近视性离焦对静态视力和动态视力的影响

Effect of myopic defocus on static visual acuity and dynamic visual acuity

背景光学离焦对静态视力能产生明显的影响，但是对动态视力的影响尚未见报道。目的研究近视性离焦对静态视力和动态视力影响的差异及其机制。方法研究纳入40名志愿者，包括20名平均年龄（27．40±1．64）岁的成人和20名平均年龄（11．70±1．49）岁的儿童。受检眼排除眼科疾患，最佳矫正视力≥1．0D，散光≤0．75D，双眼屈光参差〈1．50D。受检眼在远用屈光全部矫正的基础上分别加戴＋1．00、＋1．50、＋2．00、＋2．50D的正透镜进行离焦，使用自制的DVA-I动态视力测试仪和静态视力表测试受试者的动态视力和静态视力。结果成人组和儿童组的静态视力和动态视力均随着离焦度的增加而下降，4种离焦度的总体差异均有统计学意义（F=506．907，P=0．000）；成人组和儿童组在各离焦度的动态视力与静态视力间的比较差异均无统计学意义（P〉0．05）；线性回归分析表明，静态视力或动态视力与离焦度间均呈阳性相关（R2=0．819，t=26．720，P=0．000；R2=0．826，t=27．420，P=0．000）；离焦度与静态视力的斜率和截距均明显陡于离焦度与动态视力的斜度和截距（F=34．180，P=0．000；F=1005．560，P=0．001）。结论等量离焦对静态视力和动态视力的影响不同，推测动态视力不仅与屈光系统有关，还可能与其他影响因素有关。

Background Researches have suggested that the defocus can induce the change of static visual acuity,but whether it produce influence on dynamic visual acuity is not clear. Objective This study was to investigate the impact of myopic defocus on static visual acuity and dynamic visual acuity and explore the essential difference between static visual acuity and dynamic visual acuity. Methods Forty volunteers were enrolled in this trial, including 20 adults with the age of 27.4±1.64 years and 20 children with the age of 11.70±1.49 years. All the eyes of subjects received regular examined to excluded the eye disease with the best corrected vision of t〉 1.0 D, astigmatism of ≤0. 75 D and anisometropia 〈 1.50 D. ＋ 1.00 D, ＋ 1.50 D, ＋2.00 D, ＋2.50 D glasses were ware respectively for the defocus on the foundation of full correction. Dynamic visual acuity was inspected by using self- made DVA- I training software, and static visual acuity was tested by static visual acuity chart （ Precision Vision, CAT. NO. 2125 ）. This clinical trial complied with the Helsinki Declaration and obtained the approval of Ethic Committee of Wenzhou Medical College. Written informed consent was received from each individual prior to the protocol. Results The dynamic and static visual acuities were gradually decreased with the elevation of defocus （F=506. 907, P = 0. 000）. No significant differences were found between static visual acuity and dynamic visual acuity in adult or children at various defocus （ P 〉 0. 05 ）. The regression linear analysis showed that a positive correlation between static visual acuity with defocus （R~ = 0. 819, t = 26.72,P = 0. 000） or dynamic visual acuity with defocus （R2 = 0. 826, t = 27.42, P = 0. 000 ）. The slope and intercept between defocus with static visual acuity were steeper than that between defocus and dynamic visual acuity （ slope ： F = 34. 18, P = 0. 000 ; intercept ： F = 1005.56, P= 0. 001 ）. Conclusion The effect of defocus on static visual acuity is different from that of dynamic visual acuity. It could be speculated that dynamic visual acuity is related not only to refractive systems but also other factor.