The conditions we most commonly see are single suture synostosis, Aperts, Crouzons, Saethre-Chotzen and Pfeiffers syndrome. We also see children with hemifacial microsomias, midfacial clefts, facial morphea and post-radiotherapy facial deformity.
Single suture synostosis
Children with this condition have relatively few functional problems. Children with unicoronal synostosis (fusing together of the coronal suture) may require assessment by an ophthalmologist as they are more likely to get a squint on the affected side.
There is a small percentage of children with sagittal synostosis who have some delay in speech and language development and may need some help with this.
There is also a very small percentage of children with metopic synostosis who can have some general developmental delay. Metopic synostosis can also be linked if the mother has been taking sodium valproate (an anti-epileptic drug) during pregnancy. Other causes of isolated metopic synostosis are not known at present.
The skull is not a single bone like a crash helmet but is made up of 'plates' of bone that are joined together by seams (sutures) similar to what you might find in clothing.
The sutures are there to help with the moulding of the head during delivery but they also have a role in the general shaping of the head as it grows. They are not in fact essential for head growth – the head will grow even when all the sutures have fused together but if there is a problem with them then the shape of the head can be affected.
The premature closure of a single skull vault suture occurs weeks or months before a child is born. In most circumstances, the cause for it is unknown. It usually has no implications with regard to brain pressure/distortion and decisions concerning surgical treatment need to be made on cosmetic grounds.
It is rare that cases of single suture synostosis are associated with raised intracranial pressure as the more complex forms of craniosynostosis can be. Without surgical intervention the head shape is likely to remain much as it is – it will continue to grow but with similar proportions as now.
Sometimes, there is a slight tendency for the degree of asymmetry to become a little more pronounced over the years but there is no guarantee that this is going to happen.
Surgical intervention
Surgical intervention carries an excellent chance of restoring a more normal contour to the head although it is perhaps unrealistic to expect absolute perfection. However, it is usually possible to achieve a very marked improvement in head shape.
Over the following years there is sometimes a slight tendency for the original head shape to reassert itself but it is unusual for this to be to a degree that requires any further surgery.
The timing of the surgery varies depending upon which suture is involved. For children with sagittal synostosis there is an operation that can be performed at around the age of five or six months. This involves the removal of the fused suture, combined with a manoeuvre designed to shorten the length of the head from front to back while widening it from side to side.
For children who, for some reason or another, are not operated upon at this early age, there are still procedures that can be carried out later but they involve a more extensive reconstruction of all or, at least, the front half of the head.
For children with premature fusion of either one coronal suture (which typically produces flattening of one side of the forehead and bulging of the other) or with metopic synostosis (which gives a triangular shape to the front of the head), surgery, in our experience, is best carried out when a child is 15 to 18 months old – or even older than this.
This choice of the optimal age for surgery is different to what some craniofacial surgeons choose but in our experience it means that there is less chance of the child’s head shape reverting to something like its original appearance over the years to come.
All of the operations involved in treating single suture synostosis are major and therefore have particular dangers. The dangers for any operation are usually related to some unexpected event such as bleeding, infection or an anaesthetic complication.
Most children are out of hospital in three to five days and no particular post-operative precautions are required at home.
Children may have a degree of swelling of the forehead and eyelids following the surgery although we now use a particular technique during the surgery to try and keep this to a minimum.
Follow-up usually consists of a hospital clinic visit six to eight weeks after the operation and then further reviews at one year and at three years later. We like to undertake a long follow-up like this because of our interest in the continuing progress of children we have treated for craniosynostosis.
Parents of children with craniosynostosis affecting a single skull vault suture often ask us if the condition will crop up again in subsequent pregnancies. Our Geneticists usually quote an incidence of approximately 2 per cent for this – a figure that makes it still very unlikely although 1:50 is a higher incidence than for the general population.
We hope that these notes are helpful. Please do not hesitate to let us know if there are further questions that you would like answered.
