title: Rasterstereography-based classification of normal corneas.
abstract: OBJECTIVE
  To attempt to classify the topographic patterns identified by rasterstereography in a population with normal corneas.
  
  
  METHODS
  Tulane Medical Center Clinic, New Orleans, Louisiana.
  
  
  METHODS
  Corneal elevation pictures of 100 eyes of 50 volunteers were taken using the PAR Corneal Topography System. The volunteers had no history of eye injury, disease, or surgery, and none wore contact lenses. Three observers independently assigned the images to one of five subgroups.
  
  
  RESULTS
  Five categories were identified: unclassified, regular ridge, irregular ridge, incomplete ridge, and island. There were significant statistical differences in the degree of astigmatism between the irregular ridge and incomplete ridge groups (P = .0419) and between the irregular ridge and island groups (P = .017).
  
  
  CONCLUSIONS
  The topographic patterns identified by rasterstereography in normal corneas can be classified into five distinct groups.
authors.affiliation: Department of Ophthalmology, Tulane Medical Center, New Orleans, Louisiana 70112, USA.
authors.forename: S C
authors.initials: SC
authors.lastname: Naufal
authors.forename: J S
authors.initials: JS
authors.lastname: Hess
authors.forename: M H
authors.initials: MH
authors.lastname: Friedlander
authors.forename: N S
authors.initials: NS
authors.lastname: Granet
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003315:Cornea / Q000033:anatomy & histology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000145:classification* / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012016:Reference Values