Epilepsy & Seizures

Question 1

What can cause a blackout? [5]

Answer 1

• Vasovagal Syncope
• Hypoxic Seizure
• Concussive Seizures
• Cardiac Arrhythmia
• Non-epileptic attacks

Question 2

Define Vasovagal syncope [3]

Symptoms [5]

Answer 2

Syncope may be defined as a transient loss of consciousness [1] due to global cerebral hypoperfusion [1] with rapid onset, short duration and spontaneous complete recovery [1].

• Light headed
• Nausea
• Hot/Sweating
• Tinnitus
• Tunnel Vision

Question 3

What could trigger vasovagal syncope? [5]

Answer 3

• Prolonged Standing or standing up too fast
• Trauma
• Venepuncture
• Urination
• Coughing

Question 4

Whats the difference between a seizure and syncope?

Answer 4

• Syncope tends to happen when your upright
• Pallor is common in syncope
• Syncope has a gradual onset vs a sudden onset seizure
• Injury & incontinence are rare in syncope
• Recover rapidly from syncope but not seizure
• Syncope is triggered, precipitants for seizures are rare

Question 5

How does a hypoxic seizure occur? Which setting would this most commonly occur? [2]

Answer 5

People who faint and then are kept upright keep fainting and dont breath –> Seizure

Occurs a lot in aircraft where people cant end up lying down

Question 6

What is a non-epileptic attack? [1]
Gender epidemiology [1]
Links [3]
Management [1]

Answer 6

F > M
‘pseudoseizures’

They are often linked to:

• Stress
• Past abuse
• History of medically unexplained symptoms

Require psychological input not AEDs

Question 7

When you have a patient who blacked out what do you want to know?

Answer 7

• What they were doing
• Any warning feelings or Aura
• Similar previous history
• Any injury or incontinence
• How responsive are/were they, what collour did they go, did they move or make sound
• Whats their pulse like
• Past medical, psych, alcohol/drug and family history

Question 8

If someone’s had their first seizure how would you investigate? [4]

Answer 8

• Bloods - metabolic causes e.g., hyponatraemia
• Brain imaging
• CSF exam if systemic illness - HSV, autoimmune encephalitis
• EEG
• Advanced functional imaging can localise seizure focus

Question 9

What features on a first seizure would suggest generalized epilepsy [3]
What features on a first seizure would suggest focal epilepsy [3]

Answer 9

Primary Generalised Epilepsy:

• History of myoclonic jerks (particularly in morning)
• Absences
• Feeling strange +/- flickering lights

Focal Onset Epilepsy:

• Deja Vu
• Rising in abdomen
• Episodes where they look blank and smack lips

Question 10

How would you advise someone who’s just had their first seizure? [3]

Answer 10

• Driving Regulations
• Inquire about employment or potentially dangerous activities
• Refer to epilepsy clinic for routine follow up

Question 11

Define Epilepsy [3]

Answer 11

• A neurological disorder marked by sudden recurrent episodes [1] of sensory disturbance, loss of consciousness, or convulsions, [1] associated with abnormal electrical activity in the brain. [1]
• Caused by predisposition to neuronal hyperexcitability

Question 12

Epilepsy epidemiology [1]

Causes of epilepsy [5]

Answer 12

More common in extremes of age

1. 6 in 10 unknown cause
2. Difficult birth
3. Brain infection
4. Stroke
5. Serious brain injury

Question 13

In what groups is epilepsy more common? [1]

Answer 13

People with learning difficulties (22% of people with LD)

Question 14

What are the classifications of Epilepsy [2]

Answer 14

Generalised Epilepsy (metabolic causes)
Focal Epilepsy (structural abnormalities)

Question 15

What are the types of Primary Generalised Epileptic Seizure [6]

Answer 15

• Tonic Clonic (Tense-Jerky)
• Myoclonic (Very brief twitch contractions)
• Clonic
• Tonic
• Atonic (Very rapid collapse to floor)
• Absence (most common in kids, tends to grow out by age 12)

Question 16

How are focal onset seizures different? [2]
Name the 3 subtypes
In which type of seizure classification is family history relevant? [1]

Answer 16

They vary by which area of the brain is affected. May come with aura which may localise where the seizure is happening in the brain.

They may retain awareness/responsiveness (Simple) OR may have impaired awareness (Complex)

Can develop into a secondary generalized seizure
called ‘Focal to Bilateral seizure’ or secondary generalized seizure

Family history association in generalized but not in focal epilepsy

Question 17

How does an EEG change between focal/partial and generalized epileptic seizures?
What could an MRI/CT show us to differentiate between focal and generalized?

