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Stephen J. Falchek

, MD, Nemours/Alfred I. duPont Hospital for Children

Last full review/revision Apr 2019

Macrocephaly is the technical term for a large head.

  • Macrocephaly can be normal or caused by genetic disorders or other disorders.

  • Diagnosis is made before birth through routine ultrasound tests or after birth by measuring the head circumference.

  • Doctors usually do imaging tests to look for brain abnormalities and sometimes blood tests to look for a cause.

  • Treatment for macrocephaly depends on the cause, and sometimes, if no problems are found, no treatment is necessary.

Macrocephaly can be classified as

  • Disproportionate: The head is larger than appropriate for the child's overall size.

  • Proportionate: The head appears appropriately sized for the body (in other words, the child has a large body and a large head).

Many people with large heads or large skulls are healthy.

Abnormal macrocephaly may be due to an enlarged brain (megalencephaly), water on the brain (hydrocephalus Hydrocephalus Hydrocephalus is an accumulation of extra fluid in the normal spaces within the brain (ventricles) and/or between the inner and middle layers of tissues that cover the brain (the subarachnoid... read more Hydrocephalus ), overgrowth of the bones of the skull (cranial hyperostosis), or other conditions. These conditions may be the result of genetic disorders or disorders the child acquired before or after birth.

Diagnosis of Macrocephaly

  • Before birth, ultrasound

  • After birth, physical examination, including measurement of head circumference and sometimes imaging tests and blood tests

After birth, doctors measure a baby's head circumference Head Circumference Physical growth refers to an increase in body size (length or height and weight) and in the size of organs. From birth to about age 1 or 2 years, children grow rapidly. After this rapid infant... read more (the measurement of the head around its largest area) during routine physical examinations. They diagnose macrocephaly when the head circumference is significantly larger than the normal range for babies of the same sex, age, and ethnic group in the region where the baby lives. When making the diagnosis, doctors also take into account the head circumference of the baby's parents and grandparents because a slightly larger head size may run in the family.

Treatment of Macrocephaly

  • Depends on the cause

Treatment of macrocephaly depends on the cause. Sometimes, no treatment is necessary. If the cause is an abnormality, such as hydrocephalus, treatment, including surgery, may be necessary.

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Preventive Health Care Visits in Infants
Frequent doctor visits are recommended for all infants younger than 1 year of age. These visits, also called well-child visits, make it possible to check development, look for health problems, provide age-appropriate vaccinations, and educate parents. Which of the following is a condition that might affect some infants born very prematurely, with less than 32 weeks of development in the uterus?
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