Types of Glaucoma
There are several different glaucoma types. The most common include open angle glaucoma, angle closure glaucoma, and congenital glaucoma. Although the severity of the disease varies depending on the type, it is necessary to seek help from an eye care professional to control and prevent the damage caused by glaucoma in any form.
Glaucoma is a group of diseases sharing certain features, commonly including high intraocular pressure (IOP), damaged optic nerves, and loss of peripheral vision.
Glaucoma types include:
- Open angle glaucoma
- Angle closure glaucoma
- Low tension glaucoma
- Normal tension glaucoma
- Congenital glaucoma
- Secondary glaucoma
- Pigmentary glaucoma
- Steroid-induced glaucoma
- Neovascular glaucoma.
Glaucoma Types Explained
The following sections explain in detail the different forms of glaucoma listed above.
Open Angle Glaucoma
Primary open angle glaucoma (also known as chronic glaucoma) mainly affects adults over age 35. This is the most common glaucoma type, affecting about 1 percent of people in the United States. In most cases, by the time open angle glaucoma is detected, it has already begun doing damage.
Angle Closure Glaucoma
Angle closure glaucoma is less common than open angle glaucoma. It also differs in that symptoms begin in a sudden, violent attack.
In angle closure glaucoma, the fluid at the front of the eye cannot reach the angle and leave the eye. The angle gets blocked by part of the iris. People with this glaucoma type have a sudden increase in eye pressure. Symptoms include severe pain and nausea, as well as redness of the eye and blurred vision.
If you have these symptoms, you need to seek treatment immediately. This is a medical emergency. If your doctor is unavailable, go to the nearest hospital or clinic.
Without treatment to improve the flow of fluid, the eye can become blind in as few as one or two days. Usually, prompt laser surgery and medicines can clear the blockage and protect sight.
It's also possible to get both open angle and angle closure glaucoma ("combined-mechanism"). Regular eye examinations can help protect against the onset of both types of glaucoma.
Other names for angle closure glaucoma include:
- Acute glaucoma
- Closed angle glaucoma
- Narrow angle glaucoma.
Low Tension or Normal Tension Glaucoma
In low tension or normal tension glaucoma, optic nerve damage and narrowed side vision (peripheral vision) occur in people with normal eye pressure. Lowering eye pressure at least 30 percent through medicines slows the disease in some people. Glaucoma may worsen in others despite low pressures.
A comprehensive medical history is important in identifying other potential risk factors, such as low blood pressure, that contribute to low tension glaucoma. If no risk factors are identified, the treatment options for this glaucoma type are the same as for open angle glaucoma.