Results and repeatability of retinal thickness measurements from certification submissions

Objectives: To present the results for subgroups defined by center point (CP) measurement and to assess the repeatability of the Fast Retinal Thickness Map analysis results from the Stratus OCT3 machine. Methods: Two hundred eighty-one replicate OCT3 scans from 134 operators' certification submissions to a reading center were analyzed, including scans from eyes that were reported to be normal and eyes with exudative age-elated macular degeneration and with macular edema due to diabetic retinopathy or retinal vascular occlusion. Results: The mean (SD) of the CP was 284 (150) mu m and the center subfield (CC) was 301 (130) mu m. The CP coefficient of repeatability (CR) was 49 mu m and the CC CR was 27 mu m. The CR increased by increasing retinal thickness for the CP and the CC within arbitrarily defined subgroups. For the 87 eyes with a session 1 CP of 175 mu m or less, the CP CR was 17 mu m and the CC CR was 10 mu m. Conclusions: Among experienced operators, given the same operator, machine, and eye at the same sitting, OCT3 retinal thickness maps appear to have a CR that is likely to be less than the clinically important difference.