Keratoconus- Keratoconus causes structural changes within the cornea, which causes it to thin and become more cone shaped than the normal gradual curve. Keratoconus is a degenerative disorder of the eye which can require surgery. However, for many patients, contact lenses are an effective alternative to surgery. In most cases, contact lenses provide superior vision to glasses.
Aphakia- Aphakia is the absence of the lens inside the eye. This can be a result of surgical removal, trauma or genetic abnormalities. Aphakia may be corrected by contact lenses, glasses, or by an artificial lens implant.