The pathology of this disorder shows that the cleft may be narrow or closed or wide and open. The cleft is usually located near the precentral or postcentral gyri, they can be unilateral (occurring on only one side) or zygomorphous (occurring on both sides). Multiple small convolutions in the twisted brain, or polymicrogyria, have been noted. Other malformations included or usually noted with this disorder are microcephaly (small brain),
gray emergence heterotopia (absence of binocular equilibrium in the eyes), dysplasia (abnormal tissue development) and hypoplasia (tissue underdevelopment) (Carson, 1996).
It has been deemed a cephalic disorder (by NINDS), congenital neurologic malformation (Icenogle & Kaplan, 1981), or a neuronal migration disorder (Volpe, 1995). All are accurate and essentially describe some specific characteristics of the disorder.
As in both discussion of a neurologic disorder, the discussion of its onset is polar in defining it.
There is believed to be a blast agenesis of a portion of the germinative zones and thereby the cerebral seawall that leaves the seams or clefts in this anatomical abnormality. This injury in the germinative zones is besides deemed to affect the migrating neurons-therefore the notion of neuronal migration disorder. Migrational events in the cerebrum meet in the third month of gestation.
For a better understanding, a brief discussion of ontogenesis-the summons of predetermined events occurring in comme il faut sequence to insure normal development of the CNS-is in order. dominion ontogenesis of neural tissue is a complex process that can be divided into three developmental phases: (1) embryogenesis from 0 to 1 month of gestation characterized by induction; (2) cellular...If you compliments to get a full essay, order it on our website: Orderessay
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