Diagnostic model for local temporal thermal change at the skin of the breast during extended application of diagnostic ultrasound

A biophysical model is derived to account for the temporal thermalchange at the skin of the breast as a result of ultrasound stimulationat the suspect lesion for seven minutes, with responses recordedusing an infrared camera. Twenty-two patients were studied.The observed temporal responses for malignant cases have a differentpattern from those of the benign cases studied and a mathematicalmodel is used to investigate the controlling parameters. A newmethod is used to estimate the coefficients of the resultingdifference equation which allows more useful diagnostic parametersto be computed than the corresponding continuous bioheat equation.The model is used to fit the experimental data. The resultssuggest that this method might be a rapid and noninvasive aidfor distinguishing between benign and malignant breast tumours.