Science / Medicine : Monkeys Get Contact Lenses

Emory University researchers have fitted monkeys with contact lenses in a study that they hope will yield new ways to treat babies born with cataracts and other vision disabilities.

The study at Atlanta’s Yerkes Regional Primate Research Center involves a pediatric ophthalmologist, a primate behavioral psychologist, neuroscientists and several dozen monkeys. In the experiments, rhesus monkeys undergo lens removal surgery to simulate the operation performed on a newborn with cataracts, the cloudiness of the eye lens that often plagues older adults.

Such cataract surgery is not new. In most cases, when a lens is removed, the patient can be fitted with corrective contact lenses or glasses. But the surgery poses problems in young children because humans are born without fully developed vision systems; the eyes and the brain must learn to work together. If deprived of normal visual stimulation--such as by cataracts--special cells needed for vision fail to mature properly.

Cataract surgery must be performed in children at a very early age. Even so, doctors have had poor results in trying to stimulate development. Despite corrective lenses, the best most children have achieved has been 20-40 vision.

In the experiment, the researchers remove a healthy lens from one eye of each monkey. They fit the animals with contact lenses made at the center’s lab and try various treatments to prompt successful vision development.