What Is Keratoconus? An Expert Guide for Patients

Keratoconus. It’s not the easiest word to pronounce, let alone understand. But if you or someone you know has recently been diagnosed with it — or you suspect something unusual is happening with your vision — you’re not alone. In fact, keratoconus affects around 1 in every 375 people globally, and awareness is growing.

In this guide, we’ll break down exactly what keratoconus is, how it affects the eye, why it happens, and what to expect. Whether you’re newly diagnosed or just curious, this is your go-to starting point.

Understanding the Cornea and What Happens in Keratoconus

The cornea is the clear, dome-shaped front surface of your eye. It’s responsible for bending (refracting) light so it can focus on the retina, which is essential for sharp, clear vision. Think of it like the lens of a camera — it needs to be smooth and evenly curved.

In keratoconus, the structure of the cornea becomes progressively weaker. Instead of holding its round shape, the cornea thins and bulges outward into a cone-like shape. This distortion causes light to scatter, leading to blurry, distorted, or even double vision.

What Exactly Is Keratoconus?

Keratoconus is a progressive eye condition, typically starting during adolescence or early adulthood — usually between the ages of 10 and 25. It tends to progress over a number of years before stabilising, although for some, progression continues into their 40s or beyond.

The name itself comes from the Greek words *kerato-* (cornea) and *konos* (cone), literally describing the cone-shaped bulge that develops on the eye.

While it used to be classified as a rare disease, recent studies using modern corneal imaging suggest that keratoconus may be far more common than previously thought. Some estimates suggest that it could affect up to 1 in 200 people in certain populations, particularly where diagnostic technology is widely available.

Symptoms of Keratoconus

In its early stages, keratoconus can be subtle. Many people are initially told they simply have astigmatism — a common misdiagnosis — or they notice that their glasses no longer provide the clarity they used to.

The symptoms of keratoconus vary depending on how advanced it is. In the early stages, you might just feel like your vision is a bit off — slightly blurred, maybe double images, or a sense that lights look smeared at night. As the condition progresses, these symptoms worsen. You might become increasingly sensitive to light, struggle to see at night, and find it difficult to read or drive. You may even experience ghosting — where a single object appears to have multiple outlines or shadows. Some people develop a sudden swelling of the cornea, known as corneal hydrops, which can be painful and alarming, though it is relatively rare.

The symptoms usually start in one eye, but both eyes are eventually affected — often to different degrees.

Common symptoms include:

• – Blurred or distorted vision
• – Difficulty seeing clearly at night
• – Glare, halos, or starbursts around lights
• – Increased sensitivity to light
• – Frequent changes in glasses prescription
• – Eye strain or headaches
• – Eye rubbing, often due to irritation

But for many, it’s not just the visual symptoms that are troubling. It’s the emotional confusion. You get a new prescription… but things still don’t feel right. You are told it’s astigmatism, but the lenses never seem to help. You start to feel like something is being missed.

Causes and Risk Factors

People often ask what causes it, and the truth is — it’s complicated. There’s no single cause, but it’s thought to be a combination of genetics, environmental triggers, and mechanical factors like eye rubbing. About 1 in 10 people with keratoconus have a family member who also has the condition. Rubbing your eyes — especially if you have hay fever or allergies — has been strongly linked to the progression of keratoconus. The cornea is made of collagen fibres, and constant pressure can break down this structure over time. That’s why avoiding eye rubbing is one of the first pieces of advice people receive after diagnosis.

Known risk factors include:

• Family history: Around 10–15% of people with keratoconus have a close relative with the condition.
• Eye rubbing: Vigorous or frequent rubbing is strongly linked to the development and progression of keratoconus.
• Allergies and atopic disease: Conditions like eczema, asthma, and hay fever are more common in people with keratoconus.
• Connective tissue disorders: It is also more prevalent among those with Down syndrome or Ehlers-Danlos syndrome.
• Oxidative stress: New research suggests that damage from oxidative stress may weaken corneal tissue.

