title: Cup size predicts subsequent functional change in early glaucoma.
abstract: OBJECTIVE
  To identify structural predictors of functional change in patients with early glaucoma or risk factors for development of glaucoma.
  
  
  METHODS
  One hundred twenty-nine participants with either high-risk ocular hypertension, suspected, or early glaucoma were followed for 10 annual visits. Standard Automated Perimetry was performed at each visit, along with Confocal Scanning Laser Ophthalmoscopy (CSLO). Mean deviation (MD) at the same visit and the subsequent rate of change in MD were predicted by linear regression models based on CSLO parameters along with intraocular pressure, central corneal thickness, and treatment status. Models were assessed by comparing the correlations between predicted and observed perimetric results.
  
  
  RESULTS
  The model using rim area predicted MD at the same visit with correlation 0.445. Using cup area, the equivalent correlation was r = 0.411, lower than the model using rim area with p = 0.096. Using cup volume, the correlation was r = 0.436, and the comparison had p = 0.714; using disc area r = 0.396 and p = 0.011. The model using rim area to predict the subsequent rate of change of MD had r = 0.539. Models using cup area (r = 0.631), cup volume (r = 0.649), or disc area (r = 0.602) were significantly better; p = 0.003, p = 0.001, and p = 0.044, respectively.
  
  
  CONCLUSIONS
  Lower rim area, as measured by CSLO, is predictive of worse function when measured on the same date in participants with high-risk ocular hypertension, suspected, and early glaucoma. However, cup area, cup volume, and disc area may all be more predictive of the rate of subsequent functional change. Parameters should be chosen based on the specific purpose intended and questions asked, rather than using the same parameters in all circumstances.
authors.affiliation: Discoveries In Sight Laboratories, Devers Eye Institute, Legacy Health, Portland, Oregon 97232, USA. sgardiner@deverseye.org
authors.forename: Stuart K
authors.initials: SK
authors.lastname: Gardiner
authors.forename: Chris A
authors.initials: CA
authors.lastname: Johnson
authors.forename: Shaban
authors.initials: S
authors.lastname: Demirel
mesh_terms: D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D005901:Glaucoma / Q000473:pathology* / Q000503:physiopathology; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D009887:Ophthalmoscopy; D009898:Optic Disk / Q000473:pathology*; D011379:Prognosis; D013997:Time Factors