T₂ -oximetry-based cerebral venous oxygenation mapping using Fourier-transform-based velocity-selective pulse trains

Area of Science:

• Neuroimaging
• Biophysics
• Medical Physics

Background:

• Quantitative mapping of cerebral venous oxygenation fraction (Yv) is crucial for understanding brain physiology and disease.
• Existing methods for Yv mapping face challenges with signal quality and contamination.

Purpose of the Study:

• To develop and validate a T2-oximetry method using Fourier-transform-based velocity-selective (FT-VS) pulse trains for quantitative Yv mapping.
• To compare the performance of the novel FT-VS approach with traditional velocity-selective saturation (VSS)-based methods.

Main Methods:

• Developed an FT-VS based venous isolation technique using inversion pulses and velocity-selective saturation to suppress arterial and tissue signals.
• Employed a multi-echo readout for efficient venous T2 (T2,v) acquisition and cerebrospinal fluid (CSF) signal correction.
• Compared FT-VS method against VSS-based QUIXOTIC method in 6 healthy volunteers at 3 Tesla.

Main Results:

• FT-VS methods demonstrated superior venous blood signal and temporal signal-to-noise ratio (SNR) compared to VSS-based results.
• Significantly reduced cerebrospinal fluid (CSF) contamination was observed with the FT-VS approach.
• Averaged Yv values correlated well with global Yv measurements from the internal jugular vein.

Conclusions:

• The feasibility of FT-VS-based Yv estimation was successfully demonstrated in healthy volunteers.
• The enhanced venous signal and reduced CSF contamination led to good agreement between measured T2,v, Yv, and literature values.
• This FT-VS method provides a promising advancement for accurate quantitative mapping of cerebral venous oxygenation.