Paediatric Neurology

Question 1

Syncope

Answer 1

Syncope is the term used to describe the event of temporarily losing consciousness due to a disruption of blood flow to the brain, often leading to a fall. Syncopal episodes are also known as vasovagal episodes, or simply fainting.

A vasovagal episode (or attack) is caused by a problem with the autonomic nervous system regulating blood flow to the brain. When the vagus nerve receives a strong stimulus, such as an emotional event, painful sensation or change in temperature it can stimulate the parasympathetic nervous system. Parasympathetic activation counteracts the sympathetic nervous system, which keeps the smooth muscles in blood vessels constricted. As the blood vessels delivering blood to the brain relax, the blood pressure in the cerebral circulation drops, leading to hypoperfusion of brain tissue. This causes the patient to lose consciousness and “faint”.

Question 2

Signs and symptoms of syncope

Answer 2

Patients often remember the event and can recall how they felt prior to fainting. This is called the prodrome, and involves feeling:

Hot or clammy
Sweaty
Heavy
Dizzy or lightheaded
Vision going blurry or dark
Headache
A collateral history from someone that witnessed the event is essential to get an accurate impression of what happened. During a vasovagal episode they may describe the person:

Suddenly losing consciousness and falling to the ground
Unconscious on the ground for a few seconds to a minute as blood returns to their brain
There may be some twitching, shaking or convulsion activity, which can be confused with a seizure
The patient may be a bit groggy following a faint, however this is different from the postictal period that follows a seizure. Postictal patients have a prolonged period of confusion, drowsiness, irritability and disorientation.

There may be incontinence with both seizures and syncopal episodes.

Question 3

Causes of syncope

Answer 3

When assessing someone presenting with a syncopal episode the key is to establish whether this was a simple faint and the child is otherwise healthy, or whether this the syncope was due to a significant underlying health problem. Simple faints without underlying pathology are harmless and have no long term implications.

Primary syncope (simple fainting):

Dehydration
Missed meals
Extended standing in a warm environment, such as a school assembly
A vasovagal response to a stimuli, such as sudden surprise, pain or the sight of blood
Secondary causes:

Hypoglycaemia
Dehydration
Anaemia
Infection
Anaphylaxis
Arrhythmias
Valvular heart disease
Hypertrophic obstructive cardiomyopathy

Question 4

History of syncope

Answer 4

Take a thorough history focusing on eliciting several key points, ideally with the help of a witness:

Features that distinguish a syncopal episode from a seizure
After exercise? Syncope after exercise is more likely to be secondary to an underlying condition.
Triggers?
Concurrent illness? Do they have a fever or signs of infection?
Injury secondary to the faint? Do they have a head injury?
Associated cardiac symptoms, such as palpitations or chest pain?
Associated neurological symptoms?
Seizure activity?
Family history, particularly cardiac problems or sudden death?

Syncope
Prolonged upright position before the event
Lightheaded before the event
Sweating before the event
Blurring or clouding of vision before the event
Reduced tone during the episode
Return of consciousness shortly after falling
No prolonged post-ictal period

Seizure
Epilepsy aura (smells, tastes or deja vu) before the event
Head turning or abnormal limb positions
Tonic clonic activity
Tongue biting
Cyanosis
Lasts more than 5 minutes
Prolonged post-ictal period

Question 5

Examination after syncope

Answer 5

Perform a thorough examination focusing on eliciting several key points:

Are there any physical injuries as a result of the faint, for example a head injury?
Is there a concurrent illness, for example an infection or gastroenteritis?
Neurological examination
Cardiac examination, specifically assessing pulses, heart rate, rhythm and murmurs
Lying and standing blood pressure

Question 6

Investigating syncope

Answer 6

ECG, particularly assessing for arrhythmia and the QT interval for long QT syndrome
24 hour ECG if paroxysmal arrhythmias are suspected
Echocardiogram if structural heart disease is suspected
Bloods, including a full blood count (anaemia), electrolytes (arrhythmias and seizures) and blood glucose (diabetes)

Question 7

Managing syncope

Answer 7

Fainting is common in children, particularly in teenage girls. They usually resolve by the time they reach adulthood. The most important aspect of management is making a confident diagnosis and excluding other pathology.

Seizures or underlying pathology need to be managed by an appropriate specialist.

Once a simple vasovagal episode is diagnosed, reassurance and simple advice can be given to:

Avoid dehydration
Avoid missing meals
Avoid standing still for long periods
When experiencing prodromal symptoms such as sweating and dizziness, sit or lie down, have some water or something to eat and wait until feeling better

Question 8

Generalised Tonic-Clonic Seizures

Answer 8

These are what most people think of with an epileptic seizure. There is loss of consciousness and tonic (muscle tensing) and clonic (muscle jerking) movements. Typically the tonic phase comes before the clonic phase. There may be associated tongue biting, incontinence, groaning and irregular breathing.

