Fig. 2

pRNFL sector/field test scatterplots and principal curves for all glaucoma eyes. Data points are plotted as semi-transparent (grey markers ), therefore darker areas indicate higher concentrations of overlapping points. “ρ” (Spearman correlation coefficients) and “n” (number of points in the correlation) values shown at bottom right of each plot are across all glaucoma subjects. All correlations are significant at p < 0.0001. Also shown are the data for the glaucoma patient with the highest total correlations ( , ). Correlations for individual subjects varied between strong correlations in some, e.g. left ( ) and right ( ) eyes of the glaucoma patient shown (mfPOP LumBal: ρ = 0.84, Lum + Col: ρ = 0.81, LumBal + Col: ρ = 0.82; HFA: ρ = 0.80), to zero or negative correlations in others. As with the data points, principal curve outputs are shown as semi-transparent (red markers ). These reveal non-linearities in the relationship between pRNFL and field sensitivities, this being most pronounced in SAP