High Multiband Acceleration Degrades Resting-State Functional MRI Reliability and Signal Quality Under Anesthesia.

Area of Science:

• Neuroimaging
• Anesthesiology
• Medical Physics

Background:

• Resting-state fMRI (rs-fMRI) is crucial for mapping brain networks in anesthetized patients.
• Technical factors like anesthesia agents and acquisition parameters can influence rs-fMRI utility.
• Understanding these factors is essential for reliable neuroimaging under anesthesia.

Purpose of the Study:

• To evaluate the impact of sevoflurane, multiband acceleration, and scan duration on rs-fMRI signal quality and reliability.
• To determine the optimal parameters for high-quality rs-fMRI acquisition in anesthetized subjects.
• To assess the relationship between signal quality and reliability in clinical rs-fMRI scans.

Main Methods:

• Retrospective analysis of 64 clinical rs-fMRI scans under anesthesia.
• Assessment of signal quality using temporal signal-to-noise ratio (tSNR).
• Evaluation of within-subject reliability using split-half spatial correlations for key brain regions (M1, PCC, sgACC).

Main Results:

• Multiband acceleration significantly decreased tSNR and split-half reliability across tested brain regions.
• Sevoflurane administration showed no significant effect on tSNR or reliability.
• Increased scan duration correlated positively with improved reliability for the primary motor cortex (M1).

Conclusions:

• High multiband acceleration compromises both signal quality and reliability in anesthesia rs-fMRI.
• Sevoflurane does not appear to affect rs-fMRI quality or reliability.
• The dissociation between tSNR and reliability highlights the need for advanced quality assessment metrics.