What is Glaucoma:
Damage to the optic nerve with associated visual field loss.
http://www.nlm.nih.gov/medlineplus/glaucoma.html#cat45 (National Institutes of Health)
Are You at Risk For Glaucoma?
Everyone is at risk for glaucoma. However, certain groups are at higher risk than others.
People at high risk for glaucoma should get a complete eye exam, including eye dilation, every one or two years with their family optometrist.
Glaucoma is the leading cause of blindness among African-Americans. It is six to eight times more common in African-Americans than in Caucasians.
People Over 60
Glaucoma is much more common among older people. You are six times more likely to get glaucoma if you are over 60 years old.
Family Members with Glaucoma
The most common type of glaucoma, primary open angle glaucoma, is hereditary. If members of your immediate family have glaucoma, you are at a much higher risk than the rest of the population.
Family history increases risk of glaucoma four to nine times.
Hispanics in Older Age Groups
Recent studies indicate that the risk for Hispanic populations is greater than those of predominantly European ancestry, and that the risk increases among Hispanics over age 60.
People of Asian descent appear to be at some risk for angle closure glaucoma. Angle closure glaucoma accounts for less than 10% of all diagnosed cases of glaucoma. Otherwise there is no known increased risk in Asian populations.
Injury to the eye may cause secondary open angle glaucoma. This type of glaucoma can occur immediately after the injury or years later. There are reported cases with a causal relationship 20+ years later.
The most common cause is sports-related injuries.
Other Possible Risk Factors
- High myopia (nearsightedness)
- Central corneal thickness less than .5 mm.
- Types of Glaucoma
There are many types of glaucoma with the most common ones being Open Angle Glaucoma, Angle closure Glaucoma, Pigmentary Glaucoma, Pseudoexfoliation Glaucoma, and Normal Tension Glaucoma.
Primary Open Angle Glaucoma
Open Angle Glaucoma occurs when the pressure in the eye is elevated with a normal, open appearing drain area. The current thinking is that the drain becomes obstructed at a deeper level that can be observed in a living eye. This obstructed drain causes increased intraocular pressure. The pressure then causes damage to the optic nerve resulting in loss of peripheral vision followed by loss of central vision.
Angle Closure Glaucoma
Angle Closure Glaucoma occurs when the drain in the eye physically closes causing an acute rise in the intraocular pressure. This is the only form of glaucoma that can have acute symptoms. The vision can blur, the eye can get red, and there can be considerable pain. This is considered a true eye emergency and medications would be instilled immediately followed by a special LASER treatment to re-open the drain area. Otherwise the pressure could cause damage to the optic nerve resulting in loss of peripheral vision followed by loss of central vision
Pigmentary Glaucoma occurs when the anatomical position of the iris causes it to rub on the supporting ligaments of the lens. This causes pigment to be released that floats to the drain and clogs it causing the intraocular pressure to elevate. The pressure then causes damage to the optic nerve resulting in loss of peripheral vision followed by loss of central vision.
Pseudoexfoliation Glaucoma occurs when a dandruff-like substance is produced in the eye. This pseudoexfoliative material flakes off and floats to the drain and clogs it. This causes an increase in the intraocular pressure which leads to damage to the optic nerve resulting in loss of peripheral vision followed by loss of central vision.
Normal Tension Glaucoma
Normal Tension Glaucoma occurs when the pressure in the eye is never found to be elevated with a normal, open appearing drain area. The current thinking is that the pressure in the eye is too high for that particular eye (although within what is currently thought to be normal). Another theory under research is that due to the anatomy of the fine blood vessels feeding the optic nerve, it is theorized that there is a blood flow restriction during times of low blood pressure or vaso-spasm. The optic nerve acquires damage resulting in loss of peripheral vision and of central vision. This type of glaucoma requires a more extensive evaluation.
Treatments for the Glaucomas
Fortunately, there are multiple treatments for glaucoma. The typical first line of treatment is to lower the eye pressure using topical eye drops. These are very effective and work well in approximately 93% of patients. These drops can have side effects, so make sure to ask your doctor about your particular medications as well as instructions on instilling the drops.
The typical second line of treatment is LASER Trabeculoplasty. In this in-office procedure, a LASER beam is directed at the drain area of the eye (trabecular meshwork). Dr Baldinger, at Capital Eye Consultants, uses Selective Laser Trabeculoplasty (SLT), a newer and gentler type of laser to treat the trabecular meshwork (http://www.ophthalmic.lumenis.com/slt ) SLT uses shorter less intense amounts of energy to treat the drainage apparatus in the eye. Consequently, there is less “collateral damage”. The procedure takes about 10 minutes . After the procedure is completed, the patient will have several intraocular pressure measurements made over the next 45 minutes. No drops are added after the treatment and the patient will continue to maintain any glaucoma drops that may be on already. It will take 4-6 weeks after the SLT was performed to know how well they have responded to the laser treatment. Patients can be retreated if the effect of laser fades over time This procedure is effective in approximately 70% of patients and is found to be more effective in certain types of glaucoma. Some people with blue eyes will get no effect from this procedure. Fortunately, it has a very low complication and side effect rate of less than 1%. This procedure’s effect can last for up to 5 years .
The third line of treatment is the iStent. The iStent, FDA approved in 2012 is also being used by Dr. Baldinger to obtain better pressure control in his patients with open angle glaucoma. Performed at the time of cataract surgery, the iStent is the smallest medical device ever approved by the FDA . It is so small, the patient wont be able to see or feel it after surgery but it will be continuously working to help reduce eye pressure.
The iStent creates a permanent opening in the trabecular meshwork (where intraocular fluid has resistance to outflow). The placement of this tiny medical device at the time of cataract removal takes only a matter of 3 to 5 minutes. Dr. Baldinger has extensive experience with this valuable device. More information on the iStent is available here: http://www.glaukos.com/istent
Glaucoma: Risk Factors