For many people, laser eye surgery can correct their vision so they no longer need glasses or contact lenses. Laser eye surgery reshapes the cornea, the clear front part of the eye. This changes its focusing power.

There are different types of laser eye surgery. LASIK - laser-assisted in situ keratomileusis - is one of the most common. Many patients who have LASIK end up with 20/20 vision. But, like all medical procedures, it has both risks and benefits. Only your eye doctor can tell if you are a good candidate for laser eye surgery.

LASIK is corrective surgery to a very delicate part of the eye. Millions of people have had LASIK surgery to correct their vision, many with great success. But everyone is not a good candidate for the surgery.

LASIK Basics

If you wear glasses or contact lenses, you might think about surgery to correct your vision. In a LASIK procedure, a laser is used to reshape your cornea — the clear, round dome at the front of your eye — to improve the way your eye focuses light rays onto your retina. LASIK is shorthand for laser-assisted in situ keratomileusis.

Before you sign up for this surgery, here are a few things to think about:

• LASIK is surgery to a very delicate part of your eye, and cannot be reversed.
• As with any surgery, there are risks and possible complications.
• Millions of people have had LASIK, many very successfully, but it’s not for everyone.
• LASIK may not give you perfect vision. The American Academy of Ophthalmology (AAO) reports that nine out of 10 patients achieve somewhere between 20/20 and 20/40 vision, but 20/40 vision may not be sharp enough for certain work or leisure activities. Even 20/20 does not always mean perfect vision. Detailed, precise vision may be slightly diminished.
• Even with LASIK to correct your distance vision, you are likely to need reading glasses in your mid-40s. LASIK surgery cannot correct or prevent presbyopia, the age-related loss of focusing power for seeing near objects.
• If you are nearsighted and don't yet need reading glasses, having LASIK may mean you will need reading glasses earlier than if you had not had the surgery.
• The benefits of the LASIK procedure may diminish over time. More than 10 percent of LASIK patients in the U.S. require a second surgery, called “retreatment,” to restore the desired vision correction. This is more likely for people who were more nearsighted or farsighted, or had higher astigmatism before LASIK.
• Most insurance plans don’t cover the surgery.

Understanding Your Eyes

To see clearly, the cornea and the lens must bend, or refract, light rays so they focus on the retina — a layer of light-sensing cells that line the back of the eye. The retina converts the light rays into impulses that are sent to the brain, where they are recognized as images. If the light rays don’t focus on the retina, the image you see is blurry. This is called a refractive error. Glasses, contact lenses, and refractive surgery try to reduce these errors by making light rays focus on the retina.

Refractive errors are caused by an imperfectly shaped eyeball, cornea, or lens — or in the case of presbyopia, a lens that can't change shape enough to focus on close objects — and are of these basic types:

• myopia is another word for nearsightedness, where only nearby objects are clear or distinct
• hyperopia is another word for farsightedness, where only objects far away are clear or distinct
• astigmatism is when images are blurred, regardless of whether they are near or far
• presbyopia, or "aging eye," is a condition that typically develops between ages 40 and 50 and makes it more difficult to see very close. It can be corrected with bifocals or reading glasses, but usually can't be corrected by LASIK or some other refractive surgery.

Are You a Good Candidate for LASIK?

LASIK isn’t for everyone

• You should be at least 18 years old (21 for some lasers). The vision of people younger than 18 still is changing.
• You shouldn’t be pregnant or nursing. It might change the measured refraction of the eye.
• You shouldn’t be taking certain prescription drugs, like Accutane or oral prednisone.
• Your eyes must be healthy and your prescription stable. If you’re myopic, you should postpone LASIK until your refraction has stabilized. Myopia may continue to increase in some patients until their mid- to late 20s.
• Your general health should be good. LASIK may not be recommended for patients with diabetes, rheumatoid arthritis, lupus, glaucoma, herpes infections of the eye, cataracts, disorders of the cornea, and retinal disease. Discuss your general health status with your surgeon.
• A history of “dry eye” could matter. If you’ve had problems with dry eye, from wearing contact lenses, taking certain medications, or some other reason, talk to your eye doctor about how it could impact LASIK. You should be screened for dry eye before you have LASIK or other refractive surgery.

