Playing with a laser pointer may have left a young boy with permanent eye damage, according to a case study.
A 9-year-old boy visited an ophthalmology clinic in Larissa, Greece, complaining of vision problems in his left eye, the case study published in the New England Journal of Medicine says. Despite having 20/20 vision in his right eye, doctors found that his left eyesight was around 20/100 — a discrepancy explained by a hole on his left macula, a part of the retina that “provides sharp, central vision,” according to the National Eye Institute. Macular holes can cause blurry and distorted vision, and typically happen through eye trauma or as part of the natural aging process.
After interviewing the patient, doctors determined that his eye damage was likely caused by playing with and staring at the light of a green laser pointer. Given the extent of the damage, the boy’s doctors opted not to operate, and said his vision has not improved during 18 months of follow-up.
“Macular hole, in general, is usually repairable, but it doesn’t usually happen from laser pointers,” explains Dr. John Miller, director of retinal imaging at Massachusetts Eye and Ear. (Miller was not involved in the case.) “The laser actually heats up the tissue…and almost burns or vaporizes the retinal tissue, so it’s lost, as opposed to in the more typical traumatic injury or in the older patient population.”
Miller says most patients who experience laser-related damage see less-severe — but still potentially permanent — injuries, typically affecting only the outer retina. Massachusetts Eye and Ear sees in the ballpark of three to five such cases per year, he estimates.
Lasers can cause eye damage in as little as a few seconds, and anything from the power and wave length of a laser to the angle at which it’s viewed can affect the severity of an injury, Miller says. But based on the extent of the Greek boy’s injuries, Miller guesses that his exposure was prolonged.
“Most likely, with the size of the hole, this was an extended period of exposure,” he says. “It would not be likely to happen with a very brief exposure, but it’s hard to know.”
To play it safe, Miller recommends keeping kids away from laser pointers, even if they seem harmless.
“A laser pointer, to many, would seem safe, but there are many out there that are not properly screened and they don’t have the proper warnings,” Miller says. “If you notice your child is playing with it, take it away or very carefully look at it to make sure [it’s safe]. There’s really no reason kids should be playing with laser pointers, basically.”
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Write to Jamie Ducharme at jamie.ducharme@time.com