Craniosynostosis
Craniosynostosis is one of the disease groups within ERN CRANIO that covers a wide range of craniosynostosis, both unisutured and multisuture craniosynostosis fall under this group.
What is craniosynostosis?
Craniosynostosis is a condition in which one of more of the cranial sutures close too early. Cranial sutures are required for molding of the head during birth and for rapid growth of the skull in the first few years of life. Too early closure of suture(s) will results in an altered shape of the head and hamper normal growth of the brain.
Craniosynostosis occurs in 1 in 2100 to 1 in 2500 births and may be either non syndromic (also referred to as isolated) or syndromic.
ERN CRANIO endorses the European clinical practice guideline on craniosynostosis, created within the ERN CRANIO network. The guideline describes the treatment and management of craniosynostosis. A patient and family-tailored version of the professional guideline has been developed by one of the ERN CRANIO patient representatives.
Symptoms & consequences
The signs of craniosynostosis are usually noticeable at birth, but they'll become more apparent during the first few months of the baby’s life. Signs and severity depend on how many sutures are fused and when in brain development the fusion occurs. These can include:
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A misshapen skull, with the shape depending on which of the sutures are affected
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An abnormal feeling or disappearing fontanel on the baby's skull
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Development of a raised, hard ridge along affected sutures
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Slow or no growth of the head as the baby grows
Without treatment, the deformity of the skull will increase and there is a risk of high brain pressure. The chance of this differs per type of skull abnormality. It is also important to test the children for eye abnormalities, hearing
abnormalities, general development and breathing problems while sleeping.
Treatment & management
Treating craniosynostosis involves surgery to correct the shape of the head and allow for normal brain growth. Early diagnosis and treatment allows adequate space for the brain to grow and develop.
Centres of expertise for craniosynostosis
The hospitals below all have expertise in the field of unisuture/isolated craniosynostosis and/or syndromic forms of craniosynostosis. 'Having expertise" means that they have a national endorsement from their ministry of health, stating that they are an expert centre in the country. In addition, they meet the criteria for expertise of ERN CRANIO, which acknowledges them as 'European centres of expertise'
Unisuture craniosynostosis
With unisuture craniosynostosis, 1 of the sutures in the skull has closed prematurely, causing a change in skull shape. It is most often the only congenital disorder and is thus referred to as isolated.
Unilambdoid suture synostosis
The most common form of unilambdoid suture synostosis is non-syndromic.There is a slim chance of an inherited form of unilambdoid suture synostosis. There is also a slim chance that unilambdoid suture synostosis develops in a syndromic form. Individuals that do have a syndromic unilambdoid suture synostosis, develop the unilambdoid suture synostosis due to their other conditions or syndromes.
In lambdoid synostosis, growth of the skull base is also affected, indicated by the ear on that side being located at a lower position, best seen from behind. Moreover, backward growth of the occiput is inhibited on that side, which is accompanied by contralateral occipital bossing. Left lambdoid synostosis can also occur, when the lambdoid suture on the left side of the head closes prematurely. If the left occipital seam is closed then:
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The left ear is too low;
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The left side of the back of the head is lower;
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There is a crookedness in the face that is especially visible when you stand in front of the mirror with your child.
Sagittal suture synostosis
Sagittal suture synostosis can also called scaphocephaly. The most common form of sagittal suture synostosis is non-syndromic or 'isolated', because it's the only condition that your child may have and doesn't occur with any other conditions. There is a very slim chance of an inherited form of sagittal suture synostosis. There is a very slim chance that sagittal suture synostosis develops in a syndromic form. Individuals that do have a syndromic sagittal suture synostosis, develop the sagittal suture synostosis due to their other conditions or syndromes.
Because growth in width is inhibited, the skull grows more and more in length to compensate in the first year of life. The most common form of craniosynostosis is sagittal suture synostosis, where the sagittal suture, running in between the anterior and posterior fontanelle, closes prematurely. The forehead becomes rounder and the back of the head becomes more pointed. A bone ridge can often be felt at the location of the sagittal suture.
Metopic suture synostosis
Metopic suture synostosis can also called trigonocephaly. The most common form of metopic suture synostosis is non-syndromic. There is a very slim chance that metopic suture synostosis develops in a syndromic form. Individuals that do have a syndromic metopic suture synostosis, develop the metopic suture synostosis due to their other conditions or syndromes.
In children where the metopic or ' forehead' suture closes too early, the forehead cannot grow in width, but the rear part of the skull continues to grow. The forehead is therefore pointed, the eyes are close together and the outer corners of the eyes are higher than the inner corners. A bone ridge can often be felt at the location of the forehead seam. That is why we also call this condition 'wedge skull'. Only a severe wedge skull has these characteristics. A prominent vertical ridge over the metopic suture is palpated in the midline.
The condition can range from mild to severe. In contrast to the other types of craniosynostosis, the risk of increased cerebral pressure (which we determine through ophthalmology) in trigonocephaly is very low. That is why we are increasingly reluctant to operate. It also happens that the abnormal shape of the forehead improves spontaneously, so that surgery is no longer necessary as a matter of course
Unicoronal suture synostosis
Unilambdoid suture synostosis can also called plagiocephaly. The most common form of unicoronal suture synostosis is non-syndromic,and its cause is unknown. The chance exists that unicoronal suture synostosis is inherited by one of the parents. There is a slim chance that unicoronal suture synostosis develops in a syndromic form. Individuals that do have a syndromic unicoronal suture synostosis, develop the unicoronal suture synostosis due to their other conditions or syndromes.