After the seizure there is a prolonged post-ictal period where the person is confused, drowsy and feels irritable or low.

Management of tonic-clonic seizures is with:

First line: sodium valproate
Second line: lamotrigine or carbamazepine

Question 9

Focal seizures

Answer 9

Focal seizures start in the temporal lobes. They affect hearing, speech, memory and emotions. There are various ways that focal seizures can present:

Hallucinations
Memory flashbacks
Déjà vu
Doing strange things on autopilot

One way to remember the treatment is that the choice of medication is the reverse of tonic-clonic seizures:

First line: carbamazepine or lamotrigine
Second line: sodium valproate or levetiracetam

Question 10

Absence seizures

Answer 10

Absence seizures typically happen in children. The patient becomes blank, stares into space and then abruptly returns to normal. During the episode they are unaware of their surroundings and won’t respond. These typically only lasts 10 to 20 seconds. Most patients (more than 90%) stop having absence seizures as they get older. Management is:

First line: sodium valproate or ethosuximide

Question 11

Atonic seizures

Answer 11

Atonic seizures are also known as drop attacks. They are characterised by brief lapses in muscle tone. These don’t usually last more than 3 minutes. They typically begin in childhood. They may be indicative of Lennox-Gastaut syndrome. Management is:

First line: sodium valproate
Second line: lamotrigine

Question 12

Myoclonic seizures

Answer 12

Myoclonic seizures present as sudden brief muscle contractions, like a sudden “jump”. The patient usually remains awake during the episode. They occur in various forms of epilepsy but typically happen in children as part of juvenile myoclonic epilepsy. Management is:

First line: sodium valproate
Other options: lamotrigine, levetiracetam or topiramate

Question 13

Infantile spasms

Answer 13

This is also known as West syndrome. It is a rare (1 in 4000) disorder starting in infancy at around 6 months of age. It is characterised by clusters of full body spasms. There is a poor prognosis: 1/3 die by age 25, however 1/3 are seizure free. It can be difficult to treat but first line treatments are:

Prednisolone
Vigabatrin

Question 14

Investigation and diagnosis of seizures

Answer 14

A good history is the key to a diagnosis of epilepsy. It is important to establish that any episodes were seizures, as opposed to vasovagal episodes or febrile convulsions. Try to identify the type of seizure. Patients with a clear history of a febrile convulsion or vasovagal episode do not require further investigations.

An electroencephalogram (EEG) can show typical patterns in different forms of epilepsy and support the diagnosis. Perform an EEG after the second simple tonic-clonic seizure. Children are allowed one simple seizure before being investigated for epilepsy.

An MRI brain can be used to visualise the structure of the brain. It is used to diagnose structural problems that may be associated with seizures and other pathology such as tumours. It should be considered when:

The first seizure is in children under 2 years
Focal seizures
There is no response to first line anti-epileptic medications

Additional investigations can be considered to exclude other pathology that may cause seizures:

ECG to exclude problems in the heart.
Blood electrolytes including sodium, potassium, calcium and magnesium
Blood glucose for hypoglycaemia and diabetes
Blood cultures, urine cultures and lumbar puncture where sepsis, encephalitis or meningitis is suspected

Question 15

General advice for seizures

Answer 15

Patients and families presenting with seizures need to be given advice about safety precautions, recognising, managing and reporting further seizures. It is important to avoid situations where a seizure may put the child in danger, with advise to:

Take showers rather than baths
Be very cautious with swimming unless seizures are well controlled and they are closely supervised
Be cautious with heights
Be cautious with traffic
Be cautious with any heavy, hot or electrical equipment

Older teenagers with epilepsy will need to avoid driving unless they meet specific criteria regarding control of their epilepsy. These rules change frequently so it is always worth looking them up if advising patients.

Question 16

Anti-epileptic medications

Answer 16

There are a number of maintenance anti-epileptic drugs that work by raising the seizure threshold and reducing the likelihood of the patient having a seizure. These will be initiated, monitored and titrated by a paediatric specialist with expertise in epilepsy.

Sodium Valproate

This is a first line option for most forms of epilepsy (except focal seizures). It works by increasing the activity of GABA, which has a relaxing effect on the brain. Notable side effects of sodium valproate include:

Teratogenic, so patients need careful advice about contraception
Liver damage and hepatitis
Hair loss
Tremor

There are a lot of warning about the teratogenic effects of sodium valproate and NICE updated their guidelines in 2018 to reflect this. It must be avoided in girls unless there are no suitable alternatives and strict criteria are met to ensure they do not get pregnant.

