Craniosynostosis is a condition in which the bones of the skull fuse together prematurely. Our skulls are not made up of one single bone. Rather, several different bones fit together to make up the skull. The areas where the bones meet one another are called "sutures". As a baby grows, the brain rapidly increases in size. The growing brain pushes on the bones of the skull, causing the skull bones to expand and grow. When one of these sutures closes or is fused too early, growth is restricted. This growth restriction in one area may lead to overgrowth in other areas as the growing brain tries to get more room. This process results in an abnormally shaped skull. The altered head shapes occur in a rather predictable fashion and diagnosis can frequently be made simply based on a proper physical examination and we encourage the first consultation as early as feasible. Scaphocephaly, plagiocephaly and trigonocephaly are the most common medical terms used to describe these head shapes. Craniosynostosis most commonly affects single sutures, as described here. In less common situations, craniosynostosis may also affect multiple sutures and lead to a more complex scenario. These have names such as Crouzon syndrome, Apert syndrome, Pfeiffer syndrome, Saethre-Chotzen syndrome and others.
In plagiocephaly, the forehead of the baby is flat on one side and the eyes may appear to be different sizes. "Plagiocephaly", from the Greek meaning "flat head", can be a confusing term because it does not necessarily result from craniosynostosis. Any asymmetric flattening of the forehead or back of the head should be examined by an experienced craniofacial plastic surgeon, neurosurgeon or neurologist so that deformational plagiocephaly can be differentiated from true craniosynostosis. True craniosynostosis requires surgery for correction, while deformational plagiocephaly, if addressed early enough, will very rarely require surgery. Neck position is also frequently an area of concern and eye muscles may also be out of alignment. We recommend that the consultation be performed so that treatment can be coordinated properly..
Premature fusion of the sagittal suture results in scaphocephaly. "Scaphocephaly" is the medical term that describes a head that is elongated front to back and narrow from ear to ear. The sagittal suture runs front to back, along the middle of the top of the head. A ridge may be felt along the fused suture. It is premature closure of this sagittal suture that causes a long, narrow skull.
There are several techniques available for the correction of scaphocephaly. The goal of treatment is to achieve a more normal shape which consists of shortening the skull front to back and making it wider from side to side, and to allow more normal growth. No single technique appears to be the best one for every patient. The decision is based upon the findings of a face-to-face consultation. Surgery may include what is called a Calvarial Vault Remodeling (CVR) or an "endoscopic" approach.
"Plagiocephaly" results when one of the coronal sutures fuses prematurely. The coronal sutures travel across the top of the skull. The soft spot (fontanel) is located between the right and left coronal sutures, but may be closed because of the synostosis. When viewed from above, the forehead on the affected side is flat and recessed when compared to the other side, which may bulge further forward than normal. This happens to compensate for the brain's inability to grow on the flat side. The fused suture prevents forward growth of the brain on the flat side. Looking at the child's face, the brow on the affected side is usually higher than the other side making that eye appear larger, and the tip of the nose may appear to be deviated to the other side. Plagiocephaly is estimated to occur in about one in 3,500 births.
"Trigonocephaly" is caused by fusion of the metopic (forehead) suture. This suture runs from the top of the head down the middle of the forehead, toward the nose. Early closure of this suture may result in a prominent ridge running down the forehead. Sometimes, the forehead looks quite pointed, like a triangle, with closely placed eyes ("hypotelorism"). It is very important to note the pinching of the temporal areas that results from the synostosis. In these cases, the ridge, the pointed forehead and the temporal pinching all need to be addressed. Trigonocephaly can also result from treatment of bilateral retinoblastoma with radiation in childhood although the head shape is noted later.