Other considerations

• The risks and rewards. If you’re happy wearing contacts or glasses, you may want to forgo the surgery.
• Your expectations from the surgery. Are they realistic? In general, having very poor eyesight reduces the chance of LASIK success and increases the chance of retreatment.
• Workplace requirements and lifestyle activities. Discuss work, sports, and recreation with your doctor to make sure LASIK is appropriate for you.
• If you're a candidate for monovision, which corrects one eye for distance vision and the other eye for near vision. LASIK cannot correct presbyopia so that one eye can see both near and far. However, it can be used to correct one eye for distance and the other for near vision. If you can adjust to this correction, it may eliminate or reduce your need for reading glasses. Yet monovision has its own risks:
  • After monovision, the two eyes no longer work together. This causes poorer quality vision and a decrease in depth perception. These effects are most noticeable in low lighting conditions and when performing tasks requiring very sharp vision.
  • As a result, you may need to wear glasses or contact lenses for distance or near vision when performing visually demanding tasks, such as driving at night, operating dangerous equipment, or performing occupational tasks requiring very sharp, close vision.

Finding a Surgeon

Only ophthalmologists are permitted to perform LASIK. Ask your ophthalmologist or optometrist for a referral to a medical doctor who performs LASIK. The can provide you with a list of its members who perform LASIK. About 95 percent of all ophthalmologists are AAO members.

Questions to ask your surgeon

• How long have you been doing LASIK surgery?
• How much experience do you have with the LASIK procedure?
• How do you define success? What’s your success rate? What is the chance for me (with my correction) to achieve 20/20? How many of your patients have achieved 20/20 or 20/40 vision? How many patients return for retreatments? (A five to 15 percent return is not unusual.)
• What laser will you be using for my surgery? Make sure the surgeon is using a laser approved by the U.S. Food and Drug Administration (FDA).
• What’s involved in after-surgery care?
• Who will handle my after-surgery care? Who will be responsible?
• What are the risks and possible complications?

Risks and Complications

Before the surgery, your surgeon should explain the risks and possible complications, including the pros and cons of having one or both eyes done on the same day. This is the “informed consent” process.

Risks

• Blindness and irreversible eye damage. In rare cases, errors during surgery (like the malfunctioning of the laser device) or complications after surgery (for example, inflammation) may cause irreversible damage to the eye, including permanent blindness. In other cases, the problems can be corrected with additional surgeries or other treatments.
• Vision loss. You may not see as well after the surgery — even with glasses or contacts — as you did with glasses or contacts before the surgery. Or, you may need glasses or contacts to see as well as you did before surgery.
• Severe night vision problems. You may develop debilitating visual symptoms, particularly glare, halos, and/or double vision that can seriously affect nighttime vision.
• Decrease in contrast sensitivity, “crispness,” or sharpness. Objects may appear fuzzy or grayish. Even with good vision on the vision chart, you may not see as well in situations of low contrast — like at night or in fog — after treatment compared to before.
• Severe dry eye syndrome. As a result of surgery, your eye may not be able to produce enough tears to keep it moist and comfortable. Dry eye not only causes discomfort, but can reduce visual quality due to intermittent blurring and other visual symptoms. This condition may be permanent. Intensive drop therapy and use of plugs or other procedures may be required.

Complications

• Corneal infection or inflammation. These problems may require additional surgery or other treatments.
• Problems with the corneal flap after surgery. These include irregular or incomplete flaps, ingrowth of cells under the flap that may need to be surgically removed, and irregular healing that results in a distorted cornea, which can only be corrected with a corneal transplant.

What to Expect Before, During, and After Surgery

Before

You’ll need a complete eye examination by your refractive surgeon. Your referring eye care professional may perform a preliminary eye exam. Take your eye prescription records with you to the exams. If you wear contact lenses, stop wearing them before your baseline evaluation (soft contact lenses — two weeks; toric soft lenses or rigid gas permeable lenses — three weeks; hard lenses — four weeks). Contacts can temporarily change the shape of the cornea and compromise precise measurements in the pre-op exam.

Your doctor should:

• dilate your pupils to fine-tune your prescription
• examine your eyes to make sure they’re healthy, including testing for glaucoma, performing a retinal exam, and assessing for dry eye
• take the following measurements:
  • the curvature of your cornea and your pupils
  • the topography of your eyes, to make sure you don’t have an irregular astigmatism or a cone-shaped cornea — a condition called keratoconus
  • the thickness of your cornea. You need to have enough tissue left after your corneas have been cut and reshaped.
• ask you to sign an informed consent form after a thorough discussion of the risks, benefits, options, and possible complications of LASIK surgery. Review the form carefully, and don’t sign until you understand everything in the form.

