Flashes and Floaters: Retinal Tears & Detachments

Why a sudden burst of floaters or lightning-like flashes in one eye should not wait until next week

Dr. Will Flanary (Dr. Glaucomflecken)

37 min · 3 min readExpert: Dr. Will Flanary (Dr. Glaucomflecken)|Watch episode|
Humans

What this episode covers

  • A sudden shower of new floaters or lightning-like flashes in one eye can sometimes signal a retinal tear or detachment.
  • The retina is the light-sensing wallpaper at the back of your eye, and when the gel inside the eye pulls on it, it can tear.
  • Getting a dilated eye exam within 24 hours is the standard of care.
  • Seek urgent medical attention sooner if you also notice a dark curtain, shadow, or missing area in your vision.

Why it matters

If a retinal tear progresses to a detachment, it can affect central vision, peripheral vision, depth perception, driving safety, and daily independence. Catching it early may allow a quick laser repair instead of a more involved surgery.

What stands out

  • Most retinal tears happen in the peripheral retina, not the central part used for reading, so vision can stay normal at first even when a tear is present (clinical observation).
  • Being nearsighted (myopic) is not just a glasses issue; it is also a small but real risk factor for retinal tears because the eye is longer and the retina is thinner (mainstream ophthalmology consensus).
  • An ultrasound in the emergency department often does not change what the ophthalmologist does, because a dilated retinal exam is the actual decision-making test (expert clinical practice).
This is one of multiple expert perspectives. The full topic combines them into clear guidance.Explore full topic →

One key action from this episode

What to do

Actions discussed in this episode. This is what one expert recommends — the full topic compares and ranks across experts.

  • Consider booking a dilated eye exam within 24 hours of any new flashes or a sudden shower of floaters, especially if you are nearsighted. Seek immediate care if you also notice a dark curtain, shadow, or missing area in your vision.
  • Consider calling your eye doctor's on-call line first for new flashes or floaters; if none is available, go to the emergency department the same day.
  • If you have had a recent retina surgery with a gas bubble, avoid air travel until your surgeon clears you, to prevent gas expansion at altitude.

Full context, impact ratings, and timing — available in related topics

Most relevant for:Nearsighted adultsPeople over 40Anyone with new floatersAnyone with sudden flashes of lightPost-eye-surgery patients

Questions to take to your doctor

Questions worth asking based on this episode
  • Given my new floaters and flashes in one eye, would a same-day dilated retinal exam meaningfully change my treatment, or is it safe to wait a few days?
  • Given that I am nearsighted, is it worth a routine peripheral retinal check at my next visit, even without symptoms?
  • Given my recent retina surgery with a gas bubble, when is it actually safe for me to fly or drive into the mountains again?

Full doctor prep with ranked questions available in the full topic page

This is one expert perspective. The full topic ranks actions across multiple experts.Explore full topic →

Context

How this expert sees it

The expert emphasizes translating research into actionable steps, focusing on what the evidence actually supports versus common assumptions.

What we don't know yet

This episode is a clinician explaining a standard-of-care pattern, not a study of individual outcomes. It does not predict who will or will not develop a tear, and it cannot replace a dilated eye exam in your own eye. This does not mean you should change or stop your current eye care on your own.

Where people go wrong

  • Waiting days to see if new flashes or floaters go away on their own.A small retinal tear may progress to a detachment, making surgery more complex and outcomes less predictable.
  • Assuming "lots of floaters are normal" when the change is sudden, one-sided, or paired with flashes.A treatable tear can be missed in the window where simple laser repair may still be enough.

What to expect over time

  • First symptoms (hours)A lightning-like flash or a sudden cloud of new floaters in one eye, often after a jolt or in middle age.
  • Within 24 hoursA dilated eye exam checks the retina; a tear may be treated with laser, a detachment is referred to a retina specialist.
  • After treatmentVision recovery varies by how much retina was involved; some people regain near-normal sight, others have lasting changes.
This is one expert's perspective. The full topic shows where experts agree and disagree.Explore full topic →