etiology, acuity of symptoms, need for sedation, and availability The lack of radiation exposure is a major advantage of MRI over CT Neurology and neurosurgical consultations are essential to determine further testing Any newborn with signs of increased intracranial pressure or seizures should have emergent evaluation and inpatient admission TABLE 96.1 EXAMPLES OF MACROCEPHALY IN NEONATES AND INFANTS Brain (Macroencephaly) enlargement Increased CSF production Isolated (familial megalencephaly) Nonisolated Fragile X syndrome Neurocutaneous syndromes Achondroplasia Soto syndrome Beckwith–Weidman Metabolic Leukodystrophy Lysosomal storage disease Skull bones expansion Bone marrow expansion due to chronic hemolytic anemia Skeletal dysplasia Osteogenesis imperfecta Vascular anomalies Hemorrhage Arteriovenous malformations Hydrocephalus Benign extracranial fluid Hydranencephaly Dandy–Walker malformation Choroid plexus papilloma Increased CSF pressure Meningitis Pseudotumor Lead poisoning Metabolic Mass effect Tumor Abscess Cyst Table adapted from Boom JA Macrocephaly in infants and children: Etiology and evaluation UpToDate (serial online) 2014 Available at http://www.uptodate.com/contents/macrocephaly-in-infants-and-childrenetiology-and-evaluation Updated March 13, 2014 Accessed February 27, 2015; Cohen A Disorders of head shape and size In: Fanaroff, Martin, eds Neonatal perinatal medicine 8th ed Philadelphia, PA: Mosby; 2006:998–999 Hydrocephalus