Lens Calcium and Cataract
Calcium was first implicated in the cataract process in the early years of this century when it was observed that many human cataractous lenses had very high calcium concentrations compared with clear donor lenses (Adams, 1929). The early studies had shown that not all cataractous lenses had high calcium values, and this has recently been confirmed (Duncan and Bushell, 1975). An increase in lens calcium is accompanied by white, light-scattering opacities, and these are often found in highly localized regions of the outer cortex (Duncan and Jacob, 1984). Nuclear brunescence, or nuclear cataract, appears to originate by another process, since lenses with pure nuclear cataracts have near-normal internal calcium levels. In general, it appears that sodium and calcium increase together in cortical cataract, and both ions are normally distributed in nuclear cataracts (Maraini and Mangili, 1973).
KeywordsFree Calcium Total Calcium Human Lens Nuclear Cataract Senile Cataract
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