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Hemimegalencephaly
Hemimegalencephaly (HME), or unilateral megalencephaly, is a rare congenital disorder affecting all or a part of a cerebral hemisphere. It causes severe seizures, which are often frequent and hard to control. A minority might have seizure control with medicines, but most will need removal or disconnection of the affected hemisphere as the best chance. Uncontrolled, they often cause progressive intellectual disability and brain damage and stop development. Symptoms and signs Seizures are the main symptom. There can be as many as hundreds of seizures a day. Seizures tend to begin soon after birth, but may sometimes commence during later infancy or, rarely, during early childhood. Other symptoms * Asymmetrical or enlarged head * Developmental delay * Progressive weakness of half the body * Progressive blindness of half the body Genetics Somatic activation of '' AKT3'' causes hemispheric developmental brain malformations. Pathophysiology It is a disorder related to excessive neu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megalencephaly
Megalencephaly (or macrencephaly; abbreviated MEG) is a growth development disorder in which the brain is abnormally large. It is characterized by a brain with an average weight that is 2.5 standard deviations above the mean of the general population. Approximately 1 out of 50 children (2%) are said to have the characteristics of megalencephaly in the general population. A mutation in the PI3K-AKT pathway is believed to be the primary cause of brain proliferation and ultimately the root cause of megalencephaly. This mutation has produced a classification of brain overdevelopment that consists of two syndromes including megalencephaly-capillary malformation (MCAP) and megalencephaly-polydactyly- polymicrogyria-hydrocephalus (MPPH). Megalencephaly is usually diagnosed at birth and is confirmed with an MRI. There are several neuropsychiatric disorders linked with megalencephaly; however, studies have shown that autism is the most prevalent association with the malformation of MEG. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
