Autofluorescence in cataractous human lens and its relationship to light scatter

The autofluorescence profile of the lens was measured from 84 eyes of 84 patients with cortical, nuclear, posterior subcapsular, or mixed lens opacities. Measurements were performed with a fluorometer in the blue-green autofluorescence range (495 nm/520 nm). The mean maximum autofluorescence value differed in every cataract group statistically significantly from that of the age matched controls (p < or = 0.0058). The highest autofluorescence values were measured in nuclear and mixed cataract groups (p < 0.0001) with high and narrow autofluorescence profile. In cortical cataracts the curve was low and flattened and the mean maximum autofluorescence value was lower than in the control eyes (p < 0.0001). The maximum autofluorescence was related to lens coloration as well as to visual acuity only in nuclear cataract. The regression between maximum autofluorescence and light scatter was statistically significant only in the nuclear cataract group (p = 0.0004). Since the autofluorescence profiles differed not only in height but also in width between the cataract groups, various width/maximum autofluorescence ratios were measured. In nuclear and mixed cataract groups the ratio 75% width/maximum autofluorescence was statistically significantly lower than in other groups (p < 0.0001). In cortical cataracts the ratio (50% width - 75% width)/maximum autofluorescence was statistically significantly higher than in other groups (p < 0.0001).