Early signs of glaucoma

What is Glaucoma?

Glaucoma is one of the leading causes of blindness, particularly for older adults over the age of 60. However, in the early stages, most types of glaucoma develop gradually and without any noticeable symptoms at first. Because there are often no clear warning signs, many people don't realise they have glaucoma until significant optic nerve damage has already occurred.

That's why being aware of minor changes in vision—like peripheral vision loss or blurred vision—can be key to detecting glaucoma early, when treatment is most effective at preventing irreversible vision loss.

Glaucoma often has no early symptoms

Unlike some eye conditions that have obvious symptoms right away, the most common forms of glaucoma develop slowly over many months or even years with no initial signs that would make you feel you need to seek medical attention.

At first, glaucoma causes peripheral vision loss outside of your main field of vision. But this early gradual loss of side vision usually goes undetected, since we aren't as attuned to changes in our peripheral vision.

Unfortunately, by the time glaucoma begins to affect central vision and impair your sharper, straight-ahead sight, significant damage to the optic nerve has already occurred. That's why getting routine, comprehensive eye exams is the only reliable way to catch glaucoma in its early stages, before vision loss sets in. Ophthalmologists can detect changes in the optic nerve and vision even before you notice symptoms yourself.

Common symptoms of glaucoma and when do they appear?

It's often said that glaucoma is the 'silent thief of sight.' Why? Because most people with open-angle glaucoma, the most common type of glaucoma, experience virtually no symptoms in the early stages. It's a slow progression, and by the time vision loss is noticed, the condition has usually advanced.

While the early signs of glaucoma can be elusive, there are symptoms to watch out for as the disease progresses including:

Gradual peripheral vision loss

Often, the first subtle vision sign of glaucoma is a creeping loss of peripheral or side vision. This loss usually starts in the areas closest to your nose, just outside your central field of vision. It slowly creates blind spots in your peripheral vision that most people simply don't notice at first. But if glaucoma remains undetected and untreated, the vision loss continues spreading little by little. Eventually it leads to tunnel vision, where only the central area you're looking directly at remains visible.

Halos around lights

Some people with early-stage glaucoma may begin noticing rainbow-like halos or rings appearing around bright lights, especially at night. This phenomenon is the result of pressure gradually building up inside the eye over a long period of time and starting to damage the optic nerve. The distortion makes point sources of light seem to glow with a hazy glow.

Blurry vision

In the initial stages, your vision can also start to seem generally misty or blurry before true measurable vision loss sets in. This overall blurriness and decline in sharpness are due to very subtle changes and damage beginning to occur to individual fibres in the optic nerve. The fuzziness tends to come on slowly and worsen gradually as glaucoma progresses.

Awareness is the first step to proactive care. Being informed about glaucoma, its silent nature, and the symptoms that may arise gives you the power to advocate for your eye health before it's too late.

Symptoms in acute glaucoma

While most types of glaucoma develop slowly without early symptoms, one form of glaucoma called acute angle-closure glaucoma can cause noticeable vision problems. Symptoms of acute angle-closure glaucoma come on suddenly and include severe eye pain, nausea, and blurred vision.

The eyes become extremely red, and you may see rainbow-colored halos around lights. This sudden form of glaucoma is an ophthalmologic emergency. It requires immediate treatment to prevent permanent vision loss and blindness. If you experience these acute glaucoma symptoms, seek medical attention right away.

Who is at higher risk?

There are certain risk factors that make some groups of people more likely to develop glaucoma:

• Aged over 60 - As with many conditions, age is a factor. Those over 60 are at an increased risk, though for certain ethnicities, the risk can appear even earlier
• Family history of glaucoma - Genetics play a role. If someone in your family has glaucoma, you're at a heightened risk
• Farsightedness or near-sightedness
• Previous injuries or health conditions like diabetes, high blood pressure, and migraine headaches - Past trauma to the eye or certain medical conditions can escalate the risk

People with risk factors like these should be extra vigilant about any vision changes and get their eyes examined routinely to screen for glaucoma. Catching it early is key to preserving sight.

Is it glaucoma or something else?

It's not uncommon for eye symptoms to overlap among various conditions, and glaucoma is no exception. Blurred vision, for instance, could be a result of cataracts, while eye pain could stem from infections or other inflammations.

Diabetic retinopathy, another eye ailment, might even mimic the vision loss associated with glaucoma. Therefore, while it's essential to be vigilant about changes in your vision, it's equally crucial to get a definitive diagnosis from an eye care specialist.

Importance of regular eye exams

Because the most common forms of glaucoma have no warning signs in the early stages, comprehensive eye exams play a critical role in early detection. Eye doctors can perform exams of the optic nerve and visual field tests to check for early glaucoma damage, often before you notice any vision changes yourself.

Catching glaucoma in its early stages through routine exams gives treatment the best chance of successfully preserving vision and preventing irreversible blindness.

Other useful tips for detecting glaucoma

Besides getting regular and comprehensive eye exams, there are a few other things you can do to help screen for possible glaucoma:

• Pay attention to changes in your overall vision or eye comfort. If your eyes seem more strained or activities like reading become harder, it could indicate a problem
• Have your eyes dilated during exams. The dilating drops allow the doctor to get a better view of the optic nerve to check for damage
• Know your family history. If close relatives have had glaucoma, be extra vigilant about symptoms and get screened more frequently
• Don't delay. If you notice potential glaucoma symptoms like blurriness or halos, visit your eye doctor promptly. Waiting allows more permanent damage
• Consider advanced technologies. Diagnostic methods like optical coherence tomography (OCT) scans that can provide enhanced early detection of optic nerve changes
• Be proactive. Acting fast allows the best chance of preserving vision and protecting yourself from blindness.