Photoacoustic microscopy: principles and biomedical applications


Photoacoustic microscopy (PAM) has become an increasingly popular technology for biomedical applications, providing anatomical, functional, and molecular information. In this concise review, we first introduce the basic principles and typical system designs of PAM, including optical-resolution PAM and acoustic-resolution PAM. The major imaging characteristics of PAM, i.e. spatial resolutions, penetration depth, and scanning approach are discussed in detail. Then, we introduce the major biomedical applications of PAM, including anatomical imaging across scales from cellular level to organismal level, label-free functional imaging using endogenous biomolecules, and molecular imaging using exogenous contrast agents. Lastly, we discuss the technical and engineering challenges of PAM in the translation to potential clinical impacts.

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We thank Neel Kurupassery for editing the manuscript.


This study was funded by Duke MEDx fund (to J.Y.).

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Correspondence to Junjie Yao.

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Liu, W., Yao, J. Photoacoustic microscopy: principles and biomedical applications. Biomed. Eng. Lett. 8, 203–213 (2018).

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  • Photoacoustic microscopy
  • Structural imaging
  • Functional imaging
  • Molecular imaging
  • Endogenous biomolecules
  • Exogenous contrast agents