Epilepsy Flashcards
Epilepsy is
Basically the neurons start firing at a significantly greater rate then they are supposed to
A sudden derangement of the nervous system due to a sudden, excessive, disorderly discharge of cerebral neurons
Terminology:
Seizures vs Epilepsy
Seizures = single event Epilepsy = recurrent seizures
Causes of epilepsy
Idiopathic
Secondary – known cause (CVA, MS, infection)
Seizure Manifestations
-Loss of Consciousness
-Convulsive movements
(limbs, trunk, face)
-Impaired psychic function
(Sense that they are no
longer part of their own
body, or everything
seems to fade to
background)
-Disturbance of sensation
Numbness (esp. if 1o
sensory cortex),
-Visual hallucinations
Pathogenesis of epilepsy
If more excitatory than inhibitory neurotransmitters are released, the neuron will fire
Everyone has a certain about of excitatory and inhibitory NTs in the brain. So if there is an excessive amount of excitatory NTs to inhibitory NT it can potentially lead to a seizure. Medications try to balance these out either by inc. inhibitory or dec. excitatory
What is a convulsive seizure
If the disturbance flashes across the whole brain at once, it could produce a convulsive seizure, temporarily disrupting many of the functions of the brain.
What is the Seizure Threshold
If you have a low threshold for seizures that means that there is good chance of having a seizure -this means that there is a lot of excitatory activity in brain
A lot of excitatory activity in the brain is caused from either having a lot of excitatory NT or very little inhibitory NTs
The relative proportions of each determine whether a person has a low threshold for seizures (because of the higher excitatory balance) or a high threshold (because of greater inhibition).
A low seizure threshold ↑ the risk of epilepsy
What factors determine the character of the seizure, impact on person and social consequences involved
1) The location of that event
2) The extent of its reach within the tissue of the brain
3) The duration of the event (how long it lasts)
4 Types of Seizures
a) Generalized seizures
-Bilateral & symmetrical
w/o
focal onset
-May be idiopathic
b) Focal (Partial) seizures
-Never idiopathic
c) Status epilepticus
d) Non-epileptic seizures
Types of Generalized Seizures (4)
Grand Mal Seizures (Tonic-Clonic Seizures-tone to clonic)
Petit Mal Seizures (Absence Seizures)
Myoclonic Seizures
Atonic Seizures
Generalized Tonic-Clonic (grand mal) Duration
1 to 2 min
Generalized Tonic-Clonic (grand mal) Seizure Sx
A cry Fall Tonicity (rigidity) Clonicity (jerking) May have cyanosis
Generalized Tonic-Clonic (grand mal) Postictal Sx
Amnesia for seizure events
Confusion
Deep sleep
Absence (petit mal) Duration
2 to 15 sec
Absence (petit mal) Seizure Sx
Stare
Eyes fluttering
Automatisms if prolonged
Absence (petit mal) Postictal Sx
Amnesia for seizure events
No confusion
Promptly resumes activity
What is the most common & best known type of generalized seizure
Grand-mal seizures (Tonic-Clonic)
Prodrome means
Occurs several hours before the event
Apathy, depression, euphoria, myoclonic jerks
An aura is
An ‘aura’ is the term that some people use to describe the warning they feel before they have a tonic clonic seizure.
occurs a few seconds before LOC
Turning of head, palpitations, unnatural sensations (i.e. butterflies in stomach)
(it is a warning sign before a tonic clonic seizure)
Grand mal seizure tonic phase, how long does it last and what happens to the person
Seizure – sudden LOC and fall
Tonic Phase (lots of tone) – 10-20 seconds:
Legs extend, arms in “hands up” position
Jaw snaps shut (tongue gets bitten), emits loud cry
Breathing ceases causing cyanosis
Bladder empties
Pupil fixed and dilated
Babinski signs
Grand mal seizure, clonic phase, how long does it last and what happens to the person
Clonic Phase (30-60 seconds)-body starts to relax from fully tonic contraction
Generalized coarse tremor (repetitive relaxation of tonic contraction)
Facial grimacing & frothing of the mouth
Continues to be apneic
Often salivates
Grand mal seizure, post-clonic phase, how long does it last and what happens to the person
Post-clonic phase – pt lies limp in a deep sleep (body relaxes and slowly returns to normal)
Pupillary reactivity returns
Breathing normalizes
After 5 min, awakens but appears drowsy/confused
May fall asleep for several hours more afterwards
3 phases of a grand mal seizure
Tonic phase
Clonic phase
Post Clonic phase
Petit Mal Seizures are
Lapses of awareness, sometimes w/ staring, that begin & end abruptly, lasting only 2-15 sec
There is no warning & no after-effect
More common in children than in adults
Usually begins age 4-12
Always idiopathic
Little, if any, motor activity – may see rhythmic movements of facial muscles (i.e. lipsmacking)
Can be induced by hyperventilation
Why do petit mal seizures happen and are there warning signs
no warning and no after affect - What we normally see is blank stares ore absents in awareness
We don’t know why it happens, but it usually happens when we are younger
no motor activity when it happens
Myoclonic seizures are
Rapid, brief contractions of bodily muscles, which usually occur at the same time on both sides of the body
contraction of the muscles - tonic seizures
Atonic seizures are
Abrupt loss of muscle tone Aka drop attacks Causes head drops, loss of posture, or sudden collapse ➡ head injuries Protective headgear is sometimes used Tend to be resistant to drug therapy
Which seizure is known for drop attacks
Atonic seizures- all the muscles stop working/loss of muscle tone, lead to “drop attacks” just fall to the ground (this is very dangerous, injuries to neck and face common)
What are partial seizures and what is the part of the brain it often affects
Most commonly seen in temporal lobe
Partial seizures may spread to cause a generalized seizure, in which case the classification category is partial seizures secondarily generalized.
