Craniosynostosis
Your baby's skull may look solid, like that of a child or adult. But it is actually made up of separate bone plates that allow for the head to exit the mother's birth canal and for the rapid growth from birth through the first few years of your child's development. As your child grows, the plates move closer together until they meet at what are called suture lines, where the plates permanently close, usually between the ages of two and three years old.
Sometimes these bones grow together too soon, long before your baby's brain is fully formed, which can prevent the brain from growing properly. The head will also become misshapen and in some cases may cause your child's entire facial shape to change and become incorrectly formed.
If your baby's skull has closed too early, he or she may be referred for surgery. The neurologists and neurosurgeons here at Cook Children's are very experienced at this type of surgery. And because we are a pediatric health care system, we are also experts in kids. Our goal is separate the fused bones so that the brain and your child can grow to be their healthy best.
Craniosynostosis is a birth defect that affects the shape and growth of your baby's skull, and can sometimes impact the brain's growth and facial shape as well. There is actually more than one type of craniosynostosis, including:
- Sagittal synostosis (scaphocephaly) is the most common type. It affects the main suture on the very top of the head. The early closing forces the head to grow long and narrow, instead of wide. Babies with this type tend to have a broad forehead. It is more common in boys than girls.
- Frontal plagiocephaly is the next most common type. It affects the suture that runs from ear to ear on the top of the head. It is more common in girls.
Metopic synostosis is a rare form that affects the suture close to the forehead. The child's head shape may be described as trigonocephaly. It may range from mild to severe.
The cause of craniosynostosis is unknown. Genes may play a role. However, there is usually no family history of the condition.
One type that is passed down through families (inherited) can occur with other health problems, such as seizures, decreased intelligence, and blindness. Genetic disorders commonly linked to craniosynostosis include:
Apert syndrome
Apert syndrome is a genetic disorder characterized by the premature fusion of certain skull bones (craniosynostosis). This early fusion prevents the skull from growing normally and affects the shape of the head and face. In addition, a varied number of fingers and toes are fused together (syndactyly).
Many of the characteristic facial features of Apert syndrome result from the premature fusion of the skull bones. The head is unable to grow normally, which leads to a sunken appearance in the middle of the face, bulging and wide-set eyes, a beaked nose, and an underdeveloped upper jaw leading to crowded teeth and other dental problems. Shallow eye sockets can cause vision problems. Early fusion of the skull bones also affects the development of the brain, which can disrupt intellectual development. Cognitive abilities in people with Apert syndrome range from normal to mild or moderate intellectual disability.
Individuals with Apert syndrome have webbed or fused fingers and toes. The severity of the fusion varies; at a minimum, three digits on each hand and foot are fused together. In the most severe cases, all of the fingers and toes are fused. Less commonly, people with this condition may have extra fingers or toes (polydactyly). Additional signs and symptoms of Apert syndrome can include hearing loss, unusually heavy sweating (hyperhidrosis), oily skin with severe acne, patches of missing hair in the eyebrows, fusion of spinal bones in the neck (cervical vertebrae), and recurrent ear infections that may be associated with an opening in the roof of the mouth (a cleft palate).
Carpenter syndrome
Distinctive facial features may include a flat nasal bridge, outside corners of the eyes that point downward (down-slanting palpebral fissures), low-set and abnormally shaped ears, underdeveloped upper and lower jaws, and abnormal eye shape. Some affected individuals also have dental abnormalities including small primary (baby) teeth. Vision problems also frequently occur.
Abnormalities of the fingers and toes include fusion of the skin between two or more fingers or toes (cutaneous syndactyly), unusually short fingers or toes (brachydactyly), or extra fingers or toes (polydactyly). In Carpenter syndrome, cutaneous syndactyly is most common between the third (middle) and fourth (ring) fingers, and polydactyly frequently occurs next to the big or second toe or the fifth (pinky) finger.
People with Carpenter syndrome often have intellectual disability, which can range from mild to profound. However, some individuals with this condition have normal intelligence. The cause of intellectual disability is unknown, as the severity of craniosynostosis does not appear to be related to the severity of intellectual disability.
Other features of Carpenter syndrome include obesity that begins in childhood, a soft out-pouching around the belly-button (umbilical hernia), hearing loss, and heart defects. Additional skeletal abnormalities such as deformed hips, a rounded upper back that also curves to the side (kyphoscoliosis), and knees that are angled inward (genu valgum) frequently occur. Nearly all affected males have genital abnormalities, most frequently undescended testes (cryptorchidism).
A few people with Carpenter syndrome have organs or tissues within their chest and abdomen that are in mirror-image reversed positions. This abnormal placement may affect several internal organs (situs inversus); just the heart (dextrocardia), placing the heart on the right side of the body instead of on the left; or only the major (great) arteries of the heart, altering blood flow.
Saethre-Chotzen syndrome
Saethre-Chotzen syndrome is a genetic condition characterized by the premature fusion of certain skull bones (craniosynostosis). This early fusion prevents the skull from growing normally and affects the shape of the head and face.
Most people with Saethre-Chotzen syndrome have prematurely fused skull bones along the coronal suture, the growth line that goes over the head from ear to ear. Other parts of the skull may be malformed as well. These changes can result in an abnormally shaped head, a high forehead, a low frontal hairline, droopy eyelids (ptosis), widely spaced eyes, and a broad nasal bridge. One side of the face may appear noticeably different from the other (facial asymmetry). Most people with Saethre-Chotzen syndrome also have small, unusually shaped ears.