If your doctor doesn’t think LASIK is right for you, you might consider getting a second opinion; however, if the opinion is the same, believe it.

If you qualify for surgery, your doctor may tell you to stop wearing your contact lenses for a while before the surgery for the same reason that you stopped wearing them before your baseline exam: contacts can temporarily change the shape of the cornea. Your cornea should be in its natural shape the day of surgery. Your doctor also may tell you to stop wearing makeup, lotions, or perfume for a few days before surgery. These products can interfere with the laser treatment or increase the risk of infection after surgery.

During

LASIK is an outpatient surgical procedure. The only anesthetic is an eye drop that numbs the surface of the eye. The surgery takes 10 to 15 minutes for each eye. Sometimes, both eyes are done during the same procedure; but sometimes, surgeons wait (sometimes days or weeks) to see the result on one eye before doing surgery on the other.

The Surgical Procedure: The eye is moistened. A suction ring is positioned to keep the eye from moving and the cornea in the correct position. A special device cuts a hinged flap of thin corneal tissue off the outer layer of the eyeball (cornea) and the flap is lifted out of the way. The laser reshapes the underlying corneal tissue, and the surgeon replaces the flap, which quickly adheres to the eyeball. There are no stitches. A shield — either clear plastic or perforated metal — is placed over the eye to protect the flap.

After

Healing is relatively fast, but you may want to take a few days off from work after the surgery. Avoid sports for three days after surgery; impact sports or similar activities for four weeks. Be aware that:

• you may experience a mild burning or sensation for a few hours after surgery. Don’t rub your eye. Your doctor can prescribe a painkiller, if you need one, to ease any discomfort.
• your vision probably will be blurry the day of surgery, but it should improve considerably by the next day when you return for a follow-up exam
• you should report aggravating or unusual side effects to your doctor immediately
• you shouldn’t drive until your vision has improved enough to do so safely
• you should avoid swimming, hot tubs, and whirlpools for two weeks after surgery

Surgical Alternatives to LASIK

You may want to discuss some surgical alternatives to LASIK with your eye doctor. In general, these procedures are relatively new and are performed less often than traditional LASIK surgery.

Photorefractive Keratectomy (PRK)

In surgery using PRK, including Epi-LASIK and LASEK, surgeons use lasers to create “surface ablations” on the cornea without creating a corneal flap. Because these procedures cut only the very top (epithelial) layer of the cornea, the risk of certain complications associated with LASIK surgery may be reduced.

Conductive Keratoplasty (CK)

This is a thermal refractive surgery procedure used to correct mild to moderate farsightedness (hyperopia) in people over age 40 by use of a tiny probe that releases controlled amounts of radio frequency (RF) energy, instead of a laser, to apply heat to the peripheral portion of the cornea. Farsightedness may return over time.

Phakic Intraocular Lens (IOL)

An IOL is a form of contact lens that is surgically implanted inside the eye in front of the lens. These implants are used to correct vision problems caused by cataracts and other refractory problems that are too severe to be corrected with corneal-based refractive surgery. Certain types of IOLs, such as Multifocal or accommodative lenses, may not only improve distance vision but also eliminate the need for reading glasses.

The eye and vision errors

The cornea is a part of the eye that helps focus light to create an image on the retina. It works in much the same way that the lens of a camera focuses light to create an image on film. The bending and focusing of light is also known as refraction. Usually the shape of the cornea and the eye are not perfect and the image on the retina is out-of-focus (blurred) or distorted. These imperfections in the focusing power of the eye are called refractive errors. There are three primary types of refractive errors: myopia, hyperopia and astigmatism. Persons with myopia, or nearsightedness, have more difficulty seeing distant objects as clearly as near objects. Persons with hyperopia, or farsightedness, have more difficulty seeing near objects as clearly as distant objects. Astigmatism is a distortion of the image on the retina caused by irregularities in the cornea or lens of the eye. Combinations of myopia and astigmatism or hyperopia and astigmatism are common. Glasses or contact lenses are designed to compensate for the eye's imperfections. Surgical procedures aimed at improving the focusing power of the eye are called refractive surgery. In LASIK surgery, precise and controlled removal of corneal tissue by a special laser reshapes the cornea changing its focusing power.

