Craniosynostosis

There are various types of craniosynostosis depending on how many bones are fused together. 

• Sagittal synostosis: The sagittal suture runs along the top of the head, from the baby’s soft spot near the front of the head to the back of the head. When this suture closes too early, the baby’s head will grow long and narrow (scaphocephaly). It is the most common type of craniosynostosis.
• Coronal synostosis: The right and left coronal sutures run from each ear to the sagittal suture at the top of the head. When one of these sutures closes too early, the baby may have a flattened forehead on the side of the skull that closed early (anterior plagiocephaly). The baby’s eye socket on that side might also be raised up and his or her nose could be pulled toward that side. This is the second most common type of craniosynostosis.
• Lambdoid synostosis: The lambdoid suture runs along the backside of the head. If this suture closes too early, the baby’s head may be flattened on the back side (posterior plagiocephaly). This is one of the rarest types of craniosynostosis.
• Metopic synostosis: The metopic suture runs from the baby’s nose to the sagittal suture at the top of the head. If this suture closes too early, the top of the baby’s head shape may look triangular, meaning narrow in the front and broad in the back (trigonocephaly). This is one of the rarest types of craniosynostosis.

Craniosynostosis can be caused by a genetic error, metabolic disease or an overactive thyroid. Surgery can help relieve pressure on the brain and nerves and reshape the skull. Some children can use a mold that helps shape the skull and lets the brain grow.

Many of the problems a baby can have depend on:

• Which sutures closed early
• When the sutures closed (was it before or after birth and at what age)
• Whether or not the brain has room to grow

Sometimes, if the condition is not treated, the buildup of pressure in the baby’s skull can lead to problems, such as blindness, seizures or brain damage. Recent findings from studies about some factors that increase the chance of having a baby with craniosynostosis:

• Maternal thyroid disease: Women with thyroid disease or who are treated for thyroid disease while they are pregnant have a higher chance of having an infant with craniosynostosis, compared to women who don’t have thyroid disease.
• Certain medications: Women who report using clomiphene citrate (a fertility medication) just before or early in pregnancy are more likely to have a baby with craniosynostosis, compared to women who didn’t take this medicine.

Recently, CDC reported on important findings from research studies about some factors that increase the chance of having a baby with craniosynostosis:

• Maternal thyroid disease: Women with thyroid disease or who are treated for thyroid disease while they are pregnant have a higher chance of having an infant with craniosynostosis, compared to women who don’t have thyroid disease.
• Certain medications: Women who report using clomiphene citrate (a fertility medication) just before or early in pregnancy are more likely to have a baby with craniosynostosis, compared to women who didn’t take this medicine.

The Centers for Disease Control and Prevention (CDC) continues to study birth defects, such as craniosynostosis, and how to prevent them. If you are pregnant or thinking about becoming pregnant, talk with your doctor about ways to increase your chances of having a healthy baby.

Researchers estimate that about one in every 2,500 babies is born with craniosynostosis in the United States. Some babies have craniosynostosis because of changes in their genes. In some cases, craniosynostosis occurs because of an abnormality in a single gene, which can cause a genetic syndrome. However, in most cases, craniosynostosis is thought to be caused by a combination of genes and other factors, such as things the mother comes in contact with in her environment, what the mother eats or drinks, or certain medications she uses during pregnancy.

Understanding the factors that are more common among babies with a birth defect will help us learn more about the causes. Recently, the Centers for Disease Control and Prevention (CDC) reported on important findings from research studies about some factors that increase the chance of having a baby with craniosynostosis:

• Maternal thyroid disease: Women with thyroid disease or who are treated for thyroid disease while they are pregnant have a higher chance of having an infant with craniosynostosis, compared to women who don’t have thyroid disease.
• Certain medications: Women who report using clomiphene citrate (a fertility medication) just before or early in pregnancy are more likely to have a baby with craniosynostosis, compared to women who didn’t take this medicine.

The CDC continues to study birth defects, such as craniosynostosis, and how to prevent them. If you are pregnant or thinking about becoming pregnant, talk with your doctor about ways to increase your chances of having a healthy baby.

Symptoms of craniosynostosis are:

• Unusual skull shape and possibly unusually small head
• Increased pressure inside the skull
• Accumulation of fluid in the skull (hydrocephalus)
• Impaired brain development
• Developmental delays and impaired cognitive development
• Seizures
• Loss of sight

Craniosynostosis usually is diagnosed soon after a baby is born. Sometimes, it is diagnosed later in life.

Usually, the first sign of craniosynostosis is an abnormally shaped skull. Other signs may include:

• No “soft spot” on the baby’s skull
• A raised, firm edge where the sutures closed early
• Slow growth or no growth in the baby’s head size over time

Doctors can identify craniosynostosis during a physical exam. A doctor will feel the baby’s head for hard edges along the sutures and unusual soft spots. The doctor also will look for any problems with the shape of the baby’s face. If he or she suspects the baby might have craniosynostosis, the doctor usually requests one or more tests to help confirm the diagnosis. For example, a special X-ray test, such as a CT or CAT scan, can show the details of the skull and brain, whether certain sutures are closed, and how the brain is growing.

Many types of craniosynostosis require surgery. The surgical procedure is meant to relieve pressure on the brain, correct the craniosynostosis, and allow the brain to grow properly. When needed, a surgical procedure is usually performed during the first year of life. But, the timing of surgery depends on which sutures are closed and whether the baby has one of the genetic syndromes that can cause craniosynostosis.

Babies with very mild craniosynostosis might not need surgery. As the baby gets older and grows hair, the shape of the skull can become less noticeable. Sometimes, special medical helmets can be used to help mold the baby’s skull into a more regular shape.

Each baby born with craniosynostosis is different, and the condition can range from mild to severe. Most babies with craniosynostosis are otherwise healthy. Some children, however, have developmental delays or intellectual disabilities, because either the craniosynostosis has kept the baby’s brain from growing and working normally, or because the baby has a genetic syndrome that causes both craniosynostosis and problems with how the brain works. A baby with craniosynostosis will need to see a healthcare provider regularly to make sure that the brain and skull are developing properly. Babies with craniosynostosis can often benefit from early intervention.

Some children with craniosynostosis may have issues with self-esteem if they are concerned with visible differences between themselves and other children. Parent-to-parent support groups also can be useful for new families of babies with birth defects of the head and face, including craniosynostosis.

Sometimes, special medical helmets can be used to help mold the baby’s skull into a more regular shape. Each baby born with craniosynostosis is different, and the condition can range from mild to severe. Most babies with craniosynostosis are otherwise healthy, though it’s important to note that without treatment, children may have developmental delays.

To further your understanding of your diagnosis and to contribute to cutting-edge research, consider participating in a clinical trial so clinicians and scientists can learn more about causes, symptoms, treatment and prevention. Clinical research uses human volunteers to help researchers learn more about a disorder and perhaps find better ways to safely detect, treat or prevent disease.

All types of volunteers are needed—those who are healthy or may have an illness or disease—of all different ages, sexes, races and ethnicities to ensure that study results apply to as many people as possible, and that treatments will be safe and effective for everyone who will use them.

For information about participating in clinical research, visit NIH Clinical Research Trials and You. Learn about clinical trials currently looking for participants at Clinicaltrials.gov.