title: Comparison of keratometric values of healthy and diseased eyes measured by Javal keratometer, EyeSys, and PAR.
abstract: OBJECTIVE
  To compare the simulated keratometric results of the PAR CTS and the EyeSys corneal imaging systems with Javal keratometer readings in keratoconus eyes, in eyes after corneal grafting, and in healthy eyes.
  
  
  METHODS
  Cornea Service, Wills Eye Hospital, Philadelphia, Pennsylvania, USA.
  
  
  METHODS
  This prospective study evaluated 69 patients divided into three groups (keratoconus; 6 to 12 months postkeratoplasty; normal corneas) treated at the cornea service. The eyes were measured with each of the three instruments. Keratometry results and number of attempts needed to obtain the results were collected.
  
  
  RESULTS
  Thirty keratoconus, 18 transplanted, and 21 normal corneas were examined. The PAR CTS Imaged all corneas and the EyeSys, 86% (P = .000627). The PAR CTS and Javal flat and steep K-readings in all three groups were the same. The EyeSys simulated keratometry results were lower than those of Javal keratometer in the flat K (P < .00001) and steep K (P < .00001) in the normal group and in the steep K in the transplanted cornea group (P = .00823). The EyeSys also measured less astigmatism than the Javal in the normal (P = .00124) and transplanted cornea groups (P = .00376).
  
  
  CONCLUSIONS
  The PAR CTS was better able than the EyeSys to provide keratometric values that agreed with those obtained with the Javal keratometer.
authors.affiliation: Cornea Service, Wills Eye Hospital, Philadelphia, Pennsylvania 19107-5598, USA.
authors.forename: D
authors.initials: D
authors.lastname: Varssano
authors.forename: C J
authors.initials: CJ
authors.lastname: Rapuano
authors.forename: J I
authors.initials: JI
authors.lastname: Luchs
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001251:Astigmatism / Q000175:diagnosis; D002102:Cadaver; D003315:Cornea / Q000473:pathology* / Q000601:surgery; D016039:Corneal Transplantation / Q000473:pathology; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007640:Keratoconus / Q000473:pathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009885:Ophthalmology / Q000295:instrumentation*; D011184:Postoperative Period; D011446:Prospective Studies; D012029:Refraction, Ocular