Syndromic craniosynostosis

What is syndromic craniosynostosis?

Patients with syndromic craniosynostosis, a congenital (present at birth) condition, have more complicated needs than those with isolated (non-syndromic) craniosynostosis. There are several reasons for this. The first is that these patients have globally impaired growth of the skull and facial bones that makes it harder to achieve a lasting correction of the appearance and maintain adequate space in the skull for the growing brain. A patient may need several operations during childhood to “catch up” to where they should be if their skulls and face were growing normally.

Patients with syndromic craniosynostosis frequently have significant additional problems with breathing, hearing, speech and eating. They may also be born with deformed hands and feet which present additional functional and surgical challenges. Patients with so many complex problems require a team of specialists with expertise in each of the child’s problem areas and experience in caring for children with syndromic craniosynostosis.

These syndromes are usually genetic in nature. The problem may occur when a gene mutates, or may be genetically inherited. At a busy craniofacial center like ours, we see even the most rare syndromes, but on this webpage, we will cover only the more common craniosynostosis syndromes.

What are the types of syndromic craniosynostosis?

Craniosynostosis syndromes are usually named after the person who first described it. There are at least 70 conditions that can cause syndromic craniosynostosis.

The most common of syndromes include:

• Apert syndrome

• Crouzon syndrome

• Muenke syndrome

• Pfeiffer syndrome

• Saethre-Chotzen syndrome

These may share some common features. For Crouzon, Apert and Pfeiffer syndromes the patient’s eyes may look abnormally large or prominent. The eyes are actually of a normal size, but the eye sockets are more shallow than normal because of abnormal growth of the bones. This causes the eyes to bulge and appear large, and when this is severe it can become difficult for the eyelids to close which can dry the eyes severely.

These patients also have flatness in the middle of the face caused by poor growth of the upper jaw. The hands and feet may also have deformities.

General considerations

• Brain growth - The brain more than doubles in size in the first year of life, reaching two-thirds of its adult size by age one. It continues to grow rapidly until age two years. After age two the brain grows more slowly and reaches adult size between six to 10 years of age.

• The growing brain is what drives skull growth - The growth causes bone production at the cranial sutures. The biggest concern with craniosynostosis in an infant is the potential for the skull to not grow fast enough to keep up with the rapidly growing brain. If the skull grows too slowly because one or more sutures are closed prematurely, it may result in raised pressure inside the skull that is harmful to the brain. This is called elevated intracranial pressure.

Increased pressure in the skull

The risk of increased pressure in the skull rises greatly with each closed cranial suture. This is because it makes the open sutures work much harder to make bone. Also, patients with syndromic craniosynostosis may have other problems related to the added pressure in the skull. They have a higher risk of:

• Problems in flow of blood from the brain back to the heart

• Problem in draining the fluid that surrounds the brain (hydrocephalus)

• Obstructed upper airways (for example, sleep apnea)

Scheduling surgery

Waiting too long for surgery while elevated pressure is present can cause blindness and learning delays. This makes diagnosis and prevention of elevated pressure in the skull a priority in treating patients with craniosynostosis.

• Elevated pressure in the skull - It can be difficult to know if a child has high pressure in their skull. Signs may be subtle including low activity or alertness, as well as learning delays. This can be a challenge to diagnose in the very young child. The absolute best way to measure the pressure is to do so directly. This requires going into the hospital to put a pressure monitor through a small hole in the skull. Because this is invasive, we use this test only in cases where we are not sure if pressure is present in the skull and the treatment plan will change depending on the presence of elevated pressure.

How is syndromic craniosynostosis treated?

Children with syndromic craniosynostosis require a team of specialists to best manage their care. It is best for a patient to see all of these specialists in one clinic visit. At Children’s Health the entire team sees the patient in a single two-hour visit. Our team then sits in a conference where each specialist talks about the patient’s needs and a collective plan created by all providers is mapped out for the upcoming year.

We always try to anticipate as many problems as possible in order to reduce risks presented by anesthesia in our surgeries. We follow our patients until they are fully grown adults.

Team members include:

• Plastic surgeon

• Neurosurgeon

• Oral surgeon

• Dentist

• Orthodontist

• Ear, nose and throat (ENT) surgeon

• Ophthalmologist

• Speech therapist

• Child psychologist

• Experienced nurses and physician assistants with experience in these disorders

Surgery

What kind of surgery and when to do it depends on each patient’s needs. We perform a limited skull surgery to remove closed cranial sutures if skull pressure is high before six months of age. This allows the brain to grow without alleviate pressure and the skull bones to thicken so a definitive open cranial vault expansion can be performed.

Patients with syndromic craniosynostosis have a much greater risk for developing elevated pressure in the skull than non-syndromic craniosynostosis patients. These patients sometimes require an average of three or more skull surgeries. The major risk in young patients is blood loss because of their small size and small circulating blood volume. During most surgeries, these patients need blood transfusions.

At Children’s Health, we typically treat syndromic craniosynostosis patients with their first surgery between six months and one year of age. However, we operate earlier if there are multiple sutures causing elevated pressure on the brain.

Surgeries to treat syndromic craniosynostosis include:

• Open cranial vault remodeling

• Cranial vault distraction osteogenesis

• Fronto-orbital advancement (FOA)

• Strip craniectomy (suturectomy)