Other types of refractive surgery

Radial Keratotomy or RK and Photorefractive Keratectomy or PRK are other refractive surgeries used to reshape the cornea. In RK, a very sharp knife is used to cut slits in the cornea changing its shape. PRK was the first surgical procedure developed to reshape the cornea, by sculpting, using a laser. Later, LASIK was developed. The same type of laser is used for LASIK and PRK. Often the exact same laser is used for the two types of surgery. The major difference between the two surgeries is the way that the stroma, the middle layer of the cornea, is exposed before it is vaporized with the laser. In PRK, the top layer of the cornea, called the epithelium, is scraped away to expose the stromal layer underneath. In LASIK, a flap is cut in the stromal layer and the flap is folded back.

Another type of refractive surgery is thermokeratoplasty in which heat is used to reshape the cornea. The source of the heat can be a laser, but it is a different kind of laser than is used for LASIK and PRK. Other refractive devices include corneal ring segments that are inserted into the stroma and special contact lenses that temporarily reshape the cornea (orthokeratology).

Ablate - in surgery, is to remove.

Ablation zone - the area of tissue that is removed during laser surgery.

Accommodation - the ability of the eye to change its focus from distant objects to near objects.

Acuity - clearness, or sharpness of vision.

All-Laser LASIK - (also known as “Bladeless LASIK”) a laser keratome device is used to cut a corneal flap for LASIK surgery.

Astigmatism - a distortion of the image on the retina caused by irregularities in the cornea or lens.

Cornea - the clear, front part of the eye. The cornea is the first part of the eye that bends (or refracts) the light and provides most of the focusing power.

Diopter - the measurement of refractive error. A negative diopter value signifies an eye with myopia and positive diopter value signifies an eye with hyperopia.

Dry Eye Syndrome - a common condition that occurs when the eyes do not produce enough tears to keep the eye moist and comfortable. Common symptoms of dry eye include pain, stinging, burning, scratchiness, and intermittent blurring of vision.

Endothelium - the inner layer of cells on the inside surface of the cornea.

Epithelium - the outermost layer of cells of the cornea and the eye's first defense against infection.

Excimer laser - an ultraviolet laser used in refractive surgery to remove corneal tissue.

Farsightedness - the common term for hyperopia.

FDA - the abbreviation for the Food and Drug Administration. It is the United States governmental agency responsible for the evaluation and approval of medical devices.

Flap & Zap - a slang term for LASIK.

Ghost Image - a fainter second image of the object you are viewing.

Glare - scatter from bright light that decreases vision.

Halos are rings around lights due to optical imperfections in or in front of the eye.

Haze - corneal clouding that causes the sensation of looking through smoke or fog.

Higher order aberrations refractive errors, other than nearsightedness, farsightedness, and astigmatism, that cannot be corrected with glasses or contacts.

Hyperopia - the inability to see near objects as clearly as distant objects, and the need for accommodation to see distant objects clearly.

Inflammation - the body's reaction to trauma, infection, or a foreign substance, often associated with pain, heat, redness, swelling, and/or loss of function.

Informed Consent Form a document disclosing the risks, benefits, and alternatives to a procedure.

In Situ a Latin term meaning "in place" or not removed.

Iris - the colored ring of tissue suspended behind the cornea and immediately in front of the lens.

Keratectomy - the surgical removal of corneal tissue.

Keratotomy - a surgical incision (cut) of the cornea.

Keratitis - inflammation of the cornea.

Kerato - prefix indicating relationship to the cornea.

Keratoconus a disorder characterized by an irregular corneal surface (cone-shaped) resulting in blurred and distorted images.

Keratomileusis - carving of the cornea to reshape it.

Laser - the acronym for light amplification by stimulated emission of radiation. A laser is an instrument that produces a powerful beam of light that can vaporize tissue.

Laser Keratome - a laser device used to create a corneal flap

LASIK - the acronym for laser assisted in situ keratomileusis which refers to creating a flap in the cornea with a microkeratome and using a laser to reshape the underlying cornea.

Lens - a part of the eye that provides some focusing power. The lens is able to change shape allowing the eye to focus at different distances.

Microkeratome - a mechanical surgical device that is affixed to the eye by use of a vacuum ring. When secured, a very sharp blade cuts a layer of the cornea at a predetermined depth.

Monovision - the purposeful adjustment of one eye for near vision and the other eye fordistance vision.

Myopia - the inability to see distant objects as clearly as near objects.

Nearsightedness - the common term for myopia.

Ophthalmologist - a medical doctor specializing in the diagnosis and medical or surgical treatment of visual disorders and eye disease.

Optician - an expert in the art and science of making and fitting glasses and may also dispense contact lenses.

