Apert syndrome is a rare genetic disorder that causes abnormal development of the skull. Babies with Apert syndrome are born with a distorted shape of the head and face. Many children with Apert syndrome also have other birth defects. Apert syndrome has no cure, but surgery can help correct some of the problems that result.
Causes of Apert Syndrome
Apert syndrome is caused by a rare mutation on a single gene. This mutated gene is normally responsible for guiding bones to join together at the right time during development. In almost all cases, the Apert syndrome gene mutation seems to be random. Only about one in 65,000 babies is born with Apert syndrome.
Apert Syndrome Symptoms
The defective gene in babies with Apert syndrome allows the skull bones to fuse together prematurely, a process called craniosynostosis. The brain continues to grow inside the abnormal skull, putting pressure on the bones in the skull and face.
The abnormal skull and facial growth in Apert syndrome produce its main signs and symptoms:
- A head that is long, with a high forehead
- Wide-set, bulging eyes, often with poorly-closing eyelids
- A sunken middle face
Other Apert syndrome symptoms also result from the abnormal skull growth:
- Poor intellectual development (in some children with Apert syndrome)
- Obstructive sleep apnea
- Repeated ear or sinus infections
- Hearing loss
- Crowded teeth due to underdevelopment of the jaw
Abnormal fusion of the bones of the hands and feet (syndactyly) -- with webbed or mitten-like hands or feet -- are also common Apert syndrome symptoms. Some children with Apert syndrome also have heart, gastrointestinal, or urinary system problems.
Apert Syndrome Diagnosis
Doctors often suspect Apert syndrome or another craniosynostosis syndrome at birth because of a newborn's appearance. Genetic testing can usually identify Apert syndrome or another cause of abnormal skull formation.
Apert Syndrome Treatments
Apert syndrome has no known cure. Surgery to correct the abnormal connections between bones is the main treatment for Apert syndrome.
In general, surgery for Apert syndrome takes place in three steps:
1. Release of skull bone fusion (craniosynostosis release). A surgeon separates the abnormally fused skull bones and partially rearranges some of them. This surgery is usually performed when a child is between ages 6 and 8 months.
2. Midface advancement. As the child with Apert syndrome grows, the facial bones again become misaligned. A surgeon cuts the bones in the jaw and cheeks and brings them forward into a more normal position. This surgery may be done at any time between ages 4 and 12. Additional corrective surgery may be needed, especially when midface advancement is done at a young age.
3. Correction of wide-set eyes (hypertelorism correction). A surgeon removes a wedge of bone in the skull between the eyes. The surgeon brings the eye sockets closer together, and may adjust the jaw, too.
Other Apert syndrome treatments include:
- Eyedrops during the day, with lubricating eye ointment at night; these drops can prevent the dangerous eye drying that can occur in Apert syndrome.
- Continuous positive airway pressure (CPAP); a child with Apert syndrome and obstructive sleep apnea may wear a mask at night, attached to a small machine. The machine delivers pressure that keeps the child's airways open during sleep.
- Antibiotics. Children with Apert syndrome are prone to ear and sinus infections caused by bacteria, requiring antibiotic therapy.
- Surgical tracheostomy, or placement of a breathing tube in the neck; this surgery may be done for children with severe obstructive sleep apnea due to Apert syndrome.
- Surgical placement of ear tubes (myringotomy), for children with repeated ear infections due to Apert syndrome
Other surgeries may be beneficial for certain children with Apert syndrome, depending on their individual pattern of facial bone formation problems.
Apert Syndrome Prognosis
Children with Apert syndrome usually require surgery for release of the skull bones to allow a chance for the brain to develop normally. The older a child is before this surgery is performed, the lower the chance for reaching normal intellectual ability. Even with early surgery, certain brain structures may remain poorly developed, however.
In general, children who are raised by their parents have a better chance of achieving normal intellectual ability. About four in 10 children with Apert syndrome who are raised in a healthy family environment reach a normal intelligence quotient (IQ). Among Apert syndrome children who are institutionalized, only about one in 18 achieves a normal IQ. In one study, three of 136 children with Apert syndrome eventually attended college.
Children with Apert syndrome and other similar conditions who have normal IQs do not seem to have an increased risk of behavioral or emotional problems. However, they may require additional social and emotional support to help cope with their condition. Children with Apert syndrome with lower IQs often do have behavioral and emotional problems.
There can be wide variability between children with Apert syndrome, with some severely affected, and others only mildly affected. Experts are unsure why the same gene mutation can result in such variation in a child's Apert syndrome prognosis.
Life expectancy also varies between children with Apert syndrome. Those with Apert syndrome who survive past childhood and don't have heart problems likely have a normal or near-normal life expectancy. Life expectancy is likely improving because of advances in surgical techniques and follow-up care.