Medically the evaluation by George Krucik, MD, MBA — created by Amber Erickson Gabbey — update on September 17, 2018

What is macrocephaly?

Macrocephaly describes an overly big head. It’s regularly a symptom of complications or problems in the brain.

You are watching: Head too big for body

There’s a standard provided to specify macrocephaly: The circumference of a person’s head is an ext than two standard deviations over average for your age. Or, your head is larger than the 98th percentile.

Macrocephaly is normally a symptom of various other conditions. Benign familial macrocephaly is one inherited condition. It happens in families predisposed to having actually larger heads.

Sometimes over there is a trouble with the brain, such together hydrocephalus or overabundance fluid. Underlying conditions will require treatment.

Benign extra-axial arsenal is a condition where there’s liquid in the brain. However this condition doesn’t need treatment due to the fact that the lot of fluid is minor.

Other conditions that can cause macrocephaly include:

certain hereditary syndromes and also metabolic conditionssome varieties of infections

Some youngsters will have benign macrocephaly. And they won’t suffer symptoms other than having actually a bigger head circumference.

In various other cases, youngsters may experience developmental delays, like reaching finding out milestones. Various other symptoms include:

mental disabilities or delaysrapid head growthslowed development of the rest of the human body

There are determinants that rise the likelihood that macrocephaly, prefer genetics. Familial macrocephaly is one inherited condition. It’s also thought that youngsters with autism have actually a higher incidence of macrocephaly. One study approximates 15 to 35 percent of youngsters with autism will have actually macrocephaly.

There is no evidence that macrocephaly affects children of any specific sex, nationality, or race an ext often.

A pediatrician deserve to diagnose macrocephaly. They will track an infant’s head dimensions over time. Your medical professional will additionally perform neurological tests. This can incorporate a CT scan, ultrasound, or MRI to get a better look in ~ the head and brain.

Because macrocephaly can be a symptom, you medical professional will examine your infant’s head for boost in pressure. Symptom of enhanced pressure include:


Your medical professional will also look because that bulging veins and eye problems. These symptoms require neurological evaluation to uncover the basic problem and also its severity.

Be sure to tell your medical professional if you have actually a family history of larger-than-average head size.

Treatment for macrocephaly will rely on the diagnosis.

If test don’t indicate problems, and mind scans space normal, your doctor will continue to monitor you infant’s head. Parental are additionally advised to watch for:

a bulging soft spotvomitinglack of attention in foodabnormal motions in the eyesexcessive sleepingirritability

Studies on macrocephaly in adults space limited. This is partly since head measurements are regularly only taken during a baby’s development. Macrocephaly in adult is one occipitofrontal (head) circumference increase to 3 standard deviations over the average. That can additionally be a brain weighing more than 1,800 grams. This is as result of expansion that cerebral tissue. Most adults through macrocephaly don’t proceed to thrive through adulthood.

Complications space rare in benign macrocephaly. But they deserve to occur. Human being with brain overgrowth might experience brainstem compression. This requires surgery come decompress the mind stem.

People with macrocephaly frequently have hydrocephalus. This is a problem where an abnormally high amount of cerebrospinal fluid collects in the brain.

See more: People May Not Intend To Distort Facts, But ________., Chapter 7 Memory Flashcards

Other symptom include:

seizures or epilepsyperinatal risk factorsneurologic comorbidity, or the coexistence the two problems (this have the right to lead to other complications and also health problems)

Infants through benign familial macrocephaly usually grow up with no significant complications. In other cases, the outlook for macrocephaly relies on the basic condition and also its severity.


Medically the review by George Krucik, MD, MBA — created by Amber Erickson Gabbey — to update on September 17, 2018