Agent-free High Speed Localization Photoacoustic Microscopy

Abstract

Photoacoustic microscopy ( PAM) as an emerging microscopy system have shown the capability of anatomical, functional, metabolic and pathological imaging of animals and humans in vivo. However, conventional PAM systems have limited spatial and/ or temporal resolutions. Microelectromechanical systems ( MEMS) scanners and super-resolution techniques have been used, but the MEMS scanners were unstable and conventional ultra-high resolution imaging methods were slow and/ or required exogenous contrast agents. Here, we present an agent-free high speed PAM using a stable commercial scanner ( L-PAM) that improves both spatial and temporal resolution concurrently. A B-mode image rate is improved up to a B-mode image rate of 500 Hz with the scanner. By localizing endogenous contrasts, unresolved microvessels in general PAM system are resolved. These enhancements enable the observation of microvasculatures and functional hemodynamics of animals and humans in vivo. This L-PAM enables leading to new studies in a variety of fields including neurology, oncology, pathology, pharmacology, etc.