To test whether subjects with diabetes mellitus (DM) have enhanced retinal flavoprotein autofluorescence compared with age-matched control subjects using a rapid, noninvasive clinical imaging method.
Twenty-one subjects with DM and 21 healthy age-matched control volunteers were subjected to retinal imaging using 1-ms flashes of 467-nm light. Flavoprotein autofluorescence for each flash at 535 nm was recorded using an electron-multiplying charged-coupled device camera with a 512×512-pixel chip. The average intensity and the average curve width of retinal flavoprotein autofluorescence were determined by analyzing histograms of pixel intensities plotted for each eye.
When stratified by age, the mean average intensity and average curve width levels in subjects with DM were significantly greater than those in controls across all 3 consecutive decades of life studied (P ≤ .004 and P ≤ .006, respectively). An overall comparison of the mean average intensity and average curve width levels in all subjects with DM vs all controls, with adjustment for age, was consistent with the results found in each age category (P =.001 and P < .001, respectively). Subjects having DM with retinopathy in at least 1 eye had significantly greater average intensity and average curve width than subjects having DM without retinopathy in either eye (P =.002 and P =.005, respectively).
Flavoprotein autofluorescence measurements may be clinically useful to rapidly and noninvasively identify diabetic metabolic tissue stress and disease severity. Development of flavoprotein autofluorescence technology is likely to result in a tool that will improve DM screening and disease management.