Craniosynostosis

Topic Overview

What is craniosynostosis?

A baby's skull has 5 thin bony plates that are held together by a fiber-like material called sutures . The sutures allow a baby's skull to expand as the brain grows. Over time, the sutures harden and close (fuse) the skull bones together. When a fetus or baby has craniosynostosis (craniostenosis), one or more of these sutures close too soon. This causes the baby's head to become abnormally shaped.

The effects of craniosynostosis on a fetus or baby depend in part on how many of the skull sutures are affected.

• Most often, craniosynostosis affects only one suture. More than half of all cases involve the sagittal suture.¹ The sagittal suture runs across the top of a baby's head from front to back. The baby's brain usually develops normally in these cases, but the head becomes abnormally shaped. The skull may become long and narrow or very flat and broad in front or back or on the sides. This depends on which suture closes prematurely.
• Craniosynostosis can develop along more than one suture. When more than one suture closes prematurely, the baby's brain may not be able to grow at its expected rate. In addition, pressure may build up around the brain, causing brain damage, seizures, blindness, and developmental delays. Over time, this can lead to permanent disabilities if the condition is not treated. A baby with more than one suture affected by this condition may have facial defects, such as a misshapen nose or jaw.

What causes craniosynostosis?

Doctors do not fully understand what causes craniosynostosis. Up to 20% of babies with craniosynostosis have inherited a genetic trait from one or both parents that results in the condition.²

Some cases of craniosynostosis may be related to fetal growth or position or other conditions during pregnancy. Fetuses that lie in a breech position while in the womb, are carried by mothers who smoke or who live at a high altitude during pregnancy, or are twins may have an increased risk of developing craniosynostosis.

Craniosynostosis is one of the most common physical deformities of a fetus or newborn, occurring in about 1 in every 2,000 to 2,500 births.³

What are the symptoms?

The most common sign of craniosynostosis is an irregularly shaped head at birth or within the first few months of life. This may be the only sign of the condition.

Although most cases of craniosynostosis are diagnosed based on an irregularly shaped head, some babies become ill. This can happen when more than one suture closes too early. This limits the brain's ability to grow and causes pressure on the brain. As pressure builds on the brain, your baby may:

• Vomit.
• Become sluggish, sleep more, and play less.
• Become irritable because of head pain.
• Develop swollen eyes or problems moving the eyes or following objects.
• Have problems hearing.
• Breathe noisily or have periods of not breathing (apnea).

In extremely severe cases, a baby may have seizures, blindness, and developmental delays and disabilities.

How is craniosynostosis diagnosed?

You or your doctor may notice that your baby has an irregular head shape at birth or shortly afterward. Or, your doctor may identify it later at a regular well-child checkup. Just because your baby has an irregularly shaped head doesn't mean he or she has craniosynostosis. A misshapen head may be caused by how your baby was positioned in your womb, the birth process, and/or sleep position during infancy. A misshapen head caused by any of these factors usually gets better on its own or is easily treated.

Your baby's doctor will measure the baby's head at birth and during well-child exams. He or she will also feel and examine the lines between the bony plates of the baby's skull (sutures) and the soft spots (fontanelles).

If your baby's skull is severely misshapen at birth or slight irregularities do not improve over time, your baby's doctor may order a skull X-ray, CT scan, or MRl to help determine whether craniosynostosis is the cause. In addition, your baby's doctor may ask you questions about your medical history to determine whether your baby may have inherited a genetic form of craniosynostosis.

How is it treated?

Surgery is the usual treatment for craniosynostosis. It works best when it is performed when your baby is as young as possible.

Frequently Asked Questions

Symptoms

The most common sign of craniosynostosis is an irregularly shaped head. You may also be able to feel a ridge along the skull where the suture has closed. There may be no other symptoms when craniosynostosis affects only a single suture. Misshapen heads can also be caused by other factors or conditions that are unrelated to craniosynostosis, such as the birthing process or your baby's sleep position.

