Fast optical-resolution photoacoustic microscopy using a 2-axis water-proofing MEMS scanner

Area of Science:

• Biomedical Imaging
• Microscopy
• Optical Engineering

Background:

• Optical-resolution photoacoustic microscopy (OR-PAM) offers label-free in vivo imaging.
• Real-time imaging with high signal-to-noise ratios (SNRs) is critical for OR-PAM in disease identification.

Purpose of the Study:

• To develop a compact, fast, and water-proof scanner for OR-PAM.
• To enhance OR-PAM capabilities for real-time disease tracking and preclinical/clinical applications.

Main Methods:

• Fabrication of a 2-axis water-proofing MEMS scanner using flexible PDMS.
• Integration of the scanner into an OR-PAM system for imaging.
• Demonstration of scanning range, imaging speed, and resolution.

Main Results:

• Achieved a wide scanning range (9 × 4 mm²) and fast imaging speed (5 B-scan/sec).
• Maintained high SNRs due to in-water confocal scanning of ultrasound and laser.
• Demonstrated in vitro flow monitoring (0.14 Hz) and in vivo mouse ear microvasculature imaging.

Conclusions:

• The developed MEMS scanner enables compact, fast, and high-SNR OR-PAM.
• This technology holds significant potential for preclinical and clinical applications.
• Real-time OR-PAM imaging is advanced for disease monitoring.