Why am I suddenly seeing flashing lights in my vision?

By Sina Hartung, MMSC-BMI, Harvard Medical SchoolReviewed by Eureka Health Medical Group
Published: July 21, 2025Updated: July 21, 2025

Key Takeaways

Brief, repeated flashes that look like camera flashes inside one or both eyes usually mean the retina or optic pathway is being mechanically or electrically stimulated. Common causes range from harmless vitreous “tugging” to sight-threatening retinal detachment and, less often, migraine aura or brain disorders. Any new, persistent flashing—especially with floaters, shadow, or vision loss—warrants urgent same-day eye examination.

Are flashing lights in my vision usually serious?

Most short-lived light streaks come from the vitreous gel inside the eye pulling on the light-sensing retina. While many cases are benign, about 10 % hide a retinal tear that can steal vision if untreated. Therefore, every new onset of flashes deserves prompt evaluation.

  • Retinal traction sparks most flashesWhen the shrinking vitreous tugs the retina, it mechanically excites photoreceptors, producing white or silver arcs even in a dark room.
  • One in ten cases reveal a retinal tearLarge population studies show 8–15 % of patients who present with new flashes and floaters have a retinal break that needs laser sealing within 24 hours.
  • Migraine aura causes colored zig-zag lightsUp to 30 % of migraineurs experience scintillating scotoma that lasts 5–60 minutes and usually occurs in both eyes.
  • Occasional brain causes existOccipital lobe stroke, multiple sclerosis, or seizures can produce photopsia, but they account for less than 1 % of presentations in eye clinics.
  • Quote from the team at Eureka Health“Even eye-care professionals cannot reliably tell a harmless vitreous tug from a retinal tear without dilation and careful retinal mapping,” notes the team at Eureka Health.
  • Flashes plus new floaters call for same-day careThe American Academy of Ophthalmology urges people to seek immediate evaluation if flashes are accompanied by a burst of floaters or a curtain-like shadow, warning these paired symptoms often herald a retinal tear or detachment. (AAO)
  • Age over 40 increases vitreous-related flashesMichigan Medicine explains that posterior vitreous detachment becomes common after age 40, and the resulting tug on the retina is a frequent reason older adults notice spark-like lights. (UMich)

Which symptoms with flashing lights should make me call a doctor today?

Certain accompanying signs raise the likelihood of an urgent retinal problem or neurologic emergency. If any appear, ophthalmologists advise being seen within the same day, ideally within two hours.

  • Sudden shower of new floatersSeeing dozens of black dots or cobwebs raises the chance of retinal tear to roughly 50 %.
  • Dark curtain or peripheral shadowA moving grey shade in the side vision suggests a progressing retinal detachment; vision can drop permanently within 24–72 hours.
  • Eye pain or headache with weaknessFlashes plus unilateral weakness or slurred speech point toward a possible stroke and require calling emergency services.
  • History of high myopia or eye surgeryHighly nearsighted eyes and post-cataract patients have thinner retinas; their risk of detachment is threefold higher.
  • Quote from Sina Hartung, MMSC-BMI“Think of a curtain, cobweb, or storm of dots as red-alert signals—do not wait for tomorrow,” says Sina Hartung, MMSC-BMI.
  • Flashes after eye or head trauma require immediate evaluationThe American Academy of Ophthalmology says any flashes that follow a blow to the eye or face can indicate a retinal tear, warranting an urgent same-day dilated exam. (AAO)

What eye and brain conditions commonly trigger these light flashes?

Several mechanical, vascular, and neurologic processes can stimulate the retina or visual cortex. Recognizing patterns helps your clinician narrow the list.

