Laser exposures can have a wide range of effects including flash blindness, dazzle, dark spots, hazy vision, floaters, burns, retinal bleeding, etc. Of special interest are the hazards posed by visible lasers from glare and flash blindness, and from very high energy lasers that could cause serious thermal injuries. Luckily, the part of the eye responsible for most of our central vision is about the size of a pinhead. It is possible, that this area could be damaged by a laser, but only if a person happened to be looking directly at the light.
A laser injury even a few millimeters away from this area, will probably not significantly affect the central vision.
The central vision is what you use to read, watch TV, and drive. Most people after encountering a laser incident quite naturally start to become overly conscious about how their eyes feel and sometimes begin to rub their eyes. This has caused some people to erroneously conclude that their eye was injured. Furthermore, rubbing of the eyes can produce small scratches on the cornea resulting in painful irritated eyes.
The important point is that if your vision and eyes seem normal after direct laser beam exposure, then there is probably no significant damage to your eyes due to the laser beam. The U. If downloaded, the Amsler Grid on the first page should be printed so it is 10 x 10 cm, or 4 x 4 in. If you have spots that have not faded, or if you have any concern at all about effects or injuries from a laser incident, you should consult with a vision specialist.
For inspection of the eye and retina looking for damage , either of these two types of specialists would be fine: Ophthalmologist: This is a medical doctor specializing in the eye. Optometrist: This is an eye care specialist usually focused on glasses, contacts and routine eye care screening glaucoma, cataracts.
If your situation requires more specialized care, you may be referred to a retina specialist: Retina specialist: This is an ophthalmologist medical doctor who specializes in diseases and disorders of the retina. If the laser source involved in the alleged injury is available or known, is it capable of producing the observed clinical findings under the reported exposure conditions? The information below, about four general types of incidents and injuries, comes from a pamphlet, U. Additional commentary is from LaserPointerSafety.
Bright light experience. No pain. Note: infrared and ultraviolet laser beams are not visible and thus by definition cannot cause glare, dazzle or flashblindness. LPS Commentary: This is not cause for eye health concern. The only concern is if the bright light impairs a critical function, such as a pilot who is exposed to laser light on landing, or the driver of a motor vehicle. Minor injury Patient-reported symptoms: No or slight visual impairment.
Dark spot in field of vision. Eye exam results: Non-foveal retinal lesion s. The spot s are not located in the small central foveal vision area, but are elsewhere in the visual field. A soldier with these symptoms would be returned to duty without seeing a physician.
It is likely that such an injury would heal with no noticeable effect on normal vision. Serious injury Patient-reported symptoms: Vision impaired.
Large dark spot at or near center of vision. LPS Commentary: This is more serious because the spot is at or close to the center of vision. When we look directly at something, we are using foveal vision. Loss in this area is thus more serious.
Severe injury Patient-reported symptoms: Severe visual impairment. Large floating objects in eye. May see blood [visual field is red]. Eye exam results: Foveal retinal lesion s which may be obscured by vitreous hemorrhage. LPS Commentary: Such severe symptoms are unlikely to be caused by accidental, brief exposure to lasers generally available to consumers and the general public. Such injuries could be caused by deliberate staring exposure self-inflicted by a child or a drunk person.
There have been a very few severe injury incidents three times in 30 years at light shows when pulsed lasers were illegally and incorrectly used for audience scanning. Below are recommended levels to use when discussing vision loss. In , LaserPointerSafety. They stated the following: Symptoms and vision will probably improve over time.
The conservative approach would be to treat with oral NSAIDs non-steroidal anti-inflammatory drugs such as ibuprofen or indomethcin.
More aggressive therapy has been used, and outcomes are often good, only a small reduction in vision and small scotoma, in individual accident cases. Anti-VEGFs ranibizumab, bevacizumab, pegaptanib, and aflibercept injected in the eye have promise for some conditions that have similarities to laser eye damage.
The outcomes of these laser injuries may have been similar without treatment. The side effects of more aggressive treatment should be considered. Treatment should begin after the injury, ideally within the first day or two. Fortunately, since lesions seem to remain active for days or even weeks after the exposure, even late treatment -- starting days or even weeks later -- would still be beneficial.
