How Craniosynostosis Is Diagnosed

Craniosynostosis is a common birth defect that affects the flexible joints in your baby’s skull. These flexible joints, known as sutures, usually remain open until your little one is about 2 years old. In the case of craniosynostosis, one or more sutures fuse together prematurely, leading to skull malformation and possibly increased pressure on the brain.

Craniosynostosis is usually diagnosed with a physical exam. It may be diagnosed at birth or sometime during your child’s first year of life. Your doctor may recommend a CT scan to confirm the diagnosis as well. 

Early diagnosis is essential to beginning treatment early, correcting the abnormality, and avoiding complications.

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Self-Checks/At-Home Testing

While there is no proven method for testing for craniosynostosis at home, you may notice that the shape of your baby’s head appears uneven or is changing. Any change or worsening of your baby’s head shape should always be checked out by your pediatrician

The type of craniosynostosis depends on which sutures fuse together early, and each looks different. Observable signs of each type of craniosynostosis can include:

  • A long, narrow head (scaphocephaly) is a sign of sagittal craniosynostosis. 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.
  • A flat forehead with a long, broad head is a sign of coronal craniosynostosis. The right and left coronal sutures run from each ear to the sagittal suture at the top of the head.
  • A flat back of the head (plagiocephaly) is a sign of lambdoid craniosynostosis. The lambdoid suture runs along the backside of the head. 
  • A triangular-shaped head is a sign of metopic craniosynostosis. The metopic suture runs from the baby’s nose to the sagittal suture at the top of the head.

Other common signs of craniosynostosis include a hard ridge along your baby’s head, an absent or disappearing soft spot (fontanel), and a face that looks asymmetrical. 

A 2020 study found that parents of babies with craniosynostosis often noticed an abnormal head shape in their infants but felt dismissed by medical providers. Parents reported feeling frustrated that they knew something was wrong, but their physician did not share their concerns. If you are worried about your child’s head shape, make an appointment with your pediatrician and ask about examining your child for craniosynostosis. 

You may also notice the following symptoms in your baby:

  • Irritability
  • High-pitched cry
  • Sleepiness
  • Prominent scalp veins
  • Poor feeding
  • Projectile vomiting
  • Developmental delays 

Physical Examination

Craniosynostosis can be diagnosed with a physical exam. Your doctor will thoroughly examine your little one’s scalp, looking for any prominent veins that could indicate craniosynostosis. They will also feel along the suture lines, noting any hard ridges.

Your doctor will feel the soft spots on your baby’s head. These are usually soft to the touch, much like a ripe peach, but will feel hard and rigid when the suture has fused. The nurse will usually measure your baby’s head circumference as well. 

Because craniosynostosis can lead to increased pressure around your baby’s brain, your doctor will examine your child for increased intracranial pressure and may recommend an ophthalmological exam of your child’s eyes. Craniosynostosis is sometimes part of a genetic disorder, so your doctor may perform a neuromuscular exam as well. 

In addition to a physical exam, your doctor will take a thorough history. It may be helpful to bring notes with you about your pregnancy, birth experience, and family history. Your doctor may also recommend confirming the diagnosis with a CT scan.

Labs and Tests

If your doctor suspects that your child’s craniosynostosis is part of a genetic disorder, they may order additional lab tests to learn more. Genetic disorders like Pfeiffer syndrome and Carpenter syndrome cause premature fusing of the sutures. 

Babies who have craniosynostosis involving multiple sutures are more likely to have a genetic disorder. In these cases, genetic testing is recommended to evaluate the following genes:

  • FGFR3
  • FGFR2
  • TWIST
  • MSX2
  • TGFB2
  • ERF
  • RUNX2
  • EFNB1
  • FAM20C
  • LMX1B

Imaging

Imaging studies are usually ordered before performing craniosynostosis surgery. 

CT With 3D Reconstruction 

The most accurate way to diagnose craniosynostosis is with computed tomography (CT) with three-dimensional (3D) reconstruction. This test allows your child’s medical team to visualize all of their suture lines and see if they are open or have already fused. A CT scan also shows any abnormalities in the brain.

Because craniosynostosis can lead to increased pressure in the brain, this is important to be able to assess. Magnetic resonance imaging (MRI) may also be used to examine your child’s brain. 

Cranial Suture Ultrasound 

Your doctor may recommend a cranial suture ultrasound to evaluate your child’s suture lines. This test is faster than a CT scan and does not involve radiation. Talk with your medical team about which test is best for your child.

Differential Diagnoses

An abnormal head shape does not always mean that your baby has craniosynostosis. A much more common explanation is positional plagiocephaly.

Positional plagiocephaly is a benign condition that occurs when a baby lies in the same position most of the time. This can cause the soft, flexible skull bones to flatten, and often occurs in the back of the head.

Positional plagiocephaly may appear like craniosynostosis, but is treated differently. It does not affect your baby’s brain development and does not require surgery. This condition is usually treated with helmet therapy.

You may be able to prevent this condition by changing your baby’s position throughout the day. Encouraging daily “tummy time” with your little ones helps them develop their posture muscles while lifting their head up.

Summary

Craniosynostosis is a birth defect that can be diagnosed with a physical exam. You may want to watch out for any abnormalities in your baby’s head and reach out to your pediatrician if you are concerned about craniosynostosis. Sometimes allowing your baby to lie flat for long periods time can also cause flatness on the back of the head that’s not related to craniosynostosis.

Frequently Asked Questions 

When is craniosynostosis diagnosed?

Craniosynostosis is often diagnosed at birth, but may develop later on as well. Your doctor may diagnose your baby during a well-child visit in the first year of life. 

What is craniosynostosis surgery?

Craniosynostosis surgery involves correcting the shape of your child’s head while relieving any increased pressure on the brain. During one type of craniosynostosis surgery called calvarial vault remodeling, your child’s surgeon will make an incision in your baby’s scalp and then move the skull bones into a more circular shape.

What should you expect after craniosynostosis surgery?

Recovery from craniosynostosis surgery depends on which type of surgery your child had. After cranial vault remodeling, your child will likely spend a night in the intensive care unit, followed by a hospital stay in a regular hospital room for monitoring. 

How long does it take babies to adjust to a helmet for craniosynostosis?

Your doctor will most likely recommend that your baby wear their helmet for 23 hours a day, including during sleep. Each child will adjust to wearing the helmet in their own time. Ask your physician or helmet specialist for tips on helping your baby feel more comfortable.

A Word From Verywell

Craniosynostosis is a birth defect that affects the shape of your baby’s head. It is usually diagnosed with a physical exam. Your doctor can tell if your baby has craniosynostosis and what type they have based on the appearance of their head.

Your doctor may also recommend a CT scan to confirm the diagnosis. Additional imaging will be done prior to surgery if your child needs it.

Parents often notice the abnormal shape of their child’s head first. Don’t hesitate to talk with your doctor if you have any concerns.

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Article Sources
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