Seizures and Epilepsy

Question 1

Seizure definition

Answer 1

Sudden synchronous discharge of cerebral neurons causing symptoms or signs that are apparent to either the patient or an observer

Question 2

Epilepsy definition

Answer 2

Neurological disorder that causes repeated seizure activity

Question 3

What are the two types of seizures

Answer 3

Focal and Generalised

Question 4

What is a focal seizure caused by?

Answer 4

An electrical discharge restricted to a limited part of the cortex of one cerebral hemisphere

Question 5

How are focal seizures classified?

Answer 5

Aura (smell, auditory hallucinations, deja vu)
Loss of awareness or responsiveness
Motor features (eg. One limb jerking)

Question 6

What is a generalised seizure caused by?

Answer 6

Simultaneous involvement of both hemispheres, there is always loss of consciousness or responsiveness involved

Question 7

Aetiology of seizures

Answer 7

Vascular (ischaemic stroke, intracranial haemorrhage, SAH, anoxic brain injury)
Infectious (meningitis, encephalitis, abscess)
Traumatic (epidural or subdural haemorrhage)
Autoimmune (SLE, paraneoplastic syndrome)
Metabolic (decrease B1, kidney, liver, thyroid)
Idiopathic (anti-epileptic meds)
Neoplastic (meningioma, Glioblastoma multiforme)

Drugs (OTIS CAMPBELL)
+
Eclampsia/ everything else

Question 8

OTIS CAMPBELL (drugs causes of seizures)

Answer 8

Opioids (diamorphine)
Tricylic antidepressants
Isoniazid (TB)
Salicylate

Cocaine
Anti-emetic (prochlorperazine)
Metronidazole
Penicillin
Benzodiazepine withdrawal
Ethanol (alcohol) withdrawal
Lithium

Question 9

Pathophysiology of a seizure

Answer 9

An imbalance between the excitatory and inhibitory signals in the brain

Question 10

types of generalised seizures

Answer 10

Tonic-Clonic (grand mal)
Myoclonic
typical absence seizures
Tonic
Atonic

Question 11

Presentation of a Tonic Clonic seizure (grand mal)

Answer 11

prodrome -
usually no warning prior to the onset, in bilateral tonic Clonic seizures there may be aura present

Ictal phase -
initial tonic stiffening, then synchronous ‘jerking’ of the limbs
Reducing in frequency over 2 mins
May be an initial cry when patient falls
Eyes open and tongue sometimes bitten
Faecal and urinary continence can occur
Patient unaware of the experience

Post Ictal phase -
Flaccid unresponsiveness and then patient slowly gains consciousness and awareness 15 mins to 1 hr

Question 12

Presentation of a typical absence seizure

Answer 12

Usually begins in childhood
Loss of awareness and vacant facial expression for < 10 seconds
3Hz spike and wave on ECG activity

Question 13

Presentation of a Myoclonic seizure

Answer 13

Myoclonic seizure or ‘jerks’ take the form of momentary brief contractions of a muscle (eg. Twitch of finger or hand or larger muscle groups)
Common in primary generalised epilepsies

Question 14

Presentation of a Tonic seizure

Answer 14

Stiffening of the body, not followed by ‘jerking’

Question 15

Presentation of an Atonic seizure

Answer 15

Involve sudden collapse with loss of muscle tone and consciousness

Question 16

Types of focal seizures

Answer 16

FOCAL SEIZURES WITH AURA
FOCAL SEIZURES WITH ALTERED AWARENESS
FOCAL MOTOR SEIZURES

Question 17

types and Clinical presentation of a focal seizure with aura

Answer 17

Temporal lobe seizure : auditory or olfactory hallucinations, deja vu or jamais vu, fear, abdominal rising sensation, nausea + vertigo

Frontal lobe seizure : conjugate gaze deviates away from epileptic focus and head turns

Occipital lobe seizure : visual phenomena (zig-zag lines, coloured scotoma)

Question 18

Clinical presentation of focal motor seizure

Answer 18

Originates with in the motor cortex
‘Jerking’ typically begins one side of mouth or hand and sometimes spread
This visual spread of movement is called the Jacksonian March
Todd’s paralysis sometimes follows: local temporary paralysis of limbs affected

Question 19

Clinical presentation of focal seizure with altered awareness

Answer 19

Often temporal or frontal lobe
Often aura preceding and the total or partial loss of consciousness for 1-2 minutes which patient does not remember
Can be followed by speech arrest and often automatism (stereotyped talking or moving (lip-smacking or even taking off clothes)

Question 20

Types of Primary Generalised Epilepsy

Answer 20

Childhood Absence Epilepsy
Juvenile Myoclonic Epilepsy
Monogenic disorders

Question 21

What is status epilepticus

Answer 21

a single seizure lasting >5 minutes, or
>= 2 seizures within a 5-minute period without the person returning to normal between them

Question 22

Clinical features of a Febrile convulsion

Answer 22

usually occur early in a viral infection as the temperature rises rapidly
seizures are usually brief, lasting less than 5 minutes
are most commonly tonic-clonic