Thermal Diffusion
The BPM technology measures perfusion by tracking changes in power required to heat a small volume of tissue to a fixed temperature as blood moves past the heated tip. The figures to the right outline the method.
When the probe is powered on, a thermal field develops around the heated tip which grows with time until it is fully developed. The fully developed thermal field defines the interrogation volume over which perfusion is quantified. It takes approximately four minutes for the thermal field to fully develop following power-up and enable an accurate measurement of perfusion.