Laser surgery has been one of the great advances in treating eye diseases. The success of laser depends on the type of eye disorder.
In most situations, laser surgery helps prevent further loss of sight, but will not provide great improvement in vision. In few situations, such as YAG laser surgery or PRK, vision may be restored to normal.
Laser surgery in ophthalmology can successfully treat many types of eye diseases.
What Is LASER?
The word laser stands for " L ight A mplification by S timulated E mission of R adiation." A laser is a concentrated monochromatic, coherent beam of light, created when an electric current passes through a special material.
The name and the color of the laser depend on the type of special material that is used:
- Argo gas - blue-green light
- Krypton gas - red or yellow light
- YAG (yttrium-aluminum-garnet) - invisible infrated light
- Argon-fluoride (excimer) - invisible ultraviolet light
How does Laser work?
There are two diiferent ways that lasers are used to treat eye diseases
Thermal Lasers
The light is converted to heat when it reaches the eye
- Seal blood vessels(veins and arteries) that are bleeding or leaking fluids
- Destroy abnormal tissue such as a tumor
- Bond the retina to the back of the eye
- Open the eye's filtration system for glaucoma treatment
Photodisruptive Lasers
The light cuts or sculpts the tissue, similar to a knife.
The beam of light is used to:
- Create an opening in the iris for treatment of narrow angle glaucoma
- Cut thin membranes inside the eye that are blocking vision
- Change the shape of the eye's surface
What are the advantages of using ophthalmic lasers?
Laser surgery of the eye has several advantages:
- There is no risk of infection from the laser light
- Laser surgery can be performed in an outpatient setting, without having to stay in the hospital overnight
- The surgeon has great precision and control
Which eye diseases can be treated with laser surgery?
Diseases of the Retina
Retinal tears or holes: The retina is the inner layer of the eye that senses light and helps you to see. If the retina tears, it can separate from the back wall of the eye. This is called detachment of retina, and it can cause loss of sight.
Symptoms of retinal tears include:
- Sudden flashes of light
- "Floaters" or specks in your vision
Most retinal tears can be treated with the argon or krypton laser, if they are found before the retina detaches. The laser helps bond the retina to the wall of the eye, preventing a retinal detachment. If retinal detachment has already occurred, the laser may be used as part of surgical repair of the detachment.
Diabetic Retinopathy
Eye disease from diabetes is a major cause of vision loss. Diabetes can cause blood vessels in the retina to grow abnormally. The vessels can leak fluid (macular edema) or bleed inside the eye.
Laser surgery to treat diabetic retinopathy:
Seals leaking blood vessels to reduce macular edema, helping to prevent further vision loss
Slow or stops growth of abnormal blood vessels, decreasing the chance of bleeding in the eye
Macular degeneration: The macula is the small, central area of the retina that allows us to see fine details clearly. Macular degeneration affects your central or reading vision.
Most people have "dry" macular degeneration, which cannot be helped by laser surgery.
A few people have "wet" macular degeneration. Abnormal blood vessels cause bleeding and scarring of the macula. In certain cases, these people may be treated with argon laser. The laser seals the blood vessels to prevent further damage.
There are other retina problems that can be treated with the laser, including:
- Retinal vein occlusions
- Histoplasmosis
- Central serous retinopathy
- Some tumors of the eye
After Cataract Surgery After a cataract has been removed, the capsule of the lens sometimes becomes cloudy. The neodymium-YAG laser can open up this cloudy membrane and restore clear vision. The laser is not used to remove cataracts. Glaucoma Glaucoma is disease of the optic nerve, which sends images from the eye to our brain and allows us to see. Glaucoma affects at least two out of every 100 older Americans. Glaucoma damages the optic nerve, usually because the fluid pressure inside the eye is too high. Loss of vision from glaucoma can often be prevented if your ophthalmologist discovers the disease before much damage occurs to the optic nerve. Glaucoma must be detected early if treatment is to be successful.
Eye drops or pills are the usual way to treat glaucoma. If they do not control the pressure within eye, laser surgery may be used to create tiny opening, allowing the fluid to drain and release pressure.
Refracative surgery
In procedures called photorefractive keratectomy (PRK) and laser in situkeratomileusis (LASIK), the excimer laser is used to sculpt the cornea and reduce or eliminate the need for eye-glasses or contacts lenses. |
