Macrocephaly refers to an overly large head in infants. Not all cases of macrocephaly are cause for alarm. However, it is often a sign of other complications within the head or brain.
The generally used standard for macrocephaly is when the circumference, or measurement of the head, is more than 2 standard deviations above the average for that age, or larger than the 98th percentile.
Macrocephaly is not a condition in itself. It is a symptom of other conditions. Benign familial macrocephaly is an inherited condition in which a family is predisposed to having a larger head circumference.
Sometimes there is a problem with the brain, such as hydrocephalus, or excess fluid in the brain, which requires treatment.
Another condition, benign extra-axial collections, means there is a small amount of fluid in the brain, but the amount is so minor that it does not require treatment.
Other conditions that can cause macrocephaly include:
- brain tumors
- intracranial bleeding
- chronic hematomas and other lesions
- Morquio syndrome
- Hurler syndrome
- Canavan disease
A pediatrician can diagnose macrocephaly with an examination of the infant’s head measurements from birth to present. He or she will also perform a neurological test and may order specialized tests, including a CT scan, ultrasound, or MRI, to get a better look at the head and brain.
Because macrocephaly can be a symptom of problems, the doctor will evaluate the infant’s head to determine whether there is an increase in pressure. Signs of increased pressure include vomiting, irritability, and headaches. The doctor will also look for bulging veins and eye impairment. These symptoms will warrant further neurological evaluation to determine the underlying problem and its severity.
Be sure to tell your doctor of any family history of large heads.
Treatment for macrocephaly will depend on thediagnosis.
If tests indicate no problems and brain scans come back normal, the infant’s head will continue to be monitored. During the monitoring phase, parents are advised to watch for:
- a bulging soft spot
- lack of interest in food
- abnormal movements in the eyes
- excessive sleeping
Infants with benign familial macrocephaly usually grow up to live normal lives. In most other cases, the outlook for macrocephaly depends on what causes the condition.