Keratoconus (KC) is a complex corneal disorder characterized by progressive thinning and cone-shaped protrusion of the cornea. A recent review reported that the prevalence of KC ranged
from 0.2 to 4 790 per 100,000 worldwide. KC is usually accompanied by varying degrees of visual impairment, leading to blindness in severe cases. The exact etiology of KC is still unclear. Multiple genetic studies have indicated that genetic components play important roles in KC. In addition,
environmental factors, which include age, gender, ethnicity, ultraviolet exposure, atopy, and eye rubbing, have been recognized to be associated with KC. Identifying and controlling the
modifiable risk factors of KC would help reduce the incidence of KC, and further decrease its economic burden for the society.
