Lecture 9: Epilepsy Classification and Etiology Flashcards
What is the ILAE?
International League Against Epilepsy
What is seizure semiology?
Clinical features of a seizure, what a seizure looks like
An epileptic seizure that beings with rhythmic shaking of the right hand most likely begins in the left pre-central gyrus because of which of the following?
Descending corticospinal tracts cross in the medulla
A newborn infant has a seizure that remains exquisitely localized to the right temporal cortex. The seizure discharge does NOT propagate to the right frontal cortex or other cortical regions. The clinical signs most likely to be seen are:
no obvious clinical signs
What is a seizure?
Transient dysfunction of all or part of the brain due to excessive discharge of a group of neurons, causing SUDDEN and TRANSIENT symptoms of a motor, sensory, autonomic or psychic nature
What is a provoked seizure? Significance?
A seizure with an immediate precipitant such as fever, head trauma, CNS infection
Provoked seizures are NOT epilepsy
What is an unprovoked seizure? Significance?
A seizure WITHOUT an immediate precipitant
Recurrent unprovoked seizures = epilepsy
What needs to happen in order to be defined as epilepsy?
Two or more unprovoked seizures = epilepsy
1 unprovoked seizures = a single unprovoked seizure
What is the epidemiology of epilepsy?
Greatest incidence in children and elderly
1% of elderly have epilepsy
.5% of teenagers have epilepsy
Cumulative incidence = 2.5-3%
Knowing seizure epidemiology, if you see a 45 y.o. HEALTHY female with no PMH presents with unprovoked seizures, what should your first thought be?
It might be a TUMOR
So if you have unprovoked seizures in unlikely age groups (20-60), think tumors
What are effective treatments for epilepsy?
- Fasting
-MOA is unknown but could be because of ketogenic release - Bromides
-interact with GABA to facilitate inhibitory neurotransmission - Phenobarbital
Acts via GABA-A receptors to facilitate inhibitory neurotransmission
-best shit for seizures
What is EEG?
-A measure of extra-cellular current from summed activity of many neurons
-Mainly reflects summed excitatory and inhibitory synaptic input to pyramidal cells
ODD number = left side of brain
EVEN number = right of brain
What is phenobarbital?
A barbiturate
Targets GABA-A and prolongs/potentiates action of GABA
What is EEG?
-A measure of extra-cellular current from summed activity of many neurons
-Mainly reflects summed excitatory and inhibitory synaptic input to pyramidal cells
ODD number = left side of brain
EVEN number = right of brain
What are the four categories in ILAE classification?
- Mode of epileptic seizure onset
- generalized vs. focal vs. unclear
- Epilepsy syndromes
- complex of signs and symptoms that define a recognizable type of epilepsy
- organized by AGE OF ONSET
- most epilepsies cant be classified in syndrome…but is useful if it can
- Epilepsy etiology
- genetic
- structural/metabolic
- unknown
- Evolution over time
- self limited or not (some can be outgrown, some need lifetime treatment)
- Treatment responsive or not
What are the three modes of seizure onset?
- Generalized
- Focal
- Unknown, unclear
What is post-ictal?
After seizure
What are the 6 types of generalized seizures?
Absence Myoclonic Tonic-clonic (primary) Tonic Clonic Atonic
What is a generalized seizure?
Starts deep down in center of brain (mayhaps thalamus or basal ganglia) and quickly spread to both sides
What is an absence seizure?
Generalized seizure
Sudden arrest of activity, stare, eye flutter, unresponsiveness,
-immediate return to baseline (no post-ictal state)
What is a myoclonic seizure?
Generalized seizure
Quick muscle jerks, usually symmetric, involving shoulders and arms
What is a tonic-clonic seizure?
Generalized seizure
AKA grand mal seizure, generalized convulsion
Begins with bilateral extremity extension and muscle stiffening and progresses to rhythmic shaking
-will begin with a LOUD sound from vocal cords
What is a tonic seizure?
Generalized seizure
Stiffening
Tonic phase without the clonic phase
What is a clonic seizure?
Generalized seizure
Rhythmic Shaking
Clonic phase without tonic phase
What is an atonic seizure?
Generalized seizure
Associated with FALLING DOWN
What is an epileptic spasm?
A generalized seizure
- neck and trunk flexion and arm and leg extension (immediate)
- seen in “West Syndrome” and “Infantile spasm”
How do you figure out if it is a generalized seizure vs. a focal onset with secondary generalization?
You have to use EEG and labs!
Also generalized seizure = involves both sides of body doing the same thing but
BEWARE
Many seizures that look generalized are really focal onset with rapid 2nd generalization
What are three types of focal seizures?
- Without impairment of awareness
- With impairment of awareness
- Evolving to a bilateral convulsive seizure
What is a focal seizure?
Start in a spot of the brain and may or may not spread to the rest of the brain
What is the clinical presentation of focal seizure in motor strip?
Clonic shaking of CONTRALATERAL limbs
What is the clinical presentation of focal seizure premotor cortex/SMA?
Complex, bilateral hypermotor activity
NOT RHYTHMIC!! … WILD
What is the clinical presentation of focal seizure in Broca’s area?
Expressive language dysfunction
What is the clinical presentation of fronto-polar (very front of front lobe)?
Arrest of activity, hypomotor
What is the clinical presentation of temporal lobe onset? Significance?
Aura, arrest of activity, unresponsiveness, motor automatisms
Looks exactly like Absence Generalized onset but this is where you have to keep DDx in mind and need to use EEG
Does pointless shit with his or her hands/legs (think of guy playing with bag)
What are motor automatisms?
Random movements
-fiddling movements
What is the clinical presentation of a focal parietal lobe onset?
Sensory signs or signs based on propagation to other lobes
Hard to tell
What is the clinical presentation of a focal occipital lobe onset
Visual signs (positive or negative)
What are the different types of epilepsy etiology?
- Genetic
- Structural/metabolic
- acquired (stroke, trauma)
- development (malformations of cortical development)
- Unknown
What are causes of epilepsy?
Hypoxia, hypoglycemia, hypocalcemia (0-6 months)
Head injuries
Cerebral tumours
Cerebrovascular degenerations
What is important to know about treating epilepsy?
If adults do not get seizure free after the second drug, they are known as treatment resistant and become a candidate for surgery
-there are certain medicines for generalized seizures vs. focal seizures
What are the consequences of childhood absence epilepsy (CAE)?
Greater risk of not being a high school graduate, special clsses, unplanned pregnancy
Psychosocially this is a BAD disease
What is childhood absence epilepsy?
A common type of generalized epilepsy with presumed genetic etiology
When child does the stop, stare and eye flutter
