Your browser does not support javascript:   Search for gard hereSearch for news-and-events here.


Genetic and Rare Diseases Information Center (GARD)

Print friendly version

Epithelial basement membrane corneal dystrophy

Other Names for this Disease
  • Cogan corneal dystrophy
  • Corneal dystrophy, anterior basement membrane
  • Map-dot-fingerprint dystrophy of cornea
  • Microcystic dystrophy of the cornea
See Disclaimer regarding information on this site. Some links on this page may take you to organizations outside of the National Institutes of Health.


Newline Maker

What are the signs and symptoms of epithelial basement membrane corneal dystrophy?

A chronic problem seen in this condition is the epithelial erosions. They can alter the cornea's normal curvature, causing periodic blurred vision. These erosions may also expose the nerve endings that line the tissue, resulting in moderate to severe pain lasting as long as several days. Generally, the pain will be worse upon awakening in the morning. Other symptoms include sensitivity to light, excessive tearing, and foreign body sensation in the eye. This condition usually affects adults between the ages of 40 and 70, although it can develop earlier in life.[1]

It gets its name from the unusual appearance of the cornea during an eye exam. Most often, the affected epithelium will have a map-like appearance, i.e., large, slightly gray outlines that look like a continent on a map. There may also be clusters of opaque dots close to the map-like patches. Less frequently, the irregular basement membrane will form concentric lines in the central cornea that resemble small fingerprints.[1]

Epithelial basement membrane corneal dystrophy is not a progressive condition. Typically, it will flare up occasionally for a few years and then go away on its own, with no lasting loss of vision. Most people never know that they have this condition, since they do not have any pain or vision loss.[1][2]
Last updated: 6/30/2011

  1. Facts About the Cornea and Corneal Disease. National Eye Institute (NEI). June 2011; Accessed 6/30/2011.
  2. Verdier D & Roy H. Dystrophy, Map-dot-fingerprint. eMedicine. May 2009; Accessed 6/30/2011.
  3. Corneal dystrophy, epithelial basement membrane; EBMD. Online Mendelian Inheritance of Man (OMIM). 2009; Accessed 6/30/2011.