A.A. Lomonos1, A.R. Malikova2, A.N. Briko3, M.E. Stepanov4, B.A. Akselrod5

1,2,3 FSAEI HE “Bauman Moscow State Technical University” (Moscow, Russia)

1,3,4,5 Petrovsky National Research Centre of Surgery (Moscow, Russia)

3 briko@bmstu.ru

This study evaluates the applicability of the three-temperature heat-transfer model to a wearable, Peltier-based contact thermometric sensor for noninvasive forehead skin perfusion assessment.

A custom multichannel sensor was tested on a healthy volunteer through five heating–cooling cycles at a 40°C target. Passive cooling transients were highly reproducible (R2 = 0.98–0.999) and normalized curves collapsed onto a universal exponential profile ( = = 165.9 ± 37.9 s; A = 6.16 ± 0.53°C).

The reconstructed perfusion index hᵢ/hₑ ≈ 18 and parameter k > 3000 substantially exceeded reference ranges, attributed to thermal inertia of the contact assembly not captured by the first-order formulation. The relaxation time constant τ and amplitude A are proposed as more stable candidate markers of tissue thermal state, applicable to noninvasive microcirculation monitoring.

Lomonos A.A., Malikova A.R., Briko A.N., Stepanov M.E., Akselrod B.A. Experimental evaluation of a three-temperature thermometric system for transient tissue cooling analysis // Biomedical Radioelectronics. 2026. V. 29. № 6. P. 23−27. DOI: https://doi.org/10.18127/j15604136-202606-05

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