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Macrocephaly in infants and children: Etiology and evaluation

Julie A Boom, MD
Section Editors
Jan E Drutz, MD
Marc C Patterson, MD, FRACP
Helen V Firth, DM, FRCP, DCH
Deputy Editor
Mary M Torchia, MD


The measurement of head circumference (also called occipitofrontal circumference [OFC]), a direct reflection of head growth, is an important step in the evaluation of childhood growth and development. Deviations from normal head growth may be the first indication of an underlying congenital, genetic, or acquired problem (eg, congenital infection, genetic syndrome, hydrocephalus, intracranial hemorrhage, storage disease, or neoplasm) [1-4]. Many genetic conditions are associated with an abnormal pattern of head growth; the earlier these conditions are detected, the earlier appropriate treatment, services, and genetic counseling can be provided [5].

The etiology and evaluation of macrocephaly in infants and children will be discussed here. The etiology and evaluation of microcephaly are discussed separately. (See "Microcephaly in infants and children: Etiology and evaluation".)


Head growth is affected by growth and alterations in the contents of the cranium (eg, brain, blood, cerebrospinal fluid [CSF], and bone) and the timing of these changes in relation to closure of the fontanelles and sutures. Changes in the volume of any component before the closure of the fontanelles and sutures may alter the occipitofrontal circumference (OFC). In contrast, changes in volume that occur after closure of the fontanelles and sutures bring about compensatory changes in the other components. (See "The pediatric physical examination: HEENT", section on 'Anterior and posterior fontanelles'.)

OFC should be measured in all children at health maintenance visits between birth and three years of age. OFC should also be measured at each visit in children of all ages with neurologic or developmental complaints. The technique for measuring head circumference (picture 1) is discussed separately. (See "The pediatric physical examination: General principles and standard measurements", section on 'Head circumference'.)

OFC measurements are most informative when plotted over time [6]. Normal head growth in infants and children and reference standards for monitoring head growth in healthy children are discussed separately. In the United States, the Centers for Disease Control and Prevention (CDC) recommend that the World Health Organization growth standards ((figure 1A-B) and (calculator 1)) be used for children age zero to two years and the CDC growth charts ((figure 2A-B) and (calculator 2)) be used for children age two to three years [7]. (See "Normal growth patterns in infants and prepubertal children", section on 'Head growth' and "The pediatric physical examination: General principles and standard measurements", section on 'Head circumference'.)

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Literature review current through: Nov 2017. | This topic last updated: Dec 08, 2017.
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