Multidistance diffuse correlation spectroscopy for simultaneous estimation of blood flow index and optical properties

Area of Science:

• Biomedical Optics
• Medical Imaging
• Physiological Monitoring

Background:

• Diffuse correlation spectroscopy (DCS) traditionally measures microvascular blood flow.
• Accurate DCS analysis requires prior knowledge of tissue optical properties (absorption and scattering coefficients).
• DCS is often combined with diffuse optical spectroscopy (DOS) to overcome this limitation.

Purpose of the Study:

• To present a novel algorithm using multidistance DCS (MD-DCS).
• To enable simultaneous measurement of blood flow index and tissue optical properties.
• To establish MD-DCS as a stand-alone system for noninvasive microvascular blood flow assessment.

Main Methods:

• Development of an algorithm employing MD-DCS.
• Validation using noise-free and noise-added simulated data.
• Verification through phantom measurements and longitudinal in vivo mouse tumor studies.

Main Results:

• The MD-DCS algorithm successfully provides simultaneous blood flow index and optical property estimates.
• Validation demonstrated the algorithm's robustness across simulated and experimental data.
• Successful in vivo application in a mouse tumor model was shown.

Conclusions:

• MD-DCS can be used as a stand-alone system for microvascular blood flow measurement.
• This method eliminates the need for separate optical property measurements.
• MD-DCS offers a more integrated and potentially more accurate approach for noninvasive blood flow monitoring, especially at small source-detector separations (<2 cm).