Adaptive Combination of Phased Array Signals for Diffusion Imaging
Benner T, van der Kouwe A, Sorensen A, Wiggins G, Jellus V, Wang R, Wedeen V
Athinoula A. Martinos Center
Diffusion-weighted MR images exhibit low SNR, especially at high spatial resolutions. Signals from phased array coils are usually combined as sum-of-squares (SoS) which is sub-optimal in low SNR conditions. We present the advantages of a reconstruction method based on matched filtering (adaptive combination, AC) for tractography. 1 mm isotropic DTI scans were done on a phantom and two subjects using both reconstruction methods. Whole brain fiber tracking was performed and the number of fibers registered for several length ranges. AC reconstruction reduces background signal intensity and leads to larger number of fibers in all but one length range.