It’s important to understand that keratoconus isn’t caused by reading in poor light or too much screen time, although those can contribute to eye strain.

Stages of Keratoconus

Keratoconus typically progresses through several stages:

1. Mild (Early Stage)
   Vision may still be corrected with glasses or soft contact lenses.
   Early signs may be misdiagnosed as simple astigmatism.

2. Moderate
   The corneal distortion becomes more pronounced.
   Rigid gas permeable (RGP) or custom contact lenses are usually needed.

3. Advanced
   Vision is severely affected.
   Scarring and thinning of the cornea may occur.
   Surgical options may be necessary.

According to research, around 10–20% of people with keratoconus will eventually require a corneal transplant if the condition progresses significantly. However, the majority manage well with non-surgical treatments.

Diagnosis: What to Expect

Diagnosis involves a few key tests, and if you’ve ever had your eyes scanned with what looks like a camera that maps your cornea in colour, you’ve probably had corneal topography.

1. Corneal Topography: This is the gold standard for diagnosing keratoconus. It creates a detailed, colour-coded map showing the shape and curvature of the cornea.
2. Pachymetry measures the thickness of the cornea, and in keratoconus, thinning is often most pronounced in the lower central area.
3. A slit-lamp examination — using a microscope with a bright light allows detailed inspection of the eye’s surface and helps to identify structural changes like corneal scarring or iron rings near the cone’s base.
4. Anterior segment OCT produces cross-sectional images of the cornea.

Early diagnosis can make a major difference in outcomes. If caught before significant thinning or distortion occurs, treatment can help stabilise the cornea and prevent further progression.

Misdiagnosed Diagnosis

Unfortunately, keratoconus is often missed, especially if you don’t have access to advanced imaging. In some cases, people go for years without a correct diagnosis. This is especially true for teenagers who are assumed to just have fast-changing prescriptions. But those fast changes can be a red flag. Studies have shown that in some regions, the average delay between the onset of symptoms and a proper diagnosis can be 3 to 5 years — valuable time when progression could have been slowed.

The Emotional and Mental Impact

Living with keratoconus can be an emotional rollercoaster, especially when vision changes are fast or when vision can’t be corrected easily. According to a study in the British Journal of Ophthalmology, people with keratoconus often report lower quality of life, particularly related to driving, reading, and general visual function.

Some individuals feel isolated or misunderstood. Others struggle with the idea that their condition might affect their career, education, or independence. This is especially true for young adults managing school or early work life.

Keratoconus doesn’t affect everyone the same way. For some, it stabilises naturally and causes only mild inconvenience. For others, it becomes a constant source of stress — emotionally, visually, and financially. It can interfere with daily life, limit career options, and affect self-confidence, particularly when people feel they can’t explain to others why their vision seems unpredictable or why they’re always getting new lenses. The emotional burden is real, and it’s important to acknowledge that.

But here’s the thing: you’re not alone. Thousands of people around the world are managing keratoconus — and many lead full, active, visually rewarding lives.

Misdiagnosed and misunderstood?

One of the more frustrating aspects of living with keratoconus is that other people often don’t understand it. Friends and family might assume you’re exaggerating or just “need new glasses.” But correcting vision in keratoconus isn’t straightforward. Glasses may work for a while, but as the cornea becomes more misshapen, vision becomes too irregular to correct with lenses alone. Many people eventually move on to rigid gas-permeable lenses, hybrid lenses, or large scleral lenses — each with their own learning curves.

Scleral lenses in particular can be a game-changer. They sit on the white part of the eye (the sclera) and vault over the cornea, providing a smooth refracting surface. Many people experience a dramatic improvement in vision with scleral lenses — often better than they’ve had in years. But they require time to fit properly and can be expensive. Not everyone adapts to them easily.

