Developmental outcome of fetal macrocephaly and associated syndromes

Macrocephaly is defined as an enlargement of the head circumference above the 98th percentile or greater than two standard deviations above the mean normalized for age and gender. The diagnosis of enlarged head circumference can be made by ultrasound, during pregnancy. This condition may be caused by enlargement of any of the head's compartments. When resulting from excessive brain tissue, the condition is defined as megalencephaly. Macrocephaly can be associated with many genetic disorders. Emphasis is placed on its outcome. Although the literature concerning macrocephaly and its neurodevelopmental features is vast, there is no general consensus concerning its outcome. Several studies claim macrocephaly is usually a benign, familial condition without any clinical significance, while others claim an association between macrocephaly and learning and attention difficulties, visuo-motor problems and expressive and receptive deficits. Based on these reports, concerning macrocephaly identified in utero, doctors find it difficult to assess prognosis and provide clear guidelines for parents.