We demonstrate significantly different scattering coefficients of the retinal nerve fiber layer (RNFL) between normal and
glaucoma subjects. In clinical care, SD-OCT is routinely used to assess the RNFL thickness for glaucoma management.
In this way, the full OCT data set is conveniently reduced to an easy to interpret output, matching results from older (non-
OCT) instruments. However, OCT provides more data, such as the signal strength itself, which is due to backscattering in
the retinal layers. For quantitative analysis, this signal should be normalized to adjust for local differences in the intensity
of the beam that reaches the retina. In this paper, we introduce a model that relates the OCT signal to the attenuation
coefficient of the tissue. The average RNFL signal (within an A-line) was then normalized based on the observed RPE
signal, resulting in normalized RNFL attenuation coefficient maps. These maps showed local defects matching those found
in thickness data. The average (normalized) RNFL attenuation coefficient of a fixed band around the optic nerve head was
significantly lower in glaucomatous eyes than in normal eyes (3.0mm-1 vs. 4.9mm-1, P<0.01, Mann-Whitney test).