Cerebral Cortical Morphometry from MRI

Cerebral cortical volume, cortical surface area, fronto-occipital (FO)-length, and cerebral hemisphere width were measured on coronal (transaxial) MRIs at equal Z-axis intervals (156 μm) using SliceOmatic software v4.3 (TomoVision, Montreal, Canada) as previously described [49 (link), 50 (link)]. Measurement references for FO-length and cerebral width are shown in S1 Fig. The cerebral cortex was segmented semi-automatically based on MRI contrasts and was rendered in 3D using SliceOmatic software (see Fig 1A). The 3D image was used to compute the mean cortical thickness throughout the cerebral hemisphere using Amira v5.2 (Visage Imaging, San Diego, CA, USA) as previously described [8 (link), 49 (link), 50 (link)].