paediatric neurology - paroxysmal events

Question 1

define seizure/fit

Answer 1

any sudden attack from whatever cause

• lots of different mechanisms
  
  • many aren’t epileptic in nature

Question 2

define syncope

Answer 2

faint

neuro-cardiogenic mechanism

Question 3

define convulsion

Answer 3

seizure where there is prominent motor activity

Question 4

what is an epileptic seizure

Answer 4

electrical phenomenon

abnormal excessive hyper synchronous discharge from a group of cortical neurons

Question 5

effects of an epileptic seizure

Answer 5

may have clinical manifestations

paroxysmal change in motor, sensory or cognitive function

Question 6

what does the effect a seizure have depend on

Answer 6

seizure’s location

degree of anatomical spread over cortex

duration

Question 7

what is epilepsy

Answer 7

a tendency to recurrent, unprovoked (spontaneous) epileptic seizuires

Question 8

diagnosis of epilepsy

Answer 8

clinical features

EEG for supportive evidence

single seizure isn’t necessarily epilepsy

consequences of misdiagnosis can be serious

Question 9

types of non-epileptic seizures and seizure mimics in children

Answer 9

acute symptomatic seizures

reflex anoxic seizure

syncope

parasomnias e.g. night terrors

behavioural stereotypies

psychogenic non-epileptic seizures (PNES)

Question 10

what are acute symptomatic seizures

Answer 10

due to acute insults

e.g. hypoxia-ischaemia, hypoglycaemia, trauma

Question 11

what are reflex anoxic seizures

Answer 11

result of vagal overstimulation

common in toddlers

always provoked/triggered by certain stimuli e.g. fear, excitement, upset etc

Question 12

how does vagal overactivity result in reflex anoxic seizure

Answer 12

vagal activity → slows down heart

bradycardia → decreased cerebral perfusion

→ LOC and abnormal movements

Question 13

parasomnias as seizure mimics

Answer 13

e.g. night terrors

common in pre-school and early school age

can resemble epileptic sei`ures

Question 14

behavioural stereotypies as seizure mimic

Answer 14

intellectual disability

often have repetitive movements which are behavioural

Question 15

at what age do PNES occur

Answer 15

adolescents

Question 16

what are febrile convulsions

Answer 16

a seizure occuring in infancy/childhood

usually between 3mths and 5yrs of age

associated w/ fever but w/o evidence of intracranial infection or defined cause for the seizure

Question 17

how common are febrile convulsions

Answer 17

commonest cause of acute symptomatic seizure in childhood

Question 18

different seizure types

Answer 18

jerk/shake - clonic, myoclonic, spasm

stiff - tonic

fall - atonic, tonic, myoclonic

vacant attack - absence, complex partial seizure

Question 19

mechanism of epileptic fit - chemical trigger

Answer 19

decreased inhibition - GABA (gama-amino-butyric acid)

excessive excitation - glutamate and aspartate

excessive influx of Na and Ca ions

Question 20

how does chemical stimulation result in an epileptic seizure

Answer 20

chemical stimulation produces an electric current

summation of a multitude of electrical potentials results in depolarisation of many neurons which can lead to seizures - can be recorded from surface electrodes

Question 21

what are the 2 different seizure types on this EEG

Answer 21

partial and generalised

Question 22

what is a focal/partial seizure

Answer 22

seizure activity is restricted to one hemisphere/part of a hemisphere

Question 23

what is different about childhood vs adult onset epilepsies

Answer 23

• majority are idiopathic in origin - both focal and generalised
• majority of epilepsies and generalised
• seizures can be subtle - absences, myoclonus, drop attacks

Question 24

why is making a diagnosis of epilepsy challenging

Answer 24

• non-epileptic paroxysmal disorders are more common in children
• difficulty in explaining events
• difficulty in interpretation - witness
  
  • difficulty in interpretation and synthesising info - physician

Question 25

stepwise approach to diagnosis of epilepsy

Answer 25

1. is the paroxysmal event epileptic in nature 2. is it epilepsy 3. what seizure types are occurring 4. what is the epilepsy syndrome - certain types of epilepsy are more common at certain ages 5. what is the aetiology 6. what are the social and educational effects on the child

Question 26

EEG in epilepsy diagnosis- sensitivity

Answer 26

interictal EEG has limited value in deciding when the individual has epilepsy * sensitivity of first routine interictal EEF - 30-60%

Question 27

EEG in epilepsy diagnosis - false +ve rates

Answer 27

paroxysmal activity in 30% frankly epileptiform activity in 5% of normal children - will never have a seizure

Question 28

EEG in epilepsy diagnosis - when is it useful

Answer 28

useful in identifying seizure types, seizure syndrome and aetiology

Question 29

what is needed to diagnose epilepsy

Answer 29

* **hx** * **video recording** of event * **ECG** in convulsive seizures - rule out long QT syndrome which can be the cause of seizure * interictal/ictal **EEG** * **MRI** brain: determine aetiology - brain malformations/damage * **genetics**: idiopathic epilepsies are mostly familial, also single gene disorders e.g. tuberous sclerosis * **metabolic** tests: esp if associated w/ developmental delay/regression

Question 30

management of epilepsies in children

Answer 30

anti-epileptic drugs

Question 31

when should anti-epileptic drugs be considered

Answer 31

only if the diagnosis is clear even if this means delaying the treatment

Question 32

what is the role of AEDs

Answer 32

control seizures, not cure the epileptic

Question 33

choosing which AED to use

Answer 33

start with one - slow upward titration until side effects manifest or drug is considered to be inefficient age, gender, type of seizures and epilepsy should all be considered in selecting AEDs

Question 34

side effects of AEDs

Answer 34

CNS related SEs can be detrimental drowsiness, effect on learning, cognition and behavioual

Question 35

what drugs are first line for generalised epilepsies

Answer 35

sodium valproate (NOT IN GIRLS) or levetiracetam

Question 36

what is the first line drug for focal epilepsies

Answer 36

carbamazepine

Question 37

what new AEDs have more tolerability and fewer side effects

Answer 37

levatiracetam lamotrigine perampanel

Question 38

other therapies for epilepsy apart from AEDs

Answer 38

steroids immunoglobulins ketogenic diet * mostly for drug-resistant epilepsies sometimes considered for surgery

Question 39

when is epilepsy drug refractory

Answer 39

tried 2 different AEDs and still having seizures

Question 40

what are the 2 types of epilepsy surgery

Answer 40

curative palliative

Question 41

epilepsy surgery - vagal nerve stimulator

Answer 41

palliative lessens the burden of seizures on everyday life for the child sends electrical impulses to the L vagus nerve (afferent to the brain) - suppresses seizures effective in ⅓ of drug refractory epilepsy

Question 42

equipment in vagal nerve stimulator

Answer 42

programmable generator lead w/ 2 coils at the end hand-held magnet - can be used to set off pulse generator and terminate seizure

Question 43

resection for epilepsy

Answer 43

EEG on surface of brain to try and determine where the seizures are located may facilitate resection which can be curative