Human and experimental lens repair and calcification.

Lens repair and calcification have been studied in an experimental rabbit model of anterior segment necrosis. Findings were compared with those in a human senile cataractous lens with subcapsular calcification. Rabbit lenses subjected to anterior segment ischemia underwent a repair process similar to that observed in perforating lens injuries. Cellular response included the formation of fibroblast-like cells that covered epithelial defects of the anterior pole. These observations suggest that the lens epithelium can transform into fibroblast-like cells. The calcification process was a non-cell-induced, and the observed mineral was probably nucleating on organic molecules. Elemental analysis demonstrated that crystals contained calcium and phosphorus with a ratio of 2:1. The mineral was probably hydroxyapatite. Since morphological findings in rabbit lenses closely resemble those of the studied cataractous human lens, the rabbit model appears to simulate one type of lens calcification in senile cataract.