  • Posterior vitreous detachment (PVD) after age 50About 60 % of adults over 50 experience a PVD; most flashes settle within 4–6 weeks as the gel separates completely.
  • Retinal tear or detachment in 6–10 per 10 000 peopleA full-thickness retinal break lets fluid seep behind the retina, lifting it like wallpaper.
  • Ocular migraine without headacheFlashes lasting 20 minutes, shifting across the field, and followed by no pain likely represent migraine aura.
  • Optic nerve inflammation (optic neuritis)Up to 30 % of optic neuritis patients see flashes when they move their eyes—a phenomenon called Uhthoff’s symptom.
  • Occipital lobe seizure or strokeBrief, repetitive colored lights in both eyes accompanied by neurologic deficits may originate from the brain.
  • Quote from the team at Eureka Health“Pattern and duration offer big diagnostic clues: seconds suggest retinal traction, minutes suggest migraine, and hours demand emergency care,” explains the team at Eureka Health.
  • Diabetic retinopathy can provoke flashing “shooting stars”Verywell Health notes that bleeding from damaged retinal vessels in diabetic retinopathy can form scar tissue that tugs on the retina, leading to photopsia. (Verywell)
  • Eye rubbing or head injury may trigger brief peripheral flashesMechanical pressure on the retina—such as vigorous eye rubbing or a recent concussion—can momentarily create arcs or sparkles of light, according to Healthline. (Healthline)

Can I do anything at home while I wait to be seen?

Self-care cannot repair a torn retina, but it can protect vision until you reach professional help.

  • Limit jarring head movementAvoid running or sudden bending; mechanical jolts can enlarge a small tear.
  • Rest with head uprightKeeping the head elevated reduces vitreous shifting; some surgeons believe this may slow fluid passage under a retinal flap.
  • Note the exact pattern and timingWriting down when flashes started and whether one or both eyes are involved helps the eye doctor target examination.
  • Do not drive yourself if vision is obscuredIntermittent darkening or blurred central vision triples accident risk—arrange a ride to urgent care.
  • Quote from Sina Hartung, MMSC-BMI“Jotting details while they’re fresh shortens clinic time and speeds any needed laser treatment,” advises Sina Hartung, MMSC-BMI.
  • Seek same-day medical evaluationThe American Academy of Ophthalmology urges calling an ophthalmologist immediately if you notice many new flashes, a side-vision shadow, or a gray curtain descending, as these can signal a retinal tear or detachment that needs urgent repair to preserve sight. (AAO)

Which tests and treatments might my clinician order?

An ophthalmologist uses specialized lenses and imaging to inspect the retina, then treats tears on the spot if found.

  • Dilated fundus examination is first-lineTropicamide drops enlarge the pupil for 30 minutes; a 90-diopter lens lets the doctor scan the retinal periphery.
  • Optical coherence tomography (OCT) for subtle splitsHigh-resolution cross-sections detect macular hole or shallow detachment invisible to the naked eye.
  • B-scan ultrasound if view is blockedWhen vitreous hemorrhage clouds the eye, ultrasound has 95 % sensitivity for detecting retinal detachment.
  • Laser photocoagulation seals most retinal tearsA 532 nm green laser places 3–5 concentric rings of burns, creating an adhesional scar within 24 hours.
  • Pneumatic retinopexy or vitrectomy for detachmentsGas bubble plus cryopexy reattaches the retina in select cases; success rates exceed 85 % when performed within one week.
  • Quote from the team at Eureka Health“Expect to spend about two hours in clinic—testing, pupil dilation, and treatment often happen the same day,” note the doctors at Eureka Health.
  • Cryotherapy freezes the retinal break when laser is not possibleDuke Health notes that outpatient cryopexy can be applied through the sclera to seal a tear when the retinal view is obscured, serving as an effective alternative to laser photocoagulation. (DukeHealth)
  • Vitrectomy removes cloudy gel and relieves tractionOC Retina explains that a pars plana vitrectomy clears blood, debris, and scar tissue while reducing vitreous pulling on the retina, preparing the eye for definitive repair of tears or detachments. (OC Retina)

Frequently Asked Questions

This content is for informational purposes only and is not intended as medical advice. Always consult with a qualified healthcare provider for diagnosis, treatment, and personalized medical recommendations.

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