Abstract
Purpose:
To compare the accommodation and pupil reaction using the accommodative and light stimulus in dynamic characteristics.
Methods:
Seventeen volunteers (3 male and 14 female; mean age 22.3 ± 2.4 yrs, ranging from 20 to 31 yrs) participated in this study. All subject had a visual acuity 20/20 or better and normal ocular health. Accommodative and pupil reaction were measured using WMT-1 (SHIGIYA MACHINERY WORKS, Ltd) combined with a binocular open autorefkeratometer (WAM5500) and target moving system. The moving method was used square drive of visual stimulus stepwise from 1.0 (1D) to 0.2 meters (5D). Accommodative stimulus was used the shape of the asterisk (target brightness: approximately 35 cd/m2), ORT-Y (NEITZ INSTRUMENTS CO, Ltd), which is a kind of penlight as light stimulus (target brightness: approximately 4200 cd/m2) was also used. In addition, to reduce brightness of light stimulus, we used neutral density filters (transmittance; 50, 10, 4 and 2 %). Accommodative and pupil reaction were continuously measured accompanying the target moving. We compared the quantity of accommodative response, and constriction rate between accommodative and light stimulus.
Results:
In accommodative stimulus, accommodative response (4.56 ± 0.46 D) is larger than light stimulus (4.31 ± 0.39)(p < 0.01, ANOVA, Scheffé test). On the other hand, the constriction rate light stimulus (28.5 ± 4.8 %) is larger than accommodative stimulus (11.3 ± 7.5 %) (p < 0.01, ANOVA, Scheffé test). Due to neutral density filter wearing, constriction rate decreased and accommodative response increased. There was no statistically difference between both refractive responses at 1 m stimulus (p = 0.61).
Conclusions:
The pupil constriction in light stimulus causes to decrease accommodative response.
Keywords: 404 accommodation •
667 pupil •
676 refraction