Fig. 3

Error types of brain image segmentation in each condition. a demonstrates the misidentification of dural and extradural structures as the grey or white matter or CSF in the superior convexity (yellow arrowhead) and the CSF image deficits in the infratentorial region (white arrowhead). The segmented CSF images are coloured light blue. b shows the misidentification of dura as the grey or white matter in the posterior cranium (red arrowhead). This type of error was observed in all conditions. c demonstrates the errors of WMH cancellation. The errors in the periventricular white matter were frequently observed in the standard condition (yellow green arrowhead). Errors in the frontal subcortical white matter were identified in both the customised and standard conditions (pink arrowhead). d shows the CSF image deficits in the superior convexity and Sylvian fissures (light blue arrowhead). The segmented CSF images are coloured light blue. The CSF image deficits in the superior convexity were observed in all conditions. CSF image deficits in the Sylvian fissures were not identified; only in the reference condition