Keratoconus is a condition in which the usually round cornea begins to take on an asymmetric and irregular cone-like shape. The disease, which is very frequently familial, is not presented at birth but has a later onset, between 10 and 20 years of age.

Keratoconus has an evolutionary course during which the cornea becomes progressively thinner and is unable to maintain its round shape. This causes a loss of vision which cannot be corrected by wearing glasses. In cases of worsening astigmatism, corneal topographic analysis is always advisable to allow early diagnosis.

Techniques are available to treat keratoconus that aim to arrest its progression (corneal crosslinking). The efficacy of the treatment is directly related to how early the diagnosis is made.