Signs and symptoms of keratoconus may change as the disease progresses. They include:
- Blurred or distorted vision
- Increased sensitivity to bright light and glare, which can cause problems with night driving
- A need for frequent changes in eyeglass prescriptions
- Sudden worsening or clouding of vision
When to see a doctor
See your eye doctor (ophthalmologist or optometrist) if your eyesight is worsening rapidly, which might be caused by an irregular curvature of the eye (astigmatism). He or she may also look for signs of keratoconus during routine eye exams.
If you're considering laser-assisted in-situ keratomileusis (LASIK) eye surgery, your doctor will check for signs of keratoconus before you proceed.
No one knows what causes keratoconus.
These factors can increase your chances of developing keratoconus:
- Having a family history of keratoconus
- Rubbing your eyes vigorously
- Having certain conditions, such as retinitis pigmentosa, Down syndrome, Ehlers-Danlos syndrome, hay fever and asthma
In some situations, your cornea may swell quickly and cause sudden reduced vision and scarring of the cornea. This is caused by a condition in which the inside lining of your cornea breaks down, allowing fluid to enter the cornea (hydrops).
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.