title: Analysis of the relationship between drusen size and drusen area in eyes with age-related macular degeneration.
abstract: OBJECTIVE
  To examine the relationship between drusen counts and drusen area in eyes with age-related macular degeneration, and to correlate drusen areas between fellow eyes.
  
  
  METHODS
  Digital images from 378 patients (756 eyes) were analyzed using a validated drusen detection algorithm. Total drusen area and the number of drusen of various sizes (small: < 62 microns, intermediate: 63-124 microns, large: 125-249 microns, etc) were recorded for the central 1,000- and 3,000-micron diameter macular regions. Correlations were assessed using structural equation models.
  
  
  RESULTS
  For the 1,000-micron region, the number of intermediate drusen was more highly correlated to total drusen area than the number of large drusen (R = 0.91 vs 0.82); this difference was statistically significant. The correlation coefficients for drusen area between fellow eyes was 0.73.
  
  
  CONCLUSIONS
  The number of large drusen does not correlate better with total drusen area than drusen of other sizes. The number of large drusen is not necessarily a good surrogate for total drusen area.
authors: UPMC Eye Center, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA. friberg@pitt.edu
authors: Thomas R
authors: TR
authors: Friberg
authors: Richard A
authors: RA
authors: Bilonick
authors: Peter M
authors: PM
authors: Brennen
mesh_terms: D000465:Algorithms; D005260:Female; D005584:Fovea Centralis / Q000473:pathology; D006801:Humans; D008268:Macular Degeneration / Q000150:complications / Q000473:pathology*; D008297:Male; D015593:Retinal Drusen / Q000473:pathology*; D014792:Visual Acuity