Craniosynostosis is a medical condition where an infant’s skull bones join together prematurely. This early fusion can alter the normal shape of a baby’s head and potentially impact brain growth. It is a congenital birth defect.
Understanding Craniosynostosis
A newborn’s skull consists of several separate bony plates connected by flexible, fibrous joints called sutures. These sutures allow the skull to expand as the baby’s brain grows during the first few years of life. In craniosynostosis, one or more of these sutures fuse too early, restricting the skull’s ability to grow uniformly.
The specific head shape that develops depends on which suture or sutures fuse prematurely. Sagittal craniosynostosis, the most common type, involves the suture running along the top of the head, resulting in a long, narrow head shape. Coronal craniosynostosis, affecting the suture from ear to ear, can cause a flattened forehead and brow on the affected side. If both coronal sutures fuse, the head may appear short and wide.
Metopic craniosynostosis, involving the suture from the top of the head down the middle of the forehead, can lead to a triangular forehead shape. Lambdoid craniosynostosis, occurring at the suture along the back of the head, results in a flattening of the back of the head. The sutures usually remain open until around age three, allowing for brain growth, with complete fusion occurring later in the teen years.
Recognizing the Signs
The most noticeable sign of craniosynostosis is an abnormal head shape. A baby’s head might appear elongated, pointed, or flattened in certain areas, becoming more apparent as the infant grows.
A distinct ridge along the prematurely fused suture may also be felt on the baby’s scalp. The soft spot, or fontanelle, on the top of the head might feel smaller than expected or even absent. A lack of growth in the baby’s head circumference can indicate restricted skull expansion.
Diagnosis and Causes
Craniosynostosis is often diagnosed through a physical examination. If concerns arise, imaging tests such as X-rays or computed tomography (CT) scans are used to confirm the diagnosis by visualizing the fused sutures.
In many cases, craniosynostosis occurs as isolated (non-syndromic) craniosynostosis, where the reason for early fusion is unknown. This form is not associated with other health issues. However, craniosynostosis can also be part of syndromic craniosynostosis, linked to specific genetic conditions such as Apert syndrome, Crouzon syndrome, or Pfeiffer syndrome. These genetic syndromes often involve other physical characteristics or developmental differences.
Treatment and Long-Term Outlook
The primary treatment for craniosynostosis is surgical intervention, often before one year of age. The main goals of surgery are to correct the abnormal skull shape and to create sufficient space for the brain to grow properly. Surgical approaches can vary; for younger infants, endoscopic surgery may be an option, while open cranial vault remodeling is often performed for older infants.
If craniosynostosis is left untreated, complications can arise from restricted skull growth. The most significant concern is increased intracranial pressure, which occurs when the growing brain has insufficient room. This elevated pressure can lead to symptoms such as headaches, nausea, vomiting, and can affect brain tissue and limit brain development. Untreated craniosynostosis can also result in developmental delays, vision problems, and cosmetic deformities of the head and face.
With timely and appropriate surgical treatment, the long-term outlook for children with craniosynostosis is positive. Post-surgery, consistent follow-up care is important to monitor the child’s development and skull growth. While some children may require ongoing support, especially if developmental delays or other syndromic features are present, early correction of the skull shape often allows for normal brain development and a good quality of life.