13971 W Preserve Blvd Burnsville, MN 55337

Symptoms of Keratoconus

The first symptom of keratoconus is usually blurred vision which occurs over the course of several months or even years. The blurred vision is almost always more pronounced in one eye more than the other eye. This can make early diagnosis of keratoconus more difficult as patients may not notice the loss of vision as the lesser affected eye will sometimes completely compensate for the more effected eye.

Since no cornea is perfectly round, everyone has some degree of a “football shaped” cornea which induces astigmatism resulting in widely varying degrees of blurred vision.  This can usually be corrected with glasses or standard contact lenses. Astigmatism also causes ghost images which are especially noticeable at night. In cases of keratoconus, the cornea becomes extremely football shaped inducing high amounts of “irregular” astigmatism causing multiple curves and areas of distortion. This will then result in multiple ghost images and blurred vision not correctable by glasses or contact lenses.

Another initial symptom of keratoconus is poor night vision.  No one sees well at night even with the best corrective lenses in place. However, keratoconus patients have much more difficulty at night as the multiple ghost images from car lights, street lights and other light sources distort the images entering the eyes. These symptoms are less noticeable during the day as natural light sources provide more even lighting which result in less ghost images and distortion. Pupil size also plays an important role in ghost imaging and blur as a bigger pupil (with low light at night) will allow more irregular images into the eye compared to a pupil that is constricted and smaller with more light during the day.

Since keratoconus can be difficult to diagnose, patients are often given glasses or contact lens prescriptions which can partially correct the blurred vision but the ghost images still remain. This is why it is important to further evaluate patients who have persistent blurry vision even when they are wearing corrective lenses.

Painful? Keratoconus is usually painless except in more advanced cases where the corneal surface completely loses its integrity and significant swelling occurs which is rare. Occasionally the keratoconus cornea can become dry with some minor burning and stinging.  Sensitivity to bright lights, headaches, and squinting are also other common symptoms.

Most symptoms of keratoconus can be relieved with proper treatment to slow or stop the progression of the condition. However, if the severity of the keratoconus is allowed to worsen to the point of corneal scarring, the symptoms may be permanent and not correctable even with new scleral contact lenses. This leaves only a corneal transplant to relieve the symptoms.

Learn About Keratoconus Treatment Options