What Is Coronal Craniosynostosis?

Coronal craniosynostosis is a type of craniosynostosis, a birth defect affecting the flexible joints in a baby’s skull. These joints, known as sutures, usually stay flexible until your child’s second birthday. In craniosynostosis, sutures fuse prematurely, turning into hard bone. This can lead to a misshapen head and possibly increased pressure on the brain.

Coronal craniosynostosis occurs when one or both (right and left) of the coronal sutures fuse early and is the second most common type of craniosynostosis. The coronal sutures run from the ear up to the top of the head on both sides. Coronal craniosynostosis usually occurs on one side of the head and causes the forehead to appear flattened on the affected side. The unaffected side has a very prominent forehead. When both coronal sutures fuse, the forehead looks tall and flat.  

Coronal craniosynostosis is usually treated with surgery to correct the skull’s shape and relieve any increased pressure on the brain.

Types of Coronal Craniosynostosis

Coronal craniosynostosis may occur on its own or as part of a genetic disorder. Nonsyndromic coronal craniosynostosis refers to a random birth defect that often has an unknown cause, while syndromic coronal craniosynostosis is usually a symptom of a genetic disorder that may affect other areas of the body as well. 

There are two types of coronal craniosynostosis, depending on whether it affects one or both sides of the head:

• Unilateral coronal craniosynostosis affects the coronal suture on one side of the head. It results in a rotated appearance to the face with a flattened forehead on the affected side. You may also notice that your baby’s eye appears higher on the affected side.
• Bilateral coronal craniosynostosis affects both coronal sutures on either side of the head and is the most common form of syndromic craniosynostosis. It causes a short, wide head. 

Coronal Craniosynostosis Symptoms

Signs of coronal craniosynostosis may start out mild and worsen over time as your child continues to grow. Symptoms may be present at birth or develop during the first year of life. 

Coronal craniosynostosis causes the forehead and brow to stop growing normally. When this happens, the forehead and brow both appear flattened. If one of the coronal sutures is fused, this flattening appears on the affected side. This causes the forehead on the unaffected side to appear very prominent. The eye socket on the affected side appears higher than the unaffected side. 

Common symptoms of coronal craniosynostosis include:

• A misshapen head and skull
• A flattened forehead and brow
• A disappearing soft spot, or fontanel, on the top of your baby’s head
• A hard ridge along the coronal suture on the side of the head
• Slowed head growth while the body continues to grow

Rare symptoms may include:

• Sleepiness or fatigue
• Irritability and crying
• More prominent scalp veins
• Poor feeding
• Projectile vomiting
• Increased head size (circumference)
• Developmental delay

Causes

Coronal craniosynostosis often occurs without a known cause. Researchers believe it is caused by a combination of genetic and environmental factors. Coronal craniosynostosis is most likely caused by a defect in the hardening process of the skull (cranial) bones. The underlying cause of this defect is unknown and thought to be random. 

However, there are some factors that appear to raise a baby’s risk of having this birth defect. The following risk factors are associated with coronal craniosynostosis:

• Multiple babies in one pregnancy, such as twins or triplets
• A large head size in utero 
• Maternal thyroid disease
• Maternal smoking
• Certain fertility medications, such as clomiphene citrate (Clomid)

Syndromic coronal craniosynostosis is part of a genetic disorder and may be caused by:

• Apert syndrome is a genetic disorder that causes premature fusing of the bones in the skull (craniosynostosis), as well as in the fingers and toes.
• Crouzon syndrome is a genetic disorder that affects the bones, muscles, joints, and cartilage. It often leads to the premature fusing of several sutures in the skull.
• Muenke syndrome is a genetic disorder that causes the premature fusing of the coronal suture, as well as other areas of the skull.
• Pfeiffer syndrome is a rare genetic disorder that causes a baby’s skull bones to fuse together.

Diagnosis

Coronal craniosynostosis can be diagnosed with a physical exam. Your doctor may recommend imaging as well to confirm the diagnosis, especially if surgery is being considered.

During the physical exam, your doctor will carefully examine your child’s head, paying special attention to their forehead and brow. Your doctor will inspect the scalp to look for prominent veins and feel along the coronal suture lines, noting any hard ridges. Your doctor will also feel the fontanel on the top of your child’s head to determine if it is still open. 

Your doctor will also conduct a detailed history to learn about your family history. It may be helpful to bring notes with you. Write down any family members with a history of craniosynostosis, skull abnormality, or genetic disorder. 

To confirm the physical findings, your doctor may recommend a computed tomography (CT) scan of your little one’s head. A CT scan with 3D reconstruction is considered the most accurate way to diagnose coronal craniosynostosis. This test can show both your child’s coronal sutures, as well as any abnormalities in the brain.

