
When to see an eye doctor
If you experience any of the warning signs below, contact an eye doctor or emergency service right away — don't wait to see whether they pass. Conditions such as a retinal tear or detachment are far more treatable in the first hours and days, and sudden painless vision loss can signal a stroke. When in doubt, get checked: a same-day exam is worth the reassurance.
Seek urgent care for:
- A sudden shower of new floaters
- New flashes of light, especially together with floaters
- A dark curtain, shadow or veil moving across your vision
- Sudden loss of part or all of your vision (painless or painful)
- Sudden double vision, or vision loss with a severe headache, weakness or slurred speech (possible stroke)
Frequently asked questions
Are new floaters and flashes an emergency?
A sudden increase in floaters or new flashes of light can mean the eye's gel is pulling on the retina and possibly tearing it, which can lead to a retinal detachment. Get an urgent eye exam — a tear is far easier to treat before the retina detaches.
What does a retinal detachment look like?
Often a dark curtain or shadow spreading across part of your vision, usually painless, frequently preceded by flashes and a burst of floaters. It is a medical emergency, and prompt treatment gives the best chance of saving vision.
I suddenly lost vision but it didn't hurt — should I worry?
Yes. Sudden, painless loss of vision in one eye can come from a retinal or optic-nerve problem or a blocked blood vessel, and can be a sign of a stroke. Treat it as an emergency and seek care immediately.
When is double vision an emergency?
New, sudden double vision — especially with a severe headache, a droopy eyelid, weakness or slurred speech — can signal a nerve or brain problem, including a stroke, and needs emergency care.
Sources
- What Are Floaters and Flashes? — American Academy of Ophthalmology
- Detached and Torn Retina — American Academy of Ophthalmology