OPTIC CUP IN NORMAL EYE .I. CUP WIDTH, DEPTH, VESSEL DISPLACEMENT, OCULAR TENSION AND OUTFLOW FACILITY

In the normal eye, the depth of the cup and the displacement of major vessels in the cup are significantly related to the cup width and are not likely to provide different information capable of distinguishing between normal and glaucomatous cup. The cup/disc ratio is significantly and positively related to applanation pressure level and negatively related to the outflow facility (C) value of tonography. In this association applanation pressure level PA and outflow facility are not interchangeable and do not represent identical influence. Their separate effects, however, demonstrate significant interaction in which the outflow facility effect has a greater power of expression than that of PA applanation pressure level. It is hypothesized that this association reflects the sharing of common determinants of these genetically determined parameters. © 1969.