Floaters and flashes: when they can wait and when they should not
Floaters and flashes are common, especially as the eye changes with age. Many are caused by changes in the vitreous gel and are not dangerous by themselves. But a sudden increase in floaters or flashes, a dark curtain or shadow, or new blurred or missing vision can be a warning sign of a retinal tear or retinal detachment and should be checked promptly.
🧠 Dr. Roque’s Quick Answer
Most floaters and flashes are not an emergency, but some are. If you suddenly notice many new floaters, repeated flashes, a curtain or shadow in your vision, or any drop in vision, I would treat that as urgent until a dilated retinal examination proves otherwise.
🧩 Focus
Help you decide whether floaters and flashes sound routine or urgent.
👁️ Goal
Recognize the warning signs of retinal tear or retinal detachment and know the next step.
🛡️ Evidence-Based
Sudden new floaters or flashes can be linked to posterior vitreous detachment, retinal tear, or retinal detachment.
🚨 Dr. Roque’s Emergency Warning
Please do not ignore floaters and flashes if they are sudden, clearly increasing, or associated with any loss of vision.
- a sudden shower of new floaters
- repeated bright flashes, especially in side vision
- a curtain, shadow, or dark area in your vision
- blurred, distorted, or missing vision
- symptoms after eye trauma
🧠 Dr. Roque’s Key Learning Points
- Floaters often look like specks, cobwebs, threads, dots, or drifting shadows.
- Flashes are brief streaks, sparks, or lightning-like flickers, often more noticeable in the dark.
- Many cases are related to age-related changes in the vitreous gel.
- What matters most is not just the symptom itself, but whether it is new, sudden, worsening, or associated with vision loss.
- A normal eye can still have harmless floaters, but a retinal tear or retinal detachment must be ruled out when the story sounds suspicious.
What floaters and flashes usually mean
The inside of the eye is filled with a clear gel called the vitreous. As we age, that gel becomes more watery and less uniform. Tiny strands or clumps can cast shadows on the retina, and those shadows are seen as floaters. If the vitreous pulls on the retina, you may notice flashes of light.
In many patients, this is part of a process called posterior vitreous detachment, or PVD. PVD is common and often settles down. But the same pulling process can sometimes create a retinal tear. If fluid passes through that tear, part of the retina can lift off, causing a retinal detachment. That is why the story matters so much.
In other words, floaters and flashes may be harmless, but they can also be the first warning sign of a problem that threatens vision.
🧬 Anatomy Micro-Primer
Think of the eye like a small camera.
- Vitreous: the clear gel filling the center of the eye
- Retina: the thin light-sensitive layer lining the back of the eye
- Macula: the central part of the retina used for detailed vision
When the vitreous changes, you may see floaters. When it pulls on the retina, you may notice flashes. If the retina tears or detaches, vision can be permanently affected if treatment is delayed.
📘 Terminology Glossary
- Floaters: moving spots, lines, cobwebs, or shadows seen in the vision
- Flashes: brief flickers or lightning-like lights that are not coming from outside the eye
- PVD: posterior vitreous detachment, when the vitreous separates from the retina
- Retinal tear: a break in the retina that may lead to retinal detachment
- Retinal detachment: when the retina lifts away from the back of the eye and may threaten permanent vision
How patients describe these symptoms
Floaters may sound like
- black dots or pepper-like specks
- cobwebs or threads drifting across vision
- clouds, rings, or translucent shapes
- spots that move when the eye moves
Flashes may sound like
- lightning streaks at the side of vision
- brief sparks or flickers
- camera-flash sensations in the dark
- repeated flashes when moving the eye
When this is more likely to be routine
A few long-standing floaters that have not changed much over time are often less concerning. Some patients notice them more against a bright sky, a white wall, or a computer screen. Mild floaters can persist for a long time and may become less noticeable as the brain learns to ignore them.
Flashes that are brief and settle down after a careful retinal examination may also turn out to be related to benign vitreous changes. But please do not assume that on your own. What makes me more comfortable is a stable story, no curtain, no vision loss, and a proper dilated retinal exam that shows no tear.
The important point is this: “common” does not mean “ignore it.” New symptoms still deserve proper assessment.