Carbamazepine

This is first line for focal seizures. Notable side effects are:

Agranulocytosis
Aplastic anaemia
Induces the P450 system so there are many drug interactions

Phenytoin

Notable side effects:

Folate and vitamin D deficiency
Megaloblastic anaemia (folate deficiency)
Osteomalacia (vitamin D deficiency)

Ethosuximide

Notable side effects:

Night terrors
Rashes

Lamotrigine

Notable side effects:

Stevens-Johnson syndrome or DRESS syndrome. These are life threatening skin rashes.
Leukopenia

Question 17

Managing seizures

Answer 17

Put the patient in a safe position (e.g. on a carpeted floor)
Place in the recovery position if possible
Put something soft under their head to protect against head injury
Remove obstacles that could lead to injury
Make a note of the time at the start and end of the seizure
Call an ambulance if lasting more than 5 minutes or this is their first seizure.

Question 18

Status Epilepticus

Answer 18

Status epilepticus is an important condition you need to be aware of and how to treat. It is a medical emergency.

It is defined as a seizure lasting more than 5 minutes or 2 or more seizures without regaining consciousness in the interim.

Management of status epileptics in the hospital (take an ABCDE approach):

Secure the airway
Give high-concentration oxygen
Assess cardiac and respiratory function
Check blood glucose levels
Gain intravenous access (insert a cannula)
IV lorazepam, repeated after 10 minutes if the seizure continues
If the seizures persist the final step is an infusion of IV phenobarbital or phenytoin. At this point intubation and ventilation to secure the airway needs to be considered, along with transfer to the intensive care unit if appropriate.

Medical options in the community:

Buccal midazolam
Rectal diazepam

Question 19

Febrile convulsions

Answer 19

Febrile convulsions are a type of seizure that occurs in children with a high fever. They are not caused by epilepsy or other underlying neurological pathology, such as meningitis or tumours. By definition, febrile convulsions occur only in children between the ages of 6 months and 5 years.

Question 20

Simple febrile convulsions

Answer 20

Simple febrile convulsions are generalised, tonic clonic seizures. They last less than 15 minutes and only occur once during a single febrile illness.

Question 21

Complex febrile convulsions

Answer 21

Febrile convulsions can be described as complex when they consist of partial or focal seizures, last more than 15 minutes or occur multiple times during the same febrile illness.

Question 22

Diagnosing febrile convulsions

Answer 22

In order to make a diagnosis of a febrile convulsion, other neurological pathology must be excluded. The differential diagnoses of a febrile convulsion are:

Epilepsy
Meningitis, encephalitis or another neurological infection such as cerebral malaria
Intracranial space occupying lesions, for example brain tumours or intracranial haemorrhage
Syncopal episode
Electrolyte abnormalities
Trauma (always think about non accidental injury)
A typical presentation is a child around 18 months of age presenting with a 2 – 5 minute tonic clonic seizure during a high fever. The fever is usually caused by an underlying viral illness or bacterial infection such as tonsillitis. Once a diagnosis of a febrile convulsion has been made, look for the underlying source of infection.

Question 23

Managing febrile convulsions

Answer 23

In the febrile child the first stage is to identify and manage the underlying source of infection and control the fever with simple analgesia such as paracetamol and ibuprofen. Simple febrile convulsions do not require further investigations and parents can be reassured and educated about the condition. Complex febrile convulsions may need further investigation.

Give parents advice on managing a seizure if a further episode occurs:

Stay with the child
Put the child in a safe place, for example on a carpeted floor with a pillow under their head
Place them in the recovery position and away from potential sources of injury
Don’t put anything in their mouth
Call an ambulance if the seizure lasts more than 5 minutes
The first seizure should always result in a trip to hospital for assessment, however if parents are confident in subsequent events and can safely manage the child at home then they can visit their GP at the next available opportunity.

Question 24

Prognosis of febrile convulsions

Answer 24

Febrile convulsions do not typically cause any lasting damage. One in three will have another febrile convulsion. The risk of developing epilepsy is:

1.8% for the general population
2-7.5% after a simple febrile convulsion
10-20% after a complex febrile convulsion

Question 25

Breath holding spells

Answer 25

Breath holding spells are also known as breath holding attacks. They are involuntary episodes during which a child holds their breath, usually triggered by something upsetting or scaring them. They typically occur between 6 and 18 months of age. The child has no control over the breath holding spells. They are not harmful in the long term, do not lead to epilepsy and most children outgrow them by 4 or 5 years.

They are often divided into two types: cyanotic breath holding spells and pallid breath holding spells (also known as reflex anoxic seizures).

Cyanotic Breath Holding Spells

Cyanotic breath holding spells occur when the child is really upset, worked up and crying. After letting out a long cry they stop breathing, become cyanotic and lose consciousness. Within a minute they regain consciousness and start breathing. They can be a bit tired and lethargic after an episode.

Reflex Anoxic Seizures

Reflex anoxic seizures occur when the child is startled. The vagus nerve sends strong signals to the heart that causes it to stop beating. The child will suddenly go pale, lose consciousness and may start to have some seizure-like muscle twitching. Within 30 seconds the heart restarts and the child becomes conscious again.

