Figure 3.
T1-weighted midsagittal MRI and diffusion tensor imaging tractography of two patients with partial ACC (pACC) and a normal corpus callosum control. (A, C and F) T1-weighted midsagittal MRI scans. (B, D and G) High-angular-resolution diffusion imaging. Arrows indicate callosal fragments present in partial patients with ACC. (E and H) Q-ball tractography of partial patients with ACC reveals callosal connections between homotopic and heterotopic cortical regions. Homotopic connections between anterior frontal lobes are conserved in both partial patients with ACC (blue streamlines in E and H; orange streamlines in H), but the degree of temporal and occipital connectivity varies. Both patients also show ‘sigmoid bundles’ (yellow streamlines in E and H), which connect the anterior frontal lobe with the contralateral parieto-occipital region. Images adapted from Wahl et al. (2009).