We see through the cornea, which is the clear outer lens or “windshield” of the eye. Normally, the cornea has a dome shape, like a ball. Sometimes, however, the structure of the cornea is just not strong enough to hold this round shape and the cornea bulges outward like a cone. This condition is called keratoconus.

What causes Keratoconus?

Often the cause of keratoconus is unknown, though Keratoconus may be associated with:

    • Vigorous rubbing of your eyes
    • Other eye conditions, including retinitis pigmentosa, retinopathy of prematurity or vernal keratoconjunctivitis
    • A combination of several disorders, such as enzyme abnormalities or hereditary factors including Down syndrome
    • Wearing contact lenses for several years
    • Genetic predisposition

Your eye care physician may look for signs of Keratoconus during your routine eye examinations.

What are the symptoms of Keratoconus?

Signs and symptoms of keratoconus may change as the disease progresses. They include:

  • Blurred or distorted vision
  • Increased sensitivity to bright light and glare
  • Problems with night vision
  • Many changes in eyeglass prescriptions
  • Sudden worsening or clouding of vision, caused by a condition in which the back of your cornea ruptures and fills with fluid (hydrops)
You should make an appointment to see your eye doctor as soon as possible if you have irregular curvature of the eye (astigmatism) and your eyesight is worsening rapidly.


What if I do not treat my Keratoconus?

In some situations, your cornea may swell quickly and cause sudden reduced vision and scarring of the cornea. In advanced keratoconus, your cornea may become scarred, particularly where the cone forms. A scarred cornea causes worsening vision problems and may require corneal transplant surgery.

While Keratoconus does not make people go blind, the changes to the cornea will make it impossible for the eye to focus without eyeglasses or contact lenses. Keratoconus patients are NOT eligible for LASIK or PRK as these two procedure remove tissue from the cornea in order to reshape it to the desired curvature which would further weaken the structural integrity of the cornea and worsen the progression of keratoconus.

Are there surgical procedures to treat Keratoconus?

A small number of cases of keratoconus keep getting worse, however, and, eventually, contact lenses cannot give clear vision. In other cases, the keratoconus or the use of contact lenses over the years will have side effects. These side effects can make the cornea cloudy. When these things happen, corneal transplantation might be recommended.

Are there non-surgical procedures to treat Keratoconus?

Treatment usually starts with new eyeglasses, and then contact lenses are recommended. These will correct the vision problems caused by keratoconus.

Keratoconus changes vision in two ways:

  • As the cornea changes from a ball shape to a cone shape, the smooth surface also becomes slightly wavy. This is called irregular astigmatism .
  • As the front of the cornea expands, the eye becomes more nearsighted . That is, only nearby objects can be seen clearly. Anything too far away will look like a blur.

New eyeglasses can usually make vision clear again in mild cases of keratoconus. Eventually, though, it will probably be necessary to use contact lenses. Rigid lenses are used most frequently in keratoconus patients.