C l i n i c a l s c i e n c e Figure 4 Correlation between the retinal nerve ﬁbre layer (RNFL) as measured with GDx enhanced corneal compensation (ECC) and the inferior angle. The slopes of the regression lines (K) together with the limits of the 95% CI of the slopes are plotted against the 64 sectors (plots). Statistical signiﬁcance of the slope is reached when the 95% CI does not include the zero line. The sections of the TSNIT (temporalesuperiorenasale inferioretemporal) graph marked with a bold line symbolise signiﬁcance of Pearson R. interindividual variation in RNFL proﬁles may lead to an improvement of speciﬁcity and sensitivity of RNFL measure- ments. The application of a normative database, taking into account the position of major blood vessels, might therefore improve the diagnostic power of RNFL measurement. Competing interests None. Patient consent Obtained. 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