Figure 1: Diffusion tensor tractography of a patient with left frontal oligodendroglioma. (a) The tumor infiltrates the left corticospinal tract (magenta) throughout its precentral gyral and centrum semiovale extents. Upper panel: Axial T1 weighted magnetic resonance imaging (MRI) sequences demonstrate left frontal oligodendroglioma. The location of the corticospinal spinal tracts (magenta) is determined by diffusion tensor tractography and superimposed on the axial T1 weighted MRI. Middle panels: Color maps demonstrate decreases in fractional anisotropy resulting from left frontal oligoglioma. Lower panels: Axial fluid attenuated inversion recovery MRI sequences indicate the location of the left frontal oligodendroglioma. Volumetric analysis determines the oligodendroglioma occupies a space of 29 cm. (b) Axial fluid attenuated inversion recovery magnetic resonance imaging sequences performed postoperatively evidence residual within the area of deep fascicular infiltration. Corticospinal tract involvement precludes safely achieving a supratotal resection and predicts worse outcomes following operative intervention. Modified with permission from Figure 1 of Castellano et al.