seizures Flashcards
Epilepsy is a chronic condition that can be diagnosed after a patient has _____ unprovoked seizures more than 24 hours apart.
two
Epilepsy states that epilepsy is best charcterized as a group of syndromes that are concerned with ________, _____, & ______ consequences of the conditions that promote seizure recurrence.
neurobiological, cognitive, and psychological
Status epilepticus refers to a neurological emergency in which a single seizure last for more than ____ minutes or repeated seizures are present without a recovery of consciousness in between.
5 minutes
seizure resistant to pharmacotherapy and death have been associated with ______ seizure duration.
increased.
Epilepsy is the ______ most common neurological disorder in the United States.
third
The incidence is highest in what two age groups?
individuals over 65 years of age and those under two years of age.
Epilepsy is observed to be more prevalent in what ethnicity? and what other group of people?
african Americans and the socially disadvantaged populations.
it is estimated what percentage of the american population will experience a seziure in their lifetime?
10%
Epilepsy has a strong association with what psychological disorder?
depression
Epilepsy is noted to generate an imbalance between _____ and _____ neuro transmitters, resulting in seizures
Inhibitory GABA signaling
Excitatory glutamatergic signaling
People with epilepsy have a mortality rate that is ____ to _____ times higher than that of the general population.
2 to 3
Individuals with epilepsy have risk of sudden death that is ____ times greater than the general population
25
Epiliepsy is found in 13-25% of what four disorders?
autism
cerebral palsy
Down Syndrome
Intellectual Disability
Several types of seizures begin within or spread to the _______ ______.
cerebral cortex
Too much _____ can cause a seizure and too little ___ can cause a seizure
too much Glutamate (Eccess–matE)
too little GABA (insufficient)
describe what the cerebral cortex is?
the outer layer of the neuronal tissue that surrounds the hemisphere of the human brain.
name the two major classes of seizures?
focal and generalized
what type of seizures typically start in one hemisphere of the brain
focal
What are the 2 types of symptom classes that focal seizures can produce
motor or non-motor symptoms
Focal seizures are unilateral or bilateral? meaning what?
unilateral
meaning they do not spread beyond the local network of neurons in a single hemisphere of the brain.
what are the 3 types of awareness that take place during focal seizures
- still aware (awake/concious)
- unaware
- awareness unknown
Generalized seizures are unilateral or bilateral? Meaning what?
Bilateral and symmetrical
meaning they cause electrophysical disturbances across the entire brain.
the cerebral cortex can be subdivided into regions called?
lobes
name the lobes of the cerebral cortex.
frontal
parietal
temporal
occipital
even though focal seizures occur in ___ hemisphere, these seizures can also transition into _____ seizures
- one hemisphere
- bilateral tonic clonic seizures
What are the motor symptoms associated with focal seizures
- Tonic: constant stiffness
- Atonic: limp or loss of muscle tone
- myoclonic: brief jerking movements
- clonic: rhythmic jerking
- hyper-motor: thrashing, kicking, clapping
- Epileptic spasms: sudden flexion, extension, grimacing head noding
what can dictate the symptoms or clinical presentation of the seizure?
the regions of the brain that are affected by the abnormal electrophysiological activity.
what are the non motor symptoms associated with focal seizures
- Sensory (olfactory, visual, auditory_
- Cognitive (issues thinking, focusing, memory problems)
- Emotional (laughing, crying, fear)
- Autonomic: (cardiovascular or gastrointestinal)
Abnormal network activity that spreads to the frontal lobe is most commonly associated with seizure types that result in?
loss of consciousness
seizures that in motor dyfunction (AKA jerking) movements or muscle rigidity typically involve the portions of the?
lower brain and brainstem that are responsible for controlling movement.
describe atonic
limp or loss os muscle tone
describe myoclonic
brief jerking movements
describe clonic
rhythmic jerking
neuronal activity normally occurs in a _____ manner, resulting int he ordered transfer of information across synapses from one region of the brain to another
sequential
describe epileptic spasms
sudden flexion, extension, grimacing head nodding
how long do focal seizures last
1-2 minutes
if a focal seizure changes into a bilateral tonic clonic seizure, these seizures are also classified as
generalized seizures
what hemispheres do generalized seizures affect
both hemispheres (which can cause bilateral motor symptoms)
what are the two types of generalized seizures
motor or absence seizures
what physically surround the neuronal networks to regulate the duration and extent to which the wave of activity can spread
specialized neurons called interneurons and glial cells.
in comparison to focal seizures, generalized seizures always cause
impaired awareness
what type of motor symptoms can be produced as a result of generalized motor seizures
tonic, atonic, myoclonic, clonic, epileptic spasms, or combination of these
for generalized absence seizures can differentiated into ___ or _____
Typical or atypical
can inhibitory neurons be overcome?causing what?
yes
initiation of a seizure
In generalized absence seizures, what type of symptoms are present when classified as typical
suddent onset of a blank stare, upward deviation of the eyes, and an inability to respond
the early phase of ictogenesis is often referred to as ?
initation
ictogenesis results from what?
