Understanding Glaucoma: A Guide to Protecting Your Sight

Glaucoma is a group of eye conditions that damage the optic nerve, which is vital for good vision. This damage is often caused by abnormally high pressure in your eye. It stands as a leading cause of irreversible blindness for people over the age of 60, but it can affect individuals at any age. A concerning fact is that many forms of glaucoma have no warning signs. The effect is so gradual that you may not notice a change in vision until the condition is at an advanced stage.

More than 4 million people in the U.S. live with glaucoma, yet only about half are aware they have it. This makes knowledge and proactive care essential. January is recognized as Glaucoma Awareness Month, a time dedicated to educating the public about this “silent thief of sight.” As Sierra Goetz, co-founder and senior vice president of operations at HomeCare Advocacy Network (HCAN), states, “Glaucoma is the leading cause of vision loss and blindness but, in many cases, there are no early symptoms.” This guide will help you in understanding glaucoma, its types, risk factors, and the crucial steps you can take to protect your vision.

What is Glaucoma?

At its core, glaucoma is a disease that affects the optic nerve, the critical pathway that transmits visual information from your eye to your brain. When this nerve is damaged, it can lead to blind spots in your field of vision. The most common cause of this damage is an increase in intraocular pressure (IOP), or the pressure inside your eye.

Your eye continuously produces a clear fluid called aqueous humor, which fills the front part of your eye. In a healthy eye, this fluid drains out through a mesh-like channel. If this drainage system works poorly or becomes blocked, the fluid builds up, causing the pressure inside the eye to increase. This elevated pressure can compress and damage the delicate fibers of the optic nerve, leading to permanent vision loss.

The Different Types of Glaucoma and Their Symptoms

Understanding glaucoma involves knowing its different forms, as symptoms can vary significantly depending on the type and stage of the condition.

Open-Angle Glaucoma

This is the most common form of glaucoma. It occurs when the drainage angle for fluid within the eye remains open, but the trabecular meshwork (the eye’s drainage canals) becomes less efficient over time. The pressure in the eye increases gradually.

• Symptoms: There are typically no symptoms in the early stages. Over time, patchy blind spots develop in your peripheral (side) vision. In later stages, you may experience difficulty with your central vision.

Acute Angle-Closure Glaucoma

This type is a medical emergency. It happens when the iris (the colored part of your eye) bulges forward to narrow or block the drainage angle formed by the cornea and iris. As a result, fluid can’t circulate through the eye, and pressure increases abruptly.

• Symptoms: This condition presents with sudden, severe symptoms that require immediate medical attention. These include a bad headache, severe eye pain, nausea, blurred vision, seeing halos or rings around lights, and eye redness.

Normal-Tension Glaucoma

In this form, your optic nerve becomes damaged even though your eye pressure is within the normal range. The exact cause is not fully understood, but experts believe it could be related to a sensitive optic nerve or a reduced blood supply to the nerve.

• Symptoms: Similar to open-angle glaucoma, there are no early symptoms. Vision blurs gradually, and in later stages, you may notice a loss of peripheral vision.

Pigmentary Glaucoma

This is a form of secondary open-angle glaucoma that often affects younger, nearsighted men. It occurs when pigment from the iris flakes off and clogs the eye’s drainage system, leading to increased eye pressure and optic nerve damage.

• Symptoms: Some individuals may notice halos around lights and blurred vision, particularly after exercise. A gradual loss of side vision is also a common symptom.

Who is at Risk for Glaucoma?

Because glaucoma can cause irreversible damage before you even notice symptoms, understanding the risk factors is a critical part of protecting your vision. If you fall into any of the following categories, it is especially important to have regular comprehensive eye exams.

• High Internal Eye Pressure: This is the primary risk factor for developing glaucoma.
• Age: Individuals over the age of 55 are at a higher risk.
• Heritage: People of Black, Asian, or Hispanic descent have an increased risk.
• Family History: A family history of glaucoma significantly increases your own risk.
• Medical Conditions: Certain health issues like diabetes, high blood pressure, migraines, and sickle cell anemia can contribute to your risk.
• Corneal Thickness: Corneas that are thin in the center are a known risk factor.
• Vision Correction: Being extremely nearsighted (myopic) or farsighted (hyperopic).
• Eye Injury: Previous eye trauma or certain types of eye surgery can increase your risk.
• Medication Use: Long-term use of corticosteroid medicines, especially eye drops.

The Importance of Early Detection and Treatment

Vision lost from glaucoma cannot be recovered. This fact underscores the critical importance of early detection and treatment to help protect your vision against serious damage.

As Goetz emphasizes, “There currently is no cure for glaucoma, so early detection is key.” Regular comprehensive eye exams are the best way to detect glaucoma in its early stages. Unlike a basic vision screening, a comprehensive exam includes measuring your eye pressure, checking for optic nerve damage, and testing your visual field.

If glaucoma is detected, your doctor can prescribe treatments to help lower the pressure in your eye and prevent further vision loss. Treatment options often start with prescription eye drops but may also include oral medications, laser therapy, or surgery. The goal of any treatment is to preserve the vision you still have.

Taking Control of Your Eye Health

Understanding glaucoma is the first step toward safeguarding your sight. While you can’t prevent glaucoma, you can take proactive steps to catch it early and manage it effectively.

Talk to your healthcare professionals to determine how often you should schedule comprehensive eye exams, especially if you have any of the risk factors mentioned above. For more information about glaucoma and to find valuable resources, speak with your eye doctor or visit the website of The Glaucoma Research Foundation. Don’t wait for symptoms to appear—make your eye health a priority today.