Review Article

MRI Segmentation of the Human Brain: Challenges, Methods, and Applications

Figure 8

(a) Histogram of a bias-corrected -W MRI of an adult brain. Histograms of the tissue classes are based on manual segmentation and distributions slightly differ from the Gaussian distribution due to partial volume effect. (b) Histogram of a 1.5 T -W MRI of a neonatal brain. The difference between the neonatal and the adult brain histogram is the existence of the myelinated and nonmyelinated WM in neonates, which are separated with GM intensities. Since nonmyelinated WM is more dominant than myelinated WM, -W MRI shows inverted WM/GM intensities in neonates in comparison to adults.
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