Glaucoma

Allen D. Beck, MD
Anastasios Costarides, MD, PhD
Annette Giangiacomo, MD
Jeremy Jones, MD

Overview

Approximately three million Americans have been diagnosed with glaucoma and another two million do not know they have it. In Georgia, the prediction is that 62,000 persons over the age of 40 will develop glaucoma. When caught and treated early, the disease can be managed for the remainder of one's lifetime.

Because most people with glaucoma have no early symptoms or pain, it is important to see an eye doctor regularly. Early diagnosis and intervention can prevent loss of vision. For this reason, annual eye exams are advised. For those with a family history of the disease and those who are over the age of 45, annual check-ups are even more important.

According to the National Eye Institute (NEI), glaucoma is a group of diseases that can damage the eye's optic nerve and result in vision loss and blindness. The damage occurs when the normal fluid pressure inside the eyes slowly rises. Increased intraocular (inside the eye) pressure damages the optic nerve, which is responsible for transmitting images to the brain. If the elevated eye pressure continues, glaucoma will worsen one’s vision. Without treatment, it can cause blindness within a few years.

 The American Academy of Ophthalmology recommends eye examinations at least every one to two years for:

• African Americans and Latinos over age 40
• Anyone over age 65
• People with a family history of glaucoma
• Individuals who have experienced a serious eye injury
• People with diabetes (yearly exams are recommended)

Childhood Glaucoma

Many people are unaware that babies and children can develop glaucoma. While relatively rare, it is a leading cause of blindness in children especially in the developing world. While far less common than other childhood conditions, such as asthma or diabetes, it is a more complex chronic condition than the more common form of glaucoma that occurs in adults. It often requires multiple procedures and examinations, and careful lifelong follow-up is essential. With early detection and prompt effective treatment, these children can maximize their potential and sometimes achieve near normal vision in at least in one eye.

Glaucoma Symptoms

At first, there are no symptoms. Vision stays normal, and there is no pain. However, as the disease progresses, a person with glaucoma may notice his or her side vision gradually failing. That is, objects in front may still be seen clearly, but objects to the side may be missed. According to the National Eye Institute, within the three million Americans who have glaucoma, only half of them are aware they have the potentially blinding disease because they have no symptoms. As the disease progresses, any of the following symptoms may appear:

• Loss of peripheral vision
• Difficulty focusing on objects
• Presence of haloes around lights
• Blurred vision

As glaucoma remains untreated, people may miss objects to the side and out of the corner of their eye. Without treatment, people with glaucoma will slowly lose their peripheral (side) vision. It is as if they were looking through a tunnel. Over time, straight-ahead vision may decrease until no vision remains.

Diagnosis

Glaucoma tests are painless and take very little time. A dilated eye exam is used to assess the patient’s vision and optic nerve; a procedure called tonometry measures eye pressure and visual field testing may be included to check peripheral vision.

Treatment

Patients need to talk with their ophthalmologist to determine which treatment option is best for their particular case. Treatment modalities may include prescription eye drops, laser or microsurgery. Traditionally in the U.S., medications are used first, but there is increasing evidence that some people with glaucoma may respond better with early laser surgery or microsurgery.

Eye drops either reduce the formation of fluid in the front of the eye or increase its outflow. There may be side effects to the drops, so patients need to completely discuss other medical conditions or prescriptions with the ophthalmologist.

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 ciliary body, reducing the production of fluid.

In microsurgery, new channel is created to drain the fluid thereby reducing intraocular pressure. Sometimes this form of glaucoma surgery fails and must be redone. Other complication of microsurgery for glaucoma include some temporary or permanent loss of vision, as well as bleeding or infection.

Research

In the spring of 2013, Emory Eye Center joined 15 other eye centers to participate in the Childhood Glaucoma Research Network's (CGRN) newly launched International Pilot Survey of Childhood Glaucoma (IPSOCG), its first collaborative international clinical research project.