Optometrist - a primary eye care provider who diagnoses, manages, and treats disorders of the visual system and eye diseases.

Overcorrection - a complication of refractive surgery where the achieved amount of correction is more than desired.

PRK - the acronym for photorefractive keratectomy which is a procedure involving the removal of the surface layer of the cornea (epithelium) by gentle scraping and use of a computer-controlled excimer laser to reshape the stroma.

Presbyopia - the inability to maintain a clear image (focus) as objects are moved closer. Presbyopia is due to reduced elasticity of the lens with increasing age.

Pupil - a hole in the center of the iris that changes size in response to changes in lighting. It gets larger in dim lighting conditions and gets smaller in brighter lighting conditions.

Radial Keratotomy - commonly referred to as RK; a surgical procedure designed to correct myopia (nearsightedness) by flattening the cornea using radial cuts.

Refraction - a test to determine the refractive power of the eye; also, the bending of light as it passes from one medium into another.

Refractive Errors - imperfections in the focusing power of the eye, for example, hyperopia, myopia, and astigmatism.

Refractive Power - the ability of an object, such as the eye, to bend light as light passes through it.

Retina - a layer of fine sensory tissue that lines the inside wall of the eye. The retina acts like the film in a camera to capture images, transforms the images into electrical signals, and sends the signals to the brain.

Sclera - the tough, white, outer layer (coat) of the eyeball that, along with the cornea, protects the eyeball.

Snellen Visual Acuity Chart - one of many charts used to measure vision.

Stroma - the middle, thickest layer of tissue in the cornea.

Undercorrection - a complication of refractive surgery where the achieved amount of correction is less than desired.

Visual Acuity - the clearness of vision; the ability to distinguish details and shapes.

Vitreous Humor - the transparent, colorless mass of gel that lies behind the lens and in front of the retina and fills the center of the eyeball.

Wavefront - a measure of the total refractive errors of the eye, including nearsightedness, farsightedness, astigmatism, and other refractive errors that cannot be corrected with glasses or contacts.

Laser treatment, also called photocoagulation, creates tiny burns inside the eye with a beam of light. This method treats leaky blood vessels and extra fluid, called edema. Your doctor usually provides this treatment during several office visits, using medicine to numb your eyes. Laser treatment can keep eye disease from getting worse, which is important to prevent vision loss or blindness. But laser treatment is less likely to bring back vision you’ve already lost compared with anti-VEGF medicines.

There are two types of laser treatment

• Focal/grid laser treatment works on a small area of the retina to treat diabetic macular edema.
• Scatter laser treatment, also called panretinal photocoagulation (PRP), covers a larger area of the retina. This method treats the growth of abnormal blood vessels, called proliferative diabetic retinopathy.

The use of an intense beam of light, such as a laser, to seal off blood vessels or destroy tissue. It is used to treat certain eye conditions, and may be used to destroy blood vessels that a tumor needs to grow.

Light Coagulation

The coagulation of tissue by an intense beam of light, including laser (LASER COAGULATION). In the eye it is used in the treatment of retinal detachments, retinal holes, aneurysms, hemorrhages, and malignant and benign neoplasms.

Laser Coagulation

The use of green light-producing LASERS to stop bleeding. The green light is selectively absorbed by HEMOGLOBIN, thus triggering BLOOD COAGULATION.

Laser therapy uses an intense, narrow beam of light to remove or destroy cancer and abnormal cells that can turn into cancer. Tumor cells absorb light of different wavelengths (or colors) than normal cells do. So, tumor cells can be targeted by selecting the proper wavelength of the laser. Laser therapy is a type of local treatment, which means it treats a specific part of your body.

Lasers can also be used in other types of local treatment, including photodynamic therapy and a treatment that is like hyperthermia, called laser interstitial thermal therapy, or LITT.

Laser therapy can also be used with surgery. Doctors can use lasers to seal:

• nerve endings after surgery, which reduces pain
• lymph vessels after surgery, which helps reduce swelling and limit the spread of cancer cells
• blood vessels during surgery, which reduces bleeding

Diabetic retinopathy is an eye condition that can cause vision loss and blindness in people who have diabetes. It affects blood vessels in the retina (the light-sensitive layer of tissue in the back of your eye).

If you have advanced diabetic retinopathy, your doctor may use a type of laser treatment called scatter laser surgery as part of your treatment plan. In scatter laser surgery (sometimes called panretinal photocoagulation), your doctor will use a medical laser to shrink blood vessels in your eye that are causing vision problems.

