Optical constants and dimensions for the myopic, hyperopic and normal rhesus eye

Complete optical constants and physical dimensions are presented for eight ametropic rhesus eyes in the range from -11.00 diopters of myopia to +8.00 diopters of hyperopia and compared with the same measurements from 40 essentially emmetropic normal control eyes. The optical constants are calculated from a Gullstrand analysis modified for the rhesus eye, and include focal lengths, cardinal points, lens power and total optical power. The physical dimensions, from keratometry and ultrasound, include corneal radius, anterior chamber depth, lens thickness, vitreous depth and axial length. A regression analysis of the data shows that refraction is strongly correlated with both axial length and vitreous depth (at the rate of 3.7 and 4.2 diopters mm-1, respectively; correlation coefficients of -0.962 and -0.821) but is essentially independent of lens power, corneal power, and total optical power. These results allow us to infer that experimentally induced ametropia in the rhesus is caused by a distortion of the globe, and is not caused by the cornea or the lens.