Seeing small shapes drifting across your vision or sudden flashes of light can understandably be concerning. Flashes and floaters are common visual symptoms and, in many cases, are caused by natural changes that occur inside the eye as we get older.
However, a sudden appearance or increase in flashes or floaters can sometimes be a warning sign of a more serious problem affecting the retina.
Knowing the difference between long-standing symptoms and those requiring urgent attention is important for protecting your sight.
At The Medical Eye Clinic in Exeter, our specialists can assess flashes and floaters and examine the back of the eye for conditions such as posterior vitreous detachment, retinal tears and retinal detachment.
What Are Eye Floaters?
Floaters are small shapes that appear to move across your field of vision.
They may look like:
- Small black or grey dots
- Specks
- Lines
- Threads
- Rings
- Cobwebs
- Irregular shapes
They can be particularly noticeable when looking at a bright, plain background such as a white wall, computer screen or clear blue sky.
Although they may appear to be in front of your eye, floaters are actually caused by changes within the vitreous – the clear, jelly-like substance filling the inside of the eye.
Small strands or clumps within the vitreous cast shadows onto the retina at the back of the eye, which you perceive as floaters.
What Are Flashes in Your Vision?
Flashes are brief sensations of light that occur without an external light source.
They may appear as:
- Flickering lights
- Brief flashes
- Sparkles
- Streaks of light
- Flashes towards the edge of your vision
One common reason for seeing flashes is movement of the vitreous inside the eye.
As the vitreous changes and begins to pull away from the retina, it can temporarily tug on the light-sensitive retinal tissue. The retina responds to this stimulation by sending signals to the brain, which you perceive as flashes of light.
What Causes Flashes and Floaters?
One of the most common causes of flashes and floaters is a process known as posterior vitreous detachment (PVD).
As we age, the vitreous becomes more liquid and gradually changes shape. Eventually, it can begin to separate from the retina at the back of the eye.
This is called posterior vitreous detachment.
PVD is a common age-related change and in most cases does not cause serious problems. However, when the vitreous separates, it can occasionally pull strongly enough on the retina to cause a retinal tear.
This is why a sudden onset of flashes or floaters should be professionally assessed.
Are Flashes and Floaters Normal?
Having one or two floaters that have been present for a long time and are not changing is often not a cause for concern.
Floaters can become increasingly common with age and may gradually become less noticeable as your brain adapts to them.
Similarly, flashes associated with an uncomplicated PVD may reduce and eventually settle.
The important consideration is whether your symptoms are new, sudden or changing.
A significant change in your vision should not be ignored.
When Should You Be Concerned About Flashes and Floaters?
You should seek urgent professional advice if:
- You experience flashes or floaters for the first time
- Floaters appear suddenly
- The number of floaters suddenly increases
- You notice a sudden shower of dots or specks
- Flashes become more frequent or suddenly appear
- You develop blurred or reduced vision
- You notice a dark shadow in your vision
- A curtain or veil appears across part of your vision
- Symptoms occur following an eye injury
- Symptoms develop after eye surgery
These symptoms can sometimes indicate a retinal tear or retinal detachment, which requires prompt assessment and treatment.
What Is a Retinal Tear?
The retina is the thin, light-sensitive layer of tissue lining the back of the eye.
During a posterior vitreous detachment, the vitreous can occasionally pull strongly enough on the retina to create a tear.
A retinal tear may allow fluid to pass underneath the retina. If this happens, the retina can begin separating from the wall of the eye, resulting in a retinal detachment.
Detecting a retinal tear early is important because treatment may be able to prevent it from progressing to a retinal detachment.
What Is Retinal Detachment?
Retinal detachment occurs when the retina separates from the tissues supporting it at the back of the eye.
This is a serious eye condition that requires urgent treatment.
Possible warning signs include:
- A sudden increase in floaters
- New flashes of light
- Sudden blurred vision
- A dark shadow appearing in your vision
- A curtain or veil moving across your field of vision
Retinal detachment is usually painless, so the absence of eye pain does not mean that sudden visual changes can safely be ignored.
Prompt treatment is important because an untreated retinal detachment can result in permanent loss of vision.
Does Everyone With Flashes and Floaters Have a Retinal Problem?
No.
Most people who develop flashes and floaters will not have a retinal detachment. An uncomplicated posterior vitreous detachment is a common cause of these symptoms.
However, it is impossible to reliably determine the cause based on symptoms alone.
