Laser pointer risks at close range

Cases of permanent retinal damage in children from modern-day laser pointers far outweigh those of airplane and helicopter pilots who are subjected to deliberate laser strike, a new BMJ Ophthalmology editorial emphasises.

Authors Professor John Marshall, Dr John O’Hagan and Professor John Tyrer note that an estimated 150 children in the UK have suffered foveal injuries from laser pointer devices since stronger devices hit the market eight years ago.

This compares to the one case of a pilot in a laser-targeted aircraft, which Professor Marshall told OT was “suspect” as the fundus anomaly is in the wrong location.

The overall evidence indicates that the eye cannot be damaged permanently at such a long distance from the device – but the temporary distraction can still have catastrophic consequences, Professor Marshall emphasised.

He added: “Under no circumstances should lasers been shone at people’s eyes, and it is particularly dangerous for pilots, train drivers and car drivers as the dazzle and distraction can have really awful consequences.”

Professor Marshall said the editorial was “an attempt to address the misinformation dissipated by the mass media concerning ‘blinding’ of pilots. This is a complete misunderstanding of the nature of laser tissue interactions over long ranges.”

The atmosphere and cockpit windshield will act to scatter the retina-damaging energy of the device before it reaches the pilot’s eye, the editorial explained.

The devices that are currently commercially available are capable of producing irreversible retinal damage if aimed at the eye at any distance up to a few metres away, he said.

Professor Marshall also emphasised that current laser pointer standards – which are “almost universal” around the world – are sufficient.

“Contrary to media concern they do not need revision, but, clearly, further attempts must be made to educate the public.”

However, he highlighted that one concern is internet retailers selling devices that are more powerful than allowed for public sale under these regulations. Another issue is poor manufacturer compliance to these standards, with devices over the energy limit being “mislabelled” as safe for general sale, Professor Marshall explained.

AOP chairman, Kevin Thompson, was interviewed on Capital radio today (20 April) about the editorial’s release.

He explained: “The key message here is that laser pens are not toys. And people should never aim a laser at people’s eyes, or animals’ eyes, or an aircraft or vehicles of any sort.”

Mr Thompson also said that, even though retinal damage was unlikely at a long distance, he advised a pilot or driver who had suffered a laser strike to visit an optometrist to have their eyes checked.

Asked about the dangers of the dazzle effect, he explained: “It only takes one pilot to be momentarily blinded for one moment to potentially destroy the lives of many. It’s not big, it’s not clever and anyone who knows of people persisting in this ridiculous pastime should report them immediately to the police.”

AOP professional adviser, Geoff Roberson, told OT that: “The editorial very helpfully dispels the myth that pilots are at risk of retinal damage whilst highlighting the wider risk of dazzle and distraction during critical phases of flights.”

A laser device’s ability to damage the retina depends on the amount of energy able to enter the eye before a person blinks or shifts their eye or head.

A newly designed laser system – published in the journal Optics Letters – could be used in ophthalmology, as only a small fraction of the energy reaches the retina, after most is absorbed by the cornea and lens.

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