Accurate Tractography Propagation Mask using T1-Weighted Data Rather Than FA

Pamela Guevara^1,2, Delphine Duclap^1,2, Linda Marrakchi-Kacem^1,2, Denis Rivire^1,2, Yann Cointepas^1,2, Cyril Poupon^1,2, Jean-Franois Mangin^1,2

We present an improved propagation mask built from T1 data and dedicated to dMRI tractography. This mask allows a better tracking of fibers until the GM/WM interface, including the short association U-fibers. Contrary to usual FA-based masks failing at including low FA regions such as AC/PC, the fornix or crossings, this novel technique provides an accurate mask of the brain WM+GM independent of the DW data quality. Consequently, its use in conjunction with tractography techniques improves the accuracy of the anatomical connectivity of the brain by reducing false positives and increasing the detection of the subcortical connectivity.