Brown N A
Clinical Cataract Research Unit, Nuffield Laboratory of Ophthalmology, Oxford, UK.
Eye (Lond). 1993;7 ( Pt 1):63-7. doi: 10.1038/eye.1993.14.
The various effects of cataract on vision are reviewed. The morphological types of senile cataract are classified into three basic categories: cortical spoke, nuclear and posterior subcapsular (PSC). The significant basic effect of cataract on the optical system of the eye is that of light scattering. Forward light scattering (light scattered towards the retina) accounts for reduced contrast sensitivity, for glare and for reduced visual acuity. Other effects of cataract are a myopic shift, a possible astigmatism change, monocular diplopia and polyopia, colour vision shift, reduced light transmission, and field of vision reduction. The effect of the various cataract morphologies on these functions is discussed. The nature of the effect varies with the degree of the cataract and with the cataract morphology. The assessment of a patient's visual disability is therefore not a simple task and cannot be based solely on the visual acuity nor on the objective measurement of the cataract.
本文综述了白内障对视力的各种影响。老年性白内障的形态学类型可分为三个基本类别：皮质辐轮状、核性和后囊下（PSC）。白内障对眼光学系统的显著基本影响是光散射。向前光散射（朝视网膜散射的光）导致对比敏感度降低、眩光和视力下降。白内障的其他影响包括近视性移位、可能的散光变化、单眼复视和多视、色觉改变、光透射减少以及视野缩小。本文讨论了各种白内障形态对这些功能的影响。其影响的性质因白内障的程度和形态而异。因此，评估患者的视觉残疾并非易事，不能仅基于视力或白内障的客观测量。
