Abstract: In this experiment, lenses aged 50 days coming with congenital, selenium and galactal cataracts were used. After being processed with freezing-drying method,each cataractous lens was examined by the electron spin resonance to study radicals in the lens. It has been found that the intensity of radicals in congenital cataract,selenium cataract and galactal cataract was all lower than that of normal group. In congenital cataract lens,the intensity of radicals was lower than that of normal group, but higher than that of the selenium and galactal cataract. This result is also different with the results reported before. We suggest that the quality and quantity of radicals in lens change with the alternated ages.

Key words: cataract, lens, ESR