Question 26

Managing breath holding spells

Answer 26

After excluding other pathology and making a diagnosis, educating and reassuring parents about breath holding spells is the key to management.

Breath holding spells have been linked with iron deficiency anaemia. Treating the child if they are iron deficiency anaemic can help minimise further episodes.

Question 27

Causes of Headaches in Children

Answer 27

Tension headaches
Migraines
Ear, nose and throat infection
Analgesic headache
Problems with vision
Raised intracranial pressure
Brain tumours
Meningitis
Encephalitis
Carbon monoxide poisoning

Question 28

Tension Headaches

Answer 28

Tension headaches are very common. Classically they produce a mild ache across the forehead and pain or pressure in a band-like pattern around the head. Tension headaches comes on and resolve gradually and don’t produce visual changes or pulsating sensations. They are typically symmetrical.

Symptoms may be very non-specific in younger children. They may become quiet, stop playing, turn pale or become tired. They tend to resolve more quickly in children compared with adults, often within 30 minutes.

There are certain triggers for tension headaches in children:

Stress, fear or discomfort
Skipping meals
Dehydration
Infection

Management is with reassurance, analgesia, regular meals, avoiding dehydration and reducing stress.

Question 29

Migraines

Answer 29

Migraines are a complex neurological condition that cause headache and other associated symptoms. They occur in “attacks” that often follow a typical pattern.

There are several types of migraine:

Migraine without aura
Migraine with aura
Silent migraine (migraine with aura but without a headache)
Hemiplegic migraine
Abdominal migraine
The pathophysiology of migraine has been studied for decades. Various mechanisms and theories have developed. There is no simple explanation for why migraines occur and it may be a combination of structural, functional, chemical, vascular and inflammatory factors.

Migraines present differently to tension headaches. Symptoms tend to be:

Unilateral
More severe
Throbbing in nature
Take longer to resolve
Migraines are often associated with:

Visual aura
Photophobia and phonophobia
Nausea and vomiting
Abdominal pain
Management of migraines in children:

Rest, fluids and low stimulus environment
Paracetamol
Ibuprofen
Sumatriptan
Antiemetics, such as domperidone (unless contraindicated)
Where the migraines are having a significant impact on life, for example frequent attacks or missing school, prophylactic treatment can be tried to reduce the frequency and severity of the migraines. This is usually guided by a specialist. Options for migraine prophylaxis are:

Propranolol (avoid in asthma)
Pizotifen (often causes drowsiness)
Topiramate (girls with child bearing potential need highly effective contraception as it is very teratogenic).
Children are more likely than adults to suffer with a condition called abdominal migraine. This may occur in young children before they develop traditional migraines as they get older. They present with episodes of central abdominal pain lasting more than 1 hour. Examination will be normal. There may be associated:

Nausea and vomiting
Anorexia
Headache
Pallor
TOM TIP: When a patient presents with possible migraines ask about recurrent central abdominal pain as a child. They may have a history of abdominal migraine that started before the headaches.

Question 30

Infection causes of headaches

Answer 30

Infections can cause headaches in children. In a child with a new headache, always check for symptoms and signs of a viral upper respiratory tract infection, otitis media, sinusitis and tonsillitis. The headache should resolve along with the infection. Paracetamol and ibuprofen can be helpful for symptomatic relief.

Sinusitis causes a headache associated with inflammation in the ethmoidal, maxillary, frontal or sphenoidal sinuses. This usually produces facial pain behind the nose, forehead and eyes. There is often tenderness over the effected sinuses, which helps to establish the diagnosis. Sinusitis usually resolves within 2 – 3 weeks. Most sinusitis is viral.

Question 31

Cerebral palsy

Answer 31

Cerebral palsy (CP) is the name given to the permanent neurological problems resulting from damage to the brain around the time of birth. It is not a progressive condition, however the nature of the symptoms and problems may change over time during growth and development. There is huge variation in the severity and type of symptoms, ranging from completely wheelchair bound and dependent on others for all activities of daily living, to para-olympic athletes with only subtle problems with coordination or mobility.

Question 32

Causes of Cerebral Palsy

Answer 32

Antenatal:

Maternal infections
Trauma during pregnancy
Perinatal:

Birth asphyxia
Pre-term birth
Postnatal:

Meningitis
Severe neonatal jaundice
Head injury

Question 33

Type of Cerebral Palsy

Answer 33

Spastic: hypertonia (increased tone) and reduced function resulting from damage to upper motor neurones
Dyskinetic: problems controlling muscle tone, with hypertonia and hypotonia, causing athetoid movements and oro-motor problems. This is the result of damage to the basal ganglia.
Ataxic: problems with coordinated movement resulting from damage to the cerebellum
Mixed: a mix of spastic, dyskinetic and/or ataxic features
Spastic CP is also known as pyramidal CP. Dyskinetic CP is also known as athetoid CP and extrapyramidal CP.

