스마트폰 사용 시 자세가 시기능 변화에 미치는 영향

Purpose: This study investigated the difference in changes of visual function and recovery patterns according to posture during video watching using a smartphone. Methods: The accommodative amplitude, accommodative facility, near point of convergence, near phoria, and AC/A ratio were measured in the sitting and supine postures of 40 adults in their 20s and 30s. The changes and recovery patterns of visual function after 15 minutes of smartphone video watching and resting equivalent to that after video watching in each posture were compared. Results: The accommodative amplitude, near point of convergence, near phoria, and accommodative facility before near work in the supine posture were significantly lower than those in the sitting posture; however, there was no significant difference in AC/A ratio between the postures. After smartphone use, there was a statistically significant decrease in accommodative facility, a receding in the near point of convergence, and an exophoric shift of the near phoria in the sitting posture. After rest, accommodative facility and near phoria recovered to pre-work levels. However, only accommodative facility showed a statistically significant change after near work in the supine posture, which recovered to pre-work level after rest. Conclusions: This study showed that even with the same work, the type of visual function that changes depending on posture and the time required for recovery to pre-work levels may differ. Therefore, it is suggested that appropriate posture for each subject is necessary to minimize changes in visual function after near work and to promote significant recovery.