January is Glaucoma Awareness Month, but just how much do you know about Glaucoma? Most of us have at least heard the word and most of us associate glaucoma with the elderly. But, did you know that you don’t have to be ‘old’ to develop this non-reversible eye disease?
Glaucoma is a condition that is often associated with a buildup of pressure inside the eye. This usually happens when eye fluid doesn’t circulate as it normally should in the front part of the eye. The increased pressure, called intraocular pressure, can damage the optic nerve, which transmits images to the brain. If damage to the optic nerve from high eye pressure continues, glaucoma will cause permanent loss of vision. Without treatment, glaucoma can cause total permanent blindness within a few years.
There are various forms of glaucoma:
Open-angle glaucoma is the most common type of glaucoma. The structures of the eye appear normal, but fluid in the eye does not flow properly through the drain of the eye, called the trabecular meshwork.
Angle-closure glaucoma is also called acute or chronic angle-closure or narrow-angle glaucoma. This type of glaucoma is less common in the United States. Poor drainage is caused because the angle between the iris and the cornea is too narrow and is physically blocked by the iris. the fluid at the front of the eye cannot drain through the angle and leave the eye. 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 restore the flow of fluid, the eye can become blind. Usually, prompt laser surgery and medicines can clear the blockage, lower eye pressure, and protect vision.
In low-tension or normal-tension glaucoma, optic nerve damage and narrowed side 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 to identify 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 low-tension glaucoma are the same as for open-angle glaucoma.
In congenital glaucoma, children are born with a defect in the angle of the eye that slows the normal drainage of fluid. These children usually have obvious symptoms, such as cloudy eyes, sensitivity to light, and excessive tearing. Conventional surgery typically is the suggested treatment, because medicines are not effective and can cause more serious side effects in infants and be difficult to administer. Surgery is safe and effective. If surgery is done promptly, these children usually have an excellent chance of having good vision.
Secondary glaucomas can develop as complications of other medical conditions. For example, a severe form of glaucoma is called neovascular glaucoma, and can be a result from poorly controlled diabetes or high blood pressure. Other types of glaucoma sometimes occur with cataract, certain eye tumors, or when the eye is inflamed or irritated by a condition called uveitis. Sometimes glaucoma develops after other eye surgeries or serious eye injuries. Steroid drugs used to treat eye inflammations and other diseases can trigger glaucoma in some people. There are two eye conditions known to cause secondary forms of glaucoma.
Pigmentary glaucoma occurs when pigment from the iris sheds off and blocks the meshwork, slowing fluid drainage.
Pseudoexfoliation glaucoma occurs when extra material is produced and shed off internal eye structures and blocks the meshwork, again slowing fluid drainage.
Depending on the cause of these secondary glaucomas, treatment includes medicines, laser surgery, or conventional or other glaucoma surgery.
Glaucoma is usually inherited and may not show up until later in life, but there are cases of infants and children who have glaucoma. In African-Americans, glaucoma occurs more frequently and at an earlier age and with greater loss of vision.
You are at an increased risk of glaucoma if you:
- Are of African-American, Irish, Russian, Japanese, Hispanic, Inuit, or Scandinavian descent
- Are over age 40
- Have a family history of glaucoma
- Have poor vision
- Have diabetes
- Have high blood pressure
- Take certain steroid medications, such as prednisone
- Have had trauma to the eye or eyes
For most people, there are usually few or no symptoms of glaucoma. The first sign of glaucoma is often the loss of peripheral or side vision, which can go unnoticed until late in the disease. This is why glaucoma is often called the “sneak thief of vision.”
Detecting glaucoma early is one reason you should have a complete exam with an eye doctor every one to two years so it can be diagnosed and treated before long-term vision loss occurs. Occasionally, intraocular pressure can rise to severe levels. In these cases, sudden eye pain, headache, blurred vision, or the appearance of halos around lights may occur.
If you have any of the following symptoms, seek immediate medical care:
- Seeing halos around lights
- Vision loss
- Redness in the eye
- Eye that looks hazy (particularly in infants)
- Nausea or vomiting
- Pain in the eye
- Narrowing of vision (tunnel vision)
While glaucoma cannot be prevented, it can be treated. Treatments include:
Eye drops for glaucoma. These either reduce the formation of fluid in the front of the eye or increase its outflow. Side effects of glaucoma drops may include allergy, redness of the eyes, brief stinging, blurred vision, and irritated eyes. Some glaucoma drugs may affect the heart and lungs. Be sure to tell your doctor about any other medications you are currently taking or are allergic to. Because glaucoma often has no symptoms, people may be tempted to stop taking, or may forget to take, their medicine. You need to use the drops as long as they help control your eye pressure as directed by your doctor. Regular use is very important to managing pressures.
Laser surgery for glaucoma. Laser surgery for glaucoma slightly increases the outflow of the fluid from the eye in open-angle glaucoma or eliminates fluid blockage in angle-closure glaucoma. Types of laser surgery for glaucoma include trabeculoplasty, in which a laser is used to pull open the trabecular meshwork drainage area; iridotomy, in which a tiny hole is made in the iris, allowing the fluid to flow more freely; and cyclophotocoagulation, in which a laser beam treats areas of the middle layer of the eye, reducing the production of fluid.
Microsurgery for glaucoma. In an operation called a trabeculectomy, a new channel is created to drain the fluid, thereby reducing intraocular pressure that causes glaucoma. Sometimes this form of glaucoma surgery fails and must be redone. For some patients, a glaucoma implant is the best option. Other complications of microsurgery for glaucoma include some temporary or permanent loss of vision, as well as bleeding or infection.
As part of your healthy new year, make an appointment today to see your eye care professional.
Sources: WebMD and the National Eye Institute