If your doctor suspects that your child’s craniosynostosis is part of a genetic disorder, they will refer you for further testing.

Treatment

Coronal craniosynostosis is usually treated with surgery. The goal of surgery is to correct the shape of the skull and allow the brain to grow normally. The two types of surgery available are:

• Endoscopic craniosynostosis surgery uses a small tube called an endoscope to move the skull bones into place. The surgeon will make tiny incisions in your child’s scalp and then insert the endoscope. This surgery is usually recommended when your child is between 2 and 6 months old. This is because the skull bones are still flexible enough to be moved with the endoscope. After surgery, your child will need to wear a helmet for several months as their skull bones grow and harden. 
• Calvarial vault remodeling involves making an incision in your child’s scalp and moving their skull bones into place. This surgery requires a bigger incision, and your baby may need a blood transfusion due to blood loss during surgery. However, a helmet is not necessary during the recovery period. This surgery is usually recommended after your baby has turned 6 months old. 

Timeline

Coronal craniosynostosis is usually diagnosed at birth or during your child’s first year. Treatment will depend on your child’s type of coronal craniosynostosis, how severe the skull malformation is, and when they are diagnosed. A treatment timeline is usually as follows:

• Birth to 1 year: Diagnostic process, including a physical exam and CT scan with 3D reconstruction
• 2 to 6 months: Endoscopic craniosynostosis surgery, after which your child will then need to wear a helmet for several months
• 6 to 12 months: Calvarial vault remodeling

Prognosis

Most babies who are treated for coronal craniosynostosis have successful outcomes without complications. Early diagnosis and treatment are important to ensuring treatment success.

When coronal craniosynostosis is left untreated, babies can experience increased intracranial pressure and long-term complications, including:

• Developmental delays
• Head or facial abnormalities
• Breathing problems
• Vision disorders
• Seizures
• Low self-esteem

Coping

Navigating a serious birth defect with your child is overwhelming for all parents. Finding ways to cope as you work with your medical team to determine your child’s diagnosis and treatment plan may help.

Studies have shown that having a child with craniosynostosis is stressful for parents, especially when the skull abnormality is noticeable to others. A 2020 study found that parents felt considerable stress when they noticed that there was something wrong with their child but felt dismissed by medical providers.

Fortunately, there are steps that parents can take to better support themselves and their families. Because the first doctor’s appointment can be overwhelming, it may help to write down a list of questions so you don't forget anything. Taking notes during the visit has also been found to help ease stress. 

Parents who had a specialized nurse or point person to call with questions in between appointments stated that these phone calls eased their anxiety. Connecting with other families going through the same process or a support group was also helpful. If there are no in-person support groups in your area, look for an online community. The most important thing to remember is to seek support for yourself as you support your child. 

Summary

Coronal craniosynostosis occurs when one or both coronal sutures, which run from each ear to the top of the head, fuse together prematurely. The cause of this condition is unknown, but it may be related to a genetic disorder or certain risk factors such as smoking. However, it can be treated with surgery, and the earlier it takes place, the better the outcome for your child.

Frequently Asked Questions

What is the cost of coronal craniosynostosis surgery?

Surgical costs usually include the surgeon’s fees, hospital costs, and anesthesia fees. According to a 2020 cost comparison, the average total cost for endoscopic craniosynostosis surgery with follow-up care was $50,840. The average cost of calvarial vault remodeling with follow-up care was $95,558. 

What happened when I was pregnant that caused coronal craniosynostosis?

Coronal craniosynostosis is a birth defect that happens randomly. This means that the cause is unknown. This is frustrating for parents who want answers about why their child has this serious condition. It may be helpful to talk with your doctor about undergoing genetic counseling if you plan to have more children in the future. 

How long is the surgery for coronal craniosynostosis?

The length of craniosynostosis surgery depends on which surgery your child is undergoing, as well as how severe their deformity is. Calvarial vault remodeling can take up to six hours, while endoscopic craniosynostosis surgery takes about one hour.

How do you overcome coronal craniosynostosis in pregnancy?

Unfortunately, there is no guaranteed way to prevent it. There are certain factors that raise the risk, such as taking thyroid disease, smoking, and fertility treatments. If you are concerned about your risk, talk with your obstetrician. 

A Word From Verywell

Coronal craniosynostosis is an overwhelming diagnosis to hear about your child. Fortunately, most babies who undergo treatment for this condition go on to live healthy lives without complications. 

Once your baby is diagnosed, your doctor will discuss a treatment plan for you. Treatment usually involves surgery to correct the skull deformity. Endoscopic craniosynostosis surgery is usually performed at between 2 months and 6 months of age, and calvarial vault remodeling is recommended for babies older than 6 months. 

To help ease some of the stress of this diagnosis, ask your medical team about connecting with other families on the same journey or joining a support group.