Craniosynostosis

Congenital myasthenic syndromes are typically identified at birth. But if signs and symptoms are mild, the condition may not be identified until childhood, or rarely, early adulthood.

Depending on the type of congenital myasthenic syndrome, the severity of signs and symptoms vary greatly, from minor weakness to the inability to move. Some symptoms can be life-threatening.

Common to all congenital myasthenic syndromes is muscle weakness that worsens with physical activity. Any muscles used for movement can be affected, but the most commonly affected muscles are those that control movement of the eyelids and eyes and chewing and swallowing.

During infancy and early childhood, progressive loss of essential voluntary muscle activity occurs with muscle use. Impaired muscle weakness can result in:

• Droopy eyelids and poor eye control, often with double vision.
• Difficulty chewing and swallowing.
• Weakness of facial muscles.
• Weak cry.
• Slurring or nasal speech.
• Delayed crawling and walking.
• Delayed development of wrist, hand and finger skills, such as brushing teeth or combing hair.
• Trouble supporting the head in an upright position.
• Problems breathing, such as feeling short of breath and having short pauses in breathing, sometimes worsened by infection, fever or stress.

Depending on the type of congenital myasthenic syndrome, other signs and symptoms can include:

• Skeletal deformities, such as joint, spine or foot deformities.
• Unusual facial features, such as narrow jaw or wide-set eyes.
• Hearing loss.
• Weakness, numbness and pain, usually in hands and feet.
• Seizures.
• Kidney problems.
• Cognitive impairment, rarely.

On the top of the head toward the front, some sutures meet at the large soft spot called the anterior fontanel. The anterior fontanel is the soft spot felt just behind a baby’s forehead. The next largest fontanel, called the posterior fontanel, is at the back of the head where the other sutures meet. The flexible, fibrous sutures connect the bony plates of the skull.

The term given to each type of craniosynostosis depends on which sutures are affected. Types of craniosynostosis include:

• Sagittal. The sagittal suture runs from front to back at the top of the skull between the front and back fontanels. When the sagittal suture closes too early, it forces the head to grow long and narrow. Sagittal craniosynostosis is the most common type of craniosynostosis.
• Coronal. Coronal sutures run from each ear to the top of the skull, meeting at the front fontanel. When only one coronal suture closes too early, it may cause the forehead to flatten on that side and bulge on the other side. It also causes the nose to turn and the eye socket to rise on the affected side. When both coronal sutures close too early, the head looks short and wide, often with the forehead tilted forward.
• Metopic. The metopic suture runs up from the top of the bridge of the nose through the middle of the forehead to the front fontanel. When the metopic suture closes too early, the forehead has a triangular shape and the back part of the head widens.
• Lambdoid. The lambdoid suture runs down the back of the head from the back fontanel. When the lambdoid suture closes too early, it may cause one side of a baby’s head to appear flat, one ear to be higher than the other ear and the top of the head to tilt to one side. Early closing of the lambdoid suture is a very rare type of craniosynostosis.

Other reasons for a changed head shape

A head shape that’s not typical doesn’t always mean that a baby has craniosynostosis. For example, if the back of your baby’s head appears flattened, it could be the result of spending too much time lying on the back. This can be treated with regular position changes. If the head is very flat on one side, helmet therapy can help reshape the head to a more balanced look.

Your pediatrician or other healthcare professional monitors your child’s head growth at well-child visits. Talk with your healthcare professional if you have concerns about your baby’s head growth or shape.

Often the cause of craniosynostosis is not known. But sometimes it’s related to genetic conditions.

• Nonsyndromic craniosynostosis is the most common type. Its cause is not known, but it’s thought to be a mix of genetic and environmental factors.
• Syndromic craniosynostosis is caused by certain gene changes that cause genetic syndromes. Examples include Apert syndrome, Pfeiffer syndrome and Crouzon syndrome. These syndromes can affect a baby’s skull development. They usually also include other physical changes and health conditions.

Genetic syndromes that affect a baby’s skull development, such as Apert syndrome, Pfeiffer syndrome and Crouzon syndrome, are risk factors for craniosynostosis.

If not treated, craniosynostosis may cause:

• Lasting changes in the shape of the head and face.
• A feeling of not being worthy and of wanting to stay away from others.

The risk of higher pressure inside the skull, called intracranial pressure, from craniosynostosis is small if the suture and head shape are treated with surgery. Babies who have craniosynostosis caused by a genetic syndrome may develop higher pressure inside the skull if treatment doesn’t make the skull larger to make room for their growing brains.

If not treated, higher pressure inside the skull can cause:

• Developmental delays.
• Problems with thinking, memory and learning.
• Blindness.
• Seizures.
• Headaches.

Sometimes a pediatrician may suspect craniosynostosis at a routine well-baby visit. Or you may make an appointment because you have concerns about your baby’s head growth. Your healthcare professional can refer you to a specialist for diagnosis and treatment.

Here’s some information to help you get ready for your appointment. If possible, take a family member or friend with you. That person can help you remember information and give emotional support.

What you can do

Before the appointment, make a list of:

• Any symptoms you’ve noticed, such as raised ridges or a change in the shape of your baby’s face or head.
• Questions to ask your healthcare professional.

Questions to ask might include:

• What’s the most likely cause of my baby’s symptoms? Are there other possible causes?
• What kinds of tests does my baby need? Do we need to do anything to get ready for these tests?
• What treatments are available? Which do you suggest?
• Are there other treatment options?
• What are the risks with surgery?
• Who will do the surgery if it’s needed?
• What happens if we choose not to have the surgery right now?
• Will the shape of the skull affect my baby’s brain?
• What are the risks that future children will have the same condition?
• Are there brochures or other printed material that I can have? What websites do you suggest?

Feel free to ask other questions during the appointment.

What to expect from your doctor

Your healthcare professional is likely to ask you questions, such as:

• When did you first notice the changes in your baby’s head shape?
• How much time does your baby spend lying on the back?
• In what position does your baby sleep?
• Is your baby’s development like that of other children of the same age?
• Were there any complications during your pregnancy?
• Do you have a family history of craniosynostosis or genetic conditions such as Apert syndrome, Pfeiffer syndrome or Crouzon syndrome?