Occasionally, seeing flashing lights in the corner of your eye or tiny moving spots of light is called photopsia, and it’s usually not a cause for concern.
The most common cause of floaters or flashes of light is posterior vitreous detachment (PVD). The prevalence of PVD is 24% among adults aged 50-59 years and 87% among people older than 80 years. If you have this condition, you should see an eye doctor to make sure you don’t have a retinal tear or detachment.
If you have sudden repeated flashes in the form of bright spots, streaks of lightning, or shooting stars in the corner of your eye, you may have a retinal detachment, and you should see an eye doctor right away.
What Are Those Eye Flashes I’m Seeing
Eye flashes and eye floaters are often caused by changes in the vitreous gel, the substance that gives the eye its shape. Those changes can result from aging, extreme nearsightedness, or a previous eye surgery. As the vitreous gel changes consistency, it separates from the retina in a normal process called posterior vitreous detachment.
If the gel still adheres to the retina during separation, problems can occur. This is more likely to happen where the gel is more firmly attached, like at the periphery (side) of the retina. When the vitreous fails to separate cleanly and then tugs and creates friction on portions of the retina, eye flashes appear.
This tugging and friction can also result in a retinal tear. Fluid can enter the tear and cause retinal detachment, and if retinal detachment is left untreated, it can lead to permanent vision loss.
Here are some warning signs of a retinal tear:
- Repeated flashes that occur within seconds or hours of each other
- A sudden increase in floaters
- A curtain in front of the eye
- A loss of peripheral vision
- A narrowing of the visual field
Some people have an increased risk of developing eye floaters and flashes, including those who:
- Are over 50 years of age
- Have extreme nearsightedness
- Are diabetic
- Had a previous traumatic eye injury
What Causes Flashing Lights in the Eye?
Here are the top five causes of eye flashes and floaters.
1. Retinal Tear/Detachment
A retinal tear usually occurs when vitreous pulls from the retina or when there is an injury to the eye. It causes part of the retina to separate from the back of the eye.
There is a high risk of the tear getting larger and leading to a bigger separation called a retinal detachment. The initial symptoms of a retinal tear, including flashing lights and loss of vision, are similar to a detachment but are typically milder.
Symptoms of retinal tear/detachment:
- Many new floaters or showers of floaters
- A lot of bright flashes that don’t improve
- Sometimes it looks like a curtain is dropping down over your field of vision
- Side or sides of your vision become dark
- Complete vision loss in one or both eyes
A retinal detachment deprives the retina of oxygen and nutrients and is considered an emergency. If you have symptoms of retinal detachment or a retinal tear, you should see an ophthalmologist.
2. Posterior Vitreous Detachment
Posterior vitreous detachment (PVD) is the most common cause of floaters and flashing lights. It begins between the ages of 50 and 70, and it is caused by vitreous gel in the eyes partially liquifying and shrinking with age.
When this happens, the vitreous pulls on and separates from the retina. The parts of the gel that move around the eye cause floaters, and when the gel tugs at the retina, it can cause flashes of bright light.
Symptoms of floaters from PVD can get better with time as the gel-like pieces settle to the bottom of the eye. But if you have ongoing problems with vision, you may want to consider surgery. Since PVD can increase your risk of retinal detachment, the goal of surgery is to stabilize the retina.
Symptoms of PVD:
- Floating dark spots (can look like strings or cobwebs
- Flashes of light (can look like lightning or camera flashes)
- Floaters are more noticeable when looking at a plain light-colored background in bright light
- Symptoms are mild and come and go
3. Macular Degeneration
Macular degeneration occurs when the arteries to the macula (part of the retina) harden with age. This leads to less oxygen and nutrients to this area of the eye, which is responsible for clear and sharp central vision.
Symptoms of macular degeneration:
- Distorted or darkened central vision
- Loss of central vision
- Floaters or flashing lights
4. Migraine Disorder
Migraine disorders cause severe headaches that usually last from 4 to 72 hours, and people often have other symptoms like nausea and light or sound sensitivity. You may notice visual symptoms right before or during a migraine headache known as visual auras. Migraine with aura occurs in 25% to 30% of people with migraines. Some people have visual auras but no headache, which is known as ocular migraine.
Symptoms of migraine:
- Visual symptoms: bright or colorful spots, sparkles or shimmering lights, zigzagging lines, or stars
- Light or sound sensitivity
- Severe headache
5. Diabetic Retinopathy
Diabetes causes damage to blood vessels, including those in the retina, which is called diabetic retinopathy. The blood vessels become leaky, causing direct damage to the retina. Then the eye starts to form new blood vessels because of this damage. These new blood vessels are more likely to leak blood and other fluid, which causes vision to become blurry or hazy. The new blood vessels can also cause scars that tug at the retina and cause a retinal tear or detachment, which may cause you to see spots, flashes of light, or blind spots.
Both diabetes and macular degeneration can cause macular edema, which may lead to unusual visual symptoms where objects look distorted or wavy.
When Should You See a Doctor?
If you experience a sudden increase in eye flashes and floaters or any other warning signs of a retinal tear, you should see an eye doctor.
You should also visit an eye doctor if you experience any of the following symptoms:
- Blurred vision
- Darkening vision
- Vision loss
- An eye injury
- Frequent ocular migraines (episodes of vision loss in one eye, usually lasting less than one hour and associated with a headache)
- Vision changes
Expert Eye Care at Toledo LASIK
As always, if you have any unusual visual symptoms, you should schedule an appointment with an eye doctor.
If you’re struggling with decreased vision due to cataracts, extreme myopia (nearsightedness, or hyperopia (farsightedness), the expert eye doctors at Toledo LASIK can help you find the solution that’s right for you. In addition to treating common vision problems, we can provide multiple vision correction options and premium cataract procedures that are tailored to your specific vision needs.