Craniosynostosis: what it is, symptoms, causes and treatment

Great Ormond Street Hospital (GOSH) explains that the skull is made up of several plates of bone which, at birth, are not tightly joined together. The seams where the plates join are called sutures, and as we grow older they gradually fuse, usually after all head growth has finished. In craniosynostosis the sutures fuse before birth. It can affect one suture (simple or single suture craniosynostosis) or several (complex craniosynostosis), which may happen as part of a syndrome.

Alder Hey Children's Hospital says this fusion can cause problems with brain and skull growth, and in some cases developmental delay, especially if more than one suture is involved. Some children develop raised pressure inside the skull (intracranial pressure), and how often this happens depends on which sutures are involved.

The NHS says your baby may have a problem like craniosynostosis if any of the following apply. If the problem is mild, it may not be noticeable until your child is older.

• Their head is long and narrow, like a rugby ball.

• Their forehead is pointy or triangular.

• One side of their head is flattened or bulging out.

• The soft spot on the top of their head (fontanelle) disappears before they are 1 year old.

• Rarely, there may be learning difficulties, sight or hearing loss, breathing problems such as not being able to breathe through the mouth, or dental problems.

The NHS says to see a GP if you are concerned about the development of your child's head in terms of its shape and size, or if your baby or child has symptoms of craniosynostosis and seems to have problems with their vision or hearing, has speech problems or is slow to start talking, or has difficulty breathing normally through the mouth, which can lead to snoring and sleep problems at night.

The GP will examine your child's head and may take measurements to see if it is an unusual size for their age. If they think your child could have craniosynostosis, they may refer them to a specialist centre for more tests such as X-rays or scans. Alder Hey says babies should be referred as soon as an abnormality of head shape is suspected, which may even be at birth.

The type depends on which suture is affected. The NHS lists five main types, and Alder Hey adds that the most common is scaphocephaly (sagittal), occurring in 1 in 2,500 to 5,000 children.

The NHS says syndromic craniosynostosis is caused by an underlying genetic condition. GOSH lists syndromes it treats, including Apert, Crouzon, Pfeiffer, Muenke and Saethre-Chotzen syndromes, and says new genetic forms have been identified. For single-suture craniosynostosis, the sources reviewed do not give a single cause, and Alder Hey says some children see a clinical geneticist to discuss the diagnosis and arrange further tests.

The NHS says it is normal for a baby's head to be a slightly unusual shape and that this will often get better as they grow. Alder Hey explains that flattening at the back of the head is much more commonly related to a benign condition from the way a baby sleeps, known as deformational plagiocephaly, which does not require surgery. Lambdoid synostosis, by contrast, is extremely rare.

Because the two can look similar, the GP or specialist team examines the head and, if needed, arranges X-rays or scans to tell them apart.

The NHS says if your baby has craniosynostosis they will have regular check-ups to monitor it, and treatment usually involves surgery. The type of treatment depends on the type of craniosynostosis, your baby's symptoms and their age. Some cases may just be monitored and not need treatment.

Surgery usually involves making a cut across the top of the head, removing and reshaping the affected parts of the skull and fixing them back in place, under general anaesthetic. The NHS says your child may need to stay in hospital for up to a week afterwards. In some cases, a less invasive endoscopic procedure, passing a thin flexible tube through a small incision in the skull, may be possible, followed by wearing a specially designed helmet.

Alder Hey describes the timing at its unit. For sagittal (scaphocephaly) craniosynostosis, an early operation below 6 months, either endoscopic strip craniectomy with helmet therapy for at least 12 months or a passive vault operation, or a larger operation between 18 and 24 months. For trigonocephaly and unicoronal synostosis, early endoscopic surgery below 6 months or larger remodelling at 18 to 24 months, and for lambdoid synostosis, remodelling of the back of the head at 18 to 24 months. For multiple sutures, a specialist team assesses the benefits and risks of surgery.

The NHS says many children do not have any lasting health problems from craniosynostosis. They may have a scar across the top of the head if they had surgery, but this is hidden by hair. Check-ups may be every few weeks at first and become less frequent as they get older. If a child has certain types, surgery cannot always fully correct the shape of the head and they may need ongoing care.

Depending on symptoms, the NHS says a child may also need regular hearing and eye tests, speech and language therapy, specialist dental treatment, psychological counselling or further surgery as an older child or teenager. Alder Hey says children with craniosynostosis receive speech and language and neurodevelopmental assessments at set points in childhood, and that in children with non-syndromic single suture craniosynostosis speech and language delay can be as common as 40%, compared with 6 to 10% in the general population.

Craniosynostosis care in England is concentrated in four supra-regional centres: Great Ormond Street, Alder Hey, Birmingham Children's Hospital and the John Radcliffe Hospital in Oxford. A multidisciplinary team usually includes surgeons, geneticists, speech and language therapists, psychologists, orthodontists and eye and ENT specialists. Alder Hey says children can move to adult services at 16 with the same team of surgeons.

The NHS and Alder Hey point families to Headlines, the UK craniofacial support charity, for information and support.

Craniosynostosis is assessed and treated through specialist NHS centres, with referral from a GP, health visitor or hospital paediatrician. Because there are only four centres, families often travel, and the centres coordinate care with local services for hearing, vision and development.

Private craniofacial assessment is available for some families. The surgical techniques are the same, and it is sensible to make sure the team is part of a multidisciplinary craniofacial service and that your GP and the NHS centre are kept informed.