In the early stage, the peripheral cortex is still transparent. Therefore, in the dark, the pupils are dilated to improve vision, and in the strong light, the pupils are dilated to reduce vision, so surgery can generally be performed without waiting for the cortex to be completely turbid. Posterior posterior posterior subcapsular cataract opacity is located in the subcapsular cortex of the lens. If it is located in the visual axis area, it will affect vision at an early stage.
Clinical manifestations:
1. Cortical cataract is mainly characterized by gray opacity of lens cortex, and its development process can be divided into four stages: initial stage, immature stage, mature stage and over-mature stage.
2. The lens opacity of nuclear cataract increases from the central part of the lens, that is, the embryonic nucleus, gradually increases, and slowly spreads around. It was light yellow in the early stage, and with the increase of opacity, the color gradually deepened into dark yellow and dark brown, and the nuclear density and refractive index increased. Patients often complain of decreased presbyopia or increased myopia.
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