Craniosynostosis

Craniosynostosis are of several types; which include sagittal synostosis, frontal plagiocephaly and metopic synostosis. Signs and symptoms of craniosynostosis include the following:

• Shape of the head is unusual
• Increase in intracranial pressure
• Slow or no growth in the head size as the baby grows
• Affected sutures have a raised and hard ridge
• No fontanelle on the skull of newborn [8]

The following tests are employed for diagnosing craniosynostosis:

• Physical examination: A preliminary physical examination would be carried out to check for facial deformities and abnormalities in suture ridges.
• Imaging studies: Imaging studies such as CT scan of the head will be carried out to check whether any sutures will be fused or not. In addition, x-rays would also be done to measure the dimension of the baby’s skull.
• Genetic tests: This is done to identify the causative factor behind development of craniosynostosis. Such type of tests is done through blood tests to identify the type of genetic syndrome behind the condition. In many cases, hair, skin or other tissue of the baby may also be tested for any abnormality [9].

• Mild cases of craniosynostosis, require no treatment and abnormalities in the shape of the head become less evident as the baby grows. Helmet therapy may be recommended in such cases that would help reshape the head and in turn provide space for development of baby’s brain [10]. In other cases, surgery is the only resort to correct the deformity. The various types of surgical procedures that are involved include the following:
• Traditional surgery: In this type, an incision is made in the skull, and the affected portion is then reshaped with the help of plates and screws. In many cases, a second surgery may also be required, because there are chances of recurrence of craniosynostosis.
• Endoscopic surgery: It is a less invasive form of surgery, but is not meant for all cases of craniosynostosis. An endoscope is inserted through small incisions made in the skull, and the sutures are opened to provide room for brain development [11].

Children with no other associated underlying conditions do well after surgical intervention. Prognosis of craniosynostosis depends on the number of sutures involved and overall health condition of the child [6].
In case, when other associated anomalies are involved then the head deformity can be permanent, even if treatment is not initiated on time. Failure to initiate treatment on time can cause development of seizures, intracranial pressure and developmental delay [7].

The exact cause of craniosynostosis is unknown. However, the involvement of genes in the premature fusion of cranial sutures of the skull has been found to play foul [2]. Craniosynostosis is classified under 2 categories: nonsyndromic and syndromic. The cause of the former condition is unknown. In the latter type, genes and heredity are known to play foul. Genetic syndromes such as Crouzon syndrome, Apert syndrome and Pfeiffer syndrome are associated with abnormal skull development of the baby. In the year 1912, Crouzon was the first to describe heredity as the factor for development of craniosynostosis [3].

Craniosynostosis is estimated to occur in 1 in every 2000 live births globally. Complex craniosynotosis, wherein more than 1 suture is affected, is prevalent in 5 – 15% of the population. Occurrence of Apert syndrome and Pfeiffer syndrome is rare; whereas incidence of Coruzon syndrome has been recorded to be 1 in every 2,500 live births. About 40 – 55% of cases of craniosynostosis, is of the form sagittal synostosis [4].

Children with craniosynostosis, have abnormal osteoblactic activity along with increase osteocalcin levels, decrease in production of alkaline phosphatase and a decreased growth rate. In addition, affected children also have increases epidermal growth factor and platelet – derived growth factor.
New bone formation has been observed when resected sutures were histophatlogically examined. Such a phenomenon causes development of ridges in the affected area, which is palpable during clinical examination and is also evident during surgical procedure [5].

So far, no guidelines have been given to prevent craniosynostosis. However, there are certain small pieces of information suggesting that women who took adequate quantities of riboflavin, vitamin E, C and B6 were at a low risk of developing such anomalies than those who did not. Studies have suggested that, maternal nutrition has significant association with development of structural abnormalities. In view of this fact, it can be safely concluded that, consuming a nutritionally rich diet during the first trimester of pregnancy, can prevent the fetus from craniosynostosis.

This leads to significant change in the growth pattern of the skull. Craniosynostosis, in many cases is associated with underlying anomalies which may cause improper development of the brain. One or more joints may be affected by this condition and surgery is the only option to correct such a condition. If there is no underlying disease condition, then after surgery, the brain can develop appropriately [1].

• Definition: Craniosynostosis, is a condition, characterized by premature closing of sutures, which leads to improper shape of head. It is a birth defect, wherein the sutures close much before the brain gets fully developed. In this condition, one or more joints of the skull are affected.
• Cause: In many cases, the exact cause of craniosynostosis is unknown. Presence of underlying disease conditions is thought to play foul in development of certain forms of craniosynostosis. Certain type of genetic syndromes such as Apert syndrome, Coruzon syndrome and Pfeiffer syndrome can significantly affect the development of baby’s skull.
• Symptoms: Symptoms of craniosynostosis include development of unusual shape of head, slowed growth of head as the baby grows, increase in intracranial pressure and development of hard ridges in the affected area.
• Diagnosis: A preliminary physical examination will be carried out to determine abnormalities such as suture ridges and facial deformities. In addition, imaging studies such as CT scan and x-rays will also be required to determine fused sutures. Genetic testing also forms an essential part of diagnosis and is done to analyze the presence of genetic syndromes if any.
• Treatment: Mild cases of craniosynostosis seldom require any treatment if only one suture is involved and there are no underlying genetic abnormalities. In severe cases, surgery is the only available option to treat the condition.

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