不同年龄健康人眼调节状态超声生物显微镜对比观察

目的 了解健康人眼在不同调节状态下,睫状体、晶状体形态位置动态变化的特点及其与年龄变化的关系.方法 利用超声生物显微镜(UBM),对70名不同年龄组正常人眼注视远、近不同距离视标时睫状体、晶状体形态位置的变化进行动态观察和统计学分析.结果 (1)视远时,睫状体厚度平均值(1.08±0.15)mm,睫状突长度平均值(1.92±0.29)mm, 睫状突宽度平均值(0.74±0.11)mm,晶状体中央厚度平均值(3.46±0.45)mm;视近时,睫状体厚度平均值(1.16±0.17)mm,睫状突长度平均值(2.05±0.27)mm,睫状突宽度平均值(0.67±0.09)mm,晶状体中央厚度平均值(3.57±0.42)mm;视近与视远相比,睫状体前部厚度增加、睫状突长度增加,睫状突宽度变小,晶状体中央厚度增加,各参数经独立样本t检验,P值均<0.05,差异有统计学意义.(2)随年龄增加,视远、视近时各形态参数与年龄间经Pearson检验存在相关性.结论 人眼视近时,睫状体各部肌纤维协调收缩,使睫状突变长变尖,睫状体向前向内移动,松弛悬韧带,晶状体借自身弹性变凸,中央厚度变厚,前后径增加.同时,随年龄增长,人眼调节力逐渐下降.支持Helmholtz的调节松弛学说.利用UBM可实时观察人眼调节时眼前节结构形态和位置的变化情况.

Comparative analysis of the normal eyes accommodative conditions in different age groups

Objective To study the changes of the configuration and the position of ciliary body and lens response of normal human eyes with advancing age under different accommodative conditions.Methods The configuration and position in ciliary body and lens of 70 normal human eyes under different ages groups were observed real-timely and measured by ultrasound biomicroscopy(UBM),when these eyes focused on given far and near optotypes respectively.All of these parameters between far and near accommodations were compared by statistic analysis.Results (1)In near accommodation,there were statistically significant increase in the thickness of anterior ciliary body,length of ciliary process and central lens depth.There were statistically significant decreases in width of ciliary process.(2)Decreased accommodation of human with ages.(3)Parameters of configuration had close correlation with each other,and it was also true in those of position.Conclusions In the process of near accommodation,ciliary body shifts forwards and inwards,ciliary process becomes tapered because the harmonious contraction of its circular and meridional muscle fibers,meanwhile decreased accommodation of human with ages.This is consistent with the classical relaxation mechanism of accommodation described by Helmholtz.UBM is a new noninvasive method for real-time studying of the ciliary body changes in far-near accommodating human eyes in vivo.