Symptoms of keratoconus generally begin in late teenage years or early twenties, but can start at any time.

Symptoms of keratoconus Keratoconus can sometimes cause night vision complaints due to halos and glare.

The earliest signs of keratoconus are typically:

  • Blurry vision
  • The need to frequently change a prescription.
  • Blurred vision that cannot be corrected with glasses.

Other symptoms include:

  • Increased light sensitivity
  • Difficultly driving at night
  • Halos and glare especially at night
  • Eye strain
  • Headaches and general eye pain
  • Eye irritation

In the advanced stages of keratoconus, the patient may experience a sudden clouding of vision in one eye that clears over a period of weeks or months. This is called "acute hydrops" and is due to the sudden infusion of fluid into the stretched cornea. In advanced cases, superficial scars form at the apex of the corneal bulge resulting in more vision impairment.