前极性白内障在晶体的前表面呈现小的混浊。Merin氏曾提到,它们有可能是后天发生的,也可能是常染色体显性、隐性或X-性连锁遗传的。此种白内障的形成机理有三种假说:(1)胚胎发育第5周时,晶体与表皮外胚层分离不完全;(2)在前极区中引起的表皮细胞的继发改变,从而导致某个 Pre-polar cataracts show little haze on the anterior surface of the lens. Merin’s once mentioned that they may be acquired or acquired, and may be autosomal dominant, recessive or X-linked. There are three hypotheses for this mechanism of cataract formation: (1) incomplete segregation of crystals and epidermal ectoderm at embryonic development at week 5; (2) secondary changes in epidermal cells caused in the anterior polar region resulting in a certain