New surgical technique for craniosynostosis
The surgical procedure for children who have a sagittal synostosis and are ideally under six months has changed over the past year. Our Consultant Neurosurgeon has developed a lesser procedure using stainless steel springs to achieve the desired change in skull shape. This operation entails one or possibly two smaller cuts over the top of the head, two bone cuts to free the fused suture and then placement of the springs.
Over the coming weeks the springs expand slowly and the skull gradually remoulds to the desired shape. Once this has been achieved, the springs are then removed under a short general anaesthetic.
The main advantages of this technique is that it is a smaller operation and the postoperative recovery is a lot shorter. The disadvantage is that a further operation is required (usually a daycase) to remove the springs.
For children who are six to eight months plus, the traditional operation that involves a cut across the top of the head, like an Alice band that a little girl would wear, is still carried out.
Complex syndromic craniosynostosis
Children referred to us with more complex conditions after intial consultation are brought into the hospital for a three to four day period for assessment. The child and family get to meet all members of the team over this period of time. They receive a CT scan, sleep study, eye, hearing, speech and feeding assessments; a developmental review and ear, nose and throat and a genetic review.
At the end of the period of assessment the family meet the craniofacial consultants on the ward and a plan of care management is discussed. During this time the family take to each appointment with them, a dictaphone (small tape recorder).
Each team member dictates their findings and recommendations onto this and a full and comprehensive summary is then typed up the following week and sent out to the family, GP, Paediatrician and anyone else involved in their care. This ensures that information is detailed and collected together in one report, being sent out within a week of the actual assessment.
For children with syndromes such as Apert, Crouzon, Saethre-Chotzen or Pfeiffers these assessments are then carried out at intervals during the early years of their lives to ensure that any functional problems associated with their condition are picked up and therefore addressed early.
These children and their families also receive shared care records to take home. This helps to improve communication between local and central services and to provide families with a comprehensive "set of notes" and information at their fingertips.
The skull is not a single bone like a crash helmet but is made up of 'plates' of bone that are joined together by seams (sutures) similar to what you might find in clothing.
The sutures are there to help with the moulding of the head during delivery but they also have a role in the general shaping of the head as it grows. They are not in fact essential for head growth – the head will grow even when all the sutures have fused together but if there is a problem with them then the shape of the head can be affected.
Sutures normally fuse after all head growth has finished. However, they can sometimes fuse before birth and this is the condition known as craniosynostosis. It may affect a single suture or several. When it affects a single suture it is often referred to as 'simple' craniosynostosis.
When it affects multiple sutures then it is often associated with a particular syndrome (in other words, the child may have other parts of the body – particularly the facial bones and fingers – affected as well). It may affect a single suture or several.
Syndromic and the other complex forms of craniosynostosis usually involve the two coronal sutures which run from the anterior fontanelle region down the side of the head to the temple area. When these fuse prematurely, they produce a flattening of the forehead which is particularly obvious where it meets the upper border of the eye sockets.
Sometimes only the two coronal sutures are involved, sometimes all the sutures of the skull are affected.
In addition to changing the child’s appearance, complex forms of synostosis can be associated with several other problems. If the bones of the upper jaw fail to grow forward normally, this produces obstruction to the child’s airway that can lead to difficulty breathing.
If the bones both above and below the eye sockets have failed to grow properly, the eyes themselves may be left in a protruding position and when this is severe the child may have difficulty closing his or her eyes.
Another possible complication for children with complex syndromic forms of craniosynostosis is raised pressure inside the head (raised intracranial pressure – ICP). This can be due to several different causes. The bones of the skull may just not be able to expand sufficiently to accommodate the growing brain and there is therefore a mismatch between the size of the brain and the bone of the skull that can lead to a rise in ICP.
Some children also have obstruction to the flow of 'brain water' (cerebrospinal fluid – CSF) which normally circulates through various cavities (the ventricles) within the brain and then over the surface of the brain. Obstruction to the circulation leads to a build-up of CSF under pressure – a condition we call hydrocephalus. Finally, raised ICP can be due to obstruction of the veins of the head as they pass through the bones at the base of the skull (venous hypertension).