Virtually any movement, sensory, or emotional symptoms can occur as part of a partial seizure, including complex visual or auditory hallucinations.
2 common subdivisions of partial seizures
Simple partial seizures – (-) LOC
Complex partial seizures – (+) LOC
Simple partial duration
90 sec
Simple partial Seizure Sx
No LOC
Sudden jerking
Sensory phenomena
Simple partial Postictal Sx
Possible transient weakness or loss of sensation
Complex partial Duration
1 to 2 min
Complex partial Seizure Sx
May have aura
Automatisms
Unaware of environment
May wander
Complex partial Postictal Sx
Amnesia for seizure events
Mild to moderate confusion
Sleepy
Complex partial seizure auras
Complex hallucinations of all senses
Perceptual illusions
Dyscognitive state: ↑ reality or familiarity (deja vu); unfamiliarity (jamais vu), depersonalization (i.e. undressing in public)
Affective experiences: fear, anxiety, rage
Automatism ex, and happens with
Automatism example: hand tapping that keeps going, lip smacking
Happens with complex partial seizures
Complex partial seizures and simple partial seizures
They do have LOC and can keep doing complex activities
When you have a complex partial seizure they are a bit more involved. You start getting more hallucinations and decreased period of responsiveness and after the complex some sort of altered behavior
Status Epilepticus is
Literally a “continuous state of seizure”
Seizures are prolonged, or occur in a series, lasting > 30 minutes
What is one of the first things you should do if a person is having a seizure
Make sure person is safe and check the time
When should you call the hospital for a seizure
if it lasts more than 5 mins and the person is pregnant
Status Epilepticus likely causes
Do not know what causes it but some likely causes
Brain tumors or infections Craniocerebral trauma Cerebrovascular disease Ingestion of cocaine or other illegal drugs Toxic or metabolic disorders
Status epilepticus and history of seizures
Most people that this happens to have no history of seizures
and do not have a h/o epilipsy
Nonepileptic Seizures aka and what is this
Pseudoseizures
They have very similar symptoms as a seizure but they do not have the excessive electrical activity in the cortex of the brain.
Nonepileptic Seizures vs epileptic seizures
Episodes that briefly change a person’s behavior & often look like epileptic seizures.
Epileptic seizures are caused by abnormal electrical changes in the cortex, whereas nonepileptic seizures are not caused by electrical disruptions in the brain.
Seizure triggers are and can include
Typically unpredictable, triggers can include:
Missed medication
Sleep/wake cycle fluctuations
Hormonal fluctuations
Pregnancy & menstrual cycles
Excessive use and/or withdrawal from alcohol or drugs
Fever; physical stress
Mental/emotional stress (worry, anxiety, anger)
Hyperventilation
What is “reflex epilepsy” and name some triggers
When cause by one specific stimulus
A condition in which seizures can be provoked by an external stimulus (flashing lights) or, occasionally, by an internal mental process (mathematical calculation).
Fairly predictable in response to specific stimuli, and may coexist with spontaneously occurring seizures
Triggers: flashing lights, high contrast color/shape/stripe patterns, complex mental processes (calculations)
Diagnosis of epilepsy
-Patient history
-Neurological exam
-Supporting blood work - to rule out
-Electroencephalograph (EEG)
(Records signals produced by electrical discharge of neurons)
-MRI/CT of the brain - to rule out
-PET scans if available
-Must r/o other causes: TIA, hypoglycemia, fainting
Management of Epilepsy and can it be cured
There is no cure for epilepsy currently:
- Medications
- Surgery
- Vagus Nerve Stimulation
- Ketogenic Diet
When is surgery and option for epilepsy
For intractable surgery not responding to meds
What type of surgery is done for epilepsy
-Surgical removal of seizure-producing areas
-Partial/complete lobectomy or cortical resection
(Anterior temporal lobectomy most common)
- Hemispherectomy
- Corpus Callosotomy (so it doesn’t travel to the other side of the hemisphere)
- Multiple Sub-pial Transection (cutting the connections so seizure can not travel
Who would benefit from vagus nerve stimulation
For people who know their trigger, if they stimulate the vagus nerve they can limit the oncoming of the seizure