rapid succession of synchronized action potentials in a subset of neighboring neurons.
in generalized absence seizures, what type of symptoms are produced from the atypical category
when the seizures presents with a change in muscle tone and the onset and end of the seizure is not quick like typical absence seizures
the burst of excitatory activity that causes ictogenesis is caused by?
long lasting depolarization of neuronal membranes due to calcium influx and opening of voltage dependent sodium channels
Generalized absence seizures typically lasts _____ and have a ____ recovery
1-2 minutes
quick recovery
With generalized absence seizures, what are the two different types of motor movements that can be present
myoclonic (jerking movements) or eyelid Myoclonia
repetitive action potentials can lead to an accumulation of ______ in presynaptic terminals.
calcium
the accumulation of calcium in presynaptic terminals, leads to enhanced release of ______ and propagation of seizure activity to?
neurotransmitters
adjacent groups of neurons
What is eyelid myoclonia defined as
jerking movement of the eyelids with the eyes moving upward
the combination of membrane depolarization and the presence of excitatory neurotransmitters such as _____ stimulate the NMDA receptor which further enhances neuronal activation via the _____ influx
glutamate
calcium
since some patients have seizures that are unwitnessed by a third party, these types of seizures are classified as
unknown onset
what is epileptogensis?
the transformation of a normal neuronal network into one that is chronically hyper excitable
what are the two characteristics that need to be described by the patient or a witness to diagnose the type of seizure in addition to an EEG
- the types of motor symptoms witnessed
- how aware the patient was
local neurotransmitter imbalances may be a potential mechanism for ?
focal epileptogenesis
in suceptible patients temporary imbalances between ____ and _____, as well as the influence of neuromodulators such as ______ and ________ neurotransmitters might trigger the initation of a seizure
glutamate and GABA
acetylcholine and monamine neurotransmitters
what is Lennox Gastaut syndrome
childhood epileptic encephalopathy that is categorized by the clinical triad of multiple types of generalized seizures, mental retardation or regression and diffuse slope of spikes and and waves on an EEG
seizures resulting from brain injury usually exhibit a delay of ____ to ____ between an initial CNS injury and the first seizure
months to years
name a few examples of CNS injury that can lead to seizures
trauma
stroke
fever or infection
when does Lennox Gastaur syndrome (LGS) typically occur
in children within the first 7 years of life
LGS typically causes ____ seizures and often include ______
multiple daily seizures along with drop attacks
what are the three steps taken in order to classify a type of seizure
- determine if the seizure is focal, generalized, or unknown
- verify that the patient had impaired awareness during the seizure (lack of responsiveness, LOC, does not recall the events that occur during the seizure)
- determine if motor, non-motor, or absense symptoms were present
Many patients with different types of temporal lobe epilepsy (related to structural changes in neuronal networks) have highly selective loss of ? that do what?
inhibitory neurons
that may regulate the excitatory neurons within the dentate gyrus
what is the dentate gyrus
a group of neurons in the hippocampus
when verifying that the patient had impaired awareness during the seizure, if any of these markers are true (LOC..etc) then the patient is classified as having _______awareness. However, if no one can verify the level of the patients awareness, it is considered that the patient had _____ awareness
impaired awareness
unknown awareness
an initial injury such as a head injury, may lead to very focal confined region of structural change that causes local ________, which lead to further structural changes that evolve over time until the focal lesion produces clinically evident _____.
hyperexcitability
seizures
motor and non motor symptoms can initially present like a focal seizure and progress into _____
a bilateral tonic clonic seizure
Diagnosis of seizure disorder consists of?
physical examination
patient history
EEG recordings
An MRI or CT can be performed to rule out _____ for seizures
CNS disorders
____% of seizures have no known cause
50%
Physical examination can evaluate seizure disorders that can be associated with?
epilepsy
what are the three types of etiologies that seizures can be classified as
idiopathic, symptomatic, or unknown
Common etiologies related to epilepsy include (try to name a few, there is 8 altogether)?
TBI
infections
alcohol or drug abuse
stroke
brain tumor
Alzheimer’s disease
electrolyte distrubances
genetic factors
for idiopathic causes of a seizure, this is attributed to ______ etiology, but related to ______ cause
unknown underlying etiology
genetic or family history cause
for symptomatic etiology, this is classsified as _______ etiology, or _____ as an underlying cause
underlying cause or evidence of brain injury
cryptogenic is considered symptomatic but with no documented underlying cause
for an unknown or undetermines etiology, this refers to
no identifiable cause
Though there is no laboratory test for epilepsy, _____ levels may be transiently elevated for up to 20 minutes after a seizure has occurred.
serum prolactin
when is an EEG typically obtained after a patient has a seizure
48 hrs or more after a seizure episode
___% of patient with true seizures will have multiple ____ EEG’s
10% and normal EEG’s
_____ can also be performed to rule out an metabolic causes of a seizure
drug toxicity or alcohol screen
EEG can provide what information about seizures?
the type and location of the seizure focus
epilepsy can impact a person’s quality of life through associated pain, anxiety, and _____.
insomnia
