Muscle Architecture Measurements from DT-MRI Fiber Tracking: Tract Smoothing & Voxel Size Considerations

Bruce M. Damon^1,2

Diffusion tensor (DT)-MRI muscle fiber tracking can be used to determine muscle architectural parameters in vivo, but the data are noise-sensitive. The purpose of this study was to determine whether or not the accuracy and precision of DT-MRI-derived muscle architectural parameters could be improved by varying voxel dimensions and by fiber tract smoothing. Simulated datasets, based on previously published in vivo ultrasound images, were generated and analyzed in Matlab. Smaller voxel volumes, high signal-to-noise ratios, and 2^nd order polynomial fitting of the initially reconstructed fiber tracts were all found to be useful ways to improve DT-MRI-based muscle architectural measurements.