Epilepsy Flashcards
Epilepsy - Definition
Requires 2 or more unprovoked seizures separated by > 24 seizures OR 1 seizure with studies suggesting further risk for seizures
Seizures - Epidemiology
10% of population will have a seizure at some point in their lifespan
Only 1-2% of the population has epilepsy
36% of epilepsy is pharmacoresistant
Seizure - DDx
15-35% of patients thought to have seizure are found to actually have a different cause of episodic phenomena, including:
Syncope Movement Disorders Stroke/TIA Migraine Sleep Disorder Psychogenic/Behavioral
Seizure Classification
Partial (Focal) vs. Generalized Seizures
Partial Seizures - EEG characteristics
EEG discharges show increased activity in only one region of the brain
Subclassification of Generalized Seizures
Absence Myoclonic - Quick Jerks Tonic Clonic - Briