Near Vision Tasks and Optical Quality of the Eye

Purpose: to study the effect of near-vision reading task on optical quality of the eye when performed on a computer monitor and on printed paper, and to identify which of the two results in greater changes. methods: two groups of subjects performed a 30-min reading task in two different conditions: on a computer monitor and on printed paper. ocular, corneal, and internal wavefront aberrations (zernike coefficients up to 6th order), root-mean-square of low- and high-order aberrations, spherical equivalent, vectoral components of ocular astigmatism ( j45 and j0), and the compensation factor between internal and corneal aberrations were measured before and after the tasks. their changes were analyzed in each group and between groups. results: statistically significant changes in wavefront aberrations and in root mean square of low- and high-order aberrations were observed in both groups which was significantly greater when the task was performed on printed paper. partial loss of compensation mechanism and variation in spherical equivalent in a negative direction occurred after both reading tasks; however, it was statistically significant only with printed paper reading task. the vectoral components of ocular astigmatism did not show statistically significant changes in either groups. conclusion: near-vision reading tasks can change the optical quality of the eye, especially when the task is performed on printed paper.