You may also need other treatments, like injections, in addition to laser treatments.

What can I expect from laser treatment?

You can get this laser treatment at your eye doctor’s office. Your eye doctor will:

• Put numbing medicine in your eye
• Aim a laser into your eye using a special lens

During the treatment, you may see flashes of light and your eye may sting or feel uncomfortable. Your vision will be blurry for the rest of the day, so you’ll need someone to drive you home. You may need more than 1 session of scatter laser surgery.

Is laser treatment right for me?

Like any surgery, this treatment has risks. It can cause loss of peripheral (side) vision, color vision, and night vision. But for many people, the benefits of this treatment outweigh the risks.

Talk with your doctor to decide if scatter laser surgery is right for you.

Surgeons must have special training before they can do laser therapy and strict safety measures must be followed. Laser therapy is expensive and requires specialized equipment. Also, the effects of laser therapy may not last long, so doctors may have to repeat the treatment for you to get the full benefit.

Not every hospital or cancer center in the country has skilled doctors and the machines needed to use lasers in cancer treatment. Talk with your doctor or contact hospitals and cancer centers in your area to find out if they are using lasers.

The retina (a light-sensitive layer of tissue at the back of your eye) can sometimes develop a small hole or tear because of aging, certain illnesses, or an eye injury. If you have a retinal tear, you may need treatment to prevent a retinal detachment — a medical emergency where the retina is pulled away from its normal position.

There are 2 ways that your eye doctor can fix holes or tears in your retina:

• Laser surgery (photocoagulation)
• Freeze treatment (cryopexy)

If your eye doctor finds a tear or small hole in your retina, they can use one of these treatments to prevent your retina from detaching. Which treatment you’ll need depends on the location of the tear in your retina. You can get these treatments at your eye doctor’s office.

Doctors also use these treatments as part of surgery to repair a detached retina.

Laser surgery (photocoagulation)

With this treatment, your doctor will shine a medical laser inside your eye and make small burns around the tear or hole in your retina. The burns create small scars that fix the tear and help hold your retina in place.

When you get this treatment, your doctor will:

• Put numbing medicine in your eye
• Shine the laser through the pupil of your eye to seal the tear in your retina

You may see a flashing light when your doctor uses the laser.

After this treatment, your doctor may give you special eye drops to help keep your eye from swelling. You may need to avoid some activities, like vigorous exercise or heavy lifting, while your eye heals.

Freeze treatment (cryopexy)

Another way your doctor can treat a tear or hole in your retina is by using a freezing probe (a small tool that gets very cold) directly over the tear on the white outside part of your eye (the sclera). The cold from the freezing probe makes a scar form around the tear in your retina and helps keep it in place.

When you get this treatment, your doctor will:

• Put numbing medicine in your eye
• Touch the white part of your eye closest to the tear in your retina with a freezing probe

You may feel some cold or pressure when your doctor uses the freezing probe.

After this treatment, your doctor may give you special eye drops to help keep your eye from swelling. You may need to avoid some activities, like vigorous exercise or heavy lifting, while your eye heals.

Laser treatment can help treat some types of glaucoma. It’s a procedure that your eye doctor can do in the office. It works by helping the fluid in your eye drain, which can help lower the pressure inside your eye. Ask your eye doctor if laser treatment is right for you.

Do I need laser treatment for my glaucoma?

A laser treatment called trabeculoplasty (tra-BECK-you-low-plas-tee) is used to treat open-angle glaucoma. There are other types of laser treatment that can treat other types of glaucoma.

Ask your eye doctor about all your glaucoma treatment options, including medicines, laser treatment, and surgery. You and your doctor can work together to make a treatment plan that’s right for you.

What happens during laser treatment for glaucoma?

When you get laser treatment, your doctor will:

• Put drops in your eye to make it numb
• Aim a laser (a strong beam of light) into your eye using a special lens
• Use the laser to try to help fluid drain from your eye

You may see flashes of bright green or red light during the treatment. Most people feel little or no pain or discomfort during the treatment.

If you have glaucoma in both eyes, your doctor may treat both eyes on the same day — or they may treat 1 eye and schedule treatment for your other eye a few days or a few weeks later.

Are there any side effects?

Laser treatment can cause side effects, just like any procedure.

You may have some swelling or soreness. Sometimes the laser can scratch the cornea (the clear front layer of the eye) or make the cornea very dry. This can be painful, but the pain usually goes away quickly as the cornea heals. Your doctor can give you eye drops to help.

