| To help manage the molding that many newborns have as they go through the birth canal and then to deal with the brains rapid growth in the first years of life, the bones of an infant's skull are separated by the cranial sutures (sagittal, right and left coronal and lambdoid and the metopic suture) and fontanels (the soft spot). If one or more of these sutures close early (synostosis), it can lead to a condition called craniosynostosis, which can affect the shape of your child's head and face and if severe, can cause raised intracranial pressure (although this is uncommon in simple craniosynostosis, when only a single suture is closed).
It is usually not known what causes craniosynostosis. It is more common in males (especially with involvement of the sagittal suture) and occurs in about 1 of every 1-2000 births. Craniosynostosis, usually with more than one suture affected, is also commonly found in many syndromes, including Apert, Crouzon and Pfeiffer's syndrome.
Craniosynostosis can be either primary, from a problem with the involved suture, or it can also be secondary to slow brain growth, which can lead to a small head (microcephaly). Craniosynostosis is usually classified by which of the six sutures close early and the resulting head shape. Children with craniosynostosis have an abnormally shaped head, because when a suture closes early, the skull is forced to grow disproportionately in a different direction. It can also affect the appearance of the forehead, eyes and placement of the ears.
If both of the coronal or lambdoid sutures close early, it can lead to brachycephaly, with a skull that is short and wide. Premature closure of the sagittal suture (which is the most common type of craniosynostosis) can lead to dolichocephaly (also called scaphocephaly), small or absent anterior fontanels and a head shape that is long and narrow (keel shaped), as the skull is restricted from growing in width to the sides. Metopic synostosis can cause trigonocephaly or a triangularly shaped head and angular forehead.
Plagiocephaly (either anterior or posterior) occurs when one of the coronal or lambdoid sutures close early, leading to a head that is flat on one side and asymmetric. Infants commonly have positional posterior plagiocephaly from the position that they spend most of their time, either from lying on their back or because of congenital torticollis. Unlike plagiocephaly caused by premature closure of the lambdoid suture, children with positional plagiocephaly have open sutures.
Diagnosis of craniosynostosis is usually at birth or in early infancy, when a mishapened head is discovered. This is most easily noticed if the head is asymmetric or if there is ridging over the area of the affected suture. If the diagnosis isn't clear from the physical exam, or if multiple sutures are involved, then your Pediatrician may order testing with skull x-rays (although these don't always show fused sutures) or a CT scan (computed tomography) with bone windows vs. three-dimensional CT if available.
Some children with craniosynostosis, especially if multiple sutures are closed, can have symptoms of raised intracranial pressure. This can include vomiting, headache, irritability, lethargy, etc., but these symptoms are not commonly found.
Treatment depends on the timing of the diagnosis and which sutures are involved. While the timing of surgery is controversial, most doctors prefer to do surgery when the child is 3-6 months old. Older children (12-18 months) with a very mild deformity will probably not need surgery, while younger children with an obvious deformity that is moderate to severe will probably benefit from early surgery.
Treatment also depends on the type of craniosynostosis. Surgery (and there are many different types of surgery), especially if done early (by two to three months of age), may involve a simple removal of the affected suture (synostectomy), or (especially if done after 12 months of age) may require a craniectomy and reconstruction.
Most children with craniosynostosis (even if it involves only a single suture and is causing a mild deformity) should see a Pediatric Neurosurgeon and/or a Pediatric Craniofacial Plastic surgeon for evaluation and to discuss the need for treatment. If required, early treatment leads to the best results. You should discuss with your specialist whether or not surgery is required, which surgery is needed, and the timing of the surgery.
Internet Resources:
- Craniofacial Anomalies: includes a link to "A PICTORIAL guide to the anatomy and etiology of various types of craniosynostosis"
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