Croft Mary Ann, Glasser Adrian, Heatley Gregg, McDonald Jared, Ebbert Timothy, Dahl David B, Nadkarni Nivedita V, Kaufman Paul L
Department of Ophthalmology and Visual Sciences, Wisconsin Regional Primate Research Center, University of Wisconsin, Madison 53792-3284, USA.
Invest Ophthalmol Vis Sci. 2006 Mar;47(3):1076-86. doi: 10.1167/iovs.04-1523.
The underlying causes of presbyopia, and the functional relationship between the ciliary muscle and lens during aging are unclear. In the current study, these relationships were studied in rhesus monkeys, whose accommodative apparatus and age-related loss of accommodation are similar to those in humans.
Centripetal ciliary body and lens equator movements were measured during accommodation in 28 eyes of 21 rhesus monkeys (ages, 5.7-26 years) by goniovideography. Ultrasound biomicroscopy was performed in 21 eyes of 17 monkeys. Narrowing of the angle between the anterior aspect of the ciliary body and the inner aspect of the cornea was used as a surrogate indicator of forward ciliary body movement during accommodation.
Average centripetal ciliary body movement in older eyes (age > or =17 years, n = 16) was approximately 20% (0.09 mm) less than in young eyes (age, 6-10 years, n = 6), but not enough to explain the 60% (0.21 mm) loss in centripetal lens movement nor the 76% (10.2 D) loss in accommodative amplitude. Average forward ciliary body movement was 67% (49 degrees ) less in older (n = 11) versus young (n = 6) eyes. Maximum accommodative amplitude correlated significantly with the amplitude of centripetal lens movement (0.02 +/- 0.003 mm/D; n = 28; P < 0.001) and with forward ciliary body movement (3.34 +/- 0.54 deg/D; n = 21; P = 0.01).
Decreased lens movement with age could be in part secondary to extralenticular age-related changes, such as loss of ciliary body forward movement. Ciliary body centripetal movement may not be the limiting component in accommodation in the older eye.
老花眼的潜在病因以及衰老过程中睫状肌与晶状体之间的功能关系尚不清楚。在本研究中，我们在恒河猴身上研究了这些关系，恒河猴的调节装置和与年龄相关的调节能力丧失与人类相似。
通过前房角录像术测量了21只恒河猴（年龄5.7 - 26岁）的28只眼睛在调节过程中睫状体向心性运动和晶状体赤道运动。对17只猴子的21只眼睛进行了超声生物显微镜检查。睫状体前表面与角膜内表面之间角度的缩小被用作调节过程中睫状体向前运动的替代指标。
老年眼（年龄≥17岁，n = 16）的平均睫状体向心性运动比年轻眼（年龄6 - 10岁，n = 6）大约少20%（0.09毫米），但不足以解释晶状体向心性运动60%（0.21毫米）的减少，也不足以解释调节幅度76%（10.2 D）的损失。老年眼（n = 11）与年轻眼（n = 6）相比，平均睫状体向前运动减少了67%（49度）。最大调节幅度与晶状体向心性运动幅度（0.02 ± 0.003毫米/屈光度；n = 28；P < 0.001）以及睫状体向前运动幅度（3.34 ± 0.54度/屈光度；n = 21；P = 0.01）显著相关。
随着年龄增长晶状体运动减少可能部分继发于晶状体外与年龄相关的变化，如睫状体向前运动丧失。睫状体向心性运动可能不是老年眼调节的限制因素。
