Birefringence of the cat cornea

Birefringence measurements for freshly enucleated cat eyes were conducted by the scattered light method and the oblique incidence method. Average birefringence of β = 0·0017 for the central region was obtained. Birefringence was greatest at the anterior surface of the cornea and decreased gradually toward the posterior surface. A multitude of highly localized zones of grossly different birefringence values was revealed. In addition random macroscopic variations of birefringence were observed within the central region. The change of birefringence with intraocular pressure for a pressure increment from 10 to 40 mmHg, did not exceed 3%.