Complete head cerebral sensitivity mapping for diffuse correlation spectroscopy using subject-specific magnetic...

Area of Science:

• Biomedical Optics
• Neuroimaging
• Medical Physics

Background:

• Diffuse correlation spectroscopy (DCS) is an optical technique for non-invasive bedside cerebral perfusion monitoring.
• Accurate interpretation of DCS signals requires understanding light propagation and sensitivity within the adult human head.

Purpose of the Study:

• To characterize the spatial distribution of cerebral sensitivity for DCS across the entire adult human head.
• To identify factors influencing sensitivity variations and provide guidance for optimizing probe placement.

Main Methods:

• Utilized 16 subject-specific magnetic resonance imaging (MRI)-derived head models.
• Performed Monte Carlo light propagation simulations at over 800 uniformly distributed locations on the head.
• Analyzed spatial variations in sensitivity and their correlation with anatomical features like extracerebral thickness.

Main Results:

• Identified significant and consistent spatial variations in cerebral sensitivity across subjects.
• Found that extracerebral (scalp) thickness is a primary determinant of these sensitivity differences.
• Discovered correlates of sensitivity variations suitable for real-time assessment.

Conclusions:

• Cerebral sensitivity for DCS is not uniform across the head and varies predictably with extracerebral thickness.
• Optimizing DCS probe placement based on individual head anatomy is crucial for accurate bedside cerebral perfusion monitoring.
• These findings enhance the reliability and application of DCS in clinical settings.