[The aging of accommodative function and its pupillary response in VDT workers without subjective complaints]

Using a computer-assisted infrared optometer with a pupillometer, we measured the accommodative function and its pupillary response in 81 female subjects (age: 31-55 yrs) without visual complaints who worked via visual-display-terminal (VDT). From these measurements we analyzed the following 6 parameters regarding accommodation, and investigated whether a correlation exists between age and each parameter. The six parameters were, (1) the amplitude of objective accommodation, (2) the refractive fluctuation at the resting state of accommodation, (3) the refractive fluctuation after receiving myopic stimuli, (4) the pupil area prior to myopic stimuli, (5) the maximum rate of constriction by accommodation, and (6) the rate of pupil area recovery after accommodation. Among these parameters, the amplitude of objective accommodation, the refractive fluctuation at the resting state of accommodation, the refractive fluctuation after receiving myopic stimuli, and the pupil area prior to myopic stimuli were significantly correlated with age (all parameters: p less than 0.001). The correlation coefficients (r) were -0.810, -0.591, -0.612 and -0.320 respectively. There was also some relationship between age and the rate of pupil area recovery after accommodation (r = 0.188, p = 0.018), but no statistically significant correlation between age and the rate of constriction by accommodation (r = 0.100). These findings suggest that the overall functional capability of accommodation decreases constantly with age, though the pupillary reaction induced by accommodation is not correlated well with age.