Brain Connect. 2013 Mar 21. doi: 10.1089/brain.2012.0113. [Epub ahead of print]

Exploring Functional Connectivity Networks with Multi-Channel Brain Array Coils

Arnold Anteraper S, Whitfield-Gabrieli S, Keil B, Shannon S, Gabrieli JD, Triantafyllou C.


Using multi-channel array head coils in functional and structural MRI provides increased Signal-to-Noise Ratio (SNR), higher sensitivity and parallel imaging capabilities. However, their benefits remain to be systematically explored in the context of resting state functional connectivity MRI (fcMRI). In this study, we compare signal detectability within and between commercially available multi-channel brain coils, 32-Channel (32Ch) and a 12-Channel (12Ch) at 3T, in a high-resolution regime to accurately map resting state networks. We investigate whether the 32Ch coil can extract and map fcMRI more efficiently and robustly than the 12Ch coil using seed-based and graph-theory based analyses. Our findings demonstrate that although the 12Ch coil can be used to reveal resting state connectivity maps, the 32Ch coil provides increased detailed functional connectivity maps (using seed-based analysis) as well as increased global and local efficiency, and cost (using graph-theory analysis), in a number of widely reported resting state networks. Exploration of subcortical networks, that are scarcely reported due to limitations in spatial-resolution and coil sensitivity, also proved beneficial with 32Ch coil. Furthermore, comparisons regarding the data acquisition time required to successfully map these networks indicated that scan time can be significantly reduced by 50% when a coil with increased number of channels (i.e. 32Ch) is used. Switching to multi-channel arrays in resting state fcMRI could therefore provide both detailed functional connectivity maps and acquisition time reductions, which could further benefit imaging special subject populations, such as patients or pediatrics who have less tolerance in lengthy imaging sessions.

PMID: 23510203