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Updated: Jan 25, 2026
07:32
Whole-cell Currents Induced by Puff Application of GABA in Brain Slices
Published on: October 12, 2017
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Increased brain coverage and efficiency when measuring current-induced magnetic fields by use of simultaneous
Teresa Cunha1,2, Fróði Gregersen1,2, Lars G Hanson1,2
1Section for Magnetic Resonance, DTU Health Tech, Technical University of Denmark, Kgs Lyngby, Denmark.
Plos One
|January 23, 2026
Summary
Simultaneous multi-slice EPI improves Magnetic Resonance Current Density Imaging (MRCDI) for brain imaging. Optimized with specific parameters, it matches single-slice performance, enhancing brain coverage in MRCDI studies.
Area of Science:
- Biomedical Engineering
- Neuroimaging
- Medical Physics
Background:
- Magnetic Resonance Current Density Imaging (MRCDI) non-invasively validates electric field simulations in head models.
- MRCDI measures phase perturbations from weak electric currents (1-2 nT) induced by scalp electrodes.
- Low signal-to-noise ratio and susceptibility to noise are key challenges in MRCDI.
Purpose of the Study:
- To test and optimize simultaneous multi-slice (SMS) EPI for time-efficient and robust brain MRCDI.
- To assess the impact of varying multiband factors and interslice gaps on MRCDI image quality.
- To evaluate interslice signal leakage effects on measured phase in MRCDI.
Main Methods:
- Acquired MRCDI data in a phantom and five human brains using optimized SMS-EPI.
- Systematically varied multiband factors and interslice gaps, assessing image quality.
- Investigated the influence of interslice signal leakage on phase measurements.
Main Results:
- Current-free acquisitions showed noise amplification with decreased interslice distances.
- Physiological noise dominated human data, masking SMS-related penalties for gaps ≥12 mm and multiband factors 3-5.
- Phantom data showed artifacts at multiband factors 5-6, but human brain data remained artifact-free up to multiband factor 5 with sufficient interslice gaps.
Conclusions:
- Optimized SMS-EPI (multiband factor ≤5, interslice gap ≥12 mm) matches single-slice EPI performance.
- This optimization makes SMS-EPI suitable for increasing brain coverage in MRCDI.
- SMS-EPI offers a robust and time-efficient approach for brain MRCDI.
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