There are different types of craniosynostosis, depending upon which of the sutures close too early. Craniosynostosis can be simple (one suture closes early) or complex (more than one suture closes early). Children born with craniosynostosis have a unique appearance. The exact shape of the skull is determined by which sutures close prematurely. As the sutures close, growth of the skull usually occurs in the opposite direction to make room for brain growth. With this information doctors can usually tell which suture or sutures are closed based on the shape of the head.
It is important to differentiate between positional skull deformation (also called “positional molding”) and craniosynostosis. Positional deformation is very common and occurs from babies reclining in one position for long periods of time, typically on their backs. It can result in the back of the head being flat or, if the baby prefers to turn the head to one side, being crooked in the back. Some babies also will develop asymmetry of the face or ears as well. Positional molding is a non-surgical condition that can be corrected with less invasive procedures such as repositioning the baby, “tummy time,” stretching exercises, alternate seating, and sometimes helmets. Positional molding usually improves by itself once babies are rolling and sitting. In contrast, true craniosynostosis gets worse over time and requires surgical intervention. Your provider or specialist knows how to tell the difference between these conditions.
The different types of craniosynostosis include the following:
- Sagittal synostosis, the most common type, happens when the suture along the top of the head fuses together. This causes the head to look narrower as well as longer from front to back.
- Metopic synostosis happens when the suture in the center of the forehead fuses before birth. It causes a triangle-shaped forehead and narrow face. However, many babies with normally-shaped foreheads can develop a ridge (bump) on their heads after birth. This can be normal. The ridge smoothes out over time. If you are concerned, your baby’s care team can tell the difference.
- Coronal synostosis is when one or both of the sutures on the side of the head fuse. It causes one side of the forehead and face to look different from the other. If it affects both sides of the head, the forehead can look tall and flat when looking at the baby from the side.
- Lambdoid synostosis is very rare. It is when one or both of the sutures in the back fuse. This can cause the back of the head to have an abnormal shape. Sometimes, it can also make the back of your baby’s head look flat. Your doctor can tell if the flat spot is caused by lamdoid synostosis or by your baby laying on his/her back. An imaging study, like an X-ray, can also help tell the difference.
This webpage is intended to provide health information so that you can be better informed. It is not a substitute for medical advice and should not be used to treatment of any medical conditions.