Functional-Morphological Studies for Aging Changes in Ocular Accommodation

观察了睫状肌和晶状体(晶状体)的形态变化与老视的关系。1)客观调节图的模式分析显示，阶梯式刺激的调节幅度大于连续刺激，35~39岁和40~44岁年龄段的调节幅度明显降低。2)晶状体厚度随着年龄的增长和调节收缩的增加而不断增加，50年代的厚度与20年代的调节收缩厚度相同。随着年龄的增长，前房深度不断减少。3)人和猴睫状肌的大小随年龄增长而减小，结缔组织比例随年龄增长而增加。两种动物的环行肌纤维的比例在人眼中增加了70岁，在猴子中增加了20岁。4)匹罗卡品的调节性收缩增加了猴眼的肌宽，使睫状肌向轴向和前向移动。5)人和猴睫状肌细胞内的脂褐素颗粒数量随年龄增加而增加。6)冷冻断裂技术显示，猕猴睫状肌细胞内的肌丝与细胞膜和核膜有直接联系。7)新生皮质纤维的相对比例增加，提示可能导致晶状体弹性随年龄增长而降低。

Morphological change of the ciliary muscle and crystalline lens(lens)were investigated in relation to the prebyopia. 1)Pattern analysis of objective accommodogram indicated larger accommodative amplitude by step stimuli than by continuous stimuli and marked decrease of the amplitude between 35 to 39 and 40 to 44 years of age by continuous stimuli. 2)The lens showed continuous increases of thickness with age and by accommodative contraction and the thickness in the fifties was as same as the accommodatively contracted lens in the twenties. The anterior chamber continuously decreased in depth with age. 3)Human and monkey ciliary muscles decreased their size and increased connective tissue ratio with age. The circular muscle fiber of both species increased their ratio by 70 years of old in the human-eye and 20 years of old in the monkey. 4)Accomodative contraction by pilocarpine caused increases of the muscle width and shifting of the ciliary muscle toward the axial-and-anterior direction of the monkey eye. 5)Lipofuscin granules in the human and monkey ciliary muscle cell showed age-dependent increase in number. 6)Freeze-fracture technique disclosed that myofilaments in the monkey ciliary muscle cell had direct connection with cell and nuclear membranes. 7)Increased relative ratio of newly formed cortical lens fibers suggested a possibility which might cause decrease of the lens elastisity with age.