Keratoconus

Keratoconus is an eye condition that happens when the corneas in your eyes bulge out into a cone shape. Normally, corneas are rounded, like domes.

If you have keratoconus, your corneas change shape slowly over time. Eventually, they won’t bend light that enters your eye like they should. This can affect your vision. It can make you more nearsighted and cause irregular astigmatism.

An eye doctor might diagnose keratoconus before you have any symptoms. This condition sometimes takes years to develop. It’s most commonly diagnosed in teens and young adults, but you can develop it at any age.

Symptoms of keratoconus

Keratoconus symptoms include:

• Gradually worsening vision, usually in both eyes
• Distorted vision that makes straight lines look curved, bent or wavy
• Double vision when you have one eye closed
• Seeing halos or sunburst shapes around bright lights, like headlights or street lamps
• Light sensitivity

Keratoconus usually happens in both eyes at the same time. But it can sometimes affect only one eye, or one eye more than the other.

Keratoconus causes

Experts aren’t sure what causes keratoconus. It usually develops on its own without an obvious cause. It might run in biological families. But researchers haven’t been able to prove for sure that it’s a genetic condition.

There’s an association between rubbing your eyes a lot and having keratoconus. So, you might have a higher risk if you have allergies, dry eye or another health condition that makes you want to rub your eyes more often than usual. But experts haven’t been able to prove this link. It might just be a coincidence.

Keratoconus complications

Complications are rare. But untreated keratoconus can increase your risk of:

• Cornea scars
• Corneal hydrops
• Vision loss

How doctors diagnose keratoconus

An eye doctor will diagnose keratoconus with an eye exam. They’ll check your eyes inside and out. Tell them about any symptoms or changes you’ve noticed. Let them know if your vision has changed, and how quickly it seemed to happen.

You might need specific tests, like keratometry and corneal topography. This will help your eye doctor check the exact shape and curve of your corneas and diagnose keratoconus and astigmatism.

Keratoconus treatments

Your eye doctor will suggest treatments that help you see clearly and manage keratoconus. Some of the most common treatments include:

• Wearing glasses or contact lenses: These will correct your vision. Your eye doctor may suggest a special type of hard (rigid gas permeable) contact lenses that gently squeeze your eyes to slow down changes in your corneas. Eventually, you may need other treatments if your corneas keep changing.
• Corneal cross-linking: This procedure uses focused UV lights to strengthen your corneas. This can stop them from changing shape.
• Implantable ring segments (Intacs®): An eye surgeon will insert Intacs into your corneas. They act kind of like braces for inside your eyes. Instead of realigning your teeth, Intacs flatten your corneas.
• Corneal transplants: Your eye doctor may suggest transplants if you have severe keratoconus and other treatments haven’t worked. An eye surgeon will remove your corneas and replace them with ones from a donor.

When should I see my healthcare provider?

Visit an eye doctor as soon as you notice any changes in your eyes or vision. Especially if your vision suddenly gets worse.

Your eye doctor will tell you how often you’ll need eye exams in the future. They’ll monitor any changes in your eyes and make sure your treatments are working.

What can I expect if I have keratoconus?

Keratoconus usually responds well to treatment. If you have a mild case, you may only need glasses or contacts. But you might need an updated prescription more often than usual. Your eye doctor will tell you what to expect.

Your eyes naturally change throughout your life, and that’s also true if you have keratoconus. You may need more or different treatments later, even if you only needed glasses or contacts at first.

Your vision might be worse or blurry for a few days after corneal cross-linking or getting Intacs, but it should clear up as you recover.