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To study diffusion-prepared neurography optimized for a large field-of-view (FOV) to include the neck and both shoulders. In a large FOV poor homogeneity of the magnetic field (B0 ) often leads to poor image quality and possibly to poor diagnostic accuracy. The aim was therefore to find an optimal (combination of) shimming method(s) for diffusion-prepared neurography in a large FOV.A 3D diffusion-prepared sequence with a large FOV was tested with and without the use of a susceptibility-matched pillow combined with image-based (IB) or standard shimming in six healthy volunteers on a 3T system. B0 , B1 , signal to noise ratio (SNR), and contrast to noise ratio (CNR) were compared between all protocols. Additionally, nerve visibility, fat suppression, artifacts, and overall image quality were ordinally (5-point scale) assessed by two readers. Furthermore, correlations between B0 and B1 (offset and variation) and SNR, CNR, and image quality were explored.The use of the susceptibility-matched pillow led to a 43% reduction of B0 variation over the brachial plexus compared to the situation without a pillow (P 0.05). The combination of the pillow with IB-shimming and the optimized diffusion-prepared sequence resulted in good nerve visibility, good fat suppression, no artifacts that would hinder clinical diagnosis, and a good overall quality (median scores ≥4). Reducing B0 variation was associated with SNR, CNR, and the above-mentioned scored features (P 0.05).The use of a susceptibility-matched pillow in combination with IB-shimming enables robust and high-quality neurography of the complete brachial plexus.

This article reviews the principle of dual-channel transmit MRI and highlights current clinical applications which are performed primarily at 3 Tesla. The main benefits of dual-channel transmit compared with single-transmit systems are the increased image contrast homogeneity and the decreased scanning time due to the more accurate local specific absorption ratio estimation, meaning that less conservative safety limits are needed. The dual-transmit approach has been particularly beneficial in body imaging applications, and is also promising in terms of cardiac, spine, and fetal imaging. Future advances in transmit SENSE, the combination of dual-channel transmit with high permittivity pads, as well as the potential increase in the number of transmit channels are also discussed.