Eye
Cornea
Keratoconus

Author: Nat Pernick, M.D. (see Authors page)

Revised: 3 May 2018, last major update October 2013

Copyright: (c) 2004-2018, PathologyOutlines.com, Inc.

PubMed Search: Keratoconus [title] pathology [title]

Cite this page: Pernick, N. Cornea: keratoconus. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/eyecorneakeratoconus.html. Accessed December 17th, 2018.
Definition / general
  • Common, incidence of 1 per 2000
  • Congenital ectasia of central cornea, usually identified by age 9 years
  • Usually bilateral
  • Associated with Down syndrome, Marfan syndrome and atopic disorders
  • Progresses until fibrosis decreases vision
  • May have sudden rupture of Descemet membrane, allowing aqueous humor to enter corneal stroma, causing corneal hydrops and sudden worsening of vision
  • Causes scarring and astigmatism which cannot be corrected by glasses; may be corrected by rigid contact lenses
Treatment
  • Corneal transplantation
Gross description
  • Wrinkled corneal button after transplantation
  • Cornea is cone shaped
  • Often has Fleischer ring (brown, stainable intraepithelial iron arc surrounds conical portion of cornea)
Microscopic (histologic) description
  • Thinning and fibrosis of cornea
  • Numerous breaks in Bowman layer
  • No inflammation or vascularization