Changes of ocular version with aging in normal Korean population.

The purpose of this study is to estimate normative values of maximum versions in healthy Koreans and investigate age-associated changes in eye movement, using lateral and vertical version light-reflex (LVR) test. Two hundred forty normal healthy subjects whose corrected visual acuity was better than 20/50 in both eyes, from 4 to 79 yr old (30 subjects in each decade) were studied. Maximum sustained values of dextroversion, levoversion, supraversion, and infraversion in each eye were measured using LVR test. Changes of versions according to age were analyzed. Mean normal value of dextroversion, levoversion, supraversion, and infraversion in normal Koreans was 7.7 mm, 41.6 degrees, 33.9 degrees, and 7.7 mm respectively. Contrary to values of Caucasians, levoversion (adductive movement) was more excessive and infraversion (depression) was smaller in Koreans. All versions were decreased with aging (P<0.001 for all). Levoversion had the largest decrease with aging compared with other versions (P<0.001, respectively) and infraversion had the least decrease with age than levoversion (P<0.001), supraversion (P<0.001). All maximal sustained versions were decreased with aging but the ranges of ocular movements in Koreans were different with Caucasians as version least affected and most affected by age was infraversion and levoversion in Koreans. The study standardized normal maximal versions and aging changes of versions in Koreans.