Question 34

Patterns of Spastic Cerebral Palsy

Answer 34

Monoplegia: one limb affected
Hemiplegia: one side of the body affected
Diplegia: four limbs are affects, but mostly the legs
Quadriplegia: four limbs are affected more severely, often with seizures, speech disturbance and other impairments

Question 35

Presentation of cerebral palsy

Answer 35

It is difficult to predict the extent of cerebral palsy or even whether it will occur based on the events in the peri-natal period. Children at risk of developing cerebral palsy, such as those with hypoxic-ischaemic encephalopathy, need to be followed up to identify any signs and symptoms that develop.

Signs and symptoms of cerebral palsy will become more evident during development:

Failure to meet milestones
Increased or decreased tone, generally or in specific limbs
Hand preference below 18 months is a key sign to remember for exams
Problems with coordination, speech or walking
Feeding or swallowing problems
Learning difficulties

Question 36

Neurological examination of cerebral palsy

Answer 36

You can gain a lot of information about a child from their gait:

Hemiplegic / diplegic gait: indicates an upper motor neurone lesion
Broad based gait / ataxic gait: indicates a cerebellar lesion
High stepping gait: indicates foot drop or a lower motor neurone lesion
Waddling gait: indicates pelvic muscle weakness due to myopathy
Antalgic gait (limp): indicates localised pain

Finding
Upper Motor Neurone
Lower Motor Neurone

Inspection
Muscle bulk preserved
Reduced muscle bulk with fasciculations

Tone
Hypertonia
Hypotonia

Power
Slightly reduced
Dramatically reduced

Reflexes
Brisk
Reduced

Patients with cerebral palsy may have a hemiplegic or diplegic gait. This gait is caused by increased muscle tone and spasticity in the legs. The leg will be extended with plantar flexion of the feet and toes. This means they have to swing the leg around in a large semicircle when moving their leg from behind them to in front. There is not enough space to swing the extended leg in a straight line below them.

They will have signs of an upper motor neurone lesion, with good muscle bulk, increased tone, brisk reflexes and slightly reduced power. Power may be normal. Look for athetoid movements that indicate extrapyramidal (basal ganglia) involvement. Test for coordination to look for cerebellar involvement.

TOM TIP: Get used to assessing and recognising the patterns of upper and lower motor neurone lesions. Cerebral palsy is a perfect condition for examiners to bring to OSCEs, because signs are reliable and patients are stable. The differential diagnosis of an upper motor neurone lesion is acquired brain injury or a tumour.

Question 37

Complications and conditions associated with cerebral palsy

Answer 37

Learning disability
Epilepsy
Kyphoscoliosis
Muscle contractures
Hearing and visual impairment
Gastro-oesophageal reflux

Question 38

Managing cerebral palsy

Answer 38

Cerebral palsy is a permanent condition with problems that are life-long. It cannot be cured, but there are many ways to manage the symptoms and maximise function. The focus is on supporting the patient to achieve the most fulfilled and independent life. When asked how you would manage complex conditions such as cerebral palsy the answer should always start with “management will involve a multi-disciplinary team approach”.

Physiotherapy is used to stretch and strengthen muscles, maximise function and prevent muscle contractures.

Occupational therapy is used to help patients manage their everyday activities, such as getting dressed and using the bathroom. That can involve techniques to perform tasks despite disability. They can also make adaptations and supply equipment, such as rails for assistance or fitting a hoist for a patient who is entirely wheelchair bound.

Speech and language therapy can help with speech and swallowing. When swallowing difficultly prevents them meeting their nutritional requirements they may require an NG tube or PEG tube to be fitted.

Dieticians can help ensure they meet nutritional requirements. Some children may require PEG feeding through a port on their abdomen that gives direct access to the stomach.

Orthopaedic surgeons can perform procedures to release contractures or lengthen tendons (tenotomy).

Paediatricians will regularly see the child to optimise their medications. This may involve:

Muscle relaxants (e.g. baclofen) for muscle spasticity and contractures
Anti-epileptic drugs for seizures
Glycopyrronium bromide for excessive drooling
Social workers to help with benefits and support.

Charities and support groups provide opportunities to connect with others affected by cerebral palsy and learn and share information on the condition.

Question 39

Squint

Answer 39

Squint refers to misalignment of the eyes. It is is also known as strabismus. When the eyes are not aligned, the images on the retina do not match and the person will experience double vision.

When this occurs in childhood, before the eyes have fully established their connections with the brain, the brain will cope with this misalignment by reducing the signal from the less dominant eye. This results in one eye they use to see (the dominant eye) and one eye they ignore (the “lazy eye”). If this is not treated, this “lazy eye” becomes progressively more disconnected from the brain and over time the problem becomes worse. This is called amblyopia.

Concomitant squints are due to differences in the control of the extra ocular muscles. The severity of the squint can vary.

Paralytic squints are rare. They are due to paralysis in one or more of the extra ocular muscles.

Question 40

Definitions of squints

Answer 40

Strabismus: the eyes are misaligned
Amblyopia: the affected eye becomes passive and has reduced function compared to the other dominant eye
Esotropia: inward positioned squint (affected eye towards the nose)
Exotropia: outward positioned squint (affected eye towards the ear)
Hypertropia: upward moving affected eye
Hypotropia: downward moving affected eye

Question 41

Causes of squint

Answer 41

Causes of squint in otherwise healthy children are usually idiopathic, meaning there is not a specific underlying cause. Other causes of squint include:

Hydrocephalus
Cerebral palsy
Space occupying lesions, for example retinoblastoma
Trauma

Question 42

Examining strabismus

Answer 42

General inspection
Eye movements
Fundoscopy (or red reflex) to rule out retinoblastoma, cataracts and other retinal pathology
Visual acuity
Hirschberg’s test: shine a pen-torch at the patient from 1 meter away. When they look at it, observe the reflection of the light source on their cornea. The reflection should be central and symmetrical. Deviation from the centre will indicate a squint. Make a note of the affected eye and the direction the eye deviates.

Cover test: cover one eye and ask the patient to focus on an object in front of them. Move the cover across to the opposite eye and watch the movement of the previously covered eye. If this eye moves inwards, it had drifted outwards when covered (exotropia) and if it moves outwards it means it had drifted inwards when covered (esotropia).

Question 43

Managing strabismus

Answer 43

Up until the age of 8 years the visual fields are still developing, therefore treatment needs to start before 8 years. The earlier the better. Delayed treatment increases the risk of the squint becoming permanent.

An occlusive patch can be used to cover the good eye and force the weaker eye to develop. An alternative to the patch may involve using atropine drops in the good eye, causing vision in that eye to be blurred.

Management is coordinated by an ophthalmologist. It will be important to treat any underlying pathology, such as cataracts. Refractive errors can be corrected with corrective lenses.

Question 44

Hydrocephalus

Answer 44

Hydrocephalus describes cerebrospinal fluid (CSF) building up abnormally within the brain and spinal cord. This is a result of either over-production of CSF or a problem with draining or absorbing CSF.

Question 45

Normal CSF Physiology

Answer 45

There are four ventricles in the brain: two lateral ventricles, the third and the fourth ventricles. The ventricles contain CSF. The CSF provides a cushion for the brain tissue. CSF is created in the four choroid plexuses (one in each ventricle) and by the walls of the ventricles. CSF is absorbed into the venous system by the arachnoid granulations.

Question 46

Congenital causes of hydrocephalus

Answer 46

The most common cause of hydrocephalus is aqueductal stenosis, leading to insufficiency drainage of CSF. The cerebral aqueduct that connects the third and fourth ventricle is stenosed (narrowed). This blocks the normal flow of CSF out of the third ventricle, causing CSF to build up in the lateral and third ventricles.

Other causes:

Arachnoid cysts can block the outflow of CSF if they are large enough
Arnold-Chiari malformation is where the cerebellum herniates downwards through the foramen magnum, blocking the outflow of CSF
Chromosomal abnormalities and congenital malformations can cause obstruction to CSF drainage.

Question 47

Presentation of hydrocephalus

Answer 47

The cranial bones in babies are not fused at the sutures until around 2 years of age. Therefore, the skull is able to expand to fit the cranial contents. When a baby has hydrocephalus it causes outward pressure on the cranial bones. Therefore, babies with hydrocephalus will have an enlarged and rapidly increasing head circumference (occipito-frontal circumference).

Other signs:

Bulging anterior fontanelle
Poor feeding and vomiting
Poor tone
Sleepiness

Question 48

Ventriculoperitoneal shunt

Answer 48

Placing a VP shunt that drains CSF from the ventricles into another body cavity is the mainstay of treatment for hydrocephalus. Usually the peritoneal cavity is used to drain CSF, as there is plenty of space and it is easily reabsorbed. The surgeon places a small tube (catheter) through a small hole in the skull at the back of the head and into one of the ventricles. A valve on the end of this tube is placed subcutaneously, and a catheter on the other side of the valve runs under the skin into the peritoneal cavity. The valve helps to regulate the amount of CSF that drains from the ventricles.

VP Shunt Complications

Infection
Blockage
Excessive drainage
Intraventricular haemorrhage during shunt related surgery
Outgrowing them (they typically need replacing around every 2 years as the child grows)

Question 49

Craniosynostosis

Answer 49

Craniosynostosis occurs when the skull sutures close prematurely. This results in abnormal head shapes and restriction to the growth of the brain.

