Isometric multimodal photoacoustic microscopy based on optically transparent micro-ring ultrasonic detection

Area of Science:

• Biomedical Imaging
• Optical Microscopy
• Photoacoustic Microscopy

Background:

• Photoacoustic microscopy (PAM) offers molecular specificity complementary to optical microscopy.
• Optical resolution photoacoustic microscopy (ORPAM) has high lateral resolution but limited axial resolution.
• Current ORPAM techniques lack isometric spatial resolution and are often complex for high-speed imaging.

Purpose of the Study:

• To develop an isometric optical resolution photoacoustic microscopy (ORPAM) system.
• To achieve uniform spatial resolution in both axial and lateral directions.
• To enable simultaneous multi-contrast imaging (fluorescence and absorption) of single cells.

Main Methods:

• Utilized an optically transparent micro-ring resonator ultrasonic detector.
• Integrated the detector with a commercial inverted microscope platform.
• Developed a novel ORPAM system achieving isometric spatial resolution.

Main Results:

• Achieved isometric spatial resolution in ORPAM for the first time.
• Demonstrated simultaneous single-cell imaging using extrinsic fluorescence, intrinsic autofluorescence, and optical absorption contrast.
• The system is easily integrated with established optical microscopic modalities.

Conclusions:

• The developed isometric ORPAM system overcomes previous resolution limitations.
• This technique allows for versatile, multi-modal single-cell imaging.
• The improved accessibility of this ORPAM system promises wider adoption by biomedical researchers.