Craniosynostosis

CRANIOSYNOSTOSIS

Craniosynostosis occurs when a baby’s skull bones fuse too early before 2 years
of age and causes problems with the shape of the baby’s skull. This restricts the
growth of the brain. With early treatment, most children don’t experience any
other craniosynostosis symptoms. Babies may undergo helmet therapy or
surgery to correct the skull shape.

 

 

Overview

What is craniosynostosis?

A newborn baby’s skull consists of several bones that fit together. Usually,
newborns have spaces called sutures between their skull bones. The sutures let
the skull size grow to accommodate the baby’s growing brain. When the bones
of the skull are fused together either at birth or fuse too soon, the condition is
called craniosynostosis.

The sutures of the skull fuse around the brain at around age 2 years. When a
baby has craniosynostosis, one or more of these sutures hardens too early and
closes before the baby reaches age 2.

How does craniosynostosis affect the body?

In places where sutures have fused too early, a baby’s head may stop growing.
In other areas, where sutures haven’t fused, the baby’s head will continue to
grow. As a result, babies with craniosynostosis often have heads that are
asymmetrical (misshapen).

If a baby has multiple sutures that close too early, the brain might not have
enough room to grow. As a result, these babies might experience a buildup of
pressure in the skull (intracranial pressure).

What are the types of craniosynostosis?

Craniosynostosis types are based on where the sutures close:

• Sagittal craniosynostosis affects the suture on the top of the head.
Babies with sagittal craniosynostosis often have a long, narrow head
(scaphocephaly).

• Coronal craniosynostosis affects one of the coronal sutures, which run
from both ears to the top of the head. Babies with this type may have a
flat forehead and a broad head.

• Lambdoid craniosynostosis affects the suture along the back of the
head. Babies with this type often have a flat back of the head
(Plagiocephaly)

• Metopic craniosynostosis affects the suture that runs from the top of the
nose to the top of the forehead. Babies with this type may have a
triangular head, with the narrow ridge at the midline of the forehead.

How common is craniosynostosis?

Craniosynostosis is uncommon. It affects about 1 in every 2,500 babies in the
United States.

Sagittal craniosynostosis is the most common type of congenital
craniosynostosis.

Symptoms and Causes

What causes craniosynostosis?

In most babies, experts can’t identify one known cause of craniosynostosis.
Sometimes, craniosynostosis occurs because of a sporadic (random) gene
mutation (change), or it may run in families. Prematurity is a risk factor for
craniosynostosis.

In other cases, some factors during pregnancy increase a baby’s risk for
developing craniosynostosis. These include:

• Fertility medications such as clomiphene citrate (Clomid®).
• Maternal thyroid disease (developing thyroid disease while pregnant).

What are the symptoms and signs of craniosynostosis?

The primary symptom of craniosynostosis is a misshapen skull. If babies
receive early surgical treatment such as Endoscopic release or MicroSurgery
with release of the fuse sutures they may not experience any other
craniosynostosis symptoms.

Other signs of craniosynostosis include:

• No fontanelle (soft spot) on a baby’s head where the skull hasn’t closed.
• Small, hard ridge of bone that can be felt on the baby’s head.
• Face that looks uneven or asymmetrical.

What are the complications of craniosynostosis?

If left untreated, craniosynostosis or the resulting intracranial pressure can lead
to:

• Developmental Delays and Seizures.
• Vision or eye movement disorders, such as strabismus (crossed eyes)or
other disorders.
• Breathing difficulties, especially if associated with other bony
abnormalities of the face.
• Persistent head or facial deformities.

Some children may struggle with self-esteem and body image if they have facial
asymmetry or deformities. Support groups, counseling and psychotherapy can
help your child a positive self image.

Diagnosis and Tests

How is craniosynostosis diagnosed?

Neurosurgeons and Pediatricians usually can diagnose craniosynostosis by
feeling for soft spots on your baby’s head, feeling for ridges that signify fused
skull sutures and measuring the head circumference.

If the size of your baby’s head is not growing as expected, the healthcare
provider will check for craniosynostosis. It’s important to remember that a
small-sized head can be due to several other reasons as well. Your baby may
need an X-ray , CT scan , MRI of the head and brain to confirm this diagnosis.

Management and Treatment

How is craniosynostosis treated?

Craniosynostosis treatment varies depending on the severity and the baby’s
symptoms. Treatment may include:

• Helmet therapy: Babies with mild craniosynostosis may wear a special
medical helmet. This helmet gently reshapes the skull over time.
• Surgery: Many babies need head surgery by a Neurosurgeon to release
the fused sutures and reshape the skull thus relieveing increased
intracranial pressure and allowing the baby’s brain room to grow and
develop properly. The Neurosurgeon determines the timing of the surgery
depending on the severity of the condition and the symptoms associated.
Babies might need surgery within the first year of life. Endoscopic
surgery could be used before 6 months of age in selected patients to
release the craniosynostosis without open surgery says Dr Prem Pillay a
Neurosurgeon who was trained at the Hospital for Sick Children, Toronto
and the Cleveland Clinic; and now practises at Mt Elizabeth Hospital in
Singapore.

Your child may need other supportive therapies such a physical, occupational
and speech therapies to support return to normal functioning and activities.

Prevention

How can I prevent craniosynostosis?

There is no guaranteed way to prevent craniosynostosis. Prenatal genetic testing
may show gene mutations that could lead to craniosynostosis. A genetic
counselor can help you understand genetic risks and possible treatment options
if your baby is born with craniosynostosis.

You can increase your chances of having a healthy baby by:

• Scheduling regular prenatal visits.
• Speaking with your doctor about potential risk factors, including risks
associated with fertility medications or thyroid disease.
• Taking prenatal supplements or other supplements as directed.

Outlook / Prognosis

What is the outlook for babies with craniosynostosis?

Most babies who receive timely craniosynostosis treatment live a healthy life.
Earlier treatment can minimize developmental problems due to pressure on the
brain.

What conditions are related to craniosynostosis?

Some babies with craniosynostosis also have a genetic syndrome. Some genetic
syndromes that can cause a misshapen skull and other associated abnormalities
include:

• Apert syndrome.
• Carpenter syndrome.
• Crouzon syndrome.
• Pfeiffer syndrome.
• Saethre-Chotzen syndrome.

References

1. The Cleveland Clinic Foundation, Dept of Neurosurgery and Children’s
hospital.
2. Protocols of the Singapore Brain Spine Nerves Center, Mt Elizabeth
Medical Center, Singapore (Contact: brainspinesg@gmail.com)