Keratoconus at a molecular level: a review.

Keratoconus is the most common ectatic disease of the cornea. The disease is usually detected between ages 15 and 25. Incidence is estimated at one out of every 2000 individuals, with some specific ethnic groups being more at risk. Keratoconus manifests itself as a progressive stromal thinning and deformation of the corneal tissue into a conical shape. The etiology of keratoconus is uncertain, although several studies have associated the disease to environmental factors, behavioral conditions and certain genetic disorders. In an effort to better understand how the corneal stroma becomes compromised, multiple experiments have been conducted over the last few years looking at the cells themselves and the factors they produce. The secretion pathways and levels of inflammatory molecules, growth factors, digestive enzymes, and apoptotic factors are all relevant to keratoconus. This review describes the current knowledge of keratoconic pathological signaling pathways within the cornea that may help future developments in disease prevention, treatment and modeling. Anat Rec, 2019. (c) 2019 Wiley Periodicals, Inc.