Keratoconus in Children

Children and teenagers with keratoconus deserve special attention. Studies have shown that keratoconus progresses more aggressively in younger patients. In fact, in some populations, up to 30% of children with the condition progress to an advanced stage within 2 years of diagnosis. Early intervention is essential in paediatric cases, and children should be monitored closely, ideally every few months if progression is suspected.

What treatments are best?

Treatments today are far more effective than they were a decade ago.

1. Glasses and soft lenses are a good solution is early stages.
2. Rigid gas permeable (RGP) lenses – provide a smooth surface over the cornea, improving clarity.
3. Scleral lenses are large lenses that vault over the cornea, offering excellent comfort and vision even in advanced disease.
4. Corneal cross-linking (CXL) is one of the biggest breakthroughs. This minimally invasive procedure uses riboflavin (vitamin B2) drops and ultraviolet light to strengthen the collagen fibres in the cornea, halting or slowing progression. It’s not a cure — it won’t reverse the bulging — but it can stabilise the condition, especially when performed early.
   Cross-linking is now widely used across Europe and has dramatically reduced the number of patients needing corneal transplants. Some studies show that up to 90% of treated eyes remain stable after the procedure, and in some cases, vision even improves slightly over time. Like any medical treatment, there are risks and side effects, but for many, it’s a chance to take control of the disease’s progression.

5. You might also heard about intrastromal corneal ring segments (ICRS), tiny plastic rings inserted into the cornea to flatten its shape. These are most effective in moderate cases and can improve lens tolerance and vision clarity.
6. In more advanced cases, where scarring or extreme thinning makes lenses ineffective, a corneal transplant may be required. Full-thickness or partial-thickness grafts (known as PK or DALK procedures) can restore vision, though recovery takes time and regular monitoring. Success rates are generally high, and many people return to normal or near-normal levels of vision, although most still need corrective lenses.
7. KeraNatural – An innovative human corneal inlay made from reshaped donor tissue. It restores thickness and curvature, helping reshape the cornea without needing full transplantation. Especially, useful for moderate to advanced keratoconus when other interventions are not enough.

No two people experience keratoconus the same way. Some can drive, read, and work normally with well-fitted lenses; others may feel overwhelmed by constant changes and uncertainty. What’s most important is early diagnosis, consistent monitoring, and support — both clinical and emotional.

Keratoconus can be frustrating, even frightening at times, but it’s not the end of clear vision. With the right approach — be it monitoring, lenses, cross-linking, or surgery — most people find a way forward. The journey may involve trial and error, and it may take time to find what works for you, but you are not alone.

There are thousands of others living with keratoconus, sharing their stories, learning what works, and navigating their vision with resilience. And with ongoing advances in eye care, the future for people with keratoconus has never looked clearer.

 Lifestyle Advice: Small Changes, Big Differences

While you can’t cure keratoconus with lifestyle changes, certain habits can help protect your eyes and improve comfort:

• Avoid eye rubbing: Use allergy drops or cold compresses to soothe itchy eyes.
• Treat allergies seriously: Less inflammation means less temptation to rub.
• Hydrate and rest: Corneal cells thrive in a well-hydrated body. Lack of sleep and dehydration may worsen the symptoms.
• Protect from UV: Sunglasses with UV protection help reduce oxidative stress on the cornea.
• Eat for your eyes: Antioxidants like vitamin C, E, and Omega -3s can help support healthy corneal tissue.
• Follow-up regularly: Frequent check-ups help track progression and plan treatment.
• Posture matters: If you find yourself tilting your head or squinting to see, it’s time to revisit your lens fit.

Top 10 FAQs About Keratoconus – Real Questions, Real Answers

1. Why was I told I had astigmatism for years before being diagnosed with keratoconus?
   Astigmatism and keratoconus can look similar in early stages. Both involve irregularities in the cornea that distort vision. But in keratoconus, the changes are progressive and more irregular. If you find your prescription keeps changing or glasses don’t seem to help anymore, it’s a red flag — and one that should prompt corneal topography. Sadly, many people are misdiagnosed for years.

