Optical properties of normal and coagulated tissues: measurements using combination of optoacoustic and diffuse reflectance techniques

Measurement of optical properties during coagulation can be used for monitoring of the extent of thermal injury in real time. Knowing optical properties of native and coagulated tissues one can optimize treatment parameters and provide precise coagulation of malignant and benign lesions. Attenuation coefficient and total diffuse reflectance of native and coagulated canine liver were measured with the use of optoacoustic and diffuse reflectance techniques. Absorption and reduced scattering coefficients were calculated using the obtained data. Total diffuse reflectance, absorption, reduced scattering, and attenuation coefficients of canine liver increase due to protein coagulation. The capability of optoacoustic technique to detect directly changes in attenuation coefficient can be used for monitoring of tissue coagulation in real time.