Glaucoma is a group of eye diseases that can cause vision loss due to damage to the optic nerve, which transmits visual signals from the eye to the brain.

Your eyes regularly produce a fluid called aqueous humor, which is found between the clear outer layer and the lens of your eye. The production and drainage of this fluid regulate your eye pressure. When this fluid does not drain properly, it can build up and place extra pressure on the optic nerve, increasing the risk of glaucoma.

Glaucoma is the second leading cause of blindness in the United States. Recognizing symptoms such as partial vision loss, increased eye pressure, and headaches can be an important sign to seek help from an ophthalmologist promptly.

Types of Glaucoma

There are two main types of glaucoma:

primary glaucoma: Develops when the aqueous humor is not draining or functioning correctly, leading to increased eye pressure.

secondary glaucoma: Occurs due to external factors such as other medical conditions or eye trauma that interfere with the eye’s drainage system, increasing pressure on the optic nerve.

Each of these types has multiple subtypes. While they are similar in nature, the symptoms can vary slightly depending on the specific form.

Primary glaucoma subtypes include open-angle glaucoma, angle-closure glaucoma, normal tension glaucoma, and congenital glaucoma. Secondary glaucoma subtypes include pigmentary glaucoma, neovascular glaucoma, exfoliative glaucoma, uveitic glaucoma, and traumatic glaucoma.

Open-Angle Glaucoma Symptoms

Open-angle glaucoma is the most common type in the United States. Most individuals with this form do not notice early symptoms. As it advances, you may begin to lose peripheral (side) vision. By the time this symptom is detected, the disease may already be at a progressed stage and can lead to central vision loss or even blindness.

Vision loss from open-angle glaucoma is not reversible. However, regular eye checkups can help detect it early, and your eye doctor may suggest preventative strategies like wearing protective eyewear.

Angle-Closure Glaucoma Symptoms

Angle-closure glaucoma, also known as narrow-angle or closed-angle glaucoma, occurs when the angle between the iris and the cornea closes. This closure can cause a sudden or gradual increase in eye pressure.

Common symptoms include:

  • headache

  • eye pain

  • blurry vision

  • redness

  • nausea or vomiting

  • seeing halos or rainbows around lights

Prompt evaluation by an ophthalmologist is crucial if you experience these symptoms, as untreated angle-closure glaucoma can cause severe optic nerve damage and vision loss.

Normal Tension Glaucoma Symptoms

Normal-tension glaucoma is a type of open-angle glaucoma where eye pressure remains within a normal range. Often, early symptoms are not noticeable.

As the condition progresses, symptoms such as blind spots, blurry vision, and trouble adjusting to bright light may occur due to gradual damage to the optic nerve.

Congenital Glaucoma Symptoms

Congenital glaucoma is a rare condition present at birth, caused by improper eye development during pregnancy.

Children with this form may exhibit:

  • excessive tearing

  • cloudy cornea

  • sensitivity to light

  • enlarged eyes

Pigmentary Glaucoma Symptoms

This type occurs when pigment granules from the iris detach and block the drainage system, causing fluid buildup and increased eye pressure.

Though early symptoms may be absent, later signs can include:

  • eye pain

  • blurry vision

  • seeing halos around lights

  • redness

  • sensitivity to bright light

  • headaches intensified by reading, exercise, or blinking

Neovascular Glaucoma Symptoms

Neovascular glaucoma results from abnormal blood vessel growth in the drainage areas of the eye, often triggered by conditions such as diabetes or high blood pressure.

Common symptoms include:

  • eye pain

  • redness

  • blurry vision

  • photosensitivity (light sensitivity)

Exfoliative Glaucoma Symptoms

This condition develops when flaky, protein-like material accumulates in the eye, blocking fluid drainage and raising eye pressure. It typically progresses more quickly and to a greater degree than other types.

Although symptoms are absent in early stages, peripheral vision loss is often seen later.

Uveitic Glaucoma Symptoms

Uveitic glaucoma is caused by uveitis, an inflammatory condition that affects the eye’s middle layer. Inflammation blocks the normal fluid drainage, increasing eye pressure and risk of glaucoma.

Symptoms often include:

  • eye pain

  • redness

  • blurry vision

  • sensitivity to light

Traumatic Glaucoma Symptoms

This type of glaucoma results from eye injuries. It may occur immediately after the trauma or years later.

Symptoms may include:

  • swelling

  • eye bruising

  • severe eye pain

  • loss of vision

  • blood accumulation in the white of the eye

  • watery eyes

  • redness

Symptoms in Children

Pediatric or childhood glaucoma is rare and can be congenital or develop due to injury or underlying health conditions. It is categorized by age of onset:

  • neonatal glaucoma: At birth or within the first month

  • infantile glaucoma: Between 1 and 24 months

  • late-onset glaucoma: Between 2 and 3 years

Common symptoms across all types include:

  • cloudy cornea

  • sensitivity to light

  • excessive tearing

  • enlarged eyes

  • loss of vision

In some cases, children may also show behavioral changes like increased fussiness or picky eating habits.

When to Contact a Healthcare Provider

It’s important to see an ophthalmologist if you notice changes in your vision or experience symptoms like:

  • severe eye pain

  • vision problems

  • eye redness

  • headache

  • nausea

Your doctor will likely perform a dilated eye exam to confirm whether you have glaucoma or another eye condition, and then provide appropriate treatment based on the findings.

Questions to Ask Your Healthcare Provider

If you've been diagnosed with glaucoma or are experiencing symptoms, consider asking:

  • How can I identify the type of glaucoma I have?

  • Will my symptoms go away without treatment?

  • Can vision loss from glaucoma be reversed?

  • What lifestyle habits or assistive devices do you recommend to help protect my vision?

A Quick Review

Glaucoma is a collection of eye diseases that can lead to irreversible vision loss and even blindness if left untreated. Since many types of glaucoma show no symptoms until they are advanced, it's essential to be vigilant. Early warning signs may include eye pain, headaches, blurry vision, and light sensitivity.

If you detect any changes in your vision or suspect glaucoma, visiting an ophthalmologist promptly can help you start treatment early and protect your sight.