The three most common types of glaucoma are open-angle, and narrow-angle, and angle-closure, which are the same condition at different stages. All of them:

• cause damage to the optic nerve because of high inner eye pressure
• may be found through glaucoma testing during an eye exam
• may require medical treatment from a glaucoma specialist
• can be treated and managed with medicines and surgery

Open-Angle Glaucoma

The name open-angle glaucoma means it is not from any problem with the normal angle between the cornea and iris in your eye. Ninety percent or more of people who have glaucoma have the open-angle type.

Open-angle glaucoma is dangerous because inner eye pressure rises slowly and damages your optic nerve. You can have open-angle glaucoma and glaucoma vision loss without knowing it.

Open-angle glaucoma starts by taking away how well you see objects off to your sides. As it gets worse, you see more of a shadow or blackness around the edges of your vision. If you don’t get treatment, symptoms become more like those from angle-closure glaucoma.

Angle-Closure Glaucoma

When the angle between your cornea and iris is normal, fluids drain from your eyes normally and eye pressure stays about the same. If the angle becomes too narrow, it can cover up the fluid-drainage canals (narrow angle) or close them off (angle closure). Inner eye pressure then rises quickly and causes acute glaucoma that requires treatment right away.

Symptoms of narrow-angle and angle-closure glaucoma may include eye redness, eye pain, headaches, blurry vision, halo images around lights, upset stomach, and more loss of peripheral vision. It’s possible to have any or all of these symptoms. If you do, see an eye doctor (ophthalmologist) right away for glaucoma screening.

By examining your eyes and their optic nerves, measuring your inner eye pressure, and checking your field of vision, an ophthalmologist can tell which kind of glaucoma you may have.

In next week’s blog, we talk about all the different kinds of glaucoma screening.

The goal of this series of weekly blogs is to help you feel informed and confident, wherever you are in learning about glaucoma.

Visit sceyes.org/blog weekly to learn more.

Please provide feedback, suggested topics, or questions about glaucoma in the Contact Us section below. Thank you.