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What is Microcephaly is defined as head circumference _________ and explain in detail?
*Microcephaly is defined as an occipitofrontal circumference more than 3 standard detions (SD) below the mean for given age, sex and gestation. *Causes are structural brain malformations, inherited syndromes, congenital or acquired infections, hypoxic ischemic insults and rarely metabolic disorders. Isolated inherited microcephaly is autosomal recessive. Reference : page 36 Ghai Essential Pediatrics 9 th edition