Sagittal synostosis is a type of craniosynostosis, a condition where skull sutures close too early. This premature fusion of the sagittal suture, which runs from the front to the back along the top of the head, is a relatively rare birth defect. Early identification of this condition is important for appropriate medical intervention.
Understanding Sagittal Synostosis
A newborn’s skull has flexible sutures that allow the brain to grow rapidly. These sutures typically remain open until late in the teenage years, accommodating the brain’s expansion. In sagittal synostosis, the sagittal suture prematurely fuses, preventing normal growth perpendicular to this suture. This early closure forces the skull to grow in an abnormal direction, specifically becoming elongated from front to back and narrow from side to side. This characteristic head shape is often referred to as “scaphocephaly,” derived from the Greek word for “boat-shaped”. The condition typically affects more males than females.
Recognizing the Signs
The most noticeable sign of sagittal synostosis is an abnormal head shape, which is usually apparent at birth or becomes more pronounced within the first few months. The head appears unusually long and narrow when viewed from the top. This elongation is often accompanied by a prominent forehead and a noticeable bulging at the back of the head. Parents or caregivers might also observe a raised bony ridge along the top of the baby’s head, directly over the fused sagittal suture. The skull may feel narrow across the sides, particularly in the bitemporal and biparietal regions. If any of these visual cues are observed, consulting a pediatrician for further evaluation is advisable.
Diagnosis and Potential Causes
Diagnosis typically involves a physical examination, which includes palpating the suture lines on the infant’s skull. During this examination, the absence of movement between the two bones adjacent to the sagittal suture can indicate fusion. A thickened ridge over the affected suture is also a common finding. To confirm the diagnosis and assess the extent of the fusion, imaging studies are often utilized. A quick and painless X-ray of the head can show the fused suture, but a CT scan provides more precise detail, revealing the bony structure and confirming the premature closure. In most instances of isolated sagittal synostosis, the underlying cause remains unknown, appearing sporadically without a clear genetic link. However, in very rare cases, craniosynostosis can be part of a broader genetic syndrome, although sagittal synostosis is typically non-syndromic.
Treatment Approaches and Outcomes
The primary treatment for sagittal synostosis is surgical intervention, with the goal of correcting the abnormal head shape and allowing for proper brain growth. Surgery is typically performed within the first year of life, often before six months of age, to achieve the best outcomes. There are different surgical techniques available, including traditional open cranial vault reconstruction and minimally invasive endoscopic surgery. Traditional open surgery involves a larger incision to reshape the skull and release the fused suture. Minimally invasive endoscopic surgery is an option for younger infants, typically performed before five or six months of age, and involves smaller incisions with the assistance of an endoscope to release the fused suture. Following successful surgical correction, the expected outcomes generally include significant cosmetic improvement in head shape. Neurodevelopmental outcomes are typically favorable when the condition is treated, as the surgery alleviates any potential pressure on the growing brain. Post-operative follow-up care is important to monitor the child’s cranial growth and overall development.