Hyperaemia assessment in clinical diathermy: a microcirculation model

A microcirculation model is developed to describe the hyperaemic effects of local diathermic therapy. The model is based on a simple network of vessels constituting a Vascular Functional Unit (VFU) which is considered the 'base element' of the microcirculation system. The theoretical analysis developed in this paper allows to quantitatively describe the relationships among blood flow, volume and velocity during tissue heating. The results obtained by the VFU model point out the relative importance of the different mechanisms for local blood control during and after clinical diathermy, also suggesting the range of applicability of the different physical techniques for the detection of heat induced changes in the microcirculation.