High-resolution whole-brain diffusion MRI at 7T using radiofrequency parallel transmission.

ABSTRACT:

Purpose

Investigating the utility of RF parallel transmission (pTx) for Human Connectome Project (HCP)-style whole-brain diffusion MRI (dMRI) data at 7 Tesla (7T).

Methods

Healthy subjects were scanned in pTx and single-transmit (1Tx) modes. Multiband (MB), single-spoke pTx pulses were designed to image sagittal slices. HCP-style dMRI data (i.e., 1.05-mm resolutions, MB2, b-values = 1000/2000 s/mm² , 286 images and 40-min scan) and data with higher accelerations (MB3 and MB4) were acquired with pTx.

Results

pTx significantly improved flip-angle detected signal uniformity across the brain, yielding ∼19% increase in temporal SNR (tSNR) averaged over the brain relative to 1Tx. This allowed significantly enhanced estimation of multiple fiber orientations (with

SUBMITTER: Wu X 

PROVIDER: S-EPMC6107381 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature