Common difficulties seen in children with Sturge Weber Syndrome

About 60 per cent of children with SWS have delayed developmental milestones. That is, they do not develop and acquire key skills at the same age as children without SWS. This means that:

- They may have delayed language skills, this may be the way they use language or the way the understand language, or both.

- They may have delayed fine motor skills, the way they use their hands and coordinate vision with this

- They may have delayed gross motor skills, the way they use their body to move.

- They may think and learn differently. This may affect their ability match their peers in the school environment.

These issues tend to happen more in children who experience epilepsy with SWS. These difficulties may carry on through life and may be better defined at Intellectual disability or specific learning needs when older.

Children may have associated developmental problems such as an autistic spectrum disorder or attention deficit hyperactivity disorder (ADHD).

However, children vary enormously and so children with SWS can have abilities within the normal range or have more delayed development. Children with abnormal blood vessels on both sides of the brain are more likely to have more severe learning disabilities than those where it involves only one side of the brain.

Cognitive impairment (developmental delay and intellectual disability) are commonly seen in individuals with SWS. About two thirds of children show difficulties that mean that they would struggle at school without educational support and have difficulties with some of their self-care skills at home. However, not everyone has an intellectual disability and those who do will vary substantially with respect to the severity of the impairment that they have.

The more frequent and severe the seizures the child has and the greater the extent of blood vessel abnormality across the brain, the more learning tends to be affected. Research has suggested that intellectual disability is associated the presentation of epilepsy that the child has (earlier seizure onset, more frequent status epilepticus and seizure clusters) and also with the distribution of blood vessels in the brain (more lobes with angioma). The difficulties are often long term.

Not all children with Sturge Weber Syndrome have difficulties acquiring language skills. However, seizure activity is associated with language delay and disorder. Language skills are more likely to be impacted in a child who experiences early, severe seizure activity and the risk of difficulties lessens if seizures start later on and are less severe. This is because an older child has had a chance to lay down the language pathways in their brain. There are three parts to speech and language skills that can be impacted by SWS/epilepsy:

Receptive Language – a child’s understanding of another person’s language

Expressive Language – a child’s ability to use language and find the right words to express themselves

Speech sounds/articulation – a child’s ability to use the right speech sounds in every word. Stammering has also been reported but not fully researched at this point.

We talk about language delay in younger children and language disorder in. older ones.

Autism is a neurodevelopmental condition that causes differences in social awareness, social communication, sensory sensitivity and repetitive or stereotyped behaviours. Autism has been found to be associated with SWS with about one quarter of people having a diagnosis of autism and just under half having more broader difficulties and differences with social communication skills. The degree of impairment suffered is variable and research has found that children with SWS actually have a relative strength in social awareness and motivation to engage with others (which are usually much reduced in people with autism). This may explain why autism is often overlooked in this population.

Children may have other associated developmental problems such as attention difficulties.

Hypermobility

Joint hypermobility is commonly seen in children with SWS; this can vary greatly in severity although most commonly this is mild and doesn’t significantly impact your child’s mobility and independence. Someone can be described as having hypermobility when they are more flexible than the average person. It can occur in one joint or in a number of joints and can range in severity. Hypermobility may be caused by a number of reasons:

The shape of the bones e.g. a shallow hip socket which will allow more movement

Low muscle tone (Hypotonia) :This means that the muscles are more relaxed around the joint and can therefore stretch further. In infants with low muscle tone, this can lead to gross motor delay although this again varies depending on severity. A made to measure dynamic garment called Lycra may be helpful to some children who experience motor delays and postural instability as a result of hypotonia.

If the ligaments that surround and provide stability for joints are more lax than usual. Many people even without SWS will have hypermobility without any problems.

However in some individuals it can lead to painful joints particularly after high impact sports which may involve lots of running and/or jumping. This may also cause your child to fatigue more easily when exercising and in some cases make your child more prone to trips/falls particularly during the first years of life. In infants/toddlers this might cause some delay with attaining motor milestones more typically walking, running, jumping and balancing on one leg.

