Arnold-Chiari malformation

Just as partial failure of neural fold apposition and fusion can occur along the spine, it can also occur in the skull. Cephalic malformation can be complete in anencephalus (with little or no involvement of the lower spine) or incomplete as in encephalocele and Arnold-Chiari malformation (Figure 5). Encephalocele (Figure 5) is one such condition in which the brain extends through dura and membranous bone and comes into contact with the scalp. 

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