As you can see, children with complex and syndromic forms of craniosynostosis may have little wrong with them except for a change in their appearance, but some are much more severely affected and have problems related to eye exposure, difficulty breathing and raised intracranial pressure.
It is for this reason that it is our usual policy to admit these children to our unit for a few days of formal assessment that may include brain scanning (usually computerised tomographic – CT) and examination by a variety of different specialists including ophthalmology (eyes), ear, nose and throat, orthodontics (teeth), plastic surgery, genetics, speech and language, and psychology – and any other specialties that appear appropriate.
This assessment allows the craniofacial team to decide whether the child has any problems that require immediate attention (raised intracranial pressure or difficulty breathing for example) or, if all is well at present, what sort of future supervision by the craniofacial team is required. Most children who do not require any early form of intervention are then looked after according to a protocol that determines how often they are seen and at what intervals further assessments are required.
Our general policy with regard to the management of children with complex and syndromic forms of craniosynostosis can be summarised as follows:
Most of these conditions are caused by a single, disordered gene (see section on genetics below) that continues to exert its effects upon the growth of the head and face for as long as growth continues – often up until the late teenage years. This means that if any form of reconstruction is carried out before growth has ended, subsequent growth will tend to produce a degree of relapse (or reversion) of whatever has been achieved by the operation.
From this it can be seen that unless surgery is required for some pressing functional reason (difficulty breathing, raised ICP, for example), the best final cosmetic result may not be achievable until the child is nearly grown up. Once again, this depends very much upon the severity with which the child has been affected and the syndrome involved (some have comparatively minor effects, some more major).
During a child’s early years therefore, we tend to reserve surgical intervention for such problems as raised intracranial pressure, difficulty breathing, eye exposure etc. The timing of surgery for ‘purely’ cosmetic reasons varies from child to child and from syndrome to syndrome.
The earlier such surgery is carried out, the more likely it is that either all or some element of it may need to be repeated. However, children who look unusual may be bullied at school and therefore there are often compelling reasons for operating earlier (just prior to a change of school, for example).
Here is a brief description of the syndromes we most commonly encounter:
Crouzon syndrome
There is premature closure of both coronal sutures but in more severe cases, other skull sutures may be involved as well.
There is failure to grow forward of the upper jaw and cheekbones and the nose may have a ‘beaked’ appearance. There is a large variation in the extent to which children may be affected, ranging from very mild with few complications and normal development, to children who require frequent surgical interventions.
Apert syndrome
Premature closure of at least both coronal sutures and recession of the upper jaw and cheekbones produces a characteristic facial appearance with a tendency for the outer part of each eye to slope downwards.
The characteristic feature of Apert syndrome is that the children are born with their fingers and toes matted together (syndactyly). Learning difficulties (developmental delay) is common, as are problems with breathing (airway obstruction) and, in severe cases, raised intracranial pressure.
Pfeiffer syndrome
There is (at least) premature closure of both coronal sutures together with impaired development of the upper jaw and cheekbones.
In addition, children with Pfeiffer syndrome have a characteristic appearance of their thumbs and big toes – they tend to be broad and slightly apart from the other toes. The most severely affected children with Pfeiffer syndrome have hydrocephalus and an abnormal head shape that can take on a clover-leaf appearance.
Saethre-Chotzen syndrome
Both coronal sutures fuse early but the effect can often be asymmetrical. The nose may be rather prominent but abnormal development of the upper jaw and cheekbones is uncommon as is raised intracranial pressure.
A characteristic feature is often drooping of one or both eyelids (ptosis). A minor abnormality of one or more fingers is often seen.
Muenke (P250A) syndrome
This syndrome has only been described since the advent of DNA testing. It causes premature closure of a single coronal suture or sometimes both. In either case it is entirely compatible with normal intellectual development although some children do have learning difficulties.