2. Can I wear eye makeup if I have keratoconus or wear scleral lenses?
   Yes — but be careful. Use hypoallergenic, non-waterline eyeliners and avoid fibre mascaras, which can flake into your eyes. Always insert your lenses before applying makeup and remove lenses before removing makeup. Good hygiene is crucial to prevent irritation or infection.

3. Can keratoconus be reversed with supplements or a special diet?
   There’s no known cure or reversal through diet, but nutrition can support eye health. Antioxidants (vitamins A, C, E), omega-3s, and hydration may help maintain corneal tissue health. Some researchers are looking into the role of collagen and oxidative stress in keratoconus, but no supplement replaces proper medical treatment.

4. Can I swim or go to the beach with keratoconus?
   Yes, but if you wear contact lenses (especially RGP or scleral), avoid swimming with them in — or use tight goggles. Saltwater and chlorine can contaminate lenses, and you risk losing one in the water. Always carry glasses or lens solution with you as a backup.

5. Can I work on a computer all day with keratoconus?
   You can, but you may need to make adjustments. Use larger text, reduce screen glare, and follow the 20-20-20 rule: every 20 minutes, look 20 feet away for 20 seconds. Scleral lenses can help maintain clarity throughout the day, but your eyes still need breaks.

6. Is keratoconus considered a disability?
   In some cases, yes — especially if you cannot achieve functional vision with correction. In the UK, for example, individuals with significant vision impairment may qualify for workplace adjustments or disability benefits. It depends on how much the condition limits your daily life.

7. Can I get laser eye surgery if I have keratoconus?
   Traditional laser vision correction like LASIK or PRK is not safe for keratoconus patients because it removes corneal tissue. However, topography-guided PRK or implantable lenses might be considered in highly selective, stable cases. Always consult a corneal specialist.

8. Will pregnancy affect my keratoconus?
   Pregnancy causes hormonal changes that may soften collagen — including in the cornea. Some women report mild progression or changes in lens fit. If you’re pregnant and have keratoconus, let your eye doctor know so they can monitor you more closely.

9. Can I wear contact lenses with keratoconus?
   Yes, many people with keratoconus use specially fitted RGP or scleral lenses.

10. Will keratoconus make me go blind?
    Not completely. But without treatment, vision can be severely reduced. Most people retain functional vision with proper care.

Final Thoughts

Keratoconus may change the way you see the world — but it doesn’t define your future. With modern diagnostics, custom lenses, cross-linking, and supportive care, most people maintain strong vision and lead full, independent lives.

If your vision feels different or your prescription is changing too often, trust your instincts and seek a detailed eye exam. The earlier keratoconus is found, the more treatment options are available — and the more control you’ll have over your visual journey.

You are not alone. And you have options. If you’re concerned about keratoconus and would like to consult with one of our expert consultant ophthalmologists, please get in touch with us at Eye Clinic London.

References:

1. Gomes, J.A.P., Tan, D., Rapuano, C.J., Belin, M.W., Ambrósio, R., Guell, J.L., Malecaze, F., Nishida, K. and Sangwan, V.S., 2015. Global consensus on keratoconus and ectatic diseases. Cornea, 34(4), pp.359–369.
   https://doi.org/10.1097/ICO.0000000000000408
2. Rabinowitz, Y.S., 1998. Keratoconus. Survey of Ophthalmology, 42(4), pp.297–319.
   https://doi.org/10.1016/S0039-6257(97)00119-7
3. Krachmer, J.H., Feder, R.S. and Belin, M.W., 1984. Keratoconus and related noninflammatory corneal thinning disorders. Survey of Ophthalmology, 28(4), pp.293–322.
   https://doi.org/10.1016/0039-6257(84)90094-8
4. McGhee, C.N.J., 2009. 17th Bowman Lecture: 50 years of practical observations on keratoconus: diagnosis, treatment and outcomes. Eye, 23(4), pp.739–755.
   https://doi.org/10.1038/eye.2008.339