Epilepsy 2 Flashcards Preview

Medicine Phase 2a Neuro > Epilepsy 2 > Flashcards

Flashcards in Epilepsy 2 Deck (62)
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1
Q

Define

A

The recurrent tendency to spontaneous, intermittent, abnormal electrical activity in part of the brain, manifesting in seizures
Epilepsy is an ongoing liability to recurrent epileptic seizures
Chronic disorder

2
Q

Define epileptic seizure

A

Paroxysmal/unprovoked event in which changes of behaviour, sensation or cognitive processes are caused by excessive, hypersynchronous (unusually synchronised) neuronal discharges in the brain

3
Q

What are convulsions

A

Motor signs of electrical discharges

4
Q

Give example of an abnormal metabolic circumstance that would result in a seizure

A

Low Sodium

Hypoxia

5
Q

Since epilepsy is a chronic disorder, what does this mean for diagnosis

A

Need at least 2 seizures to be defined as epileptic

6
Q

Epidemiology

A

Common
Incidence is age-dependent, it is highest at the extremes of life with most cases starting before 20yrs or after the age of 60yrs
Canoften go into remission

7
Q

How long do epileptic seizures usually last

A

30-120 seconds

8
Q

How many epileptic seizures are idiopathic

A

2/3rds are idiopathic, often familial

9
Q

Aetiology - the 1/3 not idiopathic

A
Cortical scarring
Space-occupying lesion e.g. tumour
Stroke
Tuberous sclerosis
Alzheimer’s or dementia - epilepsy more common
Alcohol withdrawal
10
Q

Examples of cortical scarring that can cause epileptic seizures

A
  • Head injury years before onset
  • Cerebrovascular disease e.g. cerebral infraction or haemorrhage
  • CNS infection e.g. meningitis or encephalitis
11
Q

Risk factors

A
  • Family history
  • Premature born babies who are small for their age
  • Abnormal blood vessels in brain
  • Alzheimer’s or dementia
  • Use of drugs e.g. cocaines
  • Stroke/brain tumour/infection
12
Q

Elements of a seizure

A

Prodrome
Aura
Post-ictally (after seizure)

13
Q

What is prodrome and how long does it last

A

Lasting hours or days may rarely precede the seizure

Not part of the seizure, results in change of mood or behaviour

14
Q

What is aura

A

Part of seizure where the patient is aware and may precede its other manifestations
Strange feeling in the gut, deja vu or strange smells or flashing lights
(not necessarily due to temporal lobe damage)

15
Q

Describe post-ictally (after seizure)

A

Headache, confusion, myalgia and a sore tongue
Temporary weakness after a focal seizure in motor cortex - Todd’s palsy
Dysphasia following a focal seizure in the temporal lobe

16
Q

What is Todd’s palsy

A

Temporary weakness after a focal seizure in motor cortex

17
Q

Classifications of seizures

A
Primary generalised (40%)
Partial/focal seizures (57%)
18
Q

Describe Primary generalised seizure

A

Simultaneous onset of electrical discharge throughout whole cortex (involving both hemispheres), with no localising features referable to only one hemisphere
Bilateral symmetrical and synchronous motor manifestations
Always associated with loss of consciousness or awareness

19
Q

Describe partial/focal seziures

A

Focal onset, with features referable to a part of one hemisphere e.g. temporal lobe
Often seen with underlying structural disease
Electrical discharge is restricted to a limited part of the cortex of one cerebral hemisphere
These may later become generalised (e.g. secondarily generalised tonic-clonic seizures)

20
Q

Types of primary generalised seizures

A
Generalised tonic-clonic seizure
Typical absence seizure
Myoclonic seizure
Tonic seizure
Atonic (akinetic) seizure
21
Q

Describe the Tonic and Clonic phase of generalised tonic-clonic seizure

A

Tonic phase = Rigid, stiff limbs - person will fall to floor if standing
Clonic phase = Generalised, bilateral, rhythmic muscles jerking lasting seconds-minutes

