老年性白内障晶状体核硬度及相关因素研究

目的 检测老年性白内障晶状体核硬度并探讨其相关的因素。方法 ５０岁以上老年性白内障患者４７例（４７只眼）。术前散瞳,并按ＬＯＣＳⅡ分类,测量白内障囊外摘出晶状体核的重量、中心厚度和直径,采用测定穿透晶状体核力量的装置,测定晶状体核的硬度。多元回归分析晶状体核硬度与年龄、核颜色、病程等因素的关系。结果 切穿颜色为Ⅰ级、Ⅱ级、Ⅲ级、Ⅳ级核所需用的平均硬度与年龄、核颜色、病程等因素的关系。结果 切穿颜色

The nuclear hardness and associated factors of age-related cataract

OBJECTIVE: To determine the nuclear hardness and associated factors of age-related cataract. METHODS: Forty-seven eyes of 47 patients with age-related cataract aged > 50 years were studied. The opacity of lenses was assessed and classified by the LOCS II pre-operatively. The lens nucleus obtained during extracapsular cataract extraction (ECCE) was measured. By means of a fine conical probe and dynamometer, the resistance to penetration of different lens layers was transferred to an electric signal and recorded by a function recorder. The hardness to the penetration of different lens layers was calculated. Multivariate regression analysis was applied to the parameters including age, color of the nucleus, duration of symptoms and other factors. RESULTS: The mean force required to penetrate the lens was (0.51 +/- 0.29) Newtons (N) for grade I, (1.41 +/- 0.35) N for grade II and (1.95 +/- 0.42) N for grade III; it increased to (2.96 +/- 0.62) N for grade IV. The hardest part of the lens was located at the nucleus center. Multivariate analysis of the data showed that 85% of the variation in hardness could be explained in terms of color and opacity. The patients with myopia and diabetics had an increased incidence of grading IV nuclear sclerosis. Regression analysis revealed a positive correlation between nucleus color and weight (r = 0.4565), diameter (r = 0.5263), thickness (r = 0.5552) and hardness (r = 0.8969), P < 0.001. There was a weak positive correlation between age and the weight of nucleus (r = 0.3239, P < 0.05). CONCLUSIONS: The results indicate that the color can be used more reliably to predict physical characteristics of lens nucleus, the preoperative knowledge of which would help the surgeon in planning small-incision surgery including phacoemulsification.