What is Keratoconus? Symptoms, Causes, and Diagnosis Explained by a Brisbane Specialist

If you’ve ever asked yourself, “What is keratoconus?”, you’re not alone. As an eye specialist based in Brisbane, I often meet patients who have never heard of the condition until they’re diagnosed with it—or are worried they might have it. Keratoconus is more common than people think, and catching it early can make a significant difference in managing your vision and protecting your eye health.

In this post, we’ll dive into what keratoconus actually is, its most common symptoms, what causes it, and how it’s diagnosed. Whether you’re concerned about your vision or just curious to know more, this guide will give you the answers you need—straight from a local expert.

So, What is Keratoconus?

Keratoconus is a progressive eye condition where the normally round dome-shaped cornea (the clear front surface of the eye) becomes thin and begins to bulge outward into a cone shape. This irregular shape affects how light enters the eye and focuses on the retina, leading to distorted and blurred vision.

Unlike typical vision issues that can be corrected easily with glasses, keratoconus causes more complex distortions, often leading to rapidly changing prescriptions and frustration for patients. It usually begins in the teenage years or early twenties and can worsen over time.

Keratoconus Symptoms: What to Watch Out For

Early keratoconus can be subtle and easily mistaken for regular short-sightedness or astigmatism. But as the condition progresses, the symptoms become more noticeable. Here are some of the most common keratoconus symptoms:

• Blurred or distorted vision: This is often the first sign. You might notice that straight lines look wavy or ghosted.

• Increased light sensitivity: Bright lights—especially at night—can become difficult to tolerate, causing glare or halos.

• Frequent changes in glasses or contact lens prescriptions: If your optometrist keeps updating your script every few months, keratoconus might be the reason.

• Difficulty seeing at night: Night driving becomes a challenge, with lights seeming smeared or doubled.

• Eye strain or headaches: These can result from trying to compensate for poor vision.

Some patients also report seeing multiple images with one eye (known as monocular polyopia or monocular diplopia), or feeling like their vision “wobbles” slightly during the day.

Causes of Keratoconus: What We Know

While the exact causes of keratoconus aren’t fully understood, research has pointed to several contributing factors:

• Genetics: About 10-20% of people with keratoconus have a family history of the condition.

• Eye rubbing: One of the most significant modifiable risk factors. Chronic eye rubbing, especially in people with allergies, can damage the cornea over time.  YOU MUST CONTROL EYE ALLERGIES AND STOP RUBBING YOUR EYES IF YOU HAVE KERATOCONUS.

• Underlying conditions: Conditions like eczema, hay fever, or Down syndrome are more commonly seen in people with keratoconus.

• Oxidative stress: Damage from free radicals in the eye may also weaken the corneal structure over time.

It’s important to note that keratoconus is not caused by wearing contact lenses—a common myth that still circulates.

Diagnosing Keratoconus: How It’s Detected

If you’re experiencing symptoms like blurred vision, frequent prescription changes, astigmatism, or light sensitivity, your optometrist or ophthalmologist may suspect keratoconus. But how do we confirm it?

The gold standard for diagnosing keratoconus is corneal topography—a painless, non-invasive scan that maps the surface curvature of your eye in high detail. It allows us to spot even early signs of corneal thinning and bulging, long before vision becomes noticeably impaired.

Other diagnostic tools include:

• Pachymetry: Measures the thickness of the cornea.

• Corneal biomechanics: with the Oculus Corvis device

• Corneal tomography: Provides a 3D image of the cornea, detecting even subtle structural changes.

• Refraction tests: To assess how light is being bent as it enters the eye and to detect irregular astigmatism.

Early diagnosis is essential. With newer treatments like corneal cross-linking, we can now slow or even halt the progression of keratoconus if it’s caught early.

Why It Matters

Untreated, keratoconus can lead to severe vision impairment and may eventually require a corneal transplant. But with proper diagnosis and treatment—ranging from specialised contact lenses to surgical options—most people can continue leading full, active lives.

If you’ve been wondering, “What is keratoconus?” or if you suspect your vision changes might be more than just regular aging or astigmatism, it’s worth speaking to your eye care professional.

As a Brisbane-based keratoconus specialist, I’ve helped many patients find clarity—literally and emotionally—by catching this condition early and guiding them through their treatment options.

Final Thoughts

Keratoconus may sound daunting, but knowledge is the first step to managing it. Pay attention to your vision. If you or your child is experiencing symptoms like blurred vision, astigmatism, light sensitivity, or frequent changes in prescriptions, don’t brush it off.

Book an eye exam, ask questions, and get informed.

Your sight is too important to ignore.

Need expert keratoconus help in Brisbane?

If you have concerns about keratoconus or would like a second opinion, we’re here to help. Get in touch today to book an assessment with a specialist who understands both the medical and personal side of living with keratoconus.