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Primary open-angle glaucoma is a progressive eye disease caused by increased intraocular eye pressure (IOP). It leads to optic nerve (connection pathway between the eye and brain) damage and vision loss. If left untreated, open-angle glaucoma results in blindness.
Glaucoma is an umbrella term for eye conditions caused by increased eye pressure. The eye is filled with aqueous humor (clear fluid) that is responsible for eye shape and providing the rest of the eye with nutrients and oxygen.
Eye fluid continuously flows, draining through a small space between the iris (colored part of the eye) and sclera (white of the eye) called the drainage angle. When the drainage angle is blocked or clogged, it leads to increased IOP. This causes damage to the optic nerve, leading to glaucoma.
Open-angle glaucoma is the most common type of glaucoma. It affects 3 million Americans and is the second leading cause of blindness worldwide.1
Glaucoma results from the drainage angle becoming blocked or clogged. This slows down the flow of eye fluid and increases eye pressure.
With primary open-angle glaucoma, the trabecular meshwork (spongy tissue in the drainage angle) slowly becomes clogged. This results in a backup of eye fluid, causing eye pressure to increase.
Closed-angle glaucoma, also called angle-closure glaucoma, is a sudden spike in intraocular pressure caused by the iris blocking the drainage angle.
Symptoms of closed-angle glaucoma include:
Closed-angle glaucoma is a medical emergency that requires immediate treatment before it causes irreversible blindness.
A variety of eye conditions that increase intraocular pressure can cause glaucoma.
Other types of glaucoma include:
Open-angle glaucoma progresses slowly over time. It is usually asymptomatic until its advanced stages, when the optic nerve is damaged.
It is called the “silent thief of sight” because many people don’t know they have increased eye pressure until their peripheral vision (side vision) changes.
Late-stage symptoms of open-angle glaucoma include:
Open-angle glaucoma is caused by increased intraocular pressure. This results in optic nerve damage, which causes vision loss.
The drainage angle stays open, but the trabecular meshwork becomes clogged. This slows down the flow of eye fluid and increases eye pressure.
While anyone can develop glaucoma, certain people have increased risk factors, including:
There is no cure for glaucoma, and optic nerve damage is permanent. However, there are steps you can take to detect glaucoma early and manage eye health, including:
Visit an eye doctor right away If you experience vision changes or other symptoms of glaucoma, including:
Routine eye exams are essential if you are at high risk of developing glaucoma.
A licensed ophthalmologist can diagnose open-angle glaucoma during a comprehensive eye exam. During the exam, the eye doctor will measure intraocular pressure using a tonometry test or a “eye puff” test.
They will use special eye drops to dilate your eyes to examine the retina (layer in the back of the eye that sends light messages to the brain), optic nerve, and other eye structures for signs of disease.
Other eye tests that can help diagnose or monitor glaucoma include:
The first goal of treating open-angle glaucoma is reducing intraocular pressure to minimize optic nerve damage. Treatment options include medication, laser therapy, and surgery.
Medicated eye drops can control eye pressure. You will most likely need to administer daily eye drops for the rest of your life. In some cases, laser or surgery can reduce the need for drops.
Prescribed eye drops for glaucoma include:
If medication alone does not lower eye pressure, laser surgery can repair the drainage angle and restore the continuous flow of eye fluid.
Trabeculoplasty is laser surgery that treats open-angle glaucoma. It unclogs the drainage angle, allowing eye fluid to flow continuously, and decreasing eye pressure.
Traditional glaucoma surgery is used when medication is ineffective in reducing intraocular pressure. Glaucoma surgery aims to repair the drainage system and unclog the trabecular meshwork.
Types of glaucoma surgery used to treat open-angle glaucoma include:
While glaucoma is irreversible, it can be treated to slow disease progression and minimize vision loss.
Catching open-angle glaucoma in its early stages is the best way to preserve vision and reduce complications, including blindness.
Getting a routine comprehensive eye exam is the best way to diagnose glaucoma early.
Open-angle glaucoma is the most common type of glaucoma. A clog in the drainage angle causes it, which disrupts the flow of eye fluid and results in an increase in eye pressure and optic nerve damage.
Open-angle glaucoma is a slow-progressing disease that doesn’t produce symptoms until advanced stages. This makes catching it early difficult. Warning signs of glaucoma include blurry vision and blind spots in peripheral (side) vision.
While it can’t be cured, open-angle glaucoma can be treated and managed with medication, laser therapy, and glaucoma surgery.
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