A 15-year old boy ordered a handheld laser pointer online. He wanted it to pop balloons from a distance and play around with, this included burning holes into paper cards and his sister’s shoes. Doctors from Lucerne Cantonal Hospital, Lucerne, Switzerland continue explaining in a letter published in the New England Journal of Medicine (NEJM) what happened when he used the laser pointer in front of a mirror.

The teenager wanted to create a “laser show” – he faced the mirror and zapped laser beams in several directions. Some of the beams hit his eyes and his vision in both eyes blurred immediately. He did not tell his parents for fear of being told off or perhaps causing unnecessary alarm, and hoped the vision problems would go away.

Two weeks passed and his eyesight problems continued. The boy went to see a health care professional.

The ophthalmic assessment revealed that his eyesight had deteriorated so badly in his left eye that he could only count fingers on a hand at a distance of no more than 3 feet (about 1 meter); his right eye had 20/50 acuity.

An examination of the interior of the eye with an ophthalmoscope detected a dense subretinal hemorrhage in his left macula, there were also several “tiny round scars in the pigment epithelium of the foveolar region of his right eye”. The clinician diagnosed bilateral retinal laser injury – injury to both eyes caused by laser beams.

Four months later the boy’s eyesight improved, but there were still some problems and scarring.

Laser pointers that were sold to the public used to have a maximum power of 5mW, which is not considered harmful for human eyesight. The handheld laser device the boy purchased on the internet was 150mW; 75 times more powerful, the authors wrote.

Lasers which are powerful enough to damage human eyesight are generally used only by military personnel, and in such cases accidents and injuries are extremely uncommon.

Laser devices with a potential of up to 700 mW can be bought by anyone on the internet, the Swiss doctors inform. There are government restrictions, but this does not seem to stop these products being available online – they are presented as “laser pointers”, like the ones lecturers use, and many look just like them.

These extremely powerful devices can cause serious and immediate eye injury. They are advertised as toys, even though they can cause blindness. Teenagers find them fascinating. There are even laser swords and other fun toys with powerful lasers installed inside them.

How is a child who is using one of these devices, and the other kids around him supposed to tell a harmless laser pointer from a dangerous one?

The authors conclude that if the present state of affairs continues, there will be more such eye injuries.

“Retinal Injuries from a Handheld Laser Pointer”
N Engl J Med 2010; 363:1089-1091September 9, 2010
Stefan Wyrsch, M.D., Philipp B. Baenninger, M.D., Martin K. Schmid, M.D., (Lucerne Cantonal Hospital, Lucerne, Switzerland)

Written by Christian Nordqvist