Laser Surgery of the Eye
What is laser surgery of the eye?
L.A.S.E.R. is an acronym or a word that is created from its meaning that stands for what it is or does, in this case:
“Light Amplification by Stimulated Emission of Radiation”
The name and color of the laser depends upon the special material from which it is derived:
Argon fluoride (Excimer) = Ultraviolet (invisible) light
YAG (yttrium-aluminum-garnet) ultraviolet (invisible) light
Argon gas = blue –green light
Krypton gas = red or yellow light
Lasers have been used in ophthalmology to treat several different types of eye disease.
How does laser work?
There are two different ways that laser are used to treat eye diseases:
1. Thermal (heat transfer to eye tissues)
2. Photo-disruption(light manipulation of eye tissues)
Thermal lasers (Argon and Krypton)
The light of these lasers is converted to heat when it reaches the tissue of the eye. The heat is used to do one of several things to treat eye disease:
– Seal blood vessels (veins and arteries) that are bleeding or leaking fluid;
– Destroy abnormal tissues such as a tumor;
– Bond the retina to the back of the eye to prevent a retinal detachment;
– Open the eyes drainage system to prevent otpic nerve damage from elevated eye pressure;
– Create an opening in the iris (the colored portion of the eye) for the prevention or treatment of narrow angle glaucoma.
Photo-Disruptive/light manipulation lasers (YAG and Excimer)
The light of these lasers cut through the eye tissues like a knife. The energy of this light is used to:
– Cut thin membranes that cause blurry vision that may grow on the artificial lenses that are placed in the eye after cataract surgery.
– Reshape (or sculpt) the surface of the eye (cornea) so patients don’t have to wear glasses.
What is the advantage of treating the eye with lasers?
– The surgery is often performed in an outpatient setting. This allows you to go home right after the procedure is completed.
– The eye surgeon has great precision when performing the procedure.
– There is no risk of infection from laser light because the outside of the eye is never actually affected.
Which eye diseases are treated with laser surgery?
1. Laser after cataract surgery
2. Laser refractive surgery
3. Laser glaucoma
4. Laser retinal surgery
a. Retinal tears or holes
b. Diabetic retinopathy
c. Macular degeneration
d. Retinal vein occlusions
e. Infections (Histoplasmosis)
After Cataract Surgery: Cataract surgery involves the removal of the “darkened or opacified” middle portion of the lens of the eye from its’ capsule (like removing the portion of the orange fruit we eat from its’ peel). The capsule (or peel) remains in place in the eye, and the artificial lens is placed inside the capsular peel. Because the capsular peel remains a living part of the eye, after surgery it sometimes growa thin skin that causes the vision to become blurry. This thin skin or vision clouding membrane can be opened in the middle with the YAG laser, removing the cause of the cloudy/blurry vision.
Laser refractive surgery: With LASIK (LAser in SItu Keratomileusis), the Exicmer laser is used to reshape (or sculpt) the corneal surface of theeye to refocus light or images that we see like glasses or contact lenses does thereby eliminating the need for the glasses or contact lenses.
Laser Glaucoma surgery:This is a disease caused by increased fluid pressure in the eye that damages the optic nerve. The optic nerve sends the picture or images that the eye captures like a camera to the brain allowing us to see. Glaucoma is the second (2nd) most common cause of blindness in the United States, and the #1 cause of blindness of African Americans.
Loss of vision from glaucoma can often be prevented by your ophthalmologist if it is discovered early in the process before significant damage to the optic nerve. Therefore, early detection and treatment can save vision. Eye drops and pills that lowers pressure is the usual way that this disease is treated. If this treatment does not adequately lower the pressure inside the eye, laser surgery may be used to lower the pressure. This occurs by increasing the natural drainage of fluid from inside the eye, thereby decreasing the pressure in the eye. Sometimes laser surgery can be used early in the glaucoma diseasetreatment process to lower the pressure especially when the patient cannot tolerate eye drops due to allergic reactions, or when it is difficult to comply with the use of several eye drops most of which need to be placed in the eye multiple times daily for them to work properly.
The retina is the inner layer of the eye that senses light and captures images much like the film of a camera captures images. The image or picture that is captured by the retina is sent to the brain by way of the optic nerve allowing us to see. If the retina tears, it can separate from the back wall of the eye (much like wallpaper can coming off the wall). This is known as a retinal detachment, and can cause the loss of sight.
Symptoms of retinal tears include:
-Sudden flashes of light
– Floaters or “spider webs” in the vision
– Specks or small spots in the vision
Most retinal tears can be treated with the argon or krypton laser if they are found early before the retina can detach. The laser actually bonds the retina to the back eye wall around the tear, break or retinal hole (like pasting or nailing the wallpaper back t the wall). Sealing this defect stops fluid from inside the eye from getting behind the retina causing the detachment. If the detachment has already occurred, the laser is often used as a part of the surgical repair of the retina to help reattach it to the back eye wall.
Diabetic Retinopathy: Eye disease from diabetes is a major cause of visual loss. Diabetes can cause damage to blood vessels that result in leakage and swelling of the most sensitive area in the retina called macula edema. It can also cause bleeding in the retina. In advanced diabetic eye disease, abnormal blood vessels can continue to grow, break and bleed causing severe loss of vision known as proliferative diabetic retinopathy.
Laser surgery for Diabetic Retinopathy:
– Seals leaking/bleeding blood vessels to reduce macular swelling, helping to prevent further visual loss.
– Stops or slows the growth of abnormal blood vessels, diminishing the chance of bleeding and scarring in the eye.
Age Related-macularDegeneration (AMD):
There are two kinds of AMD referred to as dry and wet.
Dry AMD: The macula is the central area of the retina that allows us to see very fine details like small print clearly. Macular degeneration affects the center of your vision causing difficulty with visual task such as reading or threading a needle.
Most people have “dry” macular degeneration, which means there is no bleeding or other fluid causing swelling in the macula. Dry macular degeneration cannot be helped by laser surgery.
Wet AMD: Fewer people have wet age-related macular degeneration than the dry kind. With this condition, abnormal blood vessels grow into abnormal areas of the macula, break and bleedthereby causing swelling and often leaves scarred tissue in the macula. In certain cases, this can be treated with argon or krypton laser. The laser seals the abnormal bleeding blood vessels to prevent additional damage.
Other retinal problems treated with retina lasers:
-Retina vein occlusion
– Retinal infections (like Histoplasmosis)
– Central serous chorio-retinopathy (CSCR)
(Acuteswelling g in the macula area often seen in young to middle aged adults)
– Tumors of the eye
Laser surgery is one of the great advances in the treatment of eye disease. How successful the laser treatment is depends on the type of eye disease that is treated.
In most instances laser treatment can prevent the progression and stop further visual loss, but this may not provide great improvement in the vision. In many situations that include the use of the YAG laser after cataract surgery the vision may improve considerably.
At FERST Eye Institute, we will discuss the risks, benefits and alternatives of laser treatment that may be available to treat your eye problem.