Answer 17

An EEG would show generalised vs focal abnormalities of brain waveform

An MRI or CT may show a physical cause in a focal epileptic but not primary generalised

Question 18

How would you make epilepsy visible in order to test with an EEG? [3]

Answer 18

Hyperventilation
Photic Stimulation
Sleep Deprivation

Will show up best in Generalised Epilepsy

Question 19

What other test can be done for epilepsy if you didn’t find anything on EEG? [2]

Answer 19

Video-Telemetry

Basically an EEG with a camera over several days

Question 20

What are the rules for driving with epilepsy?

Answer 20

Normal licenses:

• Seizure Free for a year Or had seizures but only from sleep.
• If you have a daytime seizure ever then you will need 3 yrs of none or purely nocturnal seizures

HGV/PSV:
- Seizure and medication free for 10yrs

Question 21

Side effects of Sodium valproate [4] and Carbamezapine [4]?

Answer 21

Sodium Valproate:

• Tremor/Ataxia
• Weight Gain
• Hair Loss
• Pancreatitis/Hepatitis

Carbamazepine:

• Ataxia
• Low Serum Na
• Severe Skin rash
• Nystagmus/Blurred Vision

Question 22

What is Status Epilepticus? [1]
Whats the most common type?
Aetiology [4]
Sequelae [1]

Answer 22

A prolonged or recurrent seizure that lasts for 5 mins with no recovery period in between

(Most common type is TCSE - Tonic Clonic Status Epilepticus)

Usually caused by stroke, tumour, haemorrhage or alcohol and 90% of deaths are due to the underlying cause not the seizure itself

Can lead to neuro problems (brain damage) in children

Question 23

How do we treat TCSE?

Answer 23

1st line - IV lorazepam 4mg, midazolam buccal/IM/IV, diazepam oral/rectal/IV.
2nd line - Phenytoin slow infusion 15-18mg/kg at 50mg/min
3rd line - GA e.g. propofol

NPA airways may be more practical than oral airways.

Question 24

Alternative uses for carbamazepine [1]

Answer 24

As well as being an anticonvulsant it treats nerve pain in conditions such as Trigeminal Neuralgia

Question 25

Partial seizure Frontal lobe seizures State 2 types Explain Todd's paralysis [1]

Answer 25

Jacksonian motor seizures - 'march' of involuntary movement from one muscle group and then spreads [1] Adverse seizure - patient's eyes and head turn away from the site of the focal origin [1] Todd's paralysis is common after motor seizure - affected limb remains weak for some hours after [1]

Question 26

Partial seizure Point of origin in cortex [1] Parietal lobe seizures Presentation [2]

Answer 26

Arising in sensory cortex Paresthesia in extremity or on face Distortion of body image

Question 27

Why are frontal and parietal seizures indicate structural brain disease

Answer 27

Frontal and parietal seizures indicate structural brain disease

Question 28

# Localisation of features of focal seizures Partial seizure | Temporal lobe seizure

Answer 28

Visceral disturbance: taste, smell hallucinations, lip smacking, epigastric fullness, choking sensation Memory disturbance: deja vu, jamais vu (unfamiliarity), depersonalization Motor disturbance: fumbling movement, rubbing, chewing Affective disturbance: displeasure, elation, fear

Question 29

Partial seizure | Occipital lobe seizure

Answer 29

Visual hallucination eg line or flash | Tonic clonic seizure

Question 30

Explain underlying pathogenesis of secondary generalized seizures [2] Why is there a risk of death in these type of seizures? [1]

Answer 30

Seizure discharges have capacity to spread from point of origin and excite deeper subcortical structures eg thalamus Their excitation releases discharge spreading back to both hemispheres Sudden death may occur (rare) from cardiac arrhythmia

Question 31

Absence seizures Main features [2] Frequency [1] Trigger [2] Management [2] Prognosis

Answer 31

The patient (3-10 y/o stares vacantly, eyes may blink, 'petit mal' Many times a day with duration 5-15s No awareness Trigger: hyperventilation, photic stimulation Mx: sodium valproate and ethosuximide are first-line treatment Prognosis: good prognosis - 90-95% become seizure free in adolescence

Question 32

Generalized tonic-clonic seizures Main features [2] Explain why there are 2 phases Describe typical history from a secondary generalized seizure [5]

Answer 32

Occur without warning or aura, ALL unconscious Tonic phase associated with rapid neuronal discharge Clonic phase begins as neuronal discharge slow ``` LOC > fall to ground Tonic phase 10s Clonic phase 1-2 min Unrousable sleep, stertorous respiration Muscle ache, exhaustion post-ictal ```

Question 33

Triggers for epilepsy [7]

