Resolution-matched reflection mode photoacoustic microscopy and optical coherence tomography dual modality system

Area of Science:

• Biomedical Optics
• Medical Imaging Technology
• Translational Medicine

Background:

• Photoacoustic microscopy (PAM) and optical coherence tomography (OCT) offer complementary imaging contrasts, sensitive to optical absorption and scattering, respectively.
• Integrating PAM and OCT is desirable for comprehensive biomedical imaging but often limited by resolution gaps, particularly in reflection mode systems.
• Existing dual-modality systems face challenges in achieving comparable axial resolutions between PAM and OCT.

Purpose of the Study:

• To develop a dual-modality photoacoustic microscopy and optical coherence tomography (PAM-OCT) system with matched high spatial resolution.
• To overcome the axial resolution gap typically seen in PAM-OCT systems.
• To enable advanced in vivo biomedical imaging using a reflection mode dual-modality system.

Main Methods:

• Development of a novel dual-modality system integrating PAM and OCT.
• Utilized a wide-band transparent pure-optical ultrasonic detector for enhanced performance.
• The system was designed to operate in reflection mode for improved in vivo imaging capabilities.

Main Results:

• Achieved similar high spatial resolution (micrometers laterally and axially) for both PAM and OCT components.
• Successfully demonstrated in vivo imaging of a mouse hindlimb skin, a feat not possible with transmission mode systems.
• The integrated system leverages the optical transparency of the detector for efficient reflection mode operation.

Conclusions:

• The developed PAM-OCT system effectively bridges the resolution gap between the two modalities.
• This novel reflection mode dual-modality system shows significant potential for in vivo biomedical studies requiring complementary imaging contrasts.
• The technology offers a promising advancement for preclinical research and diagnostics.