The signs and symptoms of Saethre-Chotzen syndrome vary widely, even among affected individuals in the same family. This condition can cause mild abnormalities of the hands and feet, such as fusion of the skin between the second and third fingers on each hand and a broad or duplicated first (big) toe. Delayed development and learning difficulties have been reported, although most people with this condition are of normal intelligence. Less common signs and symptoms of Saethre-Chotzen syndrome include short stature, abnormalities of the bones of the spine (the vertebra), hearing loss, and heart defects
Crouzon syndrome
Crouzon syndrome is a genetic disorder characterized by the premature fusion of certain skull bones (craniosynostosis). This early fusion prevents the skull from growing normally and affects the shape of the head and face.
Many features of Crouzon syndrome result from the premature fusion of the skull bones. Abnormal growth of these bones leads to wide-set, bulging eyes and vision problems caused by shallow eye sockets; eyes that do not point in the same direction (strabismus); a beaked nose; and an underdeveloped upper jaw. In addition, people with Crouzon syndrome may have dental problems and hearing loss, which is sometimes accompanied by narrow ear canals. A few people with Crouzon syndrome have an opening in the lip and the roof of the mouth (cleft lip and palate). The severity of these signs and symptoms varies among affected people. People with Crouzon syndrome are usually of normal intelligence.
Pfeiffer syndrome
Pfeiffer syndrome is a genetic disorder characterized by the premature fusion of certain skull bones (craniosynostosis). This early fusion prevents the skull from growing normally and affects the shape of the head and face. Pfeiffer syndrome also affects bones in the hands and feet.
Many of the characteristic facial features of Pfeiffer syndrome result from premature fusion of the skull bones. Abnormal growth of these bones leads to bulging and wide-set eyes, a high forehead, an underdeveloped upper jaw, and a beaked nose. More than half of all children with Pfeiffer syndrome have hearing loss; dental problems are also common.
In people with Pfeiffer syndrome, the thumbs and first (big) toes are wide and bend away from the other digits. Unusually short fingers and toes (brachydactyly) are also common, and there may be some webbing or fusion between the digits (syndactyly).
Pfeiffer syndrome is divided into three subtypes. Type 1, also known as classic Pfeiffer syndrome, has symptoms as described above. Most individuals with type 1 Pfeiffer syndrome have normal intelligence and a normal life span. Types 2 and 3 are more severe forms of Pfeiffer syndrome that often involve problems with the nervous system. The premature fusion of skull bones can limit brain growth, leading to delayed development and other neurological problems. Type 2 is distinguished from type 3 by the presence of a cloverleaf-shaped head, which is caused by more extensive fusion of bones in the skull.
While these conditions are quite serious, it is important to note that most children with craniosynostosis are treatable and otherwise healthy and have normal intelligence.
Symptoms depend on the type of craniosynostosis. They may include:
- No "soft spot" (fontanelle) on your newborn's skull
- A raised hard ridge along the affected sutures
- Unusual head shape
- Slow or no increase in the head size over time as the baby grows
- You think your child's head shape is unusual
- Your child is not growing well
- Unusual raised ridges on your baby's scalp
During your baby's exam, the doctor will take a complete medical history, including a family history, perform a physical exam, and feel your baby's head for any abnormalities such as ridges or facial abnormalities. In addition, the following tests may be done:
Because craniosynostosis is not always obvious at birth (many babies have misshapen heads temporarily due to their arrival through the birth canal, well-child visits are an important part of your child's health care. During these visits your doctor or nurse regularly checks the growth of your baby's head over time. If there is a problem, it can be identified early and can help to prevent many long-term issues.
Not all babies require surgery. Those with extremely mild cases will become less obvious as your baby grows. Some children may also benefit from a cranial helmet, which can help to reshape the head without surgery. However, for most infants, surgery is recommended and may be the only treatment option. Surgery is typically done while your baby is still an infant, though not always. They type and timing of your child's surgery will depend on the type of craniosynostosis and her or his symptoms. The goals of surgery are:
- Relieve any pressure on the brain
- Make sure there is enough room in the skull to allow the brain to properly grow
- Improve the appearance of the child's head
Your child's surgery team at Cook Children's will consist of a neurosurgeon (a doctor who specializes in brain surgery) and a craniofacial surgeon (a doctor who specializes in surgery of the head and face). The procedure will typically be one of two types of surgery:
- Traditional surgery which involves an incision in your child's scalp and cranial bones. The surgeon then reshapes part of the skull.
- Endoscopic surgery is less invasive and is used whenever possible. This type of surgery is faster, and usually means a shorter stay in the hospital and, in many cases, a faster recovery time.
As scary as the idea of surgery seems, especially on your tiny baby, Craniosynostosis results in head deformity that can be severe and permanent if it is not corrected. Increased intracranial pressure, seizures, and developmental delay can occur. Treating your baby early means the best possible outcome now and especially in the future.
We're here to help.
If your child has been diagnosed, you probably have lots of questions. We can help. If you would like to schedule an appointment, refer a patient or speak to our staff, please call our offices at 682-303-2650.