| Photoacoustic imaging | |
|---|---|
 Schematic illustration of photoacoustic imaging |
Photoacoustic imaging or optoacoustic imaging is a biomedical imaging modality based on the photoacoustic effect. Non-ionizing laser pulses are delivered into biological tissues and part of the energy will be absorbed and converted into heat, leading to transient thermoelastic expansion and thus wideband (i.e. MHz) ultrasonic emission. The generated ultrasonic waves are detected by ultrasonic transducers and then analyzed to produce images. It is known that optical absorption is closely associated with physiological properties, such as hemoglobin concentration and oxygen saturation.[1] As a result, the magnitude of the ultrasonic emission (i.e. photoacoustic signal), which is proportional to the local energy deposition, reveals physiologically specific optical absorption contrast. 2D or 3D images of the targeted areas can then be formed.[2]
- ^ A. Grinvald; et al. (1986). "Functional architecture of cortex revealed by optical imaging of intrinsic signals". Nature. 324 (6095): 361–364. Bibcode:1986Natur.324..361G. doi:10.1038/324361a0. PMID 3785405. S2CID 4328958.
- ^ M. Xu; L.H. Wang (2006). "Photoacoustic imaging in biomedicine" (PDF). Review of Scientific Instruments. 77 (4): 041101–041101–22. Bibcode:2006RScI...77d1101X. doi:10.1063/1.2195024.