pediatrics
Malformed Cerebral Hemispheres
Introduction
Cerebral hemispheres may be large, small, or asymmetric; the gyri may be absent, unusually large, or multiple and small. In addition to the grossly visible malformations, microscopic sections of normal-appearing brain may show disorganization of the normal laminar neuronal arrangement. Localized deposits of gray matter may be present in regions normally occupied only by white matter (heterotopic gray matter). Malformations of the cerebral hemispheres may be due to genetic or acquired causes. Acquired causes include infections (eg, cytomegalovirus) and vascular events that interrupt the blood supply to the developing brain. Microcephaly or Before birth, diagnosis is by prenatal ultrasonography, MRI, or both. However, a significant proportion of subtle malformations can be missed by prenatal imaging. After birth, diagnosis is based on presence of associated symptoms described above. Treatment is supportive, including antiseizure medications, specialized education, and, if needed, therapy. 