Visible CCD Camera-Guided Photoacoustic Imaging System for Precise Navigation during Functional Rat Brain Imaging

Area of Science:

• Biomedical Imaging
• Neuroscience
• Optical Physics

Background:

• Photoacoustic (PA) imaging utilizes light absorption to generate ultrasound waves for imaging.
• Preclinical brain imaging with PA systems faces challenges with positioning accuracy and user interface flexibility.
• Precise localization is critical for reproducible results in animal and clinical studies.

Purpose of the Study:

• To introduce and evaluate a novel visible charge-coupled device (CCD) camera-guided photoacoustic imaging (ViCPAI) system.
• To demonstrate the system's capability for precise positioning and real-time imaging of cerebral hemodynamics.
• To overcome the limitations of existing PA imaging systems in preclinical brain research.

Main Methods:

• Integration of an ultrasound transducer, data acquisition platform, and a CCD camera for accurate probe positioning.
• Development of a programmable MATLAB-based platform with an intuitive user interface.
• In vitro (carbon fiber) and in vivo (animal) experiments to assess positioning and imaging capabilities.

Main Results:

• The ViCPAI system demonstrated accurate localization and reproducible positioning of the ultrasound probe.
• Real-time monitoring of bilateral cerebral hemodynamic changes (CBV and SO2) during forelimb stimulation before and after induced stroke.
• Successful tracking of cortical spreading depression (CSD) progression with precise S1FL area localization.

Conclusions:

• The ViCPAI system significantly improves positioning accuracy and reproducibility in photoacoustic imaging.
• The system enables detailed investigation of cerebral hemodynamic responses in preclinical models, including stroke and CSD.
• ViCPAI offers a valuable tool for advancing preclinical and potentially clinical photoacoustic brain imaging research.