fMRI Finger Representations in the Primary Somatosensory Cortex at 3T – Parallel Imaging vs. Partial Fourier Techniques for the EPI Sequence

Motivation: fMRI is usually applied with either parallel imaging (PAT2) or partial Fourier (pFOU), but there is no systematic comparison between both techniques. Goal(s): Mapping of the somatotopic representation of each finger as a demanding task was selected to address the advantages and disadvantages of both techniques and to further optimize it for clinical application. Approach: PAT2 and pFOU were compared for fMRI of the sensorimortor cortex in 5 healthy volunteers with independent tactile stimulation of each fingertip. Results: Both techniques revealed comparable results for somatopy, but PAT2 allowed a larger number of slices; 200 instead of 300 measurement seem to be sufficient. Impact: fMRI with parallel imaging instead of partial Fourier, a voxel size of (1.5mm)3 and 200 measurements seems to be a reliable technique at 3T for mapping finger representations in somatosensory cortex, which is also well suited for application in patients.