What Is Craniosynostosis?

A birth defect that causes the joints in your baby’s skull to fuse prematurely

Craniosynostosis is a birth defect that affects the fibrous joints in your baby’s skull. Normally, the joints in your baby’s skull, known as sutures, are flexible and allow the brain to grow. They harden and become bone around the time your little one turns 2 years old.

In craniosynostosis, one or more of the sutures fuse together prematurely before the brain is fully formed. When this happens, your baby’s brain will continue to grow, causing problems with brain and skull growth. When the suture fuses too early, the skull bones change, causing a misshapen appearance. The pressure inside of your baby’s head may increase as well.

It’s estimated that about one in every 2,500 babies will experience craniosynostosis.

Fortunately, craniosynostosis is treatable with early diagnosis and treatment. Your doctor may recommend surgery to correct the shape of the head and to ensure there is enough room for your baby’s brain to continue to develop.

Macro view of mothers hands holding newborn boy's head

Cavan Images / Getty Images

Types of Craniosynostosis

Craniosynostosis usually involves one fused suture, and the type depends on which suture is affected. Rarely, several sutures fuse, and this is usually caused by a genetic condition.

The types of craniosynostosis include the following:

  • Sagittal craniosynostosis is the most common type of craniosynostosis and affects the sagittal suture that runs from the front to the back of the head. It results in a long, narrow head.
  • Coronal craniosynostosis affects one or both of the coronal sutures, which run from the ear to the top of the head. This type of craniosynostosis causes the forehead to appear flattened and bulging on the affected side.
  • Metopic craniosynostosis affects the metopic suture, which runs from the top of the bridge of the nose up to the top of the head. This type of craniosynostosis causes the forehead to look triangular and widens the back of the head. This is a rare type of craniosynostosis.
  • Lambdoid craniosynostosis is a rare type of craniosynostosis and affects the lambdoid suture. This suture runs along the back of the head, and premature fusing causes one side of the head to appear flat and one ear to be higher than the other. This type is often associated with a genetic disorder.

Craniosynostosis Symptoms

Symptoms of craniosynostosis depend on which sutures in your baby’s head have fused, as well as how developed their brain is. You will most likely notice the symptoms when your baby is born, but some children do not show signs until their first weeks or months after birth.

Common symptoms of craniosynostosis include:

  • A misshapen head and skull
  • A disappearing fontanel on your baby’s head
  • A hard ridge along the fused suture line
  • Slowed head growth while the body continues to grow

Rare symptoms may include:

  • Sleepiness or fatigue
  • Irritability and crying
  • More prominent scalp veins
  • Poor feeding
  • Projectile vomiting
  • Increased head size (circumference)
  • Developmental delay

Causes

In most cases, the cause of craniosynostosis is unknown. Experts believe that craniosynostosis is usually caused by a combination of genetic and environmental factors. Changes in the genes, as well as the health of the mother, may affect a baby’s risk of having craniosynostosis.

According to the Centers for Disease Control and Prevention, recent studies have found that women who are treated for thyroid disease during their pregnancies are at higher risk of having a baby with craniosynostosis. Certain medications, such as the fertility treatment clomiphene citrate, may also increase a woman’s risk of having a baby with craniosynostosis. Talk with your obstetrician about your risk factors and what steps, if any, you can take to lower them.

Syndromic craniosynostosis is caused by an underlying genetic disorder such as Pfeiffer syndrome or Carpenter syndrome. These conditions are serious and usually cause several other physical and cognitive problems as well.

Is a Misshapen Head Always Caused by Craniosynostosis?

If you notice that your baby’s head appears to be misshapen, it may not be craniosynostosis. Babies who spend most of the day on their backs may develop a flattened back of the head. This is usually treated with other physical positions like tummy time and occasionally a helmet. See your pediatrician if you have any concerns about the shape of your baby’s head.

Diagnosis

Craniosynostosis is often diagnosed at birth, but infants may be diagnosed later during the first year as well.

Your baby’s doctor will be able to detect craniosynostosis during a physical exam. Your doctor will start by feeling for hard ridges along your baby’s suture lines. They will use a tape measure to measure the circumference of your baby’s head to determine if it falls into the healthy range.

