title: Trends in the indications for penetrating keratoplasty in the midwestern United States.
abstract: OBJECTIVE
  To examine the leading indications and identify the changing trends for penetrating keratoplasty (PKP) in the midwestern United States.
  
  
  METHODS
  The indications for PKPs at a single center tertiary care referral practice were tabulated to assess trends from 1982 to 1996. The data analysis was prospective after 1985. Age, gender, clinical indication for PKP, date of surgery, status of the lens at the time of surgery (phakic, aphakic, pseudophakic, cataract), and any secondary diagnoses were recorded. In pseudophakic eyes, the type of intraocular lens (IOL) present at the time of surgery was noted. Correlation analysis and linear regression were used in the SAS system, version 6.12, to test for the statistical significance in increasing or decreasing trends over the span of the study.
  
  
  RESULTS
  A total of 4,217 PKPs were performed on 3,263 patients. The leading indication for PKP was pseudophakic bullous keratopathy (31.5%), with 73% of these cases associated with an anterior chamber IOL, 21% associated with a posterior chamber IOL, and 6% associated with an iris-fixated IOL. Fuchs' dystrophy (23.2%), keratoconus (11.4%), corneal scarring (11.2%), failed graft (8.9%), and aphakic bullous keratopathy (7.5%) followed pseudophakic bullous keratopathy in frequency. These six groups accounted for approximately 93% of all cases performed. There were significant increasing trends in the incidence of failed grafts (p = 0.0001) and corneal scarring (p = 0.0001), and decreasing trends in the incidence of aphakic bullous keratopathy (p = 0.0001). There was a significant decreasing trend in pseudophakic bullous keratopathy from 1989 to 1996 (p = 0.0031).
  
  
  CONCLUSIONS
  Pseudophakic bullous keratopathy was the leading indication for PKP in our series. This is in agreement with the data reported in other similar studies done in North America. However, unlike most of these studies, our second leading indication was Fuchs' dystrophy. This contrast may be secondary to different genetic demographics in the midwestern United States.
authors.affiliation: Cornea Research Foundation of America, Indianapolis, Indiana, USA.
authors.forename: K R
authors.initials: KR
authors.lastname: Dobbins
authors.forename: F W
authors.initials: FW
authors.lastname: Price
authors.forename: W E
authors.initials: WE
authors.lastname: Whitson
mesh_terms: D000328:Adult; D000368:Aged; D003315:Cornea / Q000473:pathology; D003316:Corneal Diseases / Q000453:epidemiology* / Q000473:pathology / Q000601:surgery; D005260:Female; D006801:Humans; D015994:Incidence; D015948:Keratoplasty, Penetrating / Q000639:trends*; D008297:Male; D008875:Middle Aged; D015146:Midwestern United States / Q000453:epidemiology; D012189:Retrospective Studies; D012720:Severity of Illness Index