If left untreated it will lead to raised intracranial pressure, with resulting symptoms of developmental delay, cognitive impairment, vomiting, irritability, visual impairment, neurological symptoms and seizures.

Presentation

The main presenting features is an abnormal head shape depending, on the affected cranial suture:

Type of Synostosis
Affected Suture
Head Shape

Saggital Synostosis
Saggital suture
Long and narrow from front to back

Coronal Synostosis
Coronal suture
Bulging on one side of the forehead

Metopic Synostosis
Metopic suture
Pointy triangular forehead

Lambdoid Synostosis
Lambdoid suture
Flattening on one side of the occiput

Other presenting features:

Anterior fontanelle closure before 1 year of age
Small head in proportion to the body

Investigations

Where there are suspicions about craniosynostosis the patient should be referred to a specialist for further investigations. The first line investigation is a skull xray.

CT head with bone views is used to confirm the diagnosis or exclude it if there is doubt on the xray.

Management

Mild cases may be monitored and followed up over time. More severe cases require surgery for surgical reconstruction of the skull.

The prognosis is usually good with proper management. They will have a lifelong scar on the scalp where the surgery was performed.

Question 50

Plagiocephaly and brachycephaly

Answer 50

Plagiocephaly and brachycephaly are very common conditions that cause abnormal head shapes in otherwise normal health babies. Plagio- translates as oblique, or slanted. Plagiocephaly refers to flattening of one area of the baby’s head. Brachy- translates as short. Brachycephaly refers to flattening at the back of the head, resulting in a short head from back to front.

These conditions occur where a baby had a tendency to rest their head on a particular point, resulting in the skull bones and sutures moulding with gravity to create an abnormal head shape. This is called positional plagiocephaly. This has become more common as parents are advised to rest babies on their back to reduce the risk of sudden infant death syndrome.

Presentation

The typical presentation is a baby aged 3 – 6 months with an abnormal head shape. They often have a history of preferring to sleep on one side of their head.

Question 51

Managing plagiocephaly and brachycephaly

Answer 51

Exclude craniosynotosis with a thorough history and properly palpating the sutures. Where there is doubt refer for specialist assessment and imaging.

Look for congenital muscular torticollis (CMT), which is a shortening of the sternocleidomastoid muscle on one side. This may be the reason the child always rests on one side of their head. Physiotherapy can help with movement exercises to treat the torticollis.

Reassurance is key. An abnormal head shape can cause a lot of parental anxiety. In the vast majority of cases the head shape will return to normal as the child grows.

Simple measures can be taken to encourage the baby to avoid resting on the flattened area:

Positioning them on the rounded side for sleep
Supervised tummy time
Using rolled towels or other props
Minimising time in pushchairs and car seats
Plagiocephaly helmets are marketed as a treatment option for plagiocephaly. They have some limitations in that they need to be used for the vast majority of the day and can lead to skin problems (e.g. contact dermatitis) and psychosocial problems. They are not routinely available on the NHS.

Question 52

Muscular Dystrophy

Answer 52

Muscular dystrophy is an umbrella term for genetic conditions that cause gradual weakening and wasting of muscles.

Question 53

Types of Muscular Dystrophy

Answer 53

Duchennes muscular dystrophy
Beckers muscular dystrophy
Myotonic dystrophy
Facioscapulohumeral muscular dystrophy
Oculopharyngeal muscular dystrophy
Limb-girdle muscular dystrophy
Emery-Dreifuss muscular dystrophy

Question 54

Gower’s sign

Answer 54

Children with proximal muscle weakness use a specific technique to stand up from a lying position. This is called Gower’s sign.

To stand up, they get onto their hands and knees, then push their hips up and backwards like the “downward dog” yoga pose. They then shift their weight backwards and transfer their hands to their knees. Whilst keeping their legs mostly straight they walk their hands up their legs to get their upper body erect. This is because the muscles around the pelvis are not strong enough to get their upper body erect without the help of their arms.

TOM TIP: Gower’s sign is a favourite in exams. If there is a 5 year old boy presenting with vague symptoms of muscle weakness and the description is that you notice them using their hands on their legs to help them stand up, the answer is probably Duchennes muscular dystrophy. They may ask “what is the underlying genetic inheritance of the most likely cause?” The answer is X-linked recessive.

Question 55

Managing Muscular Dystrophy

Answer 55

There is no curative treatment for muscular dystrophy. Management is aimed at allowing the person to have the highest quality of life for the longest time possible. This usually involves input from occupational therapy, physiotherapy and medical appliances (such as wheelchairs and braces) as well as surgical and medical management of complications such as spinal scoliosis and heart failure.

