Abstract
SummaryThis study introduces an improved computing scheme for determining eye rotation from Purkinje images I and IV. The original computing scheme systematically underestimated eye rotation. Paraxial raytracing calculations revealed that this error resulted from failure to account for the fact that Purkinje images I and IV fall al different distances behind the cornea. The error could be overcome with a correction factor derived from paraxial raytracing calculations. A series of experiments were carried out to test the validity of this correction factor; involving exact raytracing calculations as well as measurements on physical model eyes and human eyes. The influence on the correction factor of ocular surface asphericity, accommodation, age and ocular component variations were examined. The new method was also compared to Hirschberg's technique, which makes use of Purkinje image I alone, as a means of screening for strabismus.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call