Necessity of correcting short distance refractive error in non-presbyopia patients

AIM: To find out the necessity and the appropriate method of correcting short distance refractive error in non-presbyopia patients by analyzing the relation between astigmatic refractive error and fixation distance.METHODS: In this prospective clinical study, 166 right eyes with myopic astigmatism were selected by sequential processing to measure at distance of 5m, 40cm and 20cm. The distance corrected near vision acuity(NCNVA)and accommodative astigmatism corrected near vision acuity(ACNVA)were measured with distance-corrected glasses and near-corrected glasses, respectively, using near vision chart. The astigmatism at near were measured under monocular condition with cross-cylinder lenses, with the tested eye looking straight ahead at the line of its best corrected vision acuity in near vision chart. The degree and axis of astigmatism between two distance of the three, DCNVA and ACNVA were compared by paired t test respectively if the data are normal distribution, if not, compared by Wilcoxon matched-pairs signed-ranks test. RESULTS: The degree of astigmatism with accommodation was increased significantly as follow order: fixating at 20cm, 40cm and distance. \〖(40cm-5m): Z=-5.316, P