An examination of the back of the eye allows an eye-care professional to check the retina and determine whether there is evidence of a tear, detachment or another condition requiring treatment.
Who Is More at Risk of Retinal Detachment?
Anyone can develop retinal problems, but certain factors can increase your risk.
These include:
- Being significantly short-sighted
- Increasing age
- Previous cataract or other eye surgery
- Previous eye injury
- A previous retinal tear or detachment
- A family history of retinal detachment
If you have one or more of these risk factors, it is particularly important to seek prompt advice if you notice sudden changes to your vision.
What Happens During an Examination for Flashes and Floaters?
If you develop new flashes and floaters, your eye-care professional will need to examine the back of your eye.
This will usually involve dilating your pupils with eye drops so the retina can be examined thoroughly.
Your specialist will look for signs of:
- Posterior vitreous detachment
- Retinal tears or holes
- Retinal detachment
- Bleeding within the eye
- Other retinal abnormalities
Dilating drops temporarily make your pupils larger and can cause blurred vision and sensitivity to light for several hours.
Your clinician will explain what to expect and advise you about driving following your examination.
Do Flashes and Floaters Go Away?
This depends on their cause.
Flashes associated with a posterior vitreous detachment often become less frequent and may eventually disappear.
Floaters can persist for longer. However, many people find they gradually become less noticeable as the brain learns to ignore them.
If your floaters remain particularly troublesome or interfere significantly with your vision, specialist treatment may sometimes be considered.
Can Eye Floaters Be Treated?
Most floaters do not require treatment.
If your retina is healthy and the floaters are not significantly interfering with your vision, observation may be all that is required.
For patients with persistent and particularly troublesome floaters that significantly affect their vision or everyday activities, treatment may occasionally be considered.
The Medical Eye Clinic provides specialist assessment and vitreo-retinal surgery for suitable patients with symptomatic floaters.
The benefits and risks of treatment need to be considered carefully, which is why a comprehensive assessment with an experienced ophthalmologist is important.
Can You Prevent Flashes and Floaters?
Age-related changes to the vitreous cannot generally be prevented.
However, being aware of your symptoms can help ensure retinal problems are identified promptly if they occur.
Pay particular attention to any sudden change in the number or appearance of your floaters, the development of new flashes, or changes to your field of vision.
When Should You Seek Urgent Help?
New or suddenly worsening flashes and floaters should always be taken seriously.
Seek urgent eye-care advice if you suddenly develop:
- New flashes or floaters
- A significant increase in existing floaters
- A shower of new floaters
- A dark shadow or curtain across your vision
- Sudden blurred or reduced vision
These symptoms can indicate a retinal tear or retinal detachment and require prompt assessment.
If you cannot access an eye-care professional urgently, contact NHS 111 for advice.
Specialist Flashes and Floaters Assessment in Exeter
Although flashes and floaters are often caused by harmless age-related changes, sudden symptoms should never simply be assumed to be normal.
A detailed eye examination can determine whether your symptoms are associated with an uncomplicated posterior vitreous detachment or whether there is a retinal problem requiring treatment.
At The Medical Eye Clinic in Exeter, our specialist ophthalmologists provide comprehensive assessment and treatment for conditions affecting the vitreous and retina.
If you are concerned about changes to your vision, contact our team to discuss the appropriate next steps.
Frequently Asked Questions
Are flashes and floaters dangerous?
Flashes and floaters are often caused by harmless changes to the vitreous inside the eye. However, sudden new symptoms can sometimes indicate a retinal tear or retinal detachment and should be assessed urgently.
What do eye floaters look like?
Floaters can look like dots, specks, threads, lines, rings or cobweb-like shapes moving across your vision. They are often easier to notice against a bright background.
Why am I suddenly seeing lots of floaters?
A sudden increase in floaters can occur when the vitreous separates from the retina during a posterior vitreous detachment. However, a sudden shower of floaters can also occur with a retinal tear or bleeding within the eye, so you should seek urgent professional advice.
Should I worry about flashes in one eye?
New flashes in one eye should be assessed, particularly if they appear suddenly or occur alongside new floaters, blurred vision or a shadow in your field of vision.
What does a retinal detachment look like?
Warning signs can include sudden flashes and floaters, blurred vision or a dark shadow, curtain or veil spreading across your field of vision. Retinal detachment requires urgent medical attention.
Can flashes and floaters disappear on their own?
Flashes may gradually settle, while floaters often become less noticeable over time. However, new or suddenly changing symptoms should still be assessed to rule out retinal problems.