Although most cases of craniosynostosis are diagnosed based on an irregularly shaped head, illness may also be a sign. Craniosynostosis is usually more severe when more than one suture closes too early. This significantly restricts the skull's ability to expand as the brain grows. As pressure builds on the brain, your baby may:

• Vomit.
• Become sluggish, sleep more, and play less.
• Become irritable because of head pain.
• Develop swollen eyes or problems moving the eyes or following objects.
• Have problems hearing.
• Breathe noisily or have periods of not breathing (apnea).

When the pressure is very severe, it may cause brain damage and other problems, including seizures, blindness, and developmental delays. Untreated craniosynostosis may cause permanent disabilities.

Exams and Tests

The effects of craniosynostosis are often visible at birth or shortly afterward. In some cases a doctor may notice an irregularly shaped head during a routine well-child checkup in the first few months of life. Your baby's doctor may try to rule out other factors or conditions that can cause a misshapen head, such as those related to the birthing process or an infant's sleeping position.

Your baby's doctor will examine:

• The appearance of each side of your baby's face and head.
• Your baby's skull (sutures ) and the soft spots (fontanelles).
• The top and sides of the head where sutures are located to determine if there are unusual ridges or bumps.

Your baby's doctor will also ask you questions about your medical history to help determine whether your baby has inherited craniosynostosis. To confirm a diagnosis, your baby's doctor may order one or more of the following tests:

• Skull X-ray. This type of X-ray is usually the first test done because it can often show whether the sutures on the baby's skull are open or closed.
• CT scan. This test shows the skull shape and sutures in greater detail than an X-ray, so it often is done if the skull X-ray is unable to show clearly whether the sutures are open or closed.
• MRI. An MRI scan of the head may be done to check whether the baby has developed any problems within the brain. Although rare, prematurely closing sutures can create these types of problems if the skull's growth is severely restricted.

If your baby has been diagnosed with craniosynostosis:

• Ask your doctor about genetic counseling. Craniosynostosis is associated with genetic disorders in up to 20% of cases.¹ Having one baby with craniosynostosis increases your chance of having another baby with this condition.
• Watch for signs of increased pressure on your baby's brain, such as vomiting, sluggishness, and swelling around the eyes. Call your doctor immediately if any of these signs develop.
• Have your child's hearing checked because there's a chance of hearing loss. The United States Preventive Services Task Force recommends that all newborns be screened for hearing loss.⁴

Treatment Overview

Surgery is the usual treatment to correct craniosynostosis. The surgeon removes strips of bone in the skull to create artificial sutures, which relieves pressure on the brain and allows the skull to expand normally. After surgery, your baby's skull should return to its normal shape and continue to grow without deformity.

The timing of surgery is very important. Usually, the earlier the diagnosis and surgery, the better the results. When done early, surgery not only corrects your baby's head shape but also may help prevent complications, such as developmental delays or permanent disabilities.

Several factors will help determine the timing of the surgery to correct craniosynostosis, including how severe the condition is, what your doctor recommends, and what your preferences are.

• If only one suture has closed prematurely and there is no evidence of pressure on your child's brain, your baby's doctor may recommend waiting to see whether your baby's head shape returns to normal without treatment. During this time, your baby may wear devices, such as a specially designed helmet, to help the skull resume its normal shape. However, your child may eventually need surgery.
• Surgery to correct only one suture that has closed too soon may be done when the baby is between the ages of 3 months and 1 year.
• Surgery may be needed before a baby is 6 months of age if craniosynostosis affects more than one suture. This is a more severe form of the condition and usually causes pressure on the child's brain.
• If the pressure building on the brain is severe enough to cause brain damage, your baby will need surgery as soon as possible.

Most babies with craniosynostosis need only one surgery to correct the condition, and complications are not common. However, if complications develop, they are often related to excessive bleeding or injury to the baby's eyes or brain.