Surgery should be reserved for more complicated cases. Stem cells are used and work for some corneal damage, but for the retina stem cells are for the future. Growing healthy retina to replace damaged retina is appealing and maybe someday that will be a standard treatment.
One or more follow-up exams should be scheduled. Currently, there is no proven treatment of retinal laser lesions except for surgical intervention vitrectomy for severe vitreous hemorrhage [retinal bleeding -- the patient would notice red in the visual field] NOTE: Retinal burns do not require eye patches. They only make the patient more disabled by taking away all of his vision; thus, further emphasizing his injury.
This would only be undertaken for massive injury which includes severe bleeding. The victim would see red in their visual field. Such a severe injury from laser pointers or audience exposure to light show lasers is extremely unlikely. Medical management of stress reactions for patients suffering from real or imagined laser injuries is like stress management of other injuries. The use of intravenous steroids in the acute setting to limit subsequent epiretinal and subretinal fibrosis is controversial and unproven to date.
Intravitreal injection of tissue thromboplastin activator TPA has been successful in removing subfoveal blood. The use of anti-inflammatory medication may enhance the initial recovery of vision and reduce the likelihood of longer term retinal complications from scarring and neovascularization. You may wish to share the study with your eye care professional.
While the FDA regulates the power of many laser pointers, many unregulated ones are still sold, and they can generate higher power levels. Even though you normally blink when a bright light shines in your eyes, there is still a chance of the light getting into your eye.
Serious problems can occur if the retina is damaged. Laser pointers can put out anywhere between 1 and 5 milliwatts of power, which is enough to damage the retina after 10 seconds of exposure. This can lead to permanent vision loss. That said, it can be very difficult to expose the retina to that much light for that long a time.
However, unregulated laser pointers can be of much stronger power, which means the eye would need to be exposed to the light for much less than 10 seconds to experience permanent damage. People experience this when the flash on a camera goes off, for example.
While people do regain their vision after a short time, it can still be dangerous if they are driving a car or flying a plane. While the chances of hurting your eyes with a laser pointer are not high, you should still exercise caution. This blog is for informational purposes only. For specific medical questions, please consult your physician.
To make an appointment with Dr. When you develop cataracts, your lifestyle can change dramatically. Sometimes, they can affect many of your body's other functions. Cochlear Implants. Hearing Aids. Hearing Aid Batteries. Hearing Aid Styles. Hearing Loss. Hearing Test. Types of Hearing Aids. Allergy Symptoms.
Allergy Testing. Allergy Treatment. Acid Reflux. Balloon Sinuplasty. Chronic Sinusitis. Deviated Septum and Septoplasty. Ear Infections and Ear Tube Surgery. The eye actually sees a small part of the electromagnetic spectrum that runs from short cosmic ray energies to long radiowaves. We see only from violet to red. Infrared IR and ultraviolet UV are just outside our ability to see.
The eye is most sensitive to yellow-green light nm. At the same power, nm red light is only 3 percent as bright. When determining safety limits for the laser pointer or in other areas, a value must be chosen.
Above a certain number is illegal or dangerous, below is OK. In real life many factors contribute to something becoming harmful. Look at traffic laws. Seventy miles per hour may be legal while 71 earns you a ticket, yet it is not really more dangerous. But mph is much riskier, and 50 mph may be dangerous if the road is covered with ice.
So with laser pointers, different conditions determine when retinal damage will actually occur. In FDA-regulated pointers, the laser power limit is set at one-tenth the actual threshold of damage.
If a person sees a bright light, they will automatically blink, on the average in less than 0. This is referred to as the blink reflex, and it is considered when the limit is assigned for how much power will cause an eye injury.
By the way, you shouldn't force a stare at a laser, just like you shouldn't stare at the sun or any bright light source. Possible more potentially damaging -- although not to the eye -- is that a regular pointer laser can overwhelm the eye with light, typically called flash blindness. If a person is walking a rocky path, operating machinery, a vehicle or aircraft, this temporary loss of vision could cause injury or disaster.
At night, when the pupil is most open, the effects would bemagnified. Some basic rules with lasers: Never direct a beam onto another person, especially their face. Do not shine it onto a mirror or mirror-like surface. Do not look at the beam through binoculars or a microscope.
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