When I would worry more
| Symptom pattern | Why it matters | What to do |
|---|---|---|
| sudden shower of many new floaters | may suggest acute vitreous change, bleeding, or retinal tear | seek urgent dilated retinal examination |
| repeated new flashes | may mean the vitreous is pulling on the retina | seek urgent assessment |
| curtain, shadow, or dark area | can be a classic retinal detachment warning sign | treat as an emergency |
| drop in vision or blurred missing area | may indicate retinal involvement or bleeding | same-day evaluation is wise |
| symptoms after trauma | raises concern for retinal injury or bleeding | urgent eye examination |
💡 Dr. Roque’s Analogy
Imagine wallpaper on a wall. If a little dust floats in front of it, that is like a harmless floater. But if the wallpaper starts to peel away from the wall, that is more like a retinal tear or retinal detachment. The patient may still say, “I just see floaters and flashes,” but the underlying issue is very different. That is why the symptom needs context.
What happens during the eye check
The key test is usually a dilated retinal examination. Drops are used to enlarge the pupil so the retina can be examined properly. Depending on the situation, the visit may also include vision testing, eye pressure measurement, slit lamp examination, and sometimes retinal imaging or ocular ultrasound if the view is limited.
What I am trying to answer during that visit is simple:
- Is this a straightforward vitreous detachment?
- Is there a retinal tear?
- Is there any bleeding inside the eye?
- Is there already retinal detachment?
Treatment depends on the cause
If it is a simple PVD
Many patients do not need surgery or laser. Observation and return precautions may be enough. Floaters often become less bothersome with time, although they do not always disappear completely.
If there is a retinal tear
Laser treatment or freezing treatment may be used to seal the tear and reduce the chance of progression to retinal detachment.
If there is retinal detachment
Surgery may be needed, and timing matters. The earlier this is recognized and treated, the better the chance of protecting vision.
Who may be at higher risk
These factors do not prove that something serious is happening, but they make me more cautious:
- older age
- high myopia or very nearsighted eyes
- history of retinal tear or retinal detachment
- recent eye surgery, including cataract surgery
- eye trauma
- bleeding inside the eye or other retinal disease
What you should do right now
| Your situation | Best next step |
|---|---|
| a few old stable floaters, no change, no flashes, no vision loss | routine eye review may be reasonable |
| first episode of new floaters or flashes | book a prompt dilated examination |
| sudden increase in floaters, recurrent flashes, or symptoms after trauma | urgent same-day or next-available retinal evaluation |
| curtain, shadow, missing vision, or clear drop in sight | treat as an eye emergency |
Frequently asked questions
Are floaters always dangerous?
No. Many floaters are benign. What concerns me is a sudden change, a large increase, or floaters associated with flashes, shadow, or reduced vision.
Are flashes always a retinal detachment?
No. Flashes can happen with vitreous traction during PVD. But because the same process can create a tear, new flashes still deserve proper examination.
What does a retinal detachment feel like?
Patients often describe increasing floaters, flashes, and then a curtain, veil, shadow, or missing area of vision. It is usually not painful.
Can floaters go away?
Some become less noticeable over weeks to months. Others remain but become easier to ignore. Persistent severe floaters are a separate discussion and not usually an emergency by themselves.
Should I wait and see for a day or two?
If the symptoms are new and clearly different, I would rather not guess. Prompt retinal examination is the safer choice.
Can both eyes be affected?
Yes. The symptoms may start in one eye, but vitreous changes can happen in either eye over time.
✅ Dr. Roque’s Take-Home Message
Floaters and flashes are common, but the important question is whether they are sudden, worsening, or accompanied by a curtain, shadow, or drop in vision. If that is the story, please do not rely on reassurance from the internet. Have the retina examined properly and promptly.
🔗 Related Reading
📚 References
- National Eye Institute. Retinal Detachment.
- National Eye Institute. Vitreous Detachment.
- National Eye Institute. Floaters.
- American Academy of Ophthalmology. What Are Floaters and Flashes?
- American Society of Retina Specialists. Posterior Vitreous Detachment.
- American Society of Retina Specialists. Retinal Tears.
- NHS. Floaters and flashes in the eyes.
🤝 ROQUE Eye Clinic Patient Education Series
Reviewed by the Roque Advisory Council
Dr. Manolette Roque | Dr. Barbara Roque
St. Luke’s Medical Center Global City | Asian Hospital Medical Center | Philippines
Medical Review: Reviewed by the Roque Advisory Council
Last Updated: April 4, 2026
Medical Disclaimer: This article is for general educational purposes only and does not replace a proper eye examination or personalized medical advice.
