On the stability of asymmetry of thermal emission in diabetic foot disease

The purpose of the study we report is to extract radiometric information, distributed in three regions of interest (ROI’s), from the legs of patients clinically diagnosed with Diabetes Mellitus Type II (DM2) and a control group. We analyze the asymmetry of the thermal radiation emitted from the legs through two approaches: 1) comparing the higher and lower temperatures of the thermal probability distribution of each leg and 2) computing an asymmetry index based on the Spearman’s correlation coefficient; that for both groups and two views: anterior (AV) and posterior (PV). The results indicate the existence of radiometric differences between the studied groups. From the former analysis, we get that the sensitivity and specificity over the 1st, 2nd and 3rd ROI at AV are 78% and 86%, respectively. For the posterior view are 89% and 83%, respectively. Instead, by using the Spearman’s correlation coefficient, we built up an index related to the thermal asymmetry, whose (sensitivity, specificity) pair for the 1st, 2nd and 3rd ROI, (83%, 67%), (81%, 94%), and (72%, 78%), respectively.