Seeing flashes of light in your vision can be surprising, especially when they appear suddenly or only in one eye. While occasional flashes can have harmless causes, new or sudden flashes may sometimes be a warning sign of a retinal problem and should not be ignored.

What Causes Flashes of Light?

Flashes can occur when the vitreous, the gel-like substance inside the eye, moves or pulls on the retina. This can happen as part of normal ageing, particularly when the vitreous begins separating from the retina.

In some cases, however, this pulling can create a retinal tear. If a retinal tear is not identified and treated, it can potentially progress to retinal detachment.

When Should You Be Concerned?

Pay particular attention if flashes occur together with:

• A sudden increase in eye floaters
• New dark spots or cobweb-like shapes
• Blurred or reduced vision
• A shadow or curtain appearing in your field of vision
• Symptoms occurring suddenly in one eye

These symptoms can indicate a retinal tear or retinal detachment and require prompt evaluation.

Can Flashes Happen Without a Retinal Problem?

Yes. Flashes can sometimes occur due to migraine or other visual disturbances. However, it is difficult to determine the cause based on symptoms alone.

A retinal examination allows an eye specialist to examine the retina and check for tears, detachment, or other abnormalities.

Who Is More at Risk?

The risk of retinal problems can be higher in people who:

• Are older
• Have high myopia
• Have previously undergone eye surgery
• Have experienced an eye injury
• Have a family history of retinal detachment
• Have certain retinal conditions

What Should You Do If You See New Flashes?

If you suddenly develop flashes, particularly when accompanied by new floaters or a shadow in your vision, don't wait for the symptoms to disappear.

A prompt examination by a retina specialist can help determine whether the retina is healthy or whether treatment is required.

Final Takeaway

Not every flash of light means there is a serious eye problem. However, sudden flashes—especially when combined with floaters or changes in vision—should be evaluated promptly.

Early detection of a retinal tear or retinal detachment can be important for protecting vision.