Disparity‐induced accommodation in late‐onset myopia

The effect of disparity‐vergence on the accommodation response (AR) was measured in 10 late‐onset myopes (LOMs) and 10 emmetropic subjects during the course of a 10 minute near‐vision task (working distance 33cm). Disparity was induced by the introduction of 3 and 6Δ base‐out prisms placed before the right eye, and the resulting AR for the left eye was measured at 1 min intervals using an objective infr‐red optometer. LOMs showed a significant increase in AR with increasing disparity whereas emmetropes showed no significant differnce in AR for all disparity conditions. The implications of these findings are discussed with reference to the aetiology of late‐onset myopia.