Because craniosynostosis can sometimes be a symptom of a neuromuscular disorder, your doctor will likely perform a full neuromuscular exam to rule out other conditions as well.

Your doctor will also take a thorough history and ask several questions about your pregnancy. It may be helpful to keep a list of any family members who have experienced craniosynostosis or any changes in their skull shape.

If your doctor suspects craniosynostosis, they may recommend taking your baby for a CT scan to confirm the diagnosis. It can give your doctor a clearer picture of your baby’s skull and brain. A CT scan with 3D reconstruction is able to show your baby’s sutures and any abnormalities in the brain.

Treatment

Craniosynostosis treatment usually involves surgery to relieve any pressure on the brain and allow it space to grow.

The best time to perform craniosynostosis surgery is usually before your child turns 1 year old because the bones in their skull are still soft and easier to shape. Surgery may be recommended as young as 1 month old for babies with a severe case of craniosynostosis.

Calvarial Vault Remodeling

In calvarial vault remodeling, your child’s surgeon makes an incision in the scalp and then reshapes your child’s head by moving the part of the skull that fused prematurely. The goal is to create a more circular shape.

This procedure can take up to six hours and sometimes requires a blood transfusion. Calvarial vault remodeling is usually performed when your child is about 5 to 6 months old because their skull bones are thick and hard enough to be moved and hold their new shape.

After surgery, your baby will likely spend at least one night in the intensive care unit for monitoring then move to a regular hospital room. Your surgical team will recommend regular follow-up appointments to monitor your child’s head shape and catch any complications early. Your follow-up appointments will likely be scheduled for one, six, and 12 months after surgery.

Endoscopic Craniosynostosis Surgery

Endoscopic craniosynostosis surgery is a minimally invasive surgery that is sometimes available for babies between 2 and 3 months old. During the surgery, the surgeon makes small incisions in your baby’s scalp then uses a small tube called an endoscope to open the fused suture. This surgery usually takes one hour to perform. Your child will be less likely to need a blood transfusion because there is usually less blood loss with this surgery.

After surgery, your child will likely stay in the hospital overnight for monitoring then be discharged. Your baby will need to wear a helmet to help mold and shape the skull into a circular shape. Expect to follow up with your surgical team three, six, nine, and 12 months after the surgery. You will also have several follow-up appointments with your child’s helmet specialist to monitor their head shape and growth.

What to Expect After Surgery 

Immediately after your child’s surgery, they will be taken to a post-anesthesia care unit. The nurses there will let you know as soon as you can see your little one. Expect to see your baby with a dressing wrapped around their head and to seem very groggy from anesthesia. It’s common for babies to experience facial swelling, especially around their eyelids, after surgery. They may also require a blood transfusion.

Does My Child Definitely Need Surgery?

A child with mild craniosynostosis may not require any treatment at all. As your child’s head grows and they develop more hair, the shape of their head may appear normal. As long as they are not experiencing any complications from the condition, your pediatrician may recommend holding off on any surgical treatments.

Once your baby is ready to be transferred to the intensive care unit, the team there will monitor them for surgical complications such as a fever, irritability, vomiting, and decreased alertness. The medical team will inspect your child’s incisions to make sure there is no sign of infection. Signs of infection may include redness, swelling, and oozing pus. If your baby experiences any of these symptoms once you are discharged, call your doctor right away.

Prognosis 

Your baby’s prognosis will depend on which type of craniosynostosis they have, how severe it is, and how early it is diagnosed and treated. Most cases of craniosynostosis are treatable and do not lead to long-term health problems or complications.

Severe craniosynostosis can affect your baby’s brain growth and development, so it will be important to stay in close contact with your pediatrician and healthcare team to monitor any problems.

Possible complications of craniosynostosis include:

  • Permanent head or facial abnormalities
  • Developmental delays
  • Vision problems
  • Seizures
  • Breathing problems

Coping 

Hearing that your child has a health condition that affects their skull is overwhelming, to say the least. Research shows that having a child with craniosynostosis is stressful for parents, especially when they perceive the condition to be noticeable to others.