In unicoronal synostosis, growth of the skull base is affected, indicated by the ear on that side being located at a lower position, best seen from behind. Moreover, backward growth of the occiput is inhibited on that side, which is accompanied by contralateral occipital bossing. Left unicoronal synostosis can also occur, when the coronal suture on the left side of the head closes prematurely.
If the left crown seam is closed:
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The left eye socket is too high
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Is the left side of the forehead towards the front;
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The eye opening is larger on the left than on the right
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the nose is slightly crooked.
Multisuture
craniosynostosis
In multisuture craniosynostosis, two or more cranial sutures have closed too early. Craniosynostosis is referred to as syndromic if other congenital disorders are present, such as disorders of the face, hands and feet, but may also involve other organs, for instance heart disorders or anorectal anomalies.
When two or more skull sutures close too early, the skull can no longer grow in that location. In a place where there is still space, the skull grows more. How many and which seams close too early determines what the shape of the skull looks like. Without proper treatment there is a high risk of high cerebral pressure. This causes the brain to work less well. In syndromic craniosynostosis, in addition to the closure of the cranial sutures, other congenital abnormalities also occur. For example, on the hands and feet, the eyes and eyelids, the upper jaw and teeth, the auricles and hearing.
Breathing can be somewhat difficult while sleeping, which causes snoring. We measure the severity of breathing problems with a sleep study.
Apert syndrome
The midface does not grow forward enough and the upper jaw is narrow, leaving little room for teeth and molars. The teeth often erupt late. Breathing may be difficult while sleeping, causing the child to snore or stop breathing for a short time. Ear infections occur more often. Severe acne can develop during puberty. Intelligence varies from normal to very low. Abnormalities that occur less often are: cleft palate, heart and kidney abnormality, and abnormalities of cervical vertebrae and joints.
Crouzon or Pfeiffer syndrome
Crouzon syndrome involves premature closure of the cranial sutures. The midface is set back and the eyes are far forward (“convex eyes”). Breathing is often audible while sleeping. The fontanel may feel tense.
In Crouzon syndrome, the skull shape can be abnormal or normal, depending on the cranial sutures involved. Brain abnormalities can include: high cerebral pressure, too much cerebrospinal fluid and too low position of parts of the cerebellum. The eye sockets are shallow, making the eyes more forward. The eyes may move abnormally because the muscles are not properly developed. The eye sockets may also be far apart.
The midface does not grow forward enough and the upper jaw is narrow, leaving little room for teeth and molars. The teeth often erupt late. Breathing may be difficult while sleeping, causing your child to snore or stop breathing for a short time. Ear infections occur more often. Average intelligence is normal but varies from low to high.
Muenke syndrome
Muenke syndrome is characterized by the premature closure of one (crooked forehead) or both coronal sutures (broad skull) and hearing loss.
Characteristics of this condition are:
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The skull shape is determined by the premature closure of one or both coronal sutures (crooked skull or wide skull)
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The mouth is small with a high and narrow palate. The upper jaw can be narrow, leaving little space for all the teeth.
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There is hearing loss due to a defect in the inner ear.
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Intelligence is almost normal.
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Behavioral abnormalities such as ADHD and autism-like disorders are more than twice as common as in peers.
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Breathing may be somewhat difficult while sleeping, causing the child to snore, for example. We measure the severity of breathing problems with a sleep study.
Craniofrontonasal syndrome
Too early closure of one or both coronal sutures (crooked or wide skull) and a wide nasal tip. The thumbs and big toes are broad or double. Often the chest is asymmetrical and there is a short neck.
Characteristics of this condition are:
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The skull shape is crooked or broad.
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The eyes may move abnormally because the muscles are not well developed. The eye sockets may also be far apart.
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The nasal tip is broad or split (dimple in the middle).
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The upper jaw is narrow, leaving little room for teeth and molars.
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The teeth often erupt late.
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The thumbs and big toes are broad or even double. The nails are often friable with ridges.
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The chest is skewed and the breast development can also be asymmetrical.
How often does it happen?
In the Netherlands, approximately one to two children per year are born with craniofrontonasal syndrome.
Saethre-Chotzen syndrome
The Saethre-Chotzen syndrome is characterized by premature closure of one (crooked forehead) or both coronal seams (wide skull) and the low hanging of one or both upper eyelids. The body length is short. The hands have webbed feet, one handline and short fingers.
The skull shape is determined by the premature closure of one or both coronal sutures (see crooked skull or wide skull). One or both upper eyelids hang too low and can obscure the pupil, making vision difficult. The upper jaw can be narrow, leaving little space for all the teeth. Less common abnormalities are: an abnormal location of the anus, umbilical hernia, cervical vertebral abnormalities, deafness, developmental delay. Breathing may be somewhat difficult while sleeping, causing the child to snore, for example. We measure the severity of breathing problems with a sleep study. The children may have a somewhat short body size.
TCF12 syndrome
Characteristic is the premature closure of one (crooked forehead) or both coronal sutures (broad skull). In exceptional cases, other cranial sutures may also have closed too early.
The skull shape is determined by the premature closure of one or both coronal sutures (see crooked skull or wide skull). The upper jaw can be narrow, leaving little space for all the teeth. Because the genetic abnormalities in the TCF12 gene have only recently been discovered, not much is known about the associated symptoms. Our team conducts scientific research into this.
Other syndromic
craniosynostosis syndromes
In other craniosynostosis syndromes, premature closure of two or more cranial sutures occurs, for which a genetic cause has been found. The syndrome is usually very rare or only recently known, so there is less information about it.
The premature closure of two or more cranial sutures determines the shape of the skull. Without proper treatment there is a high risk of excessive brain pressure. Other congenital abnormalities may also occur. We can increasingly find the genetic cause for this, but that is not always the case. To better recognize the cause, our team conducts a lot of research into this.