Newer surgical techniques for craniosynostosis are less invasive than traditional surgery. They generally result in less blood loss and fewer risks, and may be especially useful for treating babies who are 3 months of age and younger. One such technique, endoscopic-assisted strip craniectomy, sometimes requires the baby to wear a custom-made helmet after surgery until he or she is about 1 year of age.⁵

Occasionally a child requires additional surgery or other treatments. Often this is because the craniosynostosis is severe, surgery was delayed, or complications have developed.

Counseling or support groups may help you manage the stress related to having a child with craniosynostosis. Ask your doctor about contacting support groups or other parents of children with craniosynostosis.

Home Treatment

The only treatment for craniosynostosis is surgery. There are things you can do at home before your child's surgery to help make your child more comfortable and to ensure proper healing after surgery.

Ask your doctor to show you before-and-after pictures of other children who have had the same type of surgery. This may help you prepare for your child's appearance right after he or she has surgery. Photos can also encourage you by showing the positive results that other children have experienced from surgery.

Talk with your baby's doctor about the details of surgery for craniosynostosis and what you can expect afterwards.

At the hospital:

• Stay with your baby as much as possible before surgery.
• Comfort your child, and provide gentle reassurance.
• Have some of your child's familiar or treasured objects, such as blankets or stuffed animals, with you at the hospital.
• Talk to your child and be involved in his or her care. This will help your child get well, and it will make you feel better. It will also help you be more comfortable caring for your child when he or she returns home.
• Talk to the health professionals treating your baby about:
  • Anything you do not understand.
  • How to provide comfort for your child when you are not present.

After surgery, continue to comfort and reassure your child during recovery in the hospital. Be prepared for how your child will appear right after surgery. There may significant swelling, some bruising, and a large bandage covering his or her skull. Your baby may need to wear a helmet. If this is the case, you will receive instructions on how to put the helmet on and take it off.

When your baby returns home:

• Take care of your baby's incision. Clean it regularly and check for signs of infection, such as redness, warmth, pain, or swelling. This incision will leave a scar, which most likely will be completely covered when your baby's hair grows over it.
• Check for signs of complications from surgery, such as bleeding. Also look for signs of pressure on the baby's brain, such as vomiting or increased swelling around the eyes.
• Follow instructions from your doctor regarding how to position your baby after surgery and helmet care (if your baby needs to wear one).
• Call your baby's doctor if you have any questions or concerns about your baby's condition.

Other Places To Get Help

Online Resource

Organization

Related Information

• Growth and Development, Newborn
• Vomiting, Age 3 and Younger

References

Citations

1. Flores-Sarnat L (2002). New insights into craniosynostosis. Seminars in Pediatric Neuorology, 9(4): 274-291.

2. Johnston MV, Kinsman S (2004). Congenital anomalies of the central nervous system. In RE Behrman et al., eds., Nelson Textbook of Pediatrics, 17th ed., pp. 1992-1993. Philadelphia: Saunders.

3. Cunningham ML (2003). Craniofacial disorders section of Clinical genetics and dysmorphology. In CD Rudolph et al., eds., Rudolph's Pediatrics, 21st ed., chap. 10, pp. 748-757. New York: McGraw-Hill.

4. U.S. Preventive Services Task Force (2008). Screening for newborn hearing loss. Available online: http://www.ahrq.gov/clinic/uspstf/uspsnbhr.htm.

5. Jimenez DF, et al. (2002). Early management of craniosynostosis using endoscopic-assisted strip craniectomies and cranial orthotic molding therapy. Pediatrics, 110(1): 97-104.

Other Works Consulted

• Church MW, et al. (2007). Auditory brainstem response abnormalities and hearing loss in children with craniosynostosis. Pediatrics, 119(6): e1351-e1360. Also available online: http://pediatrics.aappublications.org/cgi/content/full/119/6/e1351.

• Greer M (2005). Structural malformations. In LP Rowland, ed., Merritt's Neurology, 11th ed., pp. 592-593. Philadelphia: Lippincott Williams and Wilkins.

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