22
Q

Describe clinical presentation of Generalised Tonic-Clonic seizure

A
Often NO aura
Loss of consciousness
Tonic and Clonic phase
Eyes remain OPEN
Tongue often bitten
May be incontinence of urine/faeces
23
Q

What follows a Generalised Tonic-Clonic seizure

A

period of drowsiness, confusion or coma for several hours post-ictally

24
Q

Describe clinical presentation of Typical Absence seizure

A
  • Usually a disorder of childhood
  • Child ceases activity, stares and pales for a few seconds only
  • I.e. suddenly stops talking in mid-sentence, then carries on where left-off
  • Often do not realise that they’ve had an attack
  • Children with petit mal tend to develop generalised tonic-clonic seizures in adult life
25
Q

How would you characterise a typical absence seizure

A

On EEG characterised by a 3-Hz spike and wave activity

26
Q

Clinical presentation of myoclonic seizure

A

Sudden isolated jerk of a limb, face or trunk

Patent may be thrown suddenly to the ground, or have a violently disobedient limb

27
Q

Clinical presentation of tonic seizure

A

Sudden sustained increased tone with a characteristic cry/grunt
Intense stiffening of body (tonic)
Stiffening NOT FOLLOWED by jerking

28
Q

Clinical presentation of atonic seizure

A

Sudden loss of muscle tone and cessation of movement resulting in a fall

29
Q

Examples of partial/focal seizures

A

Simple partial seizure
Complex partial seizure
Partial seizure with secondary generalisation

30
Q

Clinical presentation of Simple partial seizure

A

Not affecting consciousness or memory
Awareness is unimpaired with focal motor, sensory (olfactory, visual etc.), autonomic or psychic symptoms
No post-ictal symptoms

31
Q

Clinical presentation of Complex partial seizure

A
  • Affecting awareness or memory before, during or immediately after the seizure
  • Most commonly arise from the temporal lobe (understanding speech, memory & emotion)
  • Post-ictal confusion is common with seizures arising from the temporal lobe, whereas recovery is rapid after seizures in the frontal lobe (thought processing & movement)
32
Q

Clinical presentation of Partial seizure with secondary generalisation

A

In 2/3rds of patients with partial seizures, the electrical disturbance, which starts focally (as either a simple or complex partial seizure), SPREADS WIDELY causing a secondary generalised seizure which is typically convulsive

33
Q

Characteristics of partial/focal seizure depend on lobe affected.
Clinical presentation of partial seizure if temporal lobe affected

A

memory, emotion & speech understanding

Aura (80%) - Deja-vu, auditory hallucinations, funny smells, fear
Anxiety or out of body experience, automatisms e.g. lip smacking, chewing, fiddling

34
Q

Characteristics of partial/focal seizure depend on lobe affected.
Clinical presentation of partial seizure if frontal lobe affected

A

motor and thought processing

Motor features such as posturing or peddling movements of the
leg
Jacksonian march - seizure “marches” up or down the motor
homunculus starting in face or thumb
Post-ictal Todd’s palsy - paralysis of limbs involved in seizure for
several hours

35
Q

Characteristics of partial/focal seizure depend on lobe affected.
Clinical presentation of partial seizure if parietal lobe affected

A

Interprets sensations

Sensory disturbances - tingling/numbness

36
Q

Characteristics of partial/focal seizure depend on lobe affected.
Clinical presentation of partial seizure if occipital lobe affected

A

Vision

Visual phenomena e.g. spots, lines or flashes

37
Q

Functions of each lobe of cerebrum

A

Frontal - motor and thought processing
Temporal - memory, emotion & speech understanding
Parietal - interprets sensations
Occipital - vision

38
Q

What is syncope

A

loss of consciousness due to hypoperfusion to brain

39
Q

Difference in presentation between epilepsy and syncope

A

Epilepsy - Tongue biting, head turning, muscle pain, loss of consciousness, cyanosis, post-ictal symptoms
Syncope - Prolonged upright position e.g. long time standing, sweat prior to loss of consciousness, nausea, pre-syncopal symptoms

