Effect of Interrupted Lens Wear on Compensation for a Minus Lens in Tree Shrews

Abstract

The eyes of tree shrews can tolerate altered monocular visual stimulation produced by a minus lens worn for 12 h of a 14-h light cycle without developing an induced myopia. However, when the lens is worn more than 12 of 14 h each day, compensation appears to increase linearly with decreased lens-off time. If the eyes of human children respond similarly to defocus from near work or other sources, it would seem that the defocus must be present almost all the time to induce myopia. If defocus contributes to human myopia through a compensation mechanism, then an increase in the amount of time that focused images are present should reduce myopic progression.