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Flashcards in Epilepsy Deck (93)
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1
Q

What is epilepsy?

A

A disease of the brain where there have been at least 2 unprovoked (or reflex) seizures >24 hours apart OR 1 unprovoked (or reflex) seizure alongside probability of further seizures

2
Q

What may suggest a high probability of further seizures in epilepsy?

A

Family history

3
Q

What it epilepsy NOT?

A

A single diagnosis (it is a symptom of many underlying causes)

4
Q

What is an epileptic seizure?

A

A transient occurrence of signs or symptoms due to abnormal electrical activity in the brain

5
Q

What types of signs or symptoms can occur in an epileptic seizure?

A
  • Altered consciousness
  • Disturbance of behaviour
  • Disturbance of emotions
  • Abnormal motor function
  • Abnormal sensation
6
Q

Is brain activity normally synchronous or non-synchronous?

A

Non-synchronous

7
Q

How is the electrical activity of the brain altered in epilepsy?

A

Groups of neurons begin to fire abnormally, excessively and in a synchronised manner resulting in a wave of depolarisation known as paroxysmal depolarising shift

8
Q

What is the underlying problem in neurons leading to excessive depolarisation in epilepsy?

A

Loss of resistance to firing soon after previous depolarisation

9
Q

What is thought to be the cause of the loss of depolarisation resistance in epilepsy?

A

Changes in ion channels or inhibitory neurons not functioning properly

10
Q

What results from the loss of resistance to depolarisation in a specific group of neurons in epilepsy?

A

A specific area call the seizure focus

11
Q

What factors are thought to bring on epileptic seizures?

A
  • Stress
  • Alcohol
  • Lack of sleep
  • Flickering lights
  • Others
12
Q

What is meant to by seizure threshold?

A

The amount of stimulus needed to induce a seizure

13
Q

What happens to the seizure threshold in epilepsy?

A

It is lowered

14
Q

What is the underlying cause of most cases of epilepsy?

A

Idiopathic

15
Q

What are some less common underlying causes of epilepsy?

A
  • Cerebrovascular disease
  • Head injury
  • Cranial surgery
  • CNS infections
  • Neurodegenerative disease
  • Autoimmune disease
  • Genetic diseases
  • Drugs
  • Metabolic disorders
  • Alcohol binge drinking or withdrawal
16
Q

What cerebrovascular disease can lead to epilepsy?

A
  • Cerebral infarction
  • Cerebral haemorrhage
  • Venous thrombosis
17
Q

What CNS infections can result in epilepsy?

A
  • Meningitis

- Encephalitis

18
Q

What neurodegenerative disease can result in epilepsy?

A
  • Alzheimer’s

- Multi-infarct dementia

19
Q

What drugs can cause epilepsy?

A
  • Phenothiazides
  • Isoniazids
  • TCA’s
  • Benzodiazepines
20
Q

What metabolic disorders can cause epilepsy?

A
  • Uraemia
  • Hypoglycaemia
  • Hyponatraemia
  • Hypernatraemia
  • Hypercalcaemia
  • Hypocalcaemia
21
Q

What are the risk factors for epilepsy?

A
  • Family history
  • Small for gestational age
  • Seizures in first month of life
  • Serious brain injury or hypoxia
  • Cerebral palsy
  • Developmental disabilities
  • Febrile seizures
22
Q

How can epilepsy be classified?

A
  • Description of seizure
  • Seizure type
  • Epilepsy syndrome
  • Aetiology
23
Q

Why is it important to classify epilepsy correctly?

A

Incorrect classification can lead to in appropriate treatment

24
Q

What can result from inappropriate treatment of epilepsy?

A

Persistent seizures

25
Q

How can epileptic seizures be broadly classified?

A

By region affected

26
Q

What are the two classifications of epileptic seizures based on area affected?

A
  • Focal seizures

- Generalised seizures

27
Q

What are focal seizures?

A

Seizures originating in a limited part of the brain that can remain localised or spread to be more widely distributed in one hemisphere

28
Q

What were focal seizures previously known as?

A

Partial seizures

29
Q

What are the subtypes of focal seizure?

