Dynamic Measurement of Accommodation and Pupils Size Under Different Lighting Condition

Abstract

Purpose : This study investigated the dynamic measurement of accommodation response and pupil size change by different lighting conditions and its effect on visual function. Methods : Seventeen (23.06±0.51) students participated who had no history of ocular surgery. All participants had normal binocular vision and more than 0.8 visual acuity. Dynamic accommodation and pupil size were measured using open-type auto-refractor(WAM-5500) with 5 Hz frequency under three lighting conditions (photopic vision, mesopic vision, and scotopic vision). Accommodation stimulus in the distance of 40 cm, 40~30 cm, 30 cm, 30~20 cm, and 20 cm were induced for 5 seconds. In addition, the visual function such as VA and contrast sensitivity were measured. Results : The accommodation response was the highest in photopic vision and the lowest in scotopic vision(p＜0.050). The change of pupil size was measured to be the smallest under photopic vision and the largest under scotopic vision(p＜0.050). The visual acuity and contrast sensitivity also showed the highest value in photopic vision and the lowest value in scotopic vision(p＜0.050). Conclusion : This study demonstrated the dynamic changes of accommodation and pupil size under different lighting conditions. Under low lighting condition, accommodative response were less than accommodative stimulus and visual function deteriorated accordingly. It showed continuous changes of accommodation under static condition, therefore several measurement of accommodation or visual function may be recommend.