epilepsy I-II Flashcards
What is a seizure
an occasional, sudden, excessive and rapid discharge of gray matter, resulting in positive symptoms (ie. if the primary visual cortex is involved, the patent may be expected to experience visual hallucinations) and followed by negative symptoms (loss of function in brain area involved)
Mechanisms of post-ictal period
This is the period where negative symptoms occur following seizure. Due to neuronal exhaustion and inhibitory inputs to the area
Seizure classifications
generalized vs partial (focal)
Where do partial seizures occur
in one area of the cortex. May remain localized or spread to whole cortex causing grand mal seizure.
Where do general seizures occur
do not originate from a single abnormal focus, but instead these are thought to occur because the cortex as a whole is hyper-irritable. The cortex over reacts to inputs from deep gray matter
What are absence seizures,
A type of general seizure which involves widespread areas of cortex but not all layers of neurons. Varying cognitive impairment and are more common in children but can occur in adults
Compare absence seizures and partial complex seizures
. Both of these consist of a period of altered mental status unaccompanied by major motor manifestations. Simple behavior such as chewing and picking at clothing (automatisms) are more common in partial complex seizures, but may also be seen in absences. In general, partial complex seizures are followed by a postictal state whereas most absence seizures are not.
Most common cause of epilepsy
unknown-50%
Define epilepsy
–2 or more unprovoked seizures separated by greater than 24 hours or 1 seizure with studies suggesting further risk for seizures
classifications of partial seizures
simple or complex
classifications of generalized seizures
absence, myoclonic, tonic clonic, tonic, atonic
Understand that epilepsy is a disorder of recurrent, spontaneous seizures and that epilepsy can be classified by generalized and partial syndromes or by etiologies.
ok
List symptomatic seizures with known etiologies
Structural abnormalities: tumor or AVM
Who do most idiopathic seizures affect
children
Benign vs catastrophic epilepsy
Benign: easily treated with meds, normal Intelligence, genetic predisposition, tests are normal, unknown cause. Catastrophic: intractable to medications, affect development with mental retardation and shortens lifespan of child, EEG, MRI and other tests abnormal, symptomatic reason for seizure
Changes to focal seizures classifications
no longer complex and simple partial. Now classified by how they look (ie dyscognitive, focal motor, etc). If they spread to tonic clonic they are called bilateral convulsive.
When are seizures treated
if >2 or if acute reason for seizures such as tumor, stroke, etc
When is someone weaned off seizure meds
Must be seizure free for 2 years on meds
Meds for diff types of seizures
Generalized vs. partial: broad spectrum vs. partial. Syndromes (some medications worsen some seizures)- Lamotrigine for myoclonic, Phenytoin, carbamazepine, oxcarbazepine, gabapentin for generalized
Contraindications of valproic acid for seizures
•no valproic acid for teenage girls due to polycystic ovary disease and potential fetal issues. None for children <2 years.
What are intractable epilepsies
seizures which do not respond to a trial of at least 3 anticonvulsants and approximately 30% of new onset seizure patients may develop intractable epilepsy.
Non medication treatments used for seizures
ketogenic diet, vagal nerve stimulation and epilepsy surgery
Understand the definition and risk for recurrence of febrile seizures
Seizures that occur in infants or young children brought on by fever. Risk for recurrence if child is very young when first occurs, frequent fevers
Causes of status epilepticus
cerebrovascular disorders, brain trauma, infections, and low antiepileptic drug levels in patients with epilepsy. Less common causes present a clinical and diagnostic challenge, but are major determinants of prognosis. Among them, inflammatory causes and inborn errors of metabolism
