The purpose of this study is to establish a new, non - invasive diagnostic technique for peripheral circulation in patients with diabetes mellitus in the early stage of arteriosclerosis obliterans (ASO) as one of the complications of diabetes mellitus. We observed peripheral circulation quantitatively by thermography and Laser- Doppler blood flowmetry. The body surface peripheral circulation in 27 patients with diabetes mellitus, including 14 males and 13 females with a mean age of 67.4 years (range from 51-82 years), and with a mean hemoglobin A1C (HbA1C) 019.5% (range from 6.8%-13.0%), and who were suffering coldness, numbness or pain in their feet, was examined using thermography and Laser- Doppler blood flowmetry. Thermographic results
were analyzed quantitatively by calculating a recovery ratio as : Recovery ratio= [Total counts of thermography (Pixels) over temperature (T) after cold -loading] + [Initial counts over T after hot-loading] Xl00 (%). Results of recovery ratios for 27 cases were 0% - 93.5%, and the average was 34.0%. At the same time, the blood flow after cold -loading was 0.91 - 5. 36ml/min/lOOg tissue and the average was 2.04ml/min/l00g tissue. We found that the recovery ratio
and the blood flow were correlated (r=O. 634, p<O. 0001). The recovery ratio for males was 28.4% and that of females was 39.9%, and there was a tendency for the recovery ratio of females to be higher than males, however, this was not statistically significant. There was a correlation between the recovery ratio and age (r=O.187, p < 0.0001), although, the correlation was low. There was also a slight correlation between the recovery ratio and HbA1C (r=0.041, p<O.OOl). On the other hand, the blood flow of males was 2. 03ml/min/lOOg tissue and that of females was 2.05. There was a tendency for the recovery ratio of females to be higher than males.
however. the correlation was not significant. There was a correlation between blood flow and age (r=O. 110, p<0 . 0001) , however, the correlation was low. There was also a
slight negative correlation between blood flow and HbA1C (r=-0.179, p<O.OOOl). The ratio of the blood flow after cold -loading at 20t divided by the blood flow after hot -loading at 36 C was 38.1 %-122%, and the average was 80.6%. There was correlation between this ratio and the recovery ratio (r=0.502, p<O.OOOl). The case of the peripheral blood flow recovered immediately to the amount of the hot-loading or
access amount of hot-loading after cold-loading, and had a high recovery ratio of thermography. This might mean that the cooled body surface was warmed by overcirculation of blood flow to keep body temperature at 30C in the mean of homeostasis. We showed that thermography and Laser- Doppler blood flowmetry were useful for non - invasive study to separate patients with poor peripheral circulation. We recommend that these methods for evaluation of further treatment, such as with Prostaglandin E1, on peripheral circulation in patients with diabetes mellitus and ASO.