Glaucoma is a group of diseases than can damage the eyes optic nerve and result in vision loss and blindness. However, with early treatment, you can often protect your eyes against serious vision loss.
What is the optic nerve?
The optic nerve is the cable that takes information from the eye to the brain for interpretation. It is comprised of 1.2 million nerve fibers from the retina (film of the eye) compressed together to form a cross-sectional wire 1.5 mm in diameter.
How does open—angle glaucoma damage the optic nerve?
In the front of the eye is a space called the anterior chamber. A clear fluid flows continuously in and out of the chamber and nourishes the surrounding tissues. In the normal functioning eye the fluid leaving the chamber through the angle between the cornea and the iris, squeezing between a sieve-like tissue called the trabecular meshwork.
Sometimes fluid movement is blocked as it attempts to traverse the meshwork, and as the fluid builds up pressure in the eye elevates potentially damaging the optic nerve. This, in effect, is the basis of glaucoma and the reason controlling pressure is so important.
Does elevated eye pressure mean Glaucoma?
Not necessarily. High pressure in the eye increases the risk of damage to the optic nerve, but everyone eye is different and some eyes are more susceptible than others. If you have elevated intraocular pressure close follow-up is recommended.
Can glaucoma develop without elevated eye pressure?
Just as high pressure does not always lead to glaucoma, low pressure is not always protective. Glaucoma can develop without the elevated pressure. Although, it is not as common as open-angle glaucoma, Normal tension or even low-tension glaucoma does occur.
Who is at risk for glaucoma?
Anyone can be afflicted with glaucoma. There are certain risk factors to be considered:
- Increasing age
- Family History of glaucoma
- African Americans over age 40
- Elevated Eye Pressure
- Thin Cornea
Certain combinations of risk-factors are more concerning than others, and treatment is sometimes recommended to decrease the likelihood of progression to glaucomatous damage.
What are the symptoms of glaucoma?
Initially, there are no symptoms. Frequently referred to as the “silent thief”, glaucoma can go unnoticed until it is too late.
Should glaucoma remain untreated, peripheral vision (side vision) is first to go. Over time, a constriction of vision occurs leaving merely a central island.
How is glaucoma detected?
A thorough eye exam including:
- Visual acuity- measures quality of vision at different distances
- Visual field- a test of peripheral vision
- Dilated eye exam- drops are place in the eyes to widen the pupil for a magnified evaluation of the optic nerve and adjacent tissue.
- Tonometry- an accurate approximation of the pressure inside the eye.
- Pachymetry- a measure of the thickness of the cornea, which has been determined to be a independent risk factor of the development of glaucoma.
Can glaucoma be cured?
No. To date, there is no cure for glaucoma. Therefore emphasis on early detection and prevention are the cornerstones of glaucoma care.
How is glaucoma treated?
Whether through the use of medication, minimally invasive laser treatment, or surgery the basis of glaucoma care lies in the reduction of intraocular pressure.
Eye drops are the most common early treatment for glaucoma. Some medicines decrease the production of fluid or increase the rate of drainage within the eye. Eye drops, like every medication, have potential side effect. Therefore it is important to inform your eye doctor of any adverse reaction after beginning a treatment. As is the case with pre-existing allergies, please inform you doctor before beginning new medications.