What is Glaucoma?
Glaucoma is a group of diseases characterized by optic nerve injury with resultant visual loss. While many individuals with glaucoma have an elevated eye pressure, it is a risk factor for glaucoma and not a part of the disease definition. Most individuals with mildly elevated eye pressure will not develop glaucoma and many individuals with glaucoma have never had a documented elevated pressure. Glaucoma is prevalent in all populations and can lead to blindness, if not diagnosed and treated in a timely manner. Glaucoma is more common in older individuals and in certain ethnic groups. Moreover, a positive family history of glaucoma is a significant risk factor for the disease. The latter facts have led many investigators to propose that at least a subset of glaucoma may have a genetic basis.
How does glaucoma affect vision?
Glaucoma is a disease of the optic nerve, the main pathway that carries signals from the eye to the brain. In glaucoma the optic nerve fibers gradually die, resulting in a slow loss of peripheral (side) vision and ultimately all vision.
What are the symptoms of glaucoma?
One of the diagnostic problems with glaucoma is that there are very few symptoms early in the course of the disease. Eyes with glaucoma gradually lose side vision. This side vision loss can result in tunnel vision - vision like one is looking through a tube. This can result in the individual tripping over objects or failing to notice objects approaching from the side.
Individuals with glaucoma may not notice early vision loss because the peripheral vision from the fellow eye can cover for the loss. Additionally, elderly people may attribute any vision loss to cataract. Because early glaucoma has so few symptoms it has been estimated that one-half of all individuals with glaucoma are unaware that they have the disease. This is why a thorough eye examination, including examination of the optic nerve - and not just measurement of eye pressure - is critical.
What causes glaucoma?
Glaucoma is caused by the death of optic nerve fibers. The cause of this death is not fully understood and is an area of intense research. It is known that there are people in whom this damage is more likely to occur. There are four major risk factors for the development of primary open angle glaucoma, the most common form of glaucoma. These risk factors are: advanced age, African-American heritage, a family history of glaucoma, and high pressure within the eye.
Is there a genetic test for Glaucoma?
Yes. The John and Marcia Carver Nonprofit Genetic Testing Laboratory has available a clinical nonprofit test for Juvenile open angle glaucoma as well as Primary Open Angle Glaucoma. See Genetic Tests We Offer
Is there a treatment for Glaucoma?
Glaucoma is a disease of the optic nerve. Logic would suggest that we should treat the optic nerve directly to protect it or regenerate it. Unfortunately, the optic nerve, like the spinal cord, is an extension of the brain and is not capable of repair. Therefore our treatments are focused on treating the one risk factor for glaucoma that can be altered: the eye pressure. For most individuals with glaucoma, simply using eye drops can lower the pressure within the eye. If these drops are inadequate there are laser and microsurgical procedures that can be performed to lower the pressure. The good news about glaucoma is that it is a very treatable disease. If glaucoma is diagnosed early and treated appropriately severe vision loss is unlikely.
Is there a clinical trial available for this particular condition?
Research regarding the eye and blinding eye diseases is ongoing and the answer to this question might change on any given day. Thankfully there are resources available today to assist anyone interested in monitoring progress.
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Additional Resources:
Where can I learn more about glaucoma?
GeneTests is a publicly funded web site that provides medical genetics information. While primarily targeted to physicians, researchers and other healthcare providers, patients and their families interested in a reliable resource for their own research will find this up-to-date comprehensive web site an invaluable tool. See as found on GeneTests.org
If you have any specific questions about Glaucoma, please consult your personal physician.
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