In this condition, one or more of the flexible joints between the bone plates of a baby's skull close before the brain is fully formed.
Update Date: 01.08.2025
Craniosynostosis (kray-nee-o-sin-os-TOE-sis) is a condition present at birth. It causes one or more of the joints between the bones of a baby's skull to close too early, before the brain is fully formed.
A baby's skull is made up of small plates of bone connected by flexible, fibrous joints called sutures. The sutures allow a baby's skull to get bigger as the brain grows. The sutures usually close when the brain is done growing.
Craniosynostosis usually involves early closing of one cranial suture but can involve more than one. Brain growth continues even when one or more sutures close too early. Open sutures on other sides of the head allow brain growth in those directions. This causes the head to have a shape that's not typical.
Treating craniosynostosis involves surgery to reshape the skull. Early diagnosis and treatment allow the baby's brain enough space to grow and develop.
After surgery, most children develop as expected and have a more average shape to the face and head.
Symptoms of craniosynostosis usually can be seen at birth. They become easier to see during the first few months of a baby's life.
Symptoms and their severity depend on how many sutures are closed and when the closing occurs during brain development. Symptoms can include:
On the top of the head toward the front, some sutures meet at the large soft spot called the anterior fontanel. The anterior fontanel is the soft spot felt just behind a baby's forehead. The next largest fontanel, called the posterior fontanel, is at the back of the head where the other sutures meet. The flexible, fibrous sutures connect the bony plates of the skull.
The term given to each type of craniosynostosis depends on which sutures are affected. Types of craniosynostosis include:
A head shape that's not typical doesn't always mean that a baby has craniosynostosis. For example, if the back of your baby's head appears flattened, it could be the result of spending too much time lying on the back. This can be treated with regular position changes. If the head is very flat on one side, helmet therapy can help reshape the head to a more balanced look.
Your pediatrician or other healthcare professional monitors your child's head growth at well-child visits. Talk with your healthcare professional if you have concerns about your baby's head growth or shape.
Often the cause of craniosynostosis is not known. But sometimes it's related to genetic conditions.
Genetic syndromes that affect a baby's skull development, such as Apert syndrome, Pfeiffer syndrome and Crouzon syndrome, are risk factors for craniosynostosis.
If not treated, craniosynostosis may cause:
The risk of higher pressure inside the skull, called intracranial pressure, from craniosynostosis is small if the suture and head shape are treated with surgery. Babies who have craniosynostosis caused by a genetic syndrome may develop higher pressure inside the skull if treatment doesn't make the skull larger to make room for their growing brains.
If not treated, higher pressure inside the skull can cause:
Craniosynostosis is usually diagnosed by specialists, such as pediatric neurosurgeons or specialists in plastic and reconstructive surgery. Diagnosis of craniosynostosis may include:
Rarely, craniosynostosis may be suspected or diagnosed before birth.
Your child's care team may include a variety of specialists who are experts in managing craniosynostosis. At a center with expertise in diagnosing and treating craniosynostosis, these specialists work together in one place.
Mild craniosynostosis may not need treatment with surgery.
For most babies, surgery is the main treatment. The type of surgery and when it's done depends on the type of craniosynostosis and whether it's part of a genetic syndrome. Sometimes more than one surgery is needed.
The purpose of treatment is to reshape the head, lessen or prevent pressure on the brain, and create room for the brain to grow properly. This process involves planning and surgery.
Imaging studies can help surgeons create a surgical plan. Virtual surgical planning for treatment of craniosynostosis uses high-definition 3D CT scans and MRI scans of your baby's skull to create a computer-simulated surgical plan specific to your baby's needs. Based on that virtual surgical plan, customized models and templates are made to guide the procedure.
A team that includes a specialist in surgery of the head and face, called a craniofacial surgeon, and a specialist in brain surgery, called a neurosurgeon, usually do the surgery. Surgery can be done with endoscopic or open surgery. The exact surgery and when it's done depend on which and how many sutures have closed. Both types of procedures generally have very good cosmetic results with low risk of complications.
To help widen the space between the skull bones once a closed suture has been removed, springs may be placed in the gap. Called spring-mediated cranioplasty, placement of the springs can be done as part of open surgery or endoscopic surgery. Another surgery is needed to remove the springs.
After minimally invasive surgery, your baby has regular office visits to fit a series of helmets to help shape the skull. The surgeon talks with you about how long helmet therapy is needed based on how quickly the head shape responds to treatment. Usually a baby wears a helmet 23 hours of each day for about a year. If open surgery is done, usually no helmet is needed afterward.
When you learn that your baby has craniosynostosis, you may have a range of emotions. You may not know what to expect. Information and support can help.
To help you prepare and care for your baby:
Sometimes a pediatrician may suspect craniosynostosis at a routine well-baby visit. Or you may make an appointment because you have concerns about your baby's head growth. Your healthcare professional can refer you to a specialist for diagnosis and treatment.
Here's some information to help you get ready for your appointment. If possible, take a family member or friend with you. That person can help you remember information and give emotional support.
Before the appointment, make a list of:
Questions to ask might include:
Feel free to ask other questions during the appointment.
Your healthcare professional is likely to ask you questions, such as:
Be ready to answer questions so that you have time to talk about what's most important to you.
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