Extended-wear soft contact lenses for vision studies in monkeys

The authors have designed and produced extended-wear contact lenses for rhesus monkeys. High-plus lenses to correct neonatal aphakia as well as lenses dyed black for use as occluders to treat amblyopia have been evaluated. Four infant monkeys fitted with soft lenses have successfully worn these extended-wear lenses almost continuously throughout their first year of life. These experiments demonstrate that rhesus monkeys tolerate extended-wear contact lenses well when these lenses are correctly designed, comfortably fitted, and their wear carefully monitored. Furthermore, the results demonstrate that usable levels of vision can be maintained in monocularly aphakic infant monkeys. Since similar methods are now used to treat children with monocular cataracts, our animal model using extended-wear contact lenses on young monkeys should facilitate new and clinically relevant amblyopia experiments.