How long does it take to recover?

Most people can go back to their normal daily activities the day after their laser treatment.

Right after the treatment, your eye may be irritated and your vision might be blurry, so you’ll need someone to give you a ride home from the doctor’s office.

Will I need more treatment?

Laser treatment works very well for most people, but it doesn’t work for everyone. You’ll need to wait 4 to 6 weeks to find out if the treatment worked.

Most people will need to keep taking glaucoma medicine even after laser treatment. You’ll also need a few follow-up visits so your doctor can check your eye pressure.

Because the treatment wears off over time, some people may need to get laser treatment more than once. Your doctor may also suggest other treatment, like glaucoma surgery.

When cutting tissue, lasers seal the cut from bleeding, so they may cause less damage to normal tissues when used in surgery. As a result, you usually have less pain, bleeding, swelling, and scarring. With laser therapy, the time in surgery is usually shorter. In fact, laser therapy can often be done on an outpatient basis. It takes less time to heal after laser surgery, and you are less likely to get an infection.

What is a laser?

Laser stands for Light Amplification by the Stimulated Emission of Radiation. One basic type of laser consists of a sealed tube, containing a pair of mirrors, and a laser medium that is excited by some form of energy to produce visible light, or invisible ultraviolet or infrared radiation.

There are many different types of lasers and each uses a different type of laser medium. Common laser media include gases such as argon or a helium and neon mixture, solid crystals such as ruby, and liquid dyes or chemicals. When energy is applied to the laser medium, it becomes excited and releases energy as particles of light (photons).

A pair of mirrors at either end of the sealed tube either reflects or transmits the light (see illustration below) in the form of a concentrated stream called a laser beam. Each laser medium produces a beam of a unique wavelength and color.

Laser

What are lasers used for?

Lasers are used for a variety of purposes including pointing out objects during a presentation, aligning materials at construction sites and in the home, and by doctors for cosmetic and surgical procedures. Many items you encounter on a daily basis use lasers, including CD and DVD players; bar code scanners; dental drills; laser-guided tools, such as levels; and laser pointers.

Why are lasers uniquely hazardous?

Two characteristics of laser light contribute to the hazard:

• Laser light can be emitted in a tight beam that does not grow in size at a distance from the laser. This means that the same degree of hazard can be present both close to and far from the laser.
• The eye can focus a laser beam to a very small, intense spot on its retina, which can result in a burn or blind spot.

What do you mean by laser “radiation?” Does it go through the body or cause cancer?

Some lasers emit radiation in the form of light. Others emit radiation that is invisible to the eye, such as ultraviolet or infrared radiation. In general, laser radiation is not in itself harmful, and behaves much like ordinary light in its interaction with the body. Laser radiation should not be confused with radio waves, microwaves, or the ionizing x-rays or radiation from radioactive substances such as radium.

Are all lasers legal for consumer use?

No. Some lasers are strictly for use by medical, industrial, or entertainment professionals and should only be used by a person with appropriate training and licenses.

The FDA requires labels on most laser products that contain a warning about the laser radiation and other hazards, and a statement certifying that the laser complies with FDA safety regulations. The label must also state the power output and the hazard class of the product. Consumer laser products are generally in classes I, II, and IIIa, while lasers for professional use may be in classes IIIb and IV.

What do the different classifications of lasers mean?

Laser Hazard Classes

The Food and Drug Administration (FDA) recognizes four major hazard classes (I to IV) of lasers, including three subclasses (IIa, IIIa, and IIIb). The higher the class, the more powerful the laser and the potential to pose serious danger if used improperly. The labeling for Classes II–IV must include a warning symbol that states the class and the output power of the product. Approximate IEC equivalent classes are included for products labeled under the classification system of the International Electrotechnical Commission.

What are laser pointers?

Laser pointers are tools used for pointing out objects or locations, and are defined as "surveying, leveling, and alignment laser products" in an FDA regulation. They are commonly used during lectures and astronomy presentations, and laser pointers incorporated into spirit levels and hand tools are also very popular. In recent years laser pointers have become readily available, and are commonly sold in hardware, pet, hobby, and office supply stores.

Are laser pointers safe?

When used properly lasers pointers pose minimal risk if they meet laser power limits. Laser pointers are misused when they are directed at the eyes or treated as toys. The light energy from a laser pointer aimed into the eye can be more damaging than looking directly into the sun. In addition, the startling effect of a bright beam of light aimed at someone driving a car or operating other machinery can cause serious accidents.