As a result joint hypermobility can have an effect on hobbies and school. However there are things that you can do to help. Hypermobile joints will be flexible throughout a person’s life therefore it is important that strategies are in place to manage this if it is causing pain.

Please refer to hypermobility leaflet for additional information on management.

Further reading

http://www.patient.co.uk/support/Hypermobility-Syndrome-Association.htm

http://www.nhs.uk/Conditions/Joint-hypermobility/Pages/Symptoms.aspx

http://www.nhs.uk/conditions/Joint-hypermobility/Pages/Introduction.aspx

http://www.hypermobility.org/

http://www.livestrong.com/article/148640-exercises-for-hip-hypermobility/

Limb Hypertrophy (limb overgrowth)

Some individuals may present with limb overgrowth (hypertrophy) most typically of one of the lower limbs more so than upper limbs.

Hypertrophy of the affected extremity is commonly due to underlying soft tissue or adipose tissue hyperplasia and lymphoedema. Rarely, it may be associated with bony hypertrophy that can lead to a limb-length discrepancy.

In this instance a shoe insert may be recommended depending on the severity of this; in some rare cases where the limb length discrepancy is caused by bony overgrowth orthopaedic monitoring during growth and/ or intervention later in life may be required.

Macrocephaly

Additional symptoms seen in children with SWS may occur including an abnormally large head (macrocephaly).In young infants this may cause some delays with achieving head control and floor mobility.

Movement disorders: Hemiplegia and Quadriplegia

Children with SWS might have a weakness and or muscle stiffness in the opposite side of the body to the port wine stain due to abnormal blood vessels in the brain. They may also have difficulty using the affected side because they are less aware of it. The degree of weakness varies from child to child and may be barely noticeable or more obvious. Some infants/children may have a limb weakness of one side as they are developing. More commonly, a weakness occurs with seizures, particularly if these are difficult to control. This can leave the child with a permanent weakness affecting balance and attainment of motor skills to varying degrees although some improvement often occurs over a period of several months. A transient (short-lived) weakness lasting a few hours may occur in association with headaches. Your child may require physiotherapy or Occupational therapy intervention depending on the extent of motor/functional deficit. Some children may require specialist equipment and/or orthotics such as hand or foot splints to maintain joint flexibility and promote independence.

The most affected children with bilateral involvement may develop muscle weakness and or stiffness affecting all four limbs as the result of severe seizures; in some cases postural asymmetries can develop with time and orthopaedic monitoring hips and or spine may be required as the child grows.

Physiotherapy and occupational therapy will be more involved locally to provide specialist equipment and therapeutic interventions to help archive’s your child’s best potential. If your child develops increased muscle stiffness which impacts on their function he/she may benefit from a referral to a more specialist movement disorder service by your paediatrician to assess and advice on tone management interventions.

Visual field deficit

Some children with SWS have a visual field deficit. This means that they have trouble seeing objects in part of their field of vision. In infants, this can be diagnosed by clinical examination, but diagnostic assessment is more difficult until children are of primary school age and can understand how to cooperate with the assessment. Ophthalmologists can also arrange a test to assess the visual pathway that may indicate if there is a visual field deficit.

Once you know which side is affected, you can make sure that toys, games or work are put within your child’s field of vision. Children with a visual field deficit may seem to use the hand on the affected side less than the other, so ways of improving this might be suggested.

Glaucoma

Another feature of SWS is glaucoma. Glaucoma is raised pressure within the eye, which can lead to blindness if it is not treated. Glaucoma is diagnosed using a test that measures intraocular pressure (IOP) by blowing a puff of air into each eye.

The majority of children develop glaucoma in infancy, but some do not develop it until later childhood. The specialist eye doctor (ophthalmologist) should examine your child’s eyes to check for glaucoma regularly: at least every year for the first five years, and then every two years. If your child develops glaucoma, they will need more frequent appointments.