Facial problems, airway obstruction and eye exposure do not usually occur in this syndrome. In other words, its implications tend to be entirely cosmetic.
Cranio-fronto-nasal displasia
In this syndrome there is a characteristically wide separation between the eyes (hypertelorism). There is usually premature fusion of one coronal suture. Other features include a prominent gap between the two front teeth and 'unruly hair'.
It is rare for it to be associated with eye exposure, airway obstruction, raised intracranial pressure or any other facial deformity. Treatment is therefore only required for cosmetic reasons.
Genetics
All the conditions listed above are due to a particular disordered gene and can be inherited/passed on in a distribution that is termed 'autosomal dominant'. This means that if one parent is affected, half his or her children (and all these conditions can affect boys as well as girls) are likely to be affected also.
Many of these conditions however occur in children whose parents are not obviously affected. In this situation the gene mutation is a new one and most geneticists assess the risk of the same parents having a similarly affected child as approximately 2 per cent (as opposed to the 50 per cent if one parent is already affected).
Positional plagiocepahly
The current remit of the four centres does not include the management of positional plagiocephaly. We do have information leaflets available on the condition that include guidelines on repositioning techniques etc for families.
Surgery
Surgery for children with a single suture synostosis is undertaken at different ages depending on the condition.
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Sagittal synostosis: four to six months is the ideal age for this surgery to be performed as the procedure is much simpler and of a lesser nature at this age. That is not too say that if your child is not referred until they are well over this age that surgery cannot be performed. It can be performed at any age but four to six months would be the preferred timing.
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Unicoronal synostosis: around 15 to 18 months
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Metopic synostosis: around 12 to 15 months
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Lamboid synostosis: this is rare as an isolated condition and often more associated with the complex children who have more than one suture fused together.
Surgery for the more complex children initially depends on any functional problems. These are problems that may occur in the early weeks, months and years of the child's life. They may be problems with raised pressure in the head that might require head surgery to 'make more room'.
Other problems might be with their breathing and they may need a tracheostomy tube or nasal tube (prong) to help them breath more easily. Surgery to change the child's appearance for aesthetic reasons is best left until they are much older, when facial bone growth is slowing down or has stopped ie adolescence.
This may not always be possible, especially if the child is struggling with their appearance or being bullied and regular assessment will address the 'right' time for midfacial surgery. This will all be discussed with you and your consultant at various appointments and assessments to determine when the best time might be.
The RED frame (distraction surgery)
If the decision has been made for your child to have midface surgery, either for functional reasons, such as pressure on the brain, eye problems or breathing problems, or because this is what they have chosen, then distraction is usually the surgery of choice. It is a gradual process of moving already separated bone in the face and forehead, forward.
The children wear a half halo frame on their heads for a period of about three months. It is a major procedure to undergo and both you and your child are given a lot of preparation and support.
We have found that the children, even the toddlers, have tolerated it very well and it has been very effective in achieving both functional improvement as well as a cosmetic effect that both child and family have found to be very positive.
There are some cases where the more traditional midface surgery is appropriate where bone grafts are used to keep the face in a forward position. The options about which surgery is best depends on a number of things, such as how far forward the midface needs to move to achieve the required result, and these options and the reasons for them would always be discussed with you and where appropriate, your child, before a procedure was undertaken.
Our surgery days are every Monday all day and the first Wednesday of the month all day.
We see a varying amount of conditions from children who have been born with a single suture (or seam) fused to those with a genetic craniofacial condition such as Apert, Crouzon, Saethre-Chotzen or Pfeiffers.
We also see children who have acquired facial anomalies ie through trauma or following treatments for cancer (post radiotherapy treatment).
Other conditions we see are
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Treacher-Collins
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Goldenhar/hemifacial microsomia
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Craniofronto-nasal dysplasia
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Encephalocele
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Facial clefts (children with isolated cleft lip and/or palate are seen here by the cleft lip and palate team)
