What is Craniosynostosis

Craniosynostosis (cray-nee-oh-sin-oh-sto-sis) is a condition in which one or more of the bones that make up a baby’s skull in the head fuse together at the point where the bones meet (sutures) before the usual time, limiting the baby’s head growth.

Keeping the skull flexible allows the head to pass through the birth canal and gives the brain room to grow. To give this flexibility, the skull is made up of a number of bones. Normally, the bones of the skull do not finally join or fuse until they are around two years old. However, when a child has craniosynostosis, the sutures fuse before birth. This changes the way the skull grows and can cause pressure on the brain, which, if left untreated, can inhibit brain growth and cause significant visual and neurological complications in the future. The impact and treatment are determined by the suture affected and level of severity.

Types of Craniosynostosis

About 80 to 90 percent of craniosynostosis cases involve only one suture. However, there are lots of different types that can affect more than one suture.

  • Sagittal synostosis (also known as scaphocephaly) - is the most common type of craniosynostosis which occurs when a baby’s head is longer than it is wide.
  • Coronal synostosis – the second most common type of craniosynostosis, affects the front of the head and can result in a flattened forehead on the side of the skull that closes early. A common symptom may be that the baby’s eye socket and nose on that side appears raised.
  • Bi-coronal synostosis – occurs when the sutures on both sides of the baby’s head close too early, causing the the baby’s head to grow broad and short. This type of craniosynostosis may be part of a syndrome or non-syndromic. Syndromic craniosynostosis, which is linked to genetics, is more likely to involve multiple sutures or bilateral coronal sutures.
  • Lambdoid synostosis – is a rare type of non-syndromic craniosynostosis that occurs when one of the sutures at the back of the head fuses before birth. A common symptom may be that the baby’s head may be flattened on the back side.
  • Metopic synostosis (also referred to as trigonocephaly or metopic suture craniosynostosis) - one of the rarest types of craniosynostosis occurs from the baby’s nose to the suture at the top of the head, causing the baby’s head to appear narrow in the front and broad in the back (triangle shaped). In normal development, this suture closes first, and a ridge in this area is not always a sign of craniosynostosis.
It is possible for one or more sutures to be affected. Each type looks different, and the symptoms can range from mild to severe.

What causes Craniosynostosis?

The cause of craniosynostosis in most infants is unknown, but it can sometimes be linked to genetic disorders.
  • Non-syndromic craniosynostosis is thought to be caused by a combination of genes and environmental factors.
  • Syndromic craniosynostosis is thought to be linked to genetic syndromes which usually include other physical and health impairments. Common syndromes include Apert syndrome, Pfeiffer syndrome or Crouzon syndrome, which can affect a baby's skull development.
The following are common symptoms of craniosynostosis:
  • a distorted skull shape
  • an unusual feel to the fontanel, or “soft spot” on the infant’s skull
  • early disappearance of the fontanel
  • slower growth in the head compared to the body
  • hard ridge forming along the suture, depending on the type of craniosynostosis
The condition may be identified during apre-natal ultrasound scan or at birth, or a newborn may show no symptoms or signs at all, but the condition may become noticeable in the first few months of life.

A doctor will measure the infant’s head and monitor their growth at each visit during the first year. From here, they can identify any abnormalities and take appropriate action.


To diagnose craniosynostosis, a doctor will normally look at and measure the baby’s head and feel for ridges in the sutures around the skull.

Additional tests may be required to confirm the diagnosis in greater detail. Imaging tests, such as CT scans and X-rays, can show which sutures have fused. This is important if surgery is likely. Since there may be genetic factors, the doctor may take a sample of the baby’s blood for genetic testing.


Custom-made helmets

If your baby has positional plagiocephaly, which means the cranial sutures are open and the head shape is abnormal, your doctor may recommend a custom-made helmet to help reshape your baby’s head. At the Steeper Clinic, we offer the world-leading STARband™ helmet/cranial to gently guide your baby’s head growth and shape.

If this treatment is possible, our clinic in Leeds offers full support for craniosynostosis. Our clinicians have been fully trained to provide the best advice and can also assess your child free of charge and determine the severity levels of your baby's head shape.

For most cases of craniosynostosis, surgery is the primary treatment. Your doctor will recommend the necessary treatment once they have conducted a full examination, which may include an x-ray, CT scan, developmental assessment and eye examination.

The type and timing of surgery depends on the type of craniosynostosis and whether there's an underlying genetic syndrome. Sometimes more than one surgery is required.

There are four designated specialist hospitals in England and one in Scotland, including:
  • Alder Hey Children’s Hospital
  • Great Ormand Street Hospital for Children
  • Oxford Children’s Hospital
  • Birmingham Children’s Hospital
  • Royal Hospital for Children in Glasgow

There are other centres that offer surgical treatment of craniosynostosis, and we are proud to support the cranial facial team at Leeds Teaching Hospitals.

If you live outside of the UK, talk to your doctor about how to get a referral to a local specialist. If you are not resident in the UK, you cannot receive treatment on the NHS.

Posterior Vault Expansion
Posterior vault expansion has been traditionally used in the UK and is a type of operation used to enlarge the space within the skull to allow the brain to grow and develop.

Strip Craniectomy
Recent changes in practice in the UK mean that babies are now being offered a less invasive surgery that removes the fused section of the skull only. The shape of the head is then moulded using a cranial remoulding orthosis such as a STARband or STARlight helmet.

This treatment is not always funded by your local NHS trust. If you are offered this treatment and are advised to source a cranial remoulding orthosis for after surgery, you can call to speak to one of our trained clinicians who will be able to advise you further.

Our Process
Once your baby has been scheduled for endoscopic strip craniectomy we would perform  a pre-op scan. Once the surgery has been completed, we would take a post op scan. These scans are used to manufacture your baby's STARlight helmet, which will be fitted within two weeks of your surgery date.

At the Steeper Clinic, we use the SmartSoc™ system, which uses patented CurveCapture™ technology which converts 2D images into 3D models.

This scan will be used to manufacture a STARband helmet that is tailored to your baby's specific needs and will be specific to the stage of treatment and sutures involved. We will be able to monitor correction throughout treatment and send reports to your craniofacial team to keep them updated.

During treatment, frequent appointments are required to monitor the fit of the STARlight/ STARband orthosis. We anticipate that three orthoses will be required, with treatment continuing until your baby reaches 18 months old.