Ask the Doc: What’s the Difference Between Open-angle and Closed-angle Glaucoma?

Featured this month: Dr. Evan Lagouros, Fellowship-Trained Glaucoma Specialist

“Glaucoma can be divided into open-angle and closed-angle glaucoma. Open-angle glaucoma (OAG) is caused by poor outflow of the drainage canals in your eye, resulting in increased pressure. OAG, the most common form of glaucoma, has no symptoms, develops over a number of years, and can cause gradual and permanent vision loss.

Closed-angle glaucoma (CAG), the less common form of the two in the US, is caused by a mechanical obstruction in the drainage system inside of the eye, resulting in a sudden rise in pressure. This type of glaucoma can develop very quickly and is then referred to as acute narrow angle glaucoma. With this type of glaucoma there are noticeable symptoms of acute eye pain, nausea, decreased or blurry vision, headache, and/or eye redness. It can result in rapid damage to the eye from very high eye pressure and requires emergency medical attention in order to preserve sight in the eye.

Gradual onset CAG is caused when the angle between the cornea and iris becomes too narrow or closed, allowing pressure to build high enough to cause damage to the optic nerve before fluid can escape. CAG is common in farsighted eyes because of the physical structure of the eye.

Most people who have glaucoma don’t realize that they have it early in the disease course. Increased pressure is commonly associated with glaucoma; however, you can’t feel the pressure in your eye unless there’s a sudden and dramatic increase, and eye pressure alone is not sufficient to diagnose or treat glaucoma. Routine eye exams are the key to detecting the disease early enough to treat your condition and prevent progression of disease and loss of vision.

People at higher risk of developing open-angle glaucoma are over the age of 60, are of African American or Hispanic descent and have family members with the disease. Early detection could help you keep your eyesight – schedule your complete eye exam today by calling Illinois Eye Center at (309) 243-2400. You can also visit our website for more information on glaucoma and additional treatment options.” – Dr. Evan Lagouros

Holiday Hours

Saturday, 9/2

Peoria office open by appointment only

(Pekin & Washington are always closed on Saturdays)

Monday, 9/4

All offices closed

Tuesday, 9/5

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Note: The Washington office will remain closed for renovations until Monday, Sept 18. 2023