A novel coil array for combined TMS/fMRI experiments at 3 T

Area of Science:

• Neuroimaging
• Biomedical Engineering

Background:

• Concurrent transcranial magnetic stimulation (TMS) and functional magnetic resonance imaging (fMRI) are powerful tools for studying brain function.
• Current TMS/fMRI setups using birdcage coils have limitations in sensitivity, positioning, and imaging techniques.
• These limitations hinder the full potential of combined TMS/fMRI for precise brain stimulation and imaging.

Purpose of the Study:

• To develop and evaluate a novel ultraslim 7-channel receive-only coil array for 3 Tesla (3T) MRI.
• To overcome the limitations of conventional setups in concurrent TMS/fMRI studies.
• To improve signal-to-noise ratio and enable advanced imaging techniques in combined TMS/fMRI.

Main Methods:

• An ultraslim 7-channel receive-only coil array was designed for 3T MRI.
• The coil array was positioned between the subject's head and the TMS coil.
• Interactions between TMS and the new coil array were investigated, and performance was compared to standard setups.

Main Results:

• A five-fold increase in MR sensitivity was achieved at the depth of TMS stimulation.
• Parallel imaging with an acceleration factor of two was feasible with low g-factors.
• Interactions between TMS and the novel coil array were found to be negligible.

Conclusions:

• The novel coil array is safe for concurrent TMS/fMRI experiments.
• It significantly improves signal-to-noise ratio and enables parallel imaging.
• The ultraslim design allows flexible TMS positioning for efficient brain stimulation and imaging.