40
Q

Difference between epileptic and non-epileptic seizure

A

Non-epileptic seizures are situational
Non-epileptic is longer, closed mouth/eyes during tonic-clonic movements, pelvic thrusting, do not result from sleep, no incontinence or tongue biting
There are pre-ictal anxiety symptoms in non-epileptic seizure

41
Q

Differential diagnosis

A
Postural syncope
Cardiac Arrhythmia
TIA 
Migraine
Hyperventilation
Hypoglycaemia
Panic attacks
Non-epileptic seizure
42
Q

Clinical diagnosis

A

from history there needs to be at least 2 or more unprovoked seizures occurring > 24hrs apart to DIAGNOSE EPILEPSY

43
Q

Diagnosis

A
Electroencephalogram
MRI (imaging of hippocampus)
CT head
Blood tests - FBC, electrolytes, Calcium, Renal function, Liver function, Urine biochemistry, blood glucose levels
Genetic testing
44
Q

WHat is the purpose of of an electroencephalogram

A

Not diagnostic but can support a clinical diagnosis

May also help determine seizure type and what epilepsy syndrome

45
Q

What is the purpose of CT head

A

Rule out metabolic causes and discover comorbidities

46
Q

Give example of when genetic testing can be used

A

juvenile myoclonic epilepsy

47
Q

What are AEDs

A

Anti-Epileptic Drugs - help control seizures in about 70% of people

48
Q

Common types of Anti-epileptic drugs

A
sodium valproate
carbamazepine
lamotrigine
oxcarbazepine
ethosuximide
49
Q

Side effects of AEDs

A
drowsiness
a lack of energy
agitation
headaches
uncontrollable shaking (tremor)
hair loss or unwanted hair growth
swollen gums
rashes
50
Q

When would surgery be an option for treatment

A

AEDs aren’t controlling your seizures
Tests show that your seizures are caused by a problem in a small part of your brain that can be removed without causing serious effects

51
Q

What tests are done before surgery

A

Brain scans
Electroencephalogram - a test of your brains electrical activity
Tests of your memory, learning abilities and mental health

52
Q

Medical treatment of Generalised Tonic Clonic seizure

A

AEDs: Sodium valproate (not in child bearing age women); Lamtrigine
Seizure control: Diazepam (or Lorazepam)

53
Q

Medical treatment of Absence seizure

A

AED:
Sodium valproate
Ethosuximide

54
Q

Medical treatment of Partial seizure

A

AED: Lamotrigine carbamazepine; Phenytoin

Seizure control: Diazepam (or lorazepam)

55
Q

What other procedures can be done if AEDs aren’t controlling your seizures and brain surgery isn’t suitable for you

A

Vagus nerve stimulation (VNS)
Deep brain simulation (DBS)
Ketogenic diet

56
Q

What is Vagus Nerve Stimulation (VNS)

A

A small electrical device (similar to a pacemaker) is placed under skin of chest
A wire connects it to the vagus nerve and bursts of electricity are sent along the wire
Helps control seizures by changing electrical signals in brain

57
Q

Side effects of vagus nerve stimulation

A

Hoarse voice
Sore throat
Cough

58
Q

What is deep brain simulation and what are side effects

A

Similar to VNS
Wires run directly into brain
Bursts of electricity sent along these wires can help prevent seizures by changing the electrical signals in the brain

59
Q

1st line treatment of partial seizure

A

CARBAMAZEPINE

60
Q

What is SUDEP

A

Sudden unexpected death epilepsy

More common in uncontrolled epilepsy

61
Q

Treatment in emergency measures

A

Ensure patient harm themselves as little as possible - ABCDE
Check glucose
Prolonged seizure (longer than 3 minutes) or repeated seizures are treated with RECTAL/IV DIAZEPAM or LORAZEPAM - repeat x2
IV PHENYTOIN LOADING
If still fitting then anaesthetist involvement for anaesthetic and ventilation

62
Q

Generally drugs are NOT advised after just one fit, but when would you consider giving drugs anyway

A

If risk of recurrence is high