What Is Craniosynostosis?

Craniosynostosis is a rare and serious condition, seen in about one or two children per 2,000 births. A child is either born with the condition or develops it in their first few months.

Babies' skulls are not fully formed at birth. Instead, pieces of the skull are linked by soft areas called sutures. As a child grows, the sutures allow space for the brain and skull to grow; bones eventually grow where the sutures were. In babies with craniosynostosis, the pieces of the skull that should be separated by sutures have already fused, which means that their brain and skull don't have enough room to grow.

Children can have the condition by itself, called isolated, non-syndromic craniosynostosis, or they can have it along with other health issues or syndromes, called syndromic craniosynostosis. Syndromic craniosynostosis is much rarer. The syndromes most commonly associated with craniosynostosis include:


Types of Craniosynostosis

A child's diagnosis depends on the type of craniosynostosis they have, which is determined by the specific suture that's affected.

Sagittal craniosynostosis

The most common type of non-syndromic, or isolated craniosynostosis, sagittal synostosis is characterized by the early closure of the sagittal suture, the seam that runs from the front to the back of the skull. In children with sagittal craniosynostosis, the head is long and skinny with a rounded forehead. This is called scaphocephaly.

Coronal craniosynostosis

Coronal synostosis is the premature closure of one of the coronal sutures, the seams that run from your baby's ear to the soft spot on their head. If both of a child's coronal sutures close too early, then they have bicoronal synostosis. Children with one coronal suture fused are said to have unicoronal synostosis and will have an pulled back and higher brow with a flattened forehead on the side of the fused suture.

Metopic craniosynostosis

Metopic synostosis is the early closure of the metopic suture, which runs from the top of the head down the forehead to the area between the eyes. Children with metopic craniosynostosis have an angled and narrow forehead like the front of a boat with eyes that appear close together and brows that are pulled back on the side. When viewed from the top, these children have triangular or “tear drop” shaped heads. This is called trigonocephaly.

Lambdoid synostosis

Lambdoid synostosis, the premature fusion of one or more of the lambdoid sutures, on the back of the skull, is the rarest form of non-syndromic craniosynostosis. It is the most rare form of non-syndromic craniosynostosis. It can result in flattening of the back of the head on the side of fusion as well as rounding on the side of the head on the opposite side.

What Causes Craniosynostosis?

The condition begins before the child is born. Doctors don't always know what causes it, but the condition could develop if:

  • There are changes in the baby's genes
  • The mother took medicine for thyroid disease while pregnant, or went through fertility treatment to conceive the baby

Who Is at Risk of Craniosynostosis?

A baby may have a higher risk for the condition if:

  • The mother took a certain thyroid drug during pregnancy
  • The mother used certain fertility drugs to become pregnant
  • One or both parents carry a gene for the condition
  • Someone in the family has the condition
  • The baby has a syndromic condition

What Happens if Craniosynostosis Isn't Treated?

If left untreated, the condition can be life-threatening, as the brain may not have room to grow as it should. This can lead to:

  • Headaches
  • Seizures
  • Vision problems, including blindness
  • Increased pressure inside the skull, leading to brain damage and/or developmental delays

Symptoms & Diagnosis

What are the symptoms of craniosynostosis?

A baby with the condition may have some of the following symptoms:

  • Unusually shaped face or head
  • No soft spot, or a bulging soft spot
  • Raised scalp veins
  • Excessive sleepiness
  • Extreme irritability
  • Poor feeding
  • Vomiting
  • Seizures
  • Missed developmental milestones

While some of these symptoms, such as vomiting and sleepiness, are normal for babies, some, like seizures, are always urgent. If your baby has already been diagnosed with craniosynostosis, and they display any of the above symptoms, you should immediately take them to the doctor.

How do doctors diagnose craniosynostosis?

If your baby was born with the condition, doctors may have noticed it shortly after birth. Some cases are noticed during regularly scheduled doctor visits when the baby is still very young. If your child's pediatrician suspects they may have this condition, they can order diagnostic tests, including:

  • A complete physical exam
  • X-rays of the head
  • A CT scan of the head
  • Genetic testing of the baby, and in some cases of the parents


How do doctors at UPMC Children's Hospital of Pittsburgh treat craniosynostosis?

The Cleft-Craniofacial Center at UPMC Children's Hospital of Pittsburgh treats each case individually, based on your child's specific diagnosis and symptoms.

If your child's case is mild, they may not need treatment right away; more severe cases will require treatment sooner. Many babies with the condition require surgery to separate the skull where the sutures are supposed to be, giving the brain and skull enough room to grow.

A team involved in a case of craniosynostosis may include a:

  • Pediatrician
  • Plastic surgeon
  • Neurosurgeon
  • Audiologist
  • Speech pathologist
  • Social worker

Surgery for craniosynostosis

The treatment approach depends on your child's age and the which suture is affected. In very mild cases, your doctors may decide to observe your child instead of performing surgery. However, most children with isolated, non-syndromic craniosynostosis will need surgery.

Since your child's brain continues to grow at a normal pace, it's important to treat a craniosynostosis in the first few years of life. Left untreated, your child could experience increased pressure on the brain which can cause chronic headaches, developmental delay, seizures, and vision problems.

Treatments vary based on how the condition specifically affects your child, but it's likely that your doctors will recommend surgery. It's important to find a surgeon who specializes in craniofacial surgery. Your doctor at the UPMC Cleft and Craniofacial Center can recommend an treatment plan specific for the needs of your child.

At UPMC Children's Hospital of Pittsburgh, we offer many different techniques to meet your child’s individual needs. These include open cranial vault remodeling procedures such as fronto-orbital advancements, minimally invasive choices, such as endoscopic strip craniectomies and spring-assisted surgery, and craniofacial distraction osteogenesis.

Open Cranial Vault Remodeling

For many children with non-syndromic, or isolated, craniosynostosis, open procedures are required to keep the brain healthy. In these procedures, your surgeon will remove a section of the skull before reshaping it and replacing it in a new position. This surgery is typically performed around 1 year of age.

Minimally invasive Craniosynostosis surgery

For some children with non-syndromic craniosynostosis, minimally invasive procedures may be offered to reshape the skull and provide room to the growing brain. These procedures are performed earlier (3-6 months old) through smaller incisions. They usually have less bleeding and discomfort, and require shorter time in the operating room and shorter stays in the hospital. These techniques require either the placement of a helmet or springs to help reshape the skull after the surgery is over. After 6 months of age, your child is no longer able to have a minimally invasive procedure, so it is important to get referred at an early age if you have concerns.

What questions should I ask before surgery?

Before surgery, you should have a list of questions prepared for your team. Some questions you may want to ask include:

  • Will my child need more than one surgery?
  • How long will we need to be in the hospital?
  • What are possible complications from the surgery?
  • Why is now the best time to do the surgery?


Children who are treated early, before serious complications, can expect to live healthy, happy lives. The key is early treatment and good follow-up. In spite of early treatment, some children will look different because of the shape of their skull. Our social workers can suggest support groups and other resources to help you and your child deal with this issue as they grow.

Contact Us

Meet our team at UPMC Children's Hospital of Pittsburgh's Cleft-Craniofacial Center and learn about our treatment options, or contact UPMC Children's Hospital of Pittsburgh at 412-692-8650.