Detection of skin microvascular vasodilation disorders in patients with diabetic foot syndrome during the local heating test

and purpose. The aim of investigation was to evaluate the possibility of using the method of wavelet analysis of skin temperature during the local heating test for the study of the microvascular tone regulation in patients with diabetic foot syndrome (DFS). Materials and methods. The study was performed in 15 healthy subjects and 10 patients with neuro-ischemic form of DFS complicated by trophic ulcers. The temperature of the plantar surface of the hallux was recorded by «Microtest» (Perm, Russia) with temperature resolution 0,002°C. Time-frequency analysis of temperature fluctuations was performed using wavelet analysis. For the reconstruction of the oscillations in endothelial (0.02-0.0095 Hz), neurogenic (0.05-0.02 Hz) and myogenic (0.05-0.14 Hz) frequency ranges we used inverse wavelet transform. Results. In healthy people, indexes of vasodilation (relative changes in the oscillation amplitudes) in the myogenic, neurogenic, and endothelial frequency ranges were 3.04, 4.01 and 2.25 respectively. In patients with DFS the values were significantly lower than in healthy subjects (0.60, 0.67 and 0.51, respectively). Conclusion. In contrast to healthy subjects, the combination of diabetic polyneuropathy with endothelial dysfunction and macroangiopathy in patients with neuro-ischemic form of DFS leads to the progression of mutually aggravating pathological processes and lower limb ischemia. Further implementation of the local heating test at the early stages of diabetic foot is of interest for the prognosis of the disease, evaluating the effectiveness of conservative treatment and endovascular interventions.