Analysis of Characteristic Eye Movement Behaviors of Young Adults with Different Degrees of Myopia

  Objective  To measure the parameters of eye movement of young adult patients of myopia, to compare the differences in the parameters of patient groups with varied degrees of myopia, and to analyze the correlation between eye movement parameters and axial length (AL) and spherical equivalent refraction (SER).

  Methods  A total of 91 young adult patients of myopia were recruited. The subjects were divided into three groups of low, moderate, and high myopia according to their SER. Information on the subjects’ age and sex was collected and general clinical examination was completed. The subjects’ binocular fixation, reflexive saccade, and antisaccade were measured with eye tracker. One-way ANOVA or Kruskal-wallis test was used to compare the general data and eye movement parameters of the three groups of myopic patients. Pearson or Spearman correlation analysis was used to analyze AL and SER’s correlation with 95% bivariate contour ellipse area (BCEA) and saccadic parameters.

  Results  The 95% BCEA for mild, moderate, and high myopia groups were 2.08 (0.54, 14.69) deg², 4.99 (0.94, 49.22) deg², and 5.79 (2.18, 64.91) deg², respectively. There was significant difference between the 95% BCEA of the three groups (P=0.029). The 95% BCEA of the mild myopia group was significantly smaller than that of the high myopia group (P=0.01). There were no significant differences in saccadic parameters among the three groups (P>0.05). There was a significant positive correlation between 95% BCEA and AL (r=0.342, P=0.001). There was a significant negative correlation between 95% BCEA and SER (r=−0.322, P=0.002). There was no significant correlation between the parameters of saccadic movement and the AL or SER (P>0.05).

  Conclusion  For young adult myopic patients, the longer the AL is, the higher the degree of the myopia and the worse the fixation stability becomes. The fixation stability of patients with high myopia was significantly worse than that of patients with mild myopia. There was no significant difference in saccadic parameters in patients with different degrees of myopia.