光学离焦和形觉剥夺对幼恒河猴正视化过程的影响

Influence of Optical Defocus and Form Deprivation on the Emmetropization of Infant Rhesus Monkeys

目的:观察光学离焦和形觉剥夺对幼恒河猴正视化过程的影响。方法:将22只20～40d龄的健康幼恒河猴随机分为A(n=13)、B(n=9)两组,给A、B组动物的一眼分别配戴散射镜片(diffuser)和-3.00 D作为实验眼,所有动物另一眼均配戴0.00 D镜片作为对照。戴镜前.戴镜后2、4、6、8和12周给所有动物进行散瞳检影验光、电脑验光、角膜地形图检查、A超测量玻璃体腔长度.以动态观察在两种不同干预条件下,幼猴双眼眼球生长和屈光度的变化情况。结果:戴镜前A、B两组动物右、左眼玻璃体腔长度差异无显著性(P>0.05)。观察期内,所有猴跟玻璃体腔长度均逐渐增加,戴镜12周后.形觉剥夺组动物实验眼的玻璃体腔长度较对照眼明显变长(P<0.01),光学离焦组动物实验眼的玻璃体腔长度与对照眼相比较,虽无统计学差异(P>0.05),但从结果可以看出,实验眼玻璃体腔增长速率比对照眼快;戴镜前A、B两组动物均呈远视状态,右、左眼屈光度比较差异无显著性(P>0.05)。观察期内,所有猴眼均朝远视度数减少的方向发展,戴镜12周后,形觉剥夺组和光学离焦组动物的实验眼比对照眼呈现出明显的相对或绝对近视状态(P<0.05)。在观察过程中,所有猴眼的角膜中央区模拟角膜屈光力(Sim K值)均随时间而下降,戴镜前后,比较两组动物双眼Sim K值,均未发现有统计学差异(P>

Purpose:To investigate the influence of optical defocus and form deprivation on the emmetropization of infant rhesus monkeys. Methods: Twenty-two normal infant rhesus monkeys, between 20 and 40 days of age, were divided into 2 groups of A(n=13) and B(n=9) by random. The monkeys from group A and B wore diffuser and -3.00 D spectacle lens over their right eyes. All the animals wore 0.00 D lens over their left eyes as control. The monkeys' refractive error, corneal topography, the depth of vitreous chamber were measured at the start of lens wear and at 2, 4, 6, 8 ,12 weeks post-treatment. By these means, we can observe the changes of eye growth and refractive status dynamically. Results: Among all the animals, there was no significant difference between the right and left eyes in vitreous chamber length at the start of lens wear(P > 0.05). During the course of observation, the vitreous chamber of all the animals elongated gradually. At 12weeks post-treatment, the axial eyeball elongation of the treatment eyes of group A was more obvious than that of the control eyes(P < 0.01). As for group B, there was no apparently significant difference in vitreous chamber length between the right eyes and the left eyes at 12 weeks post-treatment (P > 0.05). But we can still find the vitreou chamber elongation of the treatment eyes was faster than that of the control eyes in this group. All the monkeys were hyperopic and there was no significant difference between their two eyes at the start of lens wear (P > 0.05). During the course of lens wear, all the eyes became less and less hyperopic. At 12 weeks post-treatment, the treatment eyes exhibited relative or absolute myopic status as compared with the fellow eyes both in group A and group B (P < 0.05). In the course of observation, the diopter of simulated keratorefraction(Sim K) value in all eyes decreased with time passing. No remarkable difference was found between the right and left eyes in Sim K value before and after lens wear in both of the two groups (P> 0.05). Conclusions: Under the condition of optical defocus and form deprivation, the treated eyes exhibited relative or absolute myopic status mainly because of the faster growth of vitreous chamber.It implies that these two methods can intervene the process of emmetropization of infant rhesus monkeys