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Wide-field polygon-scanning photoacoustic microscopy of oxygen saturation at 1-MHz A-line rate.

ABSTRACT: We report wide-field polygon-scanning functional OR-PAM that for the first time achieves 1-MHz A-line rate of oxygen saturation in vivo. We address two technical challenges. The first is a 1-MHz dual-wavelength pulsed laser that has sufficient pulse energy and ultrafast wavelength switching. The second is a polygon-scanning imaging probe that has a fast scanning speed, a large field of view, and great sensitivity. The OR-PAM system offers a B-scan rate of 477.5 Hz in a 12-mm range and a volumetric imaging rate of ?1 Hz over a 12 × 5 mm2 scanning area. We image microvasculature and blood oxygen saturation in a 12 × 12 mm2 scanning area in 5 s. Dynamic imaging of oxygen saturation in the mouse ear is demonstrated to monitor fast response to epinephrine injection. The new wide-field fast functional imaging ability broadens the biomedical application of OR-PAM.

SUBMITTER: Chen J

PROVIDER: S-EPMC7300162 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Wide-field polygon-scanning photoacoustic microscopy of oxygen saturation at 1-MHz A-line rate.

Chen Jiangbo J Zhang Yachao Y He Linyun L Liang Yizhi Y Wang Lidai L

Photoacoustics 20200607

We report wide-field polygon-scanning functional OR-PAM that for the first time achieves 1-MHz A-line rate of oxygen saturation in vivo. We address two technical challenges. The first is a 1-MHz dual-wavelength pulsed laser that has sufficient pulse energy and ultrafast wavelength switching. The second is a polygon-scanning imaging probe that has a fast scanning speed, a large field of view, and great sensitivity. The OR-PAM system offers a B-scan rate of 477.5 Hz in a 12-mm range and a volumetr ...[more]

PMID: 32577378

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