High-power blue laser gadgets can cause serious eye damage

Nov 14 2013

Prompt treatment can lower risk of permanent vision loss

A type of high-power blue laser toy readily available over the Internet and increasingly popular among male teens and young adults can cause serious, sometimes irreversible, eye damage, according to a report by investigators from Saudi Arabia’s King Khaled Eye Specialist Hospital (KKESH) and Johns Hopkins Medicine. The two institutions have collaborated on clinical care, medical education and research since 2010.

The report, published online Nov. 4 in the journal Ophthalmology, describes a cluster of 14 cases of previously unseen laser-induced eye damage treated at KKESH hospital between 2012 and 2013. All injuries were caused by high-power blue laser gadgets and included four cases of perforations of the retina, the nerve-rich, light-sensitive innermost layer of the eye responsible for detailed central vision.

“We fear our experience may mark the beginning of an alarming trend and may portend a growing number of young people suffering serious eye damage as these high-power lasers become more ubiquitous,” says J. Fernando Arevalo, M.D., the Edmund F. and Virginia B. Ball Professor of Ophthalmology at the Johns Hopkins Wilmer Eye Institute, chief of the retina division at KKESH and principal investigator of the Collaborative Retina Study Group there.

Arevalo says 16 more patients have been seen and treated at KKESH for laser-induced injuries since the writing of the report.

The authors of the report say these high-power laser toys resemble the more benign low-power laser pointers used during presentations and can be easily confused with them.

The investigators say the warning labels that such devices carry are apparently not enough to prevent injuries, and they urge physicians, parents and educators to talk to children about the dangers of these devices. In addition, the authors say, physicians should inquire about laser-device use in all cases of unexplained sudden loss of vision, particularly among boys, teens and young males, among whom such devices are most popular.

The patients in the study all experienced sudden loss of vision in one eye and either brought their devices with them to the emergency room or reported being exposed to such a device. Ten of the 14 patients required surgery or another intervention, and while most of the injuries were reversed with treatment, two patients sustained permanent damage to the retina. All patients recovered some or most of their vision over the course of a few weeks or months.

All patients sought treatment promptly, which may explain their successful recovery, say the authors and urge patients, parents and caregivers to seek immediate medical attention if vision is affected while using the device.

All injuries occurred during play and involved teenage boys and young males, between the ages of 11 and 30. Some injuries were accidental, but others involved a playmate intentionally pointing the laser beam at the victim’s eye. The distance between the victim’s eye and the laser beam ranged from 1.7 feet to 20 feet (a half-meter to 6 meters). Those who suffered retinal holes were injured at the closest distance, around half meter, or 1.7 feet. Generally, injury from greater distance resulted in less serious damage, the authors of the report say.

The investigators say such severe laser-induced eye damage is a new phenomenon stemming from the growing popularity of novel high-power laser gadgets. While blue laser technology has been used for a long time in medical diagnostics and electronic equipment, blue lasers have only recently been packaged as toys for mass consumption. Resembling light sabers from Star Wars, such devices are most often used for play but also to light cigarettes and set plastic or paper on fire from a distance.

High-power lasers can damage the retina by shooting a powerful light current into the eye that penetrates the organ’s deepest layers in fractions of a second. The eye’s protective blink reflex is not fast enough to shut out the laser beam. In comparison, low-power laser pointers are relatively safer with short exposure because they emit a much weaker current that is blocked out by the blink reflex before it reaches the deep layers of the eye. Blue lasers are also more dangerous than red and green ones because blue is more easily absorbed by pigments in the retina and thus more damaging to it.

“These are potent, dangerous devices capable of inflicting serious injury, yet easily accessible and vastly appealing to a segment of the population that is anything but cautious,” says ophthalmologist Saba Al-Rashaed, M.D., senior author on the report and associate chief of the retina division at KKESH.

Specifically, the lasers burned holes in the maculas of four patients in the study. The macula is the highly light-sensitive center of the retina. All four underwent surgery to close the holes, and all experienced improved vision. Five patients suffered retinal bleeding, three of whom were treated successfully with laser therapy. Two of the five did not improve as a result of treatment because the bleeding had produced clots resulting in permanent damage to the retina. Two patients had bleeding around the fovea, the central part of the macula. Both of those injuries resolved on their own over a few months. Two patients sustained splitting of the retinal layers, which healed spontaneously. One patient underwent a procedure to remove scar tissue and abnormal fluid buildup under the retina.

The authors of the report are planning on asking the Saudi government to consider a ban on the sale of blue laser devices.

Source: http://www.hopkinsmedicine.org/