Question 56

Duchennes Muscular Dystrophy

Answer 56

Duchennes muscular dystrophy is the most likely muscular dystrophy to turn up in your exams. It is caused by a defective gene for dystrophin on the X-chromosome. Dystrophin is a protein that helps hold muscles together at the cellular level. Given that boys have a single X-chromosome and girls have two, girls have a spare copy of the dystrophin gene. Female carriers of the condition do not usually notice any symptoms. This makes Duchennes muscular dystrophy an X-linked recessive condition. If a mother is a carrier (meaning she has one faulty gene) and she has a child, that child will have a 50% change of being a carrier if they female and 50% change of having the condition if they are male.

Boys with Duchennes present around 3 – 5 years with weakness in the muscles around their pelvis. The weakness tends to be progressive and eventually all muscles will be affected. They are usually wheelchair bound by the time they become a teenager. They have a life expectance of around 25 – 35 years with good management of the cardiac and respiratory complications.

Oral steroids have been shown to slow the progression of muscle weakness by as much as two years. Creatine supplementation can give a slight improvement in muscle strength. Genetic trials are ongoing.

Question 57

Beckers Muscular Dystrophy

Answer 57

Beckers muscular dystrophy is very similar to Duchennes, however the dystrophin gene is less severely affected and maintains some of its function. The clinical course is less predictable than Duchennes. Symptoms only start to appear around 8 – 12 years. Some patient require wheelchairs in their late 20s or 30s . Others able to walk with assistance into later adulthood. Management is similar to Duchennes.

Question 58

Myotonic Dystrophy

Answer 58

Myotonic dystrophy is a genetic disorder that usually presents in adulthood. Typical features are:

Progressive muscle weakness
Prolonged muscle contractions
Cataracts
Cardiac arrhythmias
TOM TIP: The key feature of myotonic dystrophy to remember is the prolonged muscle contraction. This may present in exams with a patient that is unable to let go after shaking someones hand, or unable to release their grip on a doorknob after opening a door. When doing an upper limb neurological examination always shake the patients hand and observe for difficulty releasing their grip.

Question 59

Facioscapulohumeral Muscular Dystrophy

Answer 59

Facioscapulohumeral muscular dystrophy usually presents in childhood with weakness around the face, progressing to the shoulders and arms. A classic initial symptom is sleeping with their eyes slightly open and weakness in pursing their lips. They are unable to blow their cheeks out without air leaking from their mouth.

Question 60

Oculopharyngeal Muscular Dystrophy

Answer 60

Oculopharyngeal muscular dystrophy usually presents in late adulthood with weakness of the ocular muscles (around the eyes) and pharynx (around the throat) as the name suggests. It typically presents with bilateral ptosis, restricted eye movement and swallowing problems. Muscles around the limb girdles are also affected to varying degrees.

Question 61

Limb-girdle Muscular Dystrophy

Answer 61

Limb-girdle muscular dystrophy usually presents in teenage years with progressive weakness around the limb girdles (hips and shoulders).

Question 62

Emery-Dreifuss Muscular Dystrophy

Answer 62

Emery-Dreifuss muscular dystrophy usually presents in childhood with contractures, most commonly in the elbows and ankles. Contractures are shortening of muscles and tendons that restrict the range of movement in limbs. Patients also suffer with progressive weakness and wasting of muscles, starting with the upper arms and lower legs.

Question 63

Spinal muscular atrophy

Answer 63

Spinal muscular atrophy (SMA) is a rare autosomal recessive condition that causes a progressive loss of motor neurones, leading to progressive muscular weakness.

Spinal muscular atrophy affects the lower motor neurones in the spinal cord. This means there will be lower motor neurone signs, such as fasciculations, reduced muscle bulk, reduced tone, reduced power and reduced or absent reflexes.

Question 64

Categories of spinal muscular atrophy

Answer 64

There are four categories of spinal muscular atrophy that are numbered from most to least severe. SMA type 2 is the most common type.

SMA type 1 has an onset in the first few months of life, usually progressing to death within 2 years.

SMA type 2 has an onset within the first 18 months. Most never walk, but survive into adulthood.

SMA type 3 has an onset after the first year of life. Most walk without support, but subsequently loose that ability. Respiratory muscles are less affected and life expectancy is close to normal.

SMA type 4 has an onset in the 20s. Most will retain the ability to walk short distances but require a wheelchair for mobility. Everyday tasks can lead to significant fatigue. Respiratory muscles and life expectancy are not affected.

Question 65

Managing spinal muscular atrophy

Answer 65

There is no cure for spinal muscular atrophy. Management is supportive and involves the multi-disciplinary team.

Physiotherapy can be helpful in maximising strength in the muscles and retaining respiratory function. Splints, braces and wheelchairs can be used to maximise function.

Respiratory support with non-invasive ventilation may be required to prevent hypoventilation and respiratory failure, particularly during sleep. Children with SMA type 1 may require a tracheostomy with mechanical ventilation, which can dramatically extend life by supporting failing respiratory muscles.

Percutaneous endoscopic gastrostomy (PEG) feeding may be required when a weak swallow makes swallowing unsafe.