Symptoms, Causes, Treatments, Questions & Related Topics

Possible Symptoms for Keratoconus

1. Blurry or distorted vision

Keratoconus is a progressive eye disease that causes the cornea to become incredibly thin and to bulge outward, which makes it become cone-shaped.[1] One of the early symptoms of keratoconus is mild vision blurring. Distorted vision can also occur, which can create issues like lines that are straight appearing to be wavy or bent. Over time, vision can become more distorted and blurrier.[2]

2. Sensitivity to light

Early stages of keratoconus can lead to sensitivity to light as well as to the glare that can bounce off of shiny surfaces. This can worsen over time, making it uncomfortable to go outside and especially to drive at night. The symptoms usually take years to worsen but, in certain individuals, they can come on quickly.[2]

3. Redness or swelling

The eyes can become red or swollen as a result of keratoconus. This can also happen early in the illness’s development or over a longer period of time.

4. Worsened eye conditions

Nearsightedness or astigmatism often go hand-in-hand with keratoconus. Unfortunately, the latter condition can worsen the former, requiring you to update your eyeglass prescription more often. The changes that occur to the way your eye is shaped can make it difficult to wear regular contact lenses in the later stages of keratoconus.

Top 5 Causes of Keratoconus

1. Unknown

Doctors are unsure what causes keratoconus. The condition itself is rare, although those who have a tendency toward the condition may find that it is present at birth.[3]

2. Collagen defect

It could be possible that those who develop keratoconus do so because of a defect in their body’s ability to create collagen.[3] Collagen is the tissue that strengthens and shapes the cornea of the eye, so those who have trouble producing collagen naturally could potentially experience shifts and changes in the strength and shape of the cornea.

3. Heredity

It seems possible that keratoconus may be a hereditary condition. About 1 in 10 people who are diagnosed with keratoconus also are related to someone, usually a parent, with the condition.

4. Rubbing eyes

Allergies can cause a person to rub their eyes frequently and forcefully, which may be a cause of keratoconus. Those who rub their eyes forcefully for other reasons may also develop this condition.

5. Other conditions

Other risk factors may have to do with certain medical conditions, such as Ehlers-Danlos syndrome, Down syndrome, retinitis pigmentosa, or asthma. Those who have any of these conditions are more at risk of developing keratoconus.

2 Ways to Prevent Keratoconus

1. Protect your eyes

This is one of the only things you can do to prevent keratoconus. Those who rub their eyes frequently or who have had a history of wearing poorly fitted contacts could potentially develop the condition as a result.[4] As such, you’ll want to make sure you don’t wear novelty contact lenses or lenses meant for someone else. You should also avoid vigorously rubbing your eyes.

2. See an eye doctor

Keratoconus requires a diagnosis from an eye doctor, and one of the best ways to make sure you don’t have a worsening condition is to see your eye doctor regularly. Your doctor will be able to recognize the signs of keratoconus as well as start treatment immediately if the condition has already occurred, which can help keep it from getting worse.

Possible Keratoconus Treatment Options

1. New glasses or contacts

Glasses can often be used to correct the issues caused by keratoconus if the symptoms are mild.[4] However, if you need an option that actually helps strengthen your cornea, or if you prefer to wear contact lenses, there are other options available. For example, gas permeable contact lenses are harder and can help strengthen the cornea. These are much more rigid than regular, soft contacts, so they can be uncomfortable at first, but most people adjust to them after a couple of weeks. Other contact lens options include piggy-back contact lenses, scleral, and semi-scleral contact lenses.[1]

2. Intacs

Intacs are curved devices that are surgically placed in your cornea by your ophthalmologist.[5] These devices help make the cornea flatter and remove some of the cone-shape curve caused by the keratoconus, which makes it easier for you to see. However, this treatment and those mentioned below are usually only used to treat later stage keratoconus.

3. Collagen cross-linking

This is a treatment option that uses UV light rays and eye drops to cause the cornea to make the cornea flatter, stronger, and stiffer so that it stops bulging out as far.[5] This treatment method is practiced by an ophthalmologist.

4. Corneal transplant

Severe symptoms may require a more intensive treatment option like a corneal transplant. This is usually only performed if your cornea cannot be repaired and if the symptoms of the keratoconus are worsening exponentially.[6] Corneal transplantation requires that your ophthalmologist replace either all or part of the cornea with donor tissue from another cornea.

Questions Your Doctor May Ask about Keratoconus

  • How long have you been experiencing symptoms of keratoconus?
  • Are you nearsighted?
  • Do you have astigmatism?
  • Do you have trouble seeing or driving while outside or at night?
  • Do you wear contacts or glasses?
  • Has anyone in your family ever had keratoconus?
  • Do you have any chronic conditions such as asthma, allergies, or others that could be risk factors for keratoconus?
  • Have you noticed your symptoms worsening over time?

Keratoconus May Also be Known as:

  • Conical cornea
  • Progressive thinning of the cornea


  1. Eye Health Web. Keratoconus.
  2. American Academy of Ophthalmology. Keratoconus Symptoms.
  3. National Library of Medicine. Keratoconus.
  4. Cedars Sinai Medical Center. Keratoconus.
  5. American Academy of Ophthalmology. Keratoconus Treatment.
  6. American Academy of Ophthalmology. About Corneal Transplantation.

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