Grüneisen Relaxation Photoacoustic Imaging

Photoacoustic imaging, merging the high contrast of optical imaging with the deep penetration of ultrasound, has become an important research tool in the biomedical field. In recent years, Grüneisen relaxation photoacoustic technology has garnered widespread attention as an emerging method for functional expansion. The Grüneisen parameter is a key physical quantity linking the thermodynamic properties of matter with the photoacoustic effect. Its high sensitivity to temperature provides a unique avenue for developing noninvasive and precise photoacoustic imaging of biological tissues. This review outlines the fundamental physical mechanisms and key technological implementations of the Grüneisen relaxation photoacoustic technique, with a focus on its innovative applications in blood flow measurement, resolution enhancement, and the specific identification of lipid components.