NEURO - Epilepsy Flashcards
Define:
- ictus
- seizure
- epilepsy
- Ictus: Sudden neurological event
- Seizure: Abnormal, hypersynchronous neural activity
- Epilepsy: Tendency to repeated, spontaneous seizures
Common seizure types
- (3) generalised
- (2) focal
Generalised
•Generalised Tonic-Clonic (GTCS)
•Absence
•Myoclonus
Focal
•Dyscognitive
•Evolving to a bilateral, convulsive seizure (Secondarily generalised)
Discuss generalised tonic clonic seizure
- 2 phases
- duration
- injury
- post event
- Tonic phase: Arms down, Eyes open, Cry
- Clonic phase
- Apnoea: Cyanosis or plethora
- Last 1-5 minutes
- Minor injury common: Tongue biting
- Aftergoing confusion: Wake up in the ambulance or ED
Describe absence (generalised) seizure
- Px
- duration
- epidemiology
- Alteration of consciousness: Stay upright, No warning, Difficult to detect
- Facial twitch: 3Hz Blink, Oral myoclonias, Eyes often drift open
- Last 2-10 seconds
- Present in children or teenagers
Describe myoclonus (generalised) seizure - Px
- Sudden, involuntary muscle twitch
- Not specific to seizure: Sleep myoclonus, Common in metabolic encephalopathy
- Myoclonic seizures: Action related, Appear as prodrome to GTCS
Describe focal seizures
- area of brain
- consciousness involvement
- Px depending on location
- duration
•Single area of brain •Without alteration of consciousness •Features depend on location - Temporal – Smell, deja-vu - Motor strip – Localised clonus - Occipital – Visual hallucinations etc...
•Usually brief
Describe focal dyscognitive seizures
- area of brain
- consciousness involvement
- comparison to absence seizure
- Localised region
- Affects consciousness: Bilateral temporal lobes involved
•Similar to absence but…
- Longer
- Less distinct offset
- Automatisms
- Less frequent
- Preceding simple seizure
Describe childhood absence epilepsy (Petit Mal)
- onset
- seizure types
•Onset 4-8 years, up to 12
Seizure types
–Absence seizures: Frequent - many / day
–Generalized Tonic-Clonic Seizures: 40%, Adolescence
Describe juvenile absence epilepsy
- onset
- seizure types
•Onset: adolescence
•Seizure types
–Generalized Tonic-Clonic Seizures
–Absence seizures: infrequent, Absence Status
Describe juvenile myoclonic epilepsy (Janz)
- onset
- seizure types
- other associated features
- prognosis
•Onset 12 - 18 years •Seizure types –Myoclonus –GTCS (general tonic clonic seizure) –Absences in 30% •Photosensitive •Sleep-wake cycle •May evolve from CAE •Prognosis –Not often refractory –Spontaneous remission rare
Difference between seizure type & epilepsy syndrome
Seizure type:
- clinical characteristics (Seizure, pts)
- EEG features
Epilepsy syndrome:
- seizure types
- age
- clinical course
- interictal EEG
- MRI
(3) DDx of a seizure
- Syncope
- TIA
- Psychogenic pseudoseizure
Discuss syncope
- causes
- Px
•Cause: Insufficient cerebral blood flow
- Neurocardiogenic
- Orthostatic
- Cardiac
•Collapse and LOC
- Convulsion
- Urinary incontinence
Hx of a syncope
- before
- during
- after
Before:
- predisposition
- trigger
- pre-syncope (prodrome)
During:
- Px
- convulsion?
- other associated features to DDx causes of syncope/seizure
After:
- recovery
- confusion?
(5) Typical predispositions of syncope
- Dehydration
- Anti-hypertensives
- Prolonged standing
- Stressful situation
- Recent awakening
(4) Triggers of syncope
- Emotional
- Valsalva
- Pain
- Postural change
(3) pre-syncope Px (prodromes)
•“Dizziness” •Feeling of distance •Visual disturbance –Silver flickers –Greying of vision
(3) Predisposition & triggers of seizure
–Sleep deprivation
–Hang-over or abrupt abstinence
–Flicker
What (2) medications can induce seizures?
–Clozapine
–Tramadol
What should you ask in a syncope pt?
•Previous syncope and presyncope
•Recent medication changes
•Drugs
–Amphetamines
Features of psychogenic pseudoseizure
- Fluctuating intensity
- Very long
- Eyes closed: Pseudo-sleep
- Non-anatomical tremor
- Reactive
- Consciousness retained: Usually denied
Difference between epilepsy & seizure
Epilepsy is a disorder characterized by recurring seizures (also known as “seizure disorder”)
A seizure is a brief, temporary
disturbance in the electrical activity of the brain
Comment on ictal & interictal EEG
Ictal EEG:
•Almost always abnormal in seizure
•Perfect for pseudoseizure
Interictal EEG:
•Diagnostic test for epilepsy, not seizure
–Prognosis
–Epilepsy syndrome diagnosis
•Most abnormal patterns also seen in normals
–Normal patterns often interpreted as abnormal
Prognosis of single seizure presentation
- % recurrence at one year
- % recurrence long term
- Most recurrence early
- 40% recur at one year
- Just over 50% long term
Can early treatment change prognosis in seizures?
–Better early seizure freedom if treated early
–BUT By five years outcome identical
Is not treating the first seizure dangerous?
No.
Only elevated due to underlying condition
Recurrent seizures not a big mortality risk
How do you diagnose epilepsy?
- History of minor seizures: Focal, Myoclonus
- Await recurrence
- Epileptiform EEG
- Epileptogenic MRI lesion
What should you educate the pt on with diagnosis of epilepsy?
Safety •Swimming •Heights •Work •Triggers: Alcohol, Sleep
Conditions on driving (Allowed after 6-12 months of seizure free)
Discuss the basics of treating epilepsy
Do not treat unless prolonged & recurrent.
Acute seizures •Almost always self limiting •Only need to treat acutely if; –Prolonged –Recurrent •Seizure termination –Benzodiazepines •Acute prophylaxis –Benzodiazepines –Phenytoin (Levetiracetam, Valproate)
What (2) medications are seizure-prophylactics?
Benzodiazepines
Phenytoin (Levetiracetam, Valproate)
What (1) medication can help terminate an acute seizure?
Benzodiazepines
Discuss SUDEP (Sudden Unexpected Death in Epilepsy)
- rate in epilepsy
- likely due to..
- related factor
•High rate of sudden death in epilepsy
–1-2 per 1000 patient years. 20-fold increase in 18-35yo
–Likely cardio-respiratory arrest: Often in sleep
•Related to seizure frequency
–Risk much reduced by seizure freedom
–6-9 per 1000 patient years in refractory focal epilepsy
