Measurement of optic nerve head pallor with a video-ophthalmograph and with computerized boundary analysis.

Optic disc pallor was recorded in 53 eyes of 53 patients by means of global analysis with a video-ophthalmograph (Rodenstock Disk Analyzer) and computerized boundary analysis. The coefficients of correlation between the values obtained with the Rodenstock Disk Analyzer and those obtained with boundary analysis were r = 0.24 (p = 0.08) at the 0.29 cutoff level, r = 0.39 (p = 0.004) at the 0.39 level and r = 0.46 (p = 0.0005) at the 0.50 level. Although the correlation was significant, the correlation coefficients were not high. The Rodenstock Disk Analyzer uses global analysis, which does not take into account the spatial relationship of the pallor on the disc, whereas boundary analysis is sensitive to spatial relationship, which may account for the poor correlation.