SPATIAL-MAPPING OF POLARIZED-LIGHT TRANSMISSION IN THE CENTRAL RABBITCORNEA

In this paper polarized light transmission measurements are made under conditions that closely approximate the physiological state in order to probe lamellar structure in the central cornea of New Zealand white rabbits. The results are interpreted with the aid of a newly develope d theory (published elsewhere) in which the cornea is modeled as stack ed birefringent layers corresponding to the lamellae. The theory enabl es predictions of the statistical properties of lamellar ordering base d on characteristics of the transmission of polarized light. The exper imental results are consistent with a structure in which a number of l amellae have a fixed azimuthal orientation (i.e, about an axis normal to the corneal surface), whereas the remainder are essentially randoml y oriented. Comparisons with the theoretical predictions are consisten t with a model in which the preferred direction in the apical region o f the cornea does not vary significantly among rabbits; and the prefer red lamellar orientation direction determined for the population measu red here is very close to that suggested in previous experiments on a smaller number of rabbits. Mapping experiments using a new goniometric holder showed that the preferential order at the apical region is clo sely preserved throughout the central similar to 4 mm diameter optical zone in individual corneas. (C) 1996 Academic Press Limited