Measurement of photoacoustic signals from skin: Potential application to burn depth estimation

We propose a new method of bum depth estimation based on the measurement of photoacoustic signal from the skin, where the acoustic waves originated from the light absorption by blood are detected with a piezoelectric transducer put on the skin surface. Because vascular occlusion takes place in the thermally-damaged tissue layer, the propagating time of the bloodoriginated signals would have the depth information of injury. To investigate the validity of the proposed diagnosis, experiment using rat bum model was performed. The results showed that deep bum (DB), deep dermal bum (DDB), and control (healthy skin) can be well differentiated by the photoacoustic signals. Quantitative information relating to the depth of injury can be also obtained from the signals.