A note on the mapping and quantification of the human brain corticospinal tract.

Several diffusion tensor imaging tractography (DTT) have been adopted to construct the living human brain corticospinal tract. In this Note, we applied method "A" as recently described and used by "Lin CC, Tsai MY, Lo YC, et al. Reproducibility of corticospinal diffusion tensor tractography innormal subjects and hemiparetic stroke patients. Eur J Radiol 2013;82: e610-6." We compared the results obtained with method "A" with those obtained using an anatomy-guided method "B" on two healthy adults. We also quantified the results using tract volume, and corresponding fractional anisotropy, mean, and radial diffusivities. We demonstrate that accurate mapping and quantification of CST requires at least two regions of interest one at the level of the medulla oblongata, a second at the level of pons, this assures termination at the motor spine and contamination with cerebellar and sensory pathways.