Semi-automated extraction of brain contours from MRI

We compared brain volumes computed by trained operators using the BRAIN-MAP algorithm, which automatically extracts the contours of the brain from gradient-echo magnetic resonance images. The images of 19 subjects randomly selected from a group of normals and a group of patients with dementia were included. BRAIN-MAP found brain perimeters that were on the average ca. 3% tighter than those obtained by two experienced operators. Between-operator and within-operator reproducibility of the analyses were also estimated and found to be (-0.13 +/- 0.51)% and (-0.63 +/- 0.08)%, respectively. Replicate volume measurement by the computer alone provided a reproducibility of (0.44 +/- 0.46)%.