The FDA is concerned about the increased availability of a variety of laser products that may be used unsafely. Green, blue and violet laser pointers have the agency particularly concerned. While there are legitimate uses for these laser pointers, they may be altered to become more powerful and unsafe if not used responsibly.

Is the brightness of the laser light a good indicator of its power and eye hazard?

No. Never assume the color brightness of a laser beam indicates its power.  In lighted conditions (indoors or outdoors), a beam from a powerful laser can appear to be the same brightness or dimmer than the beam of a less powerful laser. For example in the photo below, the green laser beam appears much brighter than the red and far brighter than the blue.  These are actually equally powered lasers and all three present the same eye hazard from looking into the beam. If you see a bright blue or violet laser beam with brightness similar to a green laser, you can safely assume that the blue/violet laser light is far more powerful and looking directly into the beam will cause severe and immediate eye damage.

As a rule, you should never look directly into any laser beam.

What is the proper use of a laser pointer?

Remember, laser pointers are not toys and they should only be used by an adult, or with adult supervision.

• Never aim or shine a laser pointer at anyone.
• Only activate the laser pointer when you are using it to point at a nearby object.
• Do not buy laser pointers for your children. Lasers are not toys.
• Before purchasing a laser pointer, make sure it has the following information on the label:
  • a statement that it complies with Chapter 21 CFR (the Code of Federal Regulations)
  • the manufacturer or distributor's name and the date of manufacture
  • a warning to avoid exposure to laser radiation
  • the class designation, ranging from Class I to IIIa. Class IIIb and IV products should be used only by individuals with proper training and in applications where there is a legitimate need for these high-powered products.

What is FDA’s role in regulating lasers?

The FDA regulates both medical and non-medical lasers. The FDA may inspect manufacturers of laser products and require the recall of products that don't comply with federal standards or that have radiation safety defects. The agency also may test laser products and inspect displays of laser light shows to ensure the public is protected. Producers of laser light shows are required to tell the FDA where they are planning a show so that the agency can inspect it if possible and take action if required.

FDA is currently working to identify manufacturers of overpowered green laser pointers and other illegal lasers, and is taking action to prevent these unsafe products from being sold in the United States.

L-A-S-E-R stands for Light Amplification by Stimulated Emission of Radiation. Through a complicated electronic process, a beam of light is produced which has special properties. This light is all one wavelength; that is, it is all one color of the spectrum. The light is focused so that all of its rays are traveling in the same direction. In a similar fashion, you might use the lens of a magnifying glass to focus rays of sunlight to a point.

Lasers are used for many reasons. In many instances, lasers can improve the precision of the surgeon with finely focused beams of light. Some lasers can reduce bleeding by coagulating blood vessels as they cut tissue. Others can be aimed down narrow passages or sent down fiber-optic channels in endoscopes to reach areas that are otherwise inaccessible.

A new trend in laser surgery is to use the special properties of different wavelengths of laser light to selectively treat different problems. For instance, a yellow laser light absorbed by the red blood cells of a birthmark called a "portwine stain" can result in the selective destruction of the birthmark without affecting the skin cells around it. The result is that scarring of the remaining normal skin is lessened or avoided. In another instance of selective laser treatment, drugs that are retained by tumors are infused into the body and activated by lasers to destroy only the tumor, preserving normal structures.

In many instances, the cost of medical care can be reduced by lasers. Through their use, many procedures that previously required hospital admission can be done on an outpatient basis.

Fragmentation of CALCULI, notably urinary or biliary, by LASER.

Wrinkles can be reduced using friction or they can be ‘plumped out’ with a variety of technologies. Laser skin resurfacing uses a laser beam to burn the skin. Injectable fillers can be used in small doses to paralyse the underlying muscles responsible for forming the skin wrinkles. This can be a safe and effective temporary treatment for fine facial lines and wrinkles.

Injections of fat or collagen can be piped along wrinkles to smooth them out. Botulinum toxin Type A (available in Australia under the brand names Botox® or Dysport®) is sometimes used to treat frown lines between the eyebrows.

Laser treatment can cause side effects, just like any procedure.

You may have some swelling or soreness. Sometimes the laser can scratch the cornea (the clear front layer of the eye) or make the cornea very dry. This can be painful, but the pain usually goes away quickly as the cornea heals. Your doctor can give you eye drops to help.