A
  • Focal aware seizure

- Focal impaired awareness seizures

30
Q

What are focal aware seizures?

A

Seizures only affecting a small region of the brain with retained awareness

31
Q

What areas of the brain are commonly affected in focal aware seizures?

A
  • Temporal lobe

- Hippocampus

32
Q

What were focal aware seizures previously known as?

A

Simple partial seizures

33
Q

What are focal impaired awareness seizures?

A

Seizures with impaired awareness usually with total unilateral hemisphere involvement

34
Q

Where do focal impaired awareness seizures arise most commonly?

A

Medial temporal lobe

35
Q

What is it called if a focal seizure progresses to become a generalised seizure?

A

Secondary generalised seizure

36
Q

What happens in a secondary generalised seizure?

A

Discharge starts in one area and then spreads to both hemispheres

37
Q

What is a generalised seizure?

A

A seizure where there is impaired consciousness and distorted electrical activity in the whole or a large part of both hemispheres

38
Q

What are the 2 categories of symptom types seen in generalised seizures?

A
  • Convulsive

- Non-convulsive

39
Q

What are the different types of generalised seizures?

A
  • Absence
  • Myoclonic
  • Clonic
  • Tonic-clonic
  • Atonic
40
Q

When is epilepsy classed as unclassified?

A

When no adequate description of seizures is available

41
Q

What happens to consciousness in simple focal seizures?

A

It is unaffected

42
Q

What are some common symptoms of people having a simple focal seizure?

A
  • Sudden inexplicable emotions
  • Sensations of falling or moving
  • Unusual sensations
  • Altered special senses
  • Deja vu or jamais vu
  • Laboured speech
43
Q

What happens to consciousness in complex focal seizures?

A

It is altered

44
Q

How may consciousness be affected in complex focal seizures?

A
  • Loss of consciousness
  • Confusion
  • Unable to respond
45
Q

What do symptoms of complex focal seizures depend on?

A

Part of the brain that is affected

46
Q

What are the symptoms of temporal lobe complex focal seizures?

A
  • Picking up objects for no reason
  • Chewing or lip-smacking
  • Muttering or repeating words
  • Wandering around in confusion
47
Q

How long do temporal lobe complex focal seizures generally last?

A

2-3 minutes

48
Q

What are some symptoms of frontal lobe complex focal seizures?

A
  • Making loud crys or screams
  • Making strange postures
  • Making cycling or kicking movements
49
Q

How long do frontal lobe complex focal seizures generally last?

A

15-30 seconds

50
Q

What can happen in parietal and occipital complex focal seizures?

A

Abnormal vision or sensations

51
Q

How long do parietal and occipital complex focal seizures generally last?

A

15-30 seconds

52
Q

What often precedes a complex focal seizure?

A

An aura

53
Q

How can a pre-seizure aura maifest?

A
  • Deja vu or jamais vu
  • Fear
  • Euphoria
  • Depersonalisation
  • Visual disturbance
54
Q

What is the period after a seizure known as?

A

Post-ictal period

55
Q

What can often happen in the post-ictal period of a complex focal seizure?

A
  • Confusion

- Tiredness

56
Q

How do absence seizures present?

A
  • Vacant and unresponsiveness

- Slight muscle twitching

57
Q

How long do absence seizures usually last?

A

Up to 30 seconds

58
Q

What is another name for an absence seizure?

A

Petit mal seizure

59
Q

What happens in a myoclonic seizure?

A

Extremely brief (<0.1 second) muscle contraction resulting in a jerky movement of muscle or muscle groups

60
Q

What happens in a clonic seizure?

A

Regularly repeating (every 2-3 seconds) myoclonic movements

61
Q

What happens in a tonic-clonic seizure?

A
  • Initial tonic phase with contraction of msucles

- Clonic phase of rhythmic contractions

62
Q

What may accompany the initial tonic phase in tonic-clonic seizures?

A
  • Tongue biting
  • Urinary incontinence
  • Absence of breathing
63
Q

What happens in atonic seizures?

