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bioRxiv · 10.1101/2021.11.11.468253

An evaluation of resonant scanning as a high-speed imaging technique for two-photon imaging of cortical vasculature

Zhou, A.·Engelmann, S. A.·Mihelic, S. A.·Tomar, A.·Hassan, A. M.·Dunn, A. K.
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Abstract

We demonstrate a simple, low-cost two-photon microscope design with both galvo-galvo and resonant-galvo scanning capabilities. We quantify and compare the signal-to-noise ratios and imaging speeds of the galvo-galvo and resonant-galvo scanning modes when used for murine neurovascular imaging. The two scanning modes perform as expected under shot-noise limited detection and are found to achieve comparable signal-to-noise ratios. Resonant-galvo scanning is capable of reaching desired signal-to-noise ratios using less acquisition time when higher excitation power can be used. Given equal excitation power and total pixel dwell time between the two methods, galvo-galvo scanning outperforms resonant-galvo scanning in image quality when detection deviates from being shot-noise limited.

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Zhou, A., Engelmann, S. A., Mihelic, S. A., Tomar, A., Hassan, A. M., Dunn, A. K.. 2021-11-13. An evaluation of resonant scanning as a high-speed imaging technique for two-photon imaging of cortical vasculature. https://doi.org/10.1101/2021.11.11.468253

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