Definition

Glaucoma describes a group of eye diseases that cause damage to the optic nerve. This degenerative eye disease is one of the leading causes of chronic blindness in the United States. Open-angle glaucoma is the most common form of glaucoma.

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Causes

Open-angle glaucoma is caused by increased intraocular pressure. Within the eye, fluid is made and then drained from the eye. If either the fluid is made too quickly (not common) or drains too slowly, then the pressure of the eye can increase, leading to damage to the optic nerve.

This damage to the optic nerve can lead to a decrease in peripheral vision and may eventually cause blindness.

Risk Factors

The risk of glaucoma increases with age. Glaucoma is more common in African American and Hispanic people. Other factors that may increase your chance of getting glaucoma include:

• Family history of glaucoma
• Glaucoma in one eye—This increases the risk of developing glaucoma in the other eye.
• Increased intraocular pressure
• Diabetes
• High blood pressure
• Migraine
• Injury to the eye
• Certain eye abnormalities such as congenital defects
• Hypothyroidism

Symptoms

Many patients with open-angle glaucoma experience few or no symptoms until the disease has progressed to the very late stages. Visual symptoms may include:

• reduced close up vision
• Loss of peripheral vision (tunnel vision)
• Difficulty driving at night
• Blindness
• Rainbows or halos

Symptoms of more severe disease may include:

• Red eyes
• Headache
• Nausea or vomiting

Diagnosis

You will be asked about your symptoms and medical history. A physical exam will be done.

Tests may include:

• Eye exam with pupil dilation
• Tonometry—a test to determine intraocular pressure
• Visual field test to determine vision loss
• Slit lamp examination—the use of a low-power microscope combined with a high-intensity light source, allows a narrow beam that can be focused to examine the front of the eye
• Photographs of the optic nerve
• Gonioscopy—to examine the outflow channels of the angle
• Analysis of the nerve fiber layer around the optic nerve

Treatment

The goal of treatment is to reduce intraocular pressure. Talk with your doctor about the best treatment plan for you. Options include:

Open-angle glaucoma can often be controlled well with proper treatment, and most patients who receive treatment will maintain their vision. Treatment options include:

• Medications in eye drop or pill form to reduce the amount of fluid the eye produces or increase the flow of fluid
• Laser treatment to increase the flow of fluid; may be used with medications
• Surgery to open a new outflow channel from the eye
• Minimally invasive glaucoma surgery (MIGS) opens outflow channels by using stents, bypasses, or implants.

Prevention

Open-angle glaucoma cannot be prevented. However, it is important to get regular eye exams to screen for glaucoma and other conditions that can affect your vision. Talk to your doctor about how often your eyes should be examined.