Pial and white matter surface reconstructions. a) Pial boundary. b) Pial boundary as wireframe surface with overlayed cortical parcellation map. c) White matter/gray matter boundary. d) Cortical thickness map derived from surfaces a) and c). The difference between the volume enclosed by the left and right pial surfaces and by the white matter/grey matter boundary surface is taken as the total cortical volume. Left and right hemisphere volumes in Table 3 are calculated as the intra-pial volumes.
Ystad et al. BMC Medical Imaging 2009 9:17 doi:10.1186/1471-2342-9-17