Keratoconus is a degenerative disorder of the eye which is thought to occur in roughly 1 out of every 2,000 persons. It refers to a process in which structure changes within the cornea cause it to become thinner and develop into a conical shape in contrast to the regular gradual curve. Keratoconus can require surgery, even a corneal transplant, though catching it early often means needing nothing more than corrective glasses or contact lenses.
That means that catching the condition early is always advantageous, so it's important to know the signs. Here are four of the most common early symptoms of keratoconus.
1. Greater Sensitivity to Light
Sensitivity to light, known more correctly as photophobia, is a common side effect of keratoconus. It occurs because the changed shape of the cornea causes light entering the eye to scatter in unexpected directions. If this does occur, make sure you avoid fluorescent lights and turn down the brightness level on computers and mobile devices until you have a chance to see an optometrist.
2. Haloes Around Lights
Just as the scattering of light in different directions that occurs when the cornea's shape is compromised can cause photophobia, it can also create strange visual effects, even if you don't actually feel any sensitivity. You may notice that light sources appear to have haloes, multiple images, or circles of glare surrounding them. This effect is most likely to occur during the night, and it can make driving unsafe.
3. Ghosting or Double Vision
Ghosting or double vision often occurs due to changes in the way light enters the eye. You may find that several images of the same object appear at once around the same place, almost as if several pictures had been imposed almost, but not quite, on top of each other. Lines may be blurry, and you could find yourself becoming dizzy after viewing objects in this way.
4. Eye Strain
Finally, the changing shape of the cornea can cause eye strain, even if you don't notice any changes to your actual vision. Your eyes may feel painful, and this discomfort could be accompanied by headaches, particularly after you've been reading, looking at a computer screen, driving, or partaking in any activity that requires persistent focusing. If you notice that you've been rubbing your eyes more frequently, keratoconus could be the cause.
Keratoconus is rare enough to mean that most people don't even know of its existence, but it's still common enough to ensure that knowing the symptoms is smart. If you notice any of the signs above presenting themselves, make sure you visit an optometrist as soon as possible.