Fiber-Based Ultra-High-Speed Diffuse Speckle Contrast Analysis System for Deep Blood Flow Sensing Using a Large SPAD...

Area of Science:

• Biomedical Optics
• Optical Imaging
• Physiological Monitoring

Background:

• Diffuse speckle contrast analysis (DSCA) is a key optical imaging method for assessing dynamic biological processes like blood flow.
• Single-photon avalanche diode (SPAD) cameras offer high sensitivity and temporal resolution, but their use in large-format arrays for DSCA is limited.
• Existing DSCA techniques face challenges in capturing rapid physiological changes with high spatiotemporal detail.

Purpose of the Study:

• To introduce and validate the use of a large-format SPAD camera for DSCA.
• To enhance the accuracy and robustness of speckle contrast measurements for biological applications.
• To demonstrate improved spatiotemporal analysis of tissue perfusion and blood flow.

Main Methods:

• Development and implementation of a novel DSCA system utilizing a large-format SPAD camera.
• Experimental validation using simulations, phantom studies, and in vivo experiments.
• Leveraging high temporal resolution and photon-detection efficiency of SPAD arrays for enhanced data acquisition.

Main Results:

• Demonstrated significant improvements in the accuracy and robustness of DSCA measurements.
• Successfully captured rapid temporal variations in blood flow over a wide field of view.
• Validated the system's capability for detailed spatiotemporal analysis of tissue perfusion.

Conclusions:

• The integration of large-format SPAD cameras represents a significant advancement for DSCA.
• This technology enhances the potential for precise monitoring of cerebral blood flow and functional tissue parameters.
• The findings pave the way for future breakthroughs in optical imaging for biomedical research and clinical applications.