Finding ways to cope can help relieve some of your fears while pursuing treatment for your child. A 2020 study found that while parents experienced significant stress during the diagnosis and treatment period, there were actions they could take to cope.

Some helpful tips for coping with a diagnosis of craniosynostosis in your child include the following:

  • Write down any questions you have before your child’s medical appointments.
  • Keep a notebook of notes from your child’s appointments.
  • Ask your child’s surgeon to show you a model of a skull to explain the procedure.
  • Request a point person or specialized nurse whom you can contact with questions or concerns between appointments.
  • Ask for regular updates during your child’s surgery.
  • Connect with a craniosynostosis support group or online group.

Frequently Asked Questions

How common is craniosynostosis?

Craniosynostosis is relatively common. It’s estimated that about one in every 2,500 babies will experience craniosynostosis.

When is craniosynostosis diagnosed?

Craniosynostosis is usually diagnosed at birth, but it can also develop later into infanthood. Your pediatrician may diagnose the condition during a well-child visit in your child’s first year of life. As the parent, you may notice that your baby's head shape starts to change as they grow. Always talk with your doctor if you develop any concerns.

What should you expect after craniosynostosis surgery?

After surgery, your child will have a dressing wrapped around their head and seem very groggy. Your baby may require a blood transfusion because blood loss during surgery can be common. It is normal for babies to have facial swelling after surgery too.

Who is at risk of craniosynostosis?

The risk of craniosynostosis goes up in babies who are born prematurely, as well as infants who have a family history of craniosynostosis or genetic disorders. Your child’s risk may go up if their mother required certain fertility medications or developed thyroid disease during their pregnancy.

Summary

Craniosynostosis is a birth defect where your baby's skull fuses too soon, limiting the amount of space where their brain can grow. It's usually diagnosed at birth, but some cases may not be detected until the child is 1 year old or older. There are many treatment options for this condition, and your baby has the best outcome when it's treated as soon as possible.

A Word From Verywell

Craniosynostosis occurs when the bones in your baby’s skull fuse too early. This can be a scary diagnosis for any parent to hear. Once your baby has been diagnosed, you will work with your pediatrician and surgeon to determine the needed treatment and follow-up care.

Most babies who are diagnosed and treated early go on to lead healthy lives without complications. Because this condition can be very stressful for parents, connecting with an in-person or online support group may be helpful.

Was this page helpful?
Article Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Centers for Disease Control and Prevention. Facts about craniosynostosis. Updated October 23, 2020.

  2. Nationwide Children’s. Craniosynostosis: Causes, symptoms, diagnosis and treatment.

  3. Cleveland Clinic. Craniosynostosis: Symptoms, diagnosis, treatment. Updated March 30, 2021.

  4. John Hopkins Medicine. Craniosynostosis

  5. Kajdic N, Spazzapan P, Velnar T. Craniosynostosis - Recognition, clinical characteristics, and treatment. Bosn J Basic Med Sci. 2018 May 20;18(2):110-116. doi:10.17305/bjbms.2017.2083

  6. Governale LS. Craniosynostosis. Pediatr Neurol. 2015 Nov;53(5):394-401. doi:10.1016/j.pediatrneurol.2015.07.006

  7. Proctor MR. Endoscopic craniosynostosis repair. Transl Pediatr. 2014 Jul;3(3):247-58. doi:10.3978/j.issn.2224-4336.2014.07.03

  8. Garrocho-Rangel A, Manriquez-Olmos L, Flores-Velazquez J, Rosales-Berber MA, Martinez-Rider R, Pozos-Guillen A. Non-syndromic craniosynostosis in children: Scoping review. Med Oral Patol Oral Cir Bucal. 2018 Jul 1;23(4):e421-e428. doi:10.4317/medoral.22328

  9. National Institute of Neurological Disorders and Stroke. Craniosynostosis information page. Updated March 27, 2019.

  10. Kuta V, Curry L, McNeely D, Walling S, Chorney J, Bezuhly M. Understanding families' experiences following a diagnosis of non-syndromic craniosynostosis: a qualitative study. BMJ Open. 2020 Sep 24;10(9):e033403. doi:10.1136/bmjopen-2019-033403