title: Frequency of seeing characteristics of the short wavelength sensitive visual pathway in clinically normal subjects and diabetic patients with focal sensitivity loss.
abstract: OBJECTIVE
  To define the frequency of seeing (FOS) characteristics of the short wavelength (SW) sensitive visual pathway in clinically normal subjects and in diabetic patients with focal SW sensitivity loss.
  
  
  METHODS
  For clinically normal subjects, FOS was assessed at two retinal locations (4.24 degrees and 9.90 degrees eccentricity) for both white on white (WW) and SW stimulus parameters. Inter-examination variability was quantified for the clinically normal subjects only. For patients with diabetes, FOS was assessed inside an area of focal SW sensitivity loss, and at the same eccentricity in the quadrant diametrically opposite, using SW stimulus parameters only.
  
  
  RESULTS
  For clinically normal subjects, the group mean SW FOS slope was significantly flatter (p<0.0001) than that of WW at both locations. The coefficient of repeatability for SW FOS slope was+/-41.55 dB(-1) (relative to a group mean sensitivity of 23.98 dB(-1)) and+/-19.98 dB(-1) (group mean sensitivity 16.15 dB(-1)) for 4.24 degrees and 9.90 degrees , respectively. For the patients with diabetes, the group mean SW FOS slope was significantly flatter (p=0.020), and group mean SW threshold significantly higher (p=0.007) in the area of focal SW sensitivity loss than in that of the non-focal sensitivity loss.
  
  
  CONCLUSIONS
  The results of this study suggest that the clinical utility of SW automated perimetry will be limited by a greater magnitude of measurement variability, as indicated by a flatter FOS slope, compared to conventional automated perimetry.
authors.affiliation: School of Optometry, University of Waterloo, Waterloo, Ontario, N2L 3G1, Canada.
authors.forename: E D
authors.initials: ED
authors.lastname: Gilmore
authors.forename: C
authors.initials: C
authors.lastname: Hudson
authors.forename: R K
authors.initials: RK
authors.lastname: Nrusimhadevara
authors.forename: P T
authors.initials: PT
authors.lastname: Harvey
mesh_terms: D000328:Adult; D000368:Aged; D003930:Diabetic Retinopathy / Q000150:complications / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D012684:Sensory Thresholds; D014786:Vision Disorders / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D058609:Visual Field Tests / Q000379:methods; D014794:Visual Fields; D014795:Visual Pathways