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Japan: Momentary exposure to Class 3B laser causes retinal injury

Note: The following abstract describes a retinal injury from momentary exposure to a Class 3B (between 5 and 500 milliwatts) green laser pointer. The paper itself is behind a paywall; the abstract is for those who may wish to buy the paper to obtain further details.

“In previously reported cases of retinal injury from red (He–Ne; 632 nm) laser pointers, the maximum output was 5 mW or lower (Class 3a), and gazing time was 10 s or longer. Higher-energy, green (532 nm) laser pointers are increasingly displacing red lasers and, here also, injuries have been reported. We report a case of retinal light damage caused, after a moment's gaze, by a high-output (Class 3b) green laser pointer unavailable to the general public in Japan that was brought from overseas.”

From “A case of retinal light damage by green laser pointer (Class 3b)”, Ueda, T., Kurihara, I. & Koide, R. Japanese Journal of Ophthalmology, July 2011, Vol. 55, Issue 4, pp 428-430, (2011) 55: 428. https://doi.org/10.1007/s10384-011-0031-5 First online July 1 2011.

Japan: Boy who routinely stared into a laser pointer develops lesion in one eye

A boy with intellectual disabilities “from the age of 2 to 3 years stared at [a green laser pointer] with his dominant right eye every day for more than 10 seconds at a time, as if it were a toy, at a distance of 30 cm [1 foot].”

At the age of 11, he had normal 20/20 (1.0) vision in the left eye, but 20/100 vision (0.20) in the right. Examination of the right eye showed a yellow lesion or fibrous tissue surrounded by a subretinal hemorrhage in the right macula. At age 13, examination showed the lesion was leaking on fluorescein angiography. At age 14, there was no change.

The doctors elected not to perform any treatment due to the patient’s age and mental condition.

From “Choroidal Neovascularization in a Child Following Laser Pointer-Induced Macular Injury”, Fujinami, K., Yokoi, T., Hiraoka, M. et al. Japanese Journal of Ophthalmology November 2010, Vol. 54, Issue 6, pp 631-633 (2010) 54: 631. https://doi.org/10.1007/s10384-010-0876-z First online January 21 2011.

Japan: Teen injured by LED pen "toy" held 40 seconds in his eye

NOTE: The injury described herein was NOT caused by a laser but by a light-emitting diode (LED). We are including it here because the measured power of 5 mW is similar to laser pointers, and because in mid-2013 the FDA proposed to regulate toys containing lasers. This case of an LED-caused injury may stimulate arguments on both sides. Additional discussion is in blue at the end of this story.

A December 2006 incident has come to our attention. A 15-year-old Japanese boy suffered a retinal injury and visual loss after deliberately looking into a 5 mW violet (410 nm) light emitting diode for a total of about 40 seconds. The LED was in a pen was sold as a toy called “Secret Pen”. The toy appears to consist of an LED light which can excite ink that is invisible under ordinary light but which fluoresces under ultraviolet and near-UV light. The 410 nm wavelength caused photochemical damage to the retina.

According to a 2011 paper in Retinal Cases & Brief Reports, the LED was aimed into the teen’s eye from a distance of about 1 cm. It was held there for about 20 seconds as he deliberately stared into the light. This exposure was repeated the next day. About two weeks later, decreased vision (20/50 on the Snellen scale) was noted in the right eye.
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