Development and reversal of calcium-induced opacities in vitro.

An investigation into the role of calcium in the opacification process has focused on the relationship between the rate of opacification and the increase in the concentration of lens calcium. A laser scanning system was designed to monitor continuously transmitted light in opaque lenses, thereby permitting a correlation between calcium concentrations and the onset and development of opacification to be obtained. Lens opacification depended both on the magnitude of the increase in the concentration of lens calcium and the time during which calcium levels were raised. Relatively small increases in the content of lens calcium over culture periods of 20 hr were as effective in producing opacities as large increases in lens calcium levels over several hours. Reversal of lens opacities also depended on the concentration of lens calcium as well as the duration over which lenses were exposed to calcium.