Isolated (Non-Syndromic) Craniosynostosis: Sagittal Synostosis
Sagittal suture craniosynostosis (scaphocephaly) is the most common form of isolated craniosynostosis. Patients with this pattern of suture closure make up about half of all craniosynostosis cases. All skull bone growth occurs perpendicular or growing away from the suture. The sagittal suture runs lengthwise along the top of the skull from front to back, therefore the growth at this suture gives the skull its width.
When the sagittal suture is closed the skull can’t widen, so the remaining open sutures must create more bone to make room for the growing brain. The orientation of the remaining open sutures – the coronal, lambdoid and metopic sutures – can only create bone perpendicular to their axis. The lack of bone growth at the sagittal suture and extra bone growth at the remaining open sutures makes the head longer and narrower than usual. In some children, there is more fullness (bossing) of the forehead. In others, the back of the head may be more significantly affected with a longer, narrow and coned shape. In some patients, the changes in shape may be even distributed from front to back. Boys tend to have this type of craniosynostosis more than girls with a ratio of 4 boys to each girl with this defect.
There is no one operation that works well for all patients. In general, the treatment strategy depends on the age of the patients at the time of diagnosis. If the patient is between birth to 4 months, a limited incision extended strip craniectomy with helmet is performed. If the patients presents from age 4 months or older, then an open cranial vault remodeling is performed. There are many approaches to open cranial vault remodeling in sagittal synostosis. In general, the skull bones are removed in the areas of abnormal restricted and compensatory growth and repositioned to over correct the head shape and increase the space in the skull. In general, for sagittal suture craniosynostosis the surgeries are aimed at restoring normal dimensions in the width, height and length of the skull. Rarely, surgeons use cranial vault distraction.