A

Loss of muscle tone causing person to fall to the ground

64
Q

What blood tests can be appropriate in trying to identify causes or differentials of epilepsy?

A
  • Glucose
  • Electrolytes
  • Calcium
  • Renal function
  • Liver function
  • Urine biochemistry
65
Q

When is an EEG useful in epilepsy?

A
  • To support a diagnosis

- To help determine the type and origin of seizure

66
Q

When should EEG not be used in epilepsy?

A

To make a diagnosis

67
Q

If a standard EEG is not helpful what could be considered?

A

Sleep EEG

68
Q

If after standard EEG and clinical assessment, diagnosis is not certain what can be used?

A

Long-term video or ambulatory EEG

69
Q

What is neuro-imaigng useful for in epilepsy?

A

Identifying structural abnormalities that can cause epilepsy

70
Q

What is the imaging modality of choice in epilepsy?

A

MRI

71
Q

When is MRI particularly important in epilepsy?

A
  • Patient has focal onset

- Seizures continue despite first-line medication

72
Q

What investigation can be performed at home in epilepsy?

A

Handheld video recording

73
Q

When is a neuropsychological assessment indicated in epilepsy?

A
  • Person has educational or occupational difficulties
  • MRI identifies abnormality in cognitively important areas of the brain
  • Reported cognitive defecits
74
Q

What are some important differentials for epileptic seizures?

A
  • Syncope
  • Cardiac arrhythmias
  • TIA
  • Migraine
  • Acute encephalopathy
  • Sleep disorders such as narcolepsy
  • Panic attacks
  • Non-epileptic seizures
75
Q

When should anti-epileptic drug therapy be started?

A

Only once diagnosis is confirmed (except exceptional cases)

76
Q

What should be taken into account when starting a patient on anti-epileptic drugs (AEDs’)?

A
  • Risks
  • Benefits
  • Epilepsy syndrome
  • Prognosis
  • Lifestyle
77
Q

Should AED’s be used in combination?

A

Only if monotherapy with multiple AED’s fails

78
Q

If an AED monotherapy fails to control seizures or causes side-effects how should the next one be started?

A

Alongside the old one and then once adequate dose is reached taper off the old one

79
Q

Give 4 examples of AED’s?

A
  • Carbamazepine
  • Lamotrigine
  • Phenytoin
  • Sodium valproate
80
Q

Why should caution be taken prescribing AED’s in women of child bearing age?

A

They are highly teratogenic

81
Q

What must you be vigilant for in patients on AED’s?

A

Adverse effects

82
Q

How can adherence to AED therapy be optimised?

A
  • Educate patients
  • Reduce stigma associated with epilepsy
  • Use simple regimes
  • Develop a positive relationship with the patient and their family
83
Q

When may withdrawal of AED’s be considered?

A

After discussion of risks and benefits and after at least 2 years seizure free

84
Q

How long should withdrawal of AED’s be conducted?

A

2-3 months

85
Q

Withdrawal of what drugs used to treat epilepsy should extra care be taken?

A

Benzodiazepines and barbiturates

86
Q

What adjunctive therapies may be useful in epilepsy?

A
  • Psychological interventions
  • Vagus nerve stimulation
  • Surgery
87
Q

What are the disadvantages of psychological interventions in epilepsy?

A

They have not been proven to affect seizure threshold

88
Q

What sort of psychological therapies can be used in epilepsy?

A
  • Relaxation
  • CBT
  • Biofeedback
89
Q

What can vagus nerve stimulation do in epilepsy?

A

Reduce seizure frequency in refractory cases not suitable for surgery

90
Q

Which epilepsy patients is surgery indicated for?

A

Focal refractory epilepsy

91
Q

What are the most common surgical procedures in epilepsy?

A

Anterior and medial temporal lobe resction

92
Q

What % of patients with refractory focal epilepsy undergoing anterior and medial temporal lobe restction are seizure free post-op?

A

70%

93
Q

What are the potential complications of epilepsy?

A
  • Social stigmatisation
  • Occupational issues
  • Psychological problems
  • Developmental problems in children
  • Accidents
  • Status epilepticus