A 3T MRS Sequence for Quantification of Glutathione in Human Brain Using Stepwise Filtering

Area of Science:

• Neuroimaging
• Magnetic Resonance Spectroscopy
• Biochemistry

Background:

• In vivo brain glutathione (GSH) quantification is challenging due to significant spectral overlap in conventional ¹H MRS.
• Existing methods struggle to simultaneously isolate GSH signals and eliminate interfering signals.

Purpose of the Study:

• To develop a novel StepWIse FilTering Point-Resolved Spectroscopy (SWIFT-PRESS) sequence to overcome spectral overlap limitations in brain GSH quantification.
• To enable specific, stable, and quantitative in vivo detection of brain GSH.

Main Methods:

• Developed SWIFT-PRESS by transposing stepwise filtering from signal processing to quantum spin dynamics.
• Utilized a cascaded architecture of customized filter modules to circumvent single-pass filter limitations.
• Benchmarked SWIFT-PRESS against conventional PRESS and MEGA-PRESS sequences.

Main Results:

• SWIFT-PRESS successfully eliminated creatine interference with ~70% GSH retention.
• Demonstrated high selectivity and robustness in vivo in the parietal lobe and basal ganglia.
• Achieved precise mean GSH concentrations (2.45 mM parietal, 2.88 mM basal ganglia) and revealed inhomogeneous GSH distribution in the basal ganglia.

Conclusions:

• SWIFT-PRESS overcomes conventional spectral editing limitations for specific, stable, and quantitative in vivo brain GSH detection.
• The technique provides insights into micro-regional metabolic heterogeneity.
• Establishes a foundation for advanced clinical investigations of oxidative stress-related disorders.