Wavelet transform analysis of skin perfusion during thermal stimulation

This work elucidates the mechanisms of skin microcirculation response to local heating at 44\ub0C in vasculopathic patients. Laser Doppler and tcpO2 were simultaneously acquired. Patients were selected on the basis of tcpO2: Group\ua0A 50\u200ammHg. The wavelet analysis of signal oscillations displays six frequency intervals. Each interval is assigned to a specific cardiovascular activity. The contributions of cardiac, myogenic and neurogenic activities were selectively detect. Thermal stimulation increased relative amplitude in all patients: heart activity by +103.26% in A, +162.84% in B, +454.54% in C; myogenic activity by +52.45% in A, +38.51% in B, +156.19% in C; the neurogenic activity +43.36% in A, +74.15% in B, +242.42% in C. Thermal stimulation increased relative power in all patients: heart activity by +365.30% in A, +473.72% in B, +1393.77% in C; myogenic activity by +106.92% in A, +66.03% in B, +380.18% in C; the neurogenic activity by +77.00% in A, +162.65% in B, +771.93% in C.This work demonstrates that the spectral analysis allows extracting from Laser Doppler signals more information than that can be gained by solely investigating perfusion values over time