Interobserver variability in optical coherence tomography for macular edema.

PURPOSE: To assess the interobserver variability of optical coherence tomography (OCT) measurements in patients with macular edema.
DESIGN: Noninterventional case series using a diagnostic instrument.
METHODS: Ordinary least products analysis of OCT data obtained by two masked observers from a set of 20 eyes from 10 patients.
SETTING: Private retina practice.
RESULTS: Foveal zone thickness measurements were operator dependent. Fixed and proportional bias was found between the two observers. Total macular volume measurements were independent of observers.
CONCLUSION: Foveal zone thickness measurements are not directly comparable across different observers, but total macular volume measurements are directly comparable. Multicenter studies involving OCT measurements and clinical users of OCT data will need to factor interobserver variability into conclusions drawn from pooled OCT foveal zone thickness measurements.