Neurology Flashcards
Sodium valproate: indications and side effects?
Use: (Think ‘generalised’)
- Generalised tonic clonic
- Absence
- Atypical absence
- Myoclonic
Side effect:
- Teratogen (neural tube)
- Hyperammonaemia
- Thrombocytopenia (dose-related)
- Weight gain
Carbamazepine: indications and side effects?
Use:
1. Focal seizures +/-secondary generalised
Side effect:
- Leukopenia
- Hepatotoxicity
- SIADH -> hyponatraemia
Phenytoin: indications and side effects?
Use:
- Status epilepticus
- Focal seizures +/- secondary generalised
Side effects:
- P450 induction
- Hirsutism
- Gum enlargement
- Teratogen (hydantoin syndrome)
- Ataxia, rash
- Steven Johnson syndrome
Ethosuximide: indications and side effect?
Use:
1. Absence seizures
Side effect:
- (F)atigue
- (G)I upset
- (H)eadache
- (I)tching
- Steven (J)ohnson
Phenobarbitol: indications and side effect?
Use: (only in infants i.e. ‘phenoBABYtol’)
- Generalised tonic-clonic
- Focal seizure
Side effect:
- Severe behavioural changes
- Impaired cognition
Lamotrigine: indications and side effect?
Use:
- Lennox-Gastaut
- Focal seizures
Side effect:
- Steven Johnson syndrome
- Haemophagocytic lymphohistiocytosis
Levetiracetam: indications and side effect?
Use:
- Focal seizures (with impaired consciousness >4 years)
- Generalised tonic-clonic (>6 years)
- Juvenile myoclonic epilepsy (>12 years)
Side effect:
1. Behavioural (irritability, aggression)
Topiramate: indications and side effect?
Use:
- Focal seizure
- Generalised seizure
Side effect:
- Kidney (s)tone
- (S)low cognition
- (S)kinny (weight loss)
- (S)ight threatened (glaucoma)
- (S)peech difficulties (word finding)
Oxcarbazepine: indications and treatment?
Use:
1. Benign Rolandic epilepsy of childhood (centrotemporal spikes)
Side effect:
- Ataxia
- Nystagmus
- Hyponatraemia
Which areas of the brain correspond to motor, adversive, somatosensory or emotional changes?
Focal motor = precentral gyrus
Focal adversive (forceful turning to one side) = mesial frontal lobe
Focal somatosensory = parietal
Emotional/hallucinatory = temporal
What is the treatment of choice for focal seizures?
Carbamazepine
Oxcarbazepine
Phenytoin
What is the treatment of infantile spasms?
ACTH
Vigabatrin
ACTH side effect = HTN, irritability, ionfection
Vigabatrin side effect = Vision (permanent blindness)
-> best to use with coexistant tuberous sclerosis
What is West syndrome?
Triad of: 1. Infantile spasm 2. Intellectual disability 3. Hypsarrhythmia = high voltage, irregular, slow waves
What is the EEG with Lennox Gastaut syndrome?
Generalised, bilaterally synchronous, sharp- and slow-wave complexes, occurring in repetitive fashion in long runs
a.k.a. ‘slow spike and wave’
What neurocutaneous syndrome is infantile spasms associated with?
Tuberous sclerosis
What neurocutaneous disease causes focal seizures contralateral to affected area?
Sturge-Weber
= IPSIlateral leptomeningeal angioma causing CONTRAlateral focal seizure
Triad:
- Port-wine stain
- Leptomeningeal angioma
- Glaucoma
Why is spinal muscular atrophy (SMA) a disease of motor, not sensory, deficit?
= ANTERIOR horn disease (degeneration)
Anterior horn = motor
Posterior horn = sensory
Lethal AR disorder (chromosome 5q)
Elevated CK is seen with what neuromuscular disease?
Duchenne and Becker
NOT elevated with SMA
Which is more severe - Duchenne or Becker?
Duchenne
= absent or deficient dystrophin protein
‘BECKER is BETTER’
= defective but not total absence of protein
What is the difference in myasthenia gravis vs. Lambert Eaton vs botulism?
MG = POST-synaptic (AChR destroyed)
LES = PRE-synaptic (voltage-gated calcium channel not releasing ACh; attacked by antibodies)
Botulism = PRE-synaptic (botulinum toxin inhibits ACh release)
What are the types of myasthenia gravis in children?
- Transient neonatal
- Congenital
- Juvenile
What is used to help diagnose myasthenia gravis?
ACh-receptor antibodies (AChR-Ab)
Muscle-specific receptor tyrosine kinase (MuSK) antibodies
EMG demonstrating electrodecrement
What is the most common myositis in children?
Juvenile dermatomyositis
What serum abnormality is seen in ataxia telangiectasia?
Elevated alpha fetoprotein
Decreased serum IgA
What is the difference between vestibular neuritis vs. labarynthitis?
Both due to viral/postviral inflammatory disorder of vestibular portion of CN VIII
Vestibular neuritis = auditory function preserved
Labarynthitis = unilateral hearing loss
What are the key physical findings in vestibular neuritis?
Nystagmus - horizontal or rotational
Positive head thrust (rapid turning of head toward lesion side -> patient unable to maintain visual fixation)
Gait instability = fall toward affected side
Where is the most common location for brain tumours in children?
Posterior
Describe the flow of CSF and their channels
CSF produced by choroid plexus in lateral, third and fourth ventricles
Lateral -> (foramen of Munro) -> third ventricle -> (aqueduct of Sylvius) -> fourth ventricle -> (foramina of Magendie (medial) and Luschka (lateral)) -> subarachnoid space
Absorbed by arachnoid granulatoions to dural venous sinus
What is a communicating hydrocephalus?
= impairment of CSF flow within the SUBARACHNOID SPACE or impairment of ABSORPTION (at villi)
A misnomer
Think of it as EXTERNAL hydrocephalus
How are the clinical symptoms of hydrocephalus related to anatomy?
Symptoms due to (1) ventricular distension; (2) increased ICP
Lateral ventricle dilation = ataxia + spasticity (lower»_space; upper as leg fibers closest to ventricles)
Third ventricle dilation = endocrine dysfunction (hypothalamic region) + visual dysfunction (proximity to anterior of third ventricle)
Cerebral aqueduct dilation = sun-setting eyes (compress periaqueductal vertical gaze center)
What type of sensory information does the dorsal column-medial lemniscus vs. anterolateral spinothalamic tract?
DCML
- Proprioception
- Fine touch
SPINOTHALAMIC
(Lateral)
1. Pain
2. Temperature
(Anterior)
- Crude touch
- Pressure
What vitamin deficiency causes treatment-resistant neonatal seizures?
Vitamin B6 (pyridoxine)
Required for synthesis of y-amniobutyric acid (GABA), which is the principle inhibitory neurotransmitter
What is elevated in the serum after a seizure?
Prolactin
But not routinely measured as per NICE
What is the most common aura pre-seizure?
Epigastric pain
Feeling of fear
What two antiepileptics are renally cleared?
Levetiracetam
Phenobarbitol (25%)
What is the most common posterior fossa tumour of childhood?
Cerebellar astrocytoma
What is Macewen’s sign
Percussion of skull -> cracked pot sound
Positive test = separation of sutures
-> seen in hydrocephalus, brain abscess
What is the familial cause of hydrocephalus due to?
Aqueductal stenosis
X-linked
Note: NF-1 can also cause aqueductal stenosis (rare association)
What is gene is involved in Dravet syndrome?
SCN1A
