Collecting back-reflected photons in photoacoustic microscopy

Area of Science:

• Biomedical Optics
• Microscopy
• Photoacoustic Imaging

Background:

• Optical-resolution photoacoustic microscopy typically discards back-reflected photons.
• Simultaneous multimodal imaging offers complementary information for enhanced diagnostics.

Purpose of the Study:

• To integrate a fiber-optic confocal microscope with a laser-scanning optical-resolution photoacoustic microscope.
• To achieve simultaneous multimodal imaging using a single light source.
• To demonstrate intrinsic image registration between photoacoustic and confocal microscopy.

Main Methods:

• A 2x2 single-mode fiber optical coupler was employed in a laser-scanning optical-resolution photoacoustic microscope.
• The coupler delivered illuminating laser light and collected back-reflected photons.
• This enabled the integration of confocal microscopy with photoacoustic microscopy.

Main Results:

• Simultaneous multimodal imaging was successfully achieved with a single light source.
• Images from both photoacoustic and confocal modalities were intrinsically registered.
• The capabilities were demonstrated in vivo imaging of small animals and phantoms.

Conclusions:

• The integrated system provides a powerful tool for simultaneous multimodal imaging.
• This approach enhances the information obtained from biological samples.
• The intrinsic registration simplifies data analysis and interpretation.