Answer 33

``` Forgetting epilepsy medicine Feeling tired, stressed Sleep deprivation Alcohol Photic stimulation Menstruation Missing meals ```

Question 34

MOA of sodium channel blockers ie the anticonvulsants on epilepsy Give examples [5]

Answer 34

Sodium channel blockers reduce opportunity for depolarisation * Phenytoin * Carbamazepine * Lamotrigine * Lacosamide * Rufinamide

Question 35

Name other drugs that are used in epilepsy (besides sodium channel blockers) [4]

Answer 35

GABA-receptor agonist T-type CCB ie ethosuximide Glutamate blocker Levetiracetam

Question 36

Give examples of a GABA receptor agonist [2]

Answer 36

Lorazepam | Valproate

Question 37

Give an example of a glutamate blocker [1] | Which group of patients are they well suited to

Answer 37

Topiramate | Obese patients as weight loss inducing effect

Question 38

# Epilepsy Give 4 example of an anti-epileptic that works on calcium channels

Answer 38

Ethosuximide Lamotrigine Topiramate Gabapentin

Question 39

Give an example of an anti-epileptic that works on potassium channels

Answer 39

Direct activation limits the firing of action potentials by hyperpolarising the neural membrane.

Question 40

Give an example of an anti-epileptic that works on potassium channels

Answer 40

Direct activation limits the firing of action potentials by hyperpolarising the neural membrane. Retigabine

Question 41

Give an example of an anti-epileptic that works on potassium channels

Answer 41

Direct activation limits the firing of action potentials by hyperpolarising the neural membrane. Retigabine

Question 42

Give an example of an anti-epileptic that works on potassium channels

Answer 42

Direct activation limits the firing of action potentials by hyperpolarising the neural membrane. Retigabine

Question 43

Secondary epilepsy Name 5 recognised insults

Answer 43

* Metabolic, e.g. electrolyte/glucose disturbance. * Infectious, e.g. meningitis, encephalitis. * Autoimmune, e.g. vasculitis, limbic encephalitis, Rasmussen’s encephalitis (affecting a single cerebral hemisphere and characterised by frequent and severe seizures, hemiparesis, encephalitis and dementia). * Cerebral structural damage: lowers seizure threshold.

Question 44

Identify 3 mechanisms of cerebral structural damage that lower seizure threshold: This is why we give prophylactic keppra for 10 days in some patients.

Answer 44

Surgery, trauma, subarachnoid/subdural haemorrhage, abnormal vasculature, e.g. AVM, cavernoma: - blood is particularly epileptogenic, especially when it contacts the cortical surface. Tumours: benign and malignant, whether primary or metastatic. Demyelination.

Question 45

Give an example of an anti-epileptic that works on potassium channels

Answer 45

Direct activation limits the firing of action potentials by hyperpolarising the neural membrane. Retigabine

Question 46

Give an example of an anti-epileptic that works on potassium channels

Answer 46

Direct activation limits the firing of action potentials by hyperpolarising the neural membrane. Retigabine

Question 47

Give an example of an anti-epileptic that works on potassium channels

Answer 47

Direct activation limits the firing of action potentials by hyperpolarising the neural membrane. Retigabine

Question 48

# First line anti-epileptics Generalised seizures: Tonic clonic Absence Myoclonic Tonic/atonic

Answer 48

All sodium valproate

Question 49

# First line anti-epileptics Focal seizures

Answer 49

Carbamazepine or lamotrigine

Question 50

# Management of epilepsy in pregnancy Which anti-epileptics are contraindicated in pregnancy? Which anti-epiletics are used in pregnancy?

Answer 50

* Sodium valproate is most strongly associated with malformations and neurodevelopmental problems and, as such, should be a drug of last resort in fertile women. * Phenytoin, carbamazepine and phenobarbital are all associated with a significantly increased risk of teratogenicity - older anti-epileptics * Lamotrigine has been well studied in pregnancy and, although it does still carry a small dose-dependent risk to the fetus, is generally the medication of choice. * Levetiracetam has less extensive pregnancy data, but appears to be safe.

Question 51

# Management of epilepsy in pregnancy What is important in the use of lamotrigine during pregnancy in terms of pharmacokinetics Other medications you must ensure pregnant epileptic women is taking

Answer 51

* Pregnancy can reduce serum lamotrigine levels, and these should therefore be monitored and the dose increased when necessary. * All women with epilepsy should be given daily folic acid during the preconception period and while pregnant to reduce the risk of neural tube defects. * Many anti-epileptic drugs induce infantile vitamin K deficiency, and the neonate should receive supplementation at birth and again at 28 days.

Question 52

Give an example of an anti-epileptic that works on potassium channels

Answer 52

Direct activation limits the firing of action potentials by hyperpolarising the neural membrane. Retigabine

Question 53

Classification of Epilepsy What are the 3 broad categories? How is focal seizure classified?

Answer 53

Question 54

Alcohol withdrawal | symptoms, pathophysiology, treatment

Answer 54

* can occur in patients who abruptly stop or significantly reduce their alcohol consumption. * tremors, anxiety, insomnia, and seizures. * pathophysiology of alcohol withdrawal involves changes in the brain's neurotransmitter systems- gamma-aminobutyric acid (GABA) and glutamate. * Treatment typically involves benzodiazepines (chlordiazepoxide), which enhance GABA activity and help to prevent seizures and other complications.