Macrocephaly in Children

What is macrocephaly in a child?

Macrocephaly means large head size. In a child, it means when their head is measured, the results are higher than average on a standard growth chart. There are many reasons a baby or child may have a large head size. It may be due to growth of the bones of the skull. It may be due to how the brain develops. In some cases, a large brain and head size may just run in the family. This most often doesn’t cause health problems. Or a child may have a problem with bleeding, too much fluid in the brain, or an infection or growth.

What causes macrocephaly in a child?

The condition can be cause by many things, such as:

• Large head size that runs in the family (benign familial macrocephaly)

• Too much cerebrospinal fluid (CSF) in the brain (hydrocephalus)

• Bleeding in the brain or under the skull

• Infection in the brain or spinal cord

• Growths such as a tumor

• Autism spectrum disorder (ASD)

• A genetic condition that affects the shape and size of bones

• A genetic condition that affects the brain

• A problem during pregnancy that affects a baby’s brain growth

What children are at risk for macrocephaly?

A child is more at risk if he or she has a parent or sibling with macrocephaly, or a gene that causes it.

What are the signs of macrocephaly in a child?

Signs can occur a bit differently in each child. The top, back, or sides of the head may look wider or taller than that of a child their age. Their forehead may bulge out more.

The signs of macrocephaly can be like other health conditions. Make sure your child sees his or her healthcare provider for a diagnosis.

How is microcephaly diagnosed in a child?

Macrocephaly may be diagnosed before birth by prenatal ultrasound. This imaging test uses sound waves and a computer to make images of blood vessels, tissues, and organs.

After birth, the healthcare provider will give your child a physical exam. He or she will look for any other signs of problems with facial features, growths on the body, bone problems, eye problems, reflexes, or other issues. Your child will be weighed and measured. A head circumference measurement will be done. The size is compared with a growth chart.

The healthcare provider will ask you about:

• Your child’s health history, including infections and other signs or problems

• Your child’s development milestones

• The mother’s health history during pregnancy and childbirth

• Any family history of large heads

• Family history of any health disorders

Your child may have imaging tests. These are done to look at the skull, brain, and fluid in the head. These tests are painless, and may include:

• Head ultrasound (HUS). This test uses sound waves to make images of the inside of the body.

• CT scan. This test uses a series of X-rays and a computer to create images of the inside of the body. A CT scan shows more detail than a regular X-ray.

• MRI. This test uses large magnets, radio waves, and a computer to make images of the inside of the body.

Your child may have other types of tests to check for causes. These may include:

• Genetic tests. These are blood tests to look for gene changes. Some gene changes may lead to conditions that can cause a large head.

• Metabolic tests. These are blood tests to look at levels of sugar, minerals, and other substances in the blood. They show how well organs are working.

• Heart function tests. These are painless tests done with machines. They show how well the heart is working.

How is macrocephaly treated in a child?

Treatment depends on the cause. Benign familial macrocephaly doesn’t cause health problems or need treatment. Some children may need treatment to manage a disorder that causes macrocephaly. A child might have surgery to fix problems with the brain or skull. A procedure may be done to drain excess fluid. Medicine can be used to manage symptoms such as seizures.

Your child will need follow-up care to check his or her growth and development. This will include physical exams, and checking mental and movement milestones.

The healthcare team will give support and teach you how best to manage your child’s health. Over time, your child may see healthcare providers such as:

• Pediatrician or family doctor. This is a child’s primary healthcare provider.

• Neurologist. This is a healthcare provider who treats conditions of the brain, spinal cord, and nerves.

• Rehabilitation team. This includes physical, occupational, speech, and audiology therapists.

Talk with your child’s healthcare providers about the risks, benefits, and possible side effects of all treatments.

How can I prevent macrocephaly in my child?

Your healthcare provider may advise genetic counseling. You can learn more about the risk of a condition that causes macrocephaly in a future pregnancy.

How can I help my child live with macrocephaly?

The full range of issues are usually not known right after birth. Issues can be revealed as a child grows and develops. Children may need to see their healthcare team often. They will need tests to track the growth of the head. Their motor, social, intellectual, and language function will be tracked over time.

You can help your child strengthen his or her self-esteem and be as independent as possible. Your child may need physical and occupational rehabilitation. He or she may need extra support in school. The healthcare team will talk with you about the best ways to help your child.

When should I call my child's healthcare provider?

Call the healthcare provider if your child has:

• Symptoms that don’t get better, or get worse

• New symptoms

Key points about macrocephaly in children

• Macrocephaly means large head size. In a child, it means when their head is measured, the results are higher than average on a standard growth chart.

• There are many reasons a baby or child may have a large head size. It may be due to growth of the bones of the skull. It may be due to how the brain develops. In some cases, a large brain and head size may just run in the family. Or a child may have a problem with bleeding, too much fluid in the brain, or an infection or growth.

• Your child will have a physical exam, and imaging tests of the head.

• Treatment depends on the cause. It may include medicine, surgery, or a procedure.

• Children may need to see their healthcare team often. They may need tests to track the growth of the head. Their motor, social, intellectual, and language function will be tracked over time.

• Your healthcare provider may advise genetic counseling. You can learn more about the risk for macrocephaly in a future pregnancy.

Next steps

Tips to help you get the most from a visit to your child’s healthcare provider:

• Know the reason for the visit and what you want to happen.

• Before your visit, write down questions you want answered.

• At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new instructions your provider gives you for your child.

• Know why a new medicine or treatment is prescribed and how it will help your child. Also know what the side effects are.

• Ask if your child’s condition can be treated in other ways.

• Know why a test or procedure is recommended and what the results could mean.

• Know what to expect if your child does not take the medicine or have the test or procedure.

• If your child has a follow-up appointment, write down the date, time, and purpose for that visit.

• Know how you can contact your child’s provider after office hours. This is important if your child becomes ill and you have questions or need advice.