Glaucoma is one of the leading causes of blindness in the United States. It is a disease that typically affects older people, but it can occur at any age. It occurs when the pressure inside the eye rises high enough to damage the optic nerve. The eye has about 1 million tiny nerve fibers which run from the back of the eye to the brain. These nerve fibers allow us to see. As a disease, glaucoma causes the destruction of these fibers. Althought, it was once thought that the loss of these fibers was due strictly to high pressure in the eye, the medical field now knows that even patients with normal eye pressure can have glaucoma and potentially lose the nerve fibers that connect the brain and the eye.
Unfortunately, there are no symptoms of glaucoma until advanced, irreversible damage has occurred. Therefore, routine testing by an ophthalmologist or optometrist can detect glaucoma before symptoms appear. If treatments are started early enough, vision loss can be prevented. The main aim of glaucoma treatment is to lower the eye pressure, either with eye drops or surgery.
The reason that eye pressure is high in many glaucoma patients is that the drainage system in the eye is not working properly. The fluid in the eye, called aqueous humor, does not flow out of the eye as quickly as it should. The drainage system lies in a part of the eye called the angle, which is between the outer layer and the iris of the eye. This angle can be open or closed.
There are several kinds of glaucoma. The most common form of glaucoma is called chronic open angle glaucoma. The drainage angle is open in these patients, but the eye fluid does not drain as quickly as it should. Closed-angle glaucoma occurs when the drainage angle closes, and almost no eye fluid can escape. During closed-angle glaucoma, eye pressure can become very high, and there is pain. Angle closure glaucoma is a medical emergency and must be treated immediately. If sustained high pressure is allowed to continue for too long, blindness can result.
People at greatest risk for developing chronic open angle glaucoma include those who are over 40, diabetic, near-sighted, have had past eye injury, African-American, or who have a family history of glaucoma.
SLT (Selective Laser Trabeculoplasty) is an advanced laser system that improves the flow of fluid in the eye, lowering eye pressure for patients with glaucoma.
By using a combination of frequencies, the SLT laser can work at very low levels. Using a focused, narrow wavelength, SLT targets specific cells of the eye which contain melanin, leaving surrounding cells intact. The procedure is painless, has no side effects, and can be safely repeated many times if needed. SLT is an alternative for those who have been treated unsuccessfully with traditional laser surgery or with pressure lowering drops.