What is Syndromic Craniosynostosis?
Craniosynostosis is the premature fusion of one of the cranial sutures, which results in restricted head growth and an abnormal head shape. Most cases involve a single suture and have no other abnormalities. Cases of syndromic craniosynostosis have a clear genetic cause, have other associated abnormalities, and commonly involve multiple sutures. The most common pattern of suture fusion in syndromic craniosynostosis is bilateral fusion of the coronal suture. This causes a short, and tall skull.
What Causes Syndromic Craniosynostosis?
Each of the syndromes associated with craniosynostosis is caused by an altered gene. These can be inherited from a parent or can occur spontaneously in a patient. We have yet to identify the genetic cause of every case of syndromic craniosynostosis, but researchers continue to find new genes. Our geneticist will evaluate your child and order appropriate tests to help you identify the cause of his or her condition.
What are the symptoms of syndromic craniosynostosis?
Patients with syndromic craniosynostosis and multiple fused sutures are more likely to develop increased pressure in their skull due to restriction of head growth. This can cause headaches, developmental delay, seizures, and vision loss. This is much more common in patients with premature fusion of multiple sutures.
Signs and symptoms of increased intracranial pressure include:
- Vision changes
- A full or bulging fontanelle (soft spot)
- Increased sleepiness
- Noticeable scalp veins
- Increased irritability
- Poor feeding
- Increased head circumference
- Bulging eyes or inability to look upward
- Developmental delay
These symptoms are not specific signs of increased intracranial pressure and may be caused by many medical conditions. Your pediatrician should be contacted if you have any concerns.
Patients with significant midface hypoplasia resulting from their condition may develop exposure and irritation of the eyes. This condition may also cause significant airway obstruction and obstructive sleep apnea (OSA). Patients often have dental anomalies that require expert care of a pediatric dentist and orthodontist.
Apert syndrome is associated with the most severe extremity abnormalities. These patients have fusion of the bones and soft tissues of the fingers and toes, which result in complex syndactyly or a “mitten hand.” Other syndromes have less severe extremity abnormalities, such as the wide thumbs and great toes of Pfeiffer syndrome.
How are Patients with Syndromic Craniosynostosis Evaluated?
Patients with syndromic craniosynostosis require evaluation by a team of specialists including a pediatric plastic surgeon, pediatric neurosurgeon, a pediatric ophthalmologist, a pediatric ENT specialist, a pediatrician, a geneticist, a pediatric dentist, an orthodontists, an audiologist, and a speech therapist.
Your surgeon’s will likely order imaging studies to examine the bones of the skull and brain. These studies will likely include a CT scan and/or an MRI. Regular eye exams are important to look for signs of increased intracranial pressure. If you child develops symptoms of sleep apnea, the doctors will likely have an overnight sleep study or polysomnogram to measure the disorder.
How are Patients with Syndromic Craniosynostosis Treated?
Patients with syndromic craniosynostosis require surgery to expand the skull and relieve pressure from the brain. These procedures are performed by a pediatric plastic surgeon and a pediatric neurosurgeon. The surgeons will discuss the surgical options with you and select the best procedure for your child. Procedures used to treat this condition include minimally invasive sutuectomy with helmet therapy, posterior cranial distraction osteogenesis, calvarial vault remodeling, and a fronto-orbital advancement. Children with syndromic craniosynostosis may require two or more procedures before they are fully-grown. Some children require an additional procedure to place a shunt to drain cerebrospinal fluid and relieve elevations in intracranial pressure.
Patients with significant midface hypoplasia will require surgery to advance their midface. This helps to better protect the eyes, treats obstructive sleep apnea, and improves the ability of the teeth to come together. This procedure is commonly done using the technique of distraction osteogenesis. The bones of the face are gradually advanced after surgery. Some patients will require an external distractor or “halo.” Others can be treated with internal distractor devices that are buried under the skin. Your surgeon may elect to treat your child with different procedures including a Le Fort III osteotomy, monobloc osteotomy, or facial bipartition osteotomy. Your surgeon will discuss these procedures with you to select the best operation for your child. Midface advancement is commonly done after a child is 7-8 years old. Delaying surgery decreases the chances it will need to be repeated.
Many patients require orthognathic surgery (corrective jaw surgery) when they are finished growing to fix how their teeth fit together and improve their breathing and appearance. Commonly patients require a Le Fort I osteotomy to advance the upper jaw. Some patients would also benefit from an operation of the lower jaw to allow further advancement. Prior to surgery, your child will require 1-2 years of braces to improve the alignment of the teeth. Their orthodontist will usually continue braces for 6 months after surgery to fine-tune the alignment of the teeth. Patients must wear their retainers after surgery to prevent the teeth from shifting and compromising their outcome.
Patients with complex extremity deformities may require reconstructive surgery for these. Our plastic and orthopedic hand specialists will assist with evaluating and treating these conditions.