[Densitometric analysis of crystalline lens nucleus in the choice of strategy of surgical treatment of cataracts].

Computer analysis of TV images of the eye was used for quantitative evaluation of optic density of the lens nucleus in patients with cataracts in need of surgical treatment. Indications to cataract phacoemulsification were determined using classification of the degree of the lens nucleus maturity. This classification is based on the maximal values of optic density of the anterior third of the nucleus, obtained by the lens densitometry, coefficient of light absorption by the lens nucleus, and tentative subjective classification of the lens nucleus maturity by a color scale. In initial cataract (first degree) the mean maximal optic density of the anterior third of the nucleus is 55.8 +/- 5.7 arb. units and coefficient of the lens nucleus light absorption is 0.93, in nuclear brown cataract (fourth degree) these values are 158.7 +/- 24.4 arb units and 1.81, respectively. Cataract with brown enlarged nucleus involving the cortical layers of the lens and high optic density of these layers, with lens nucleus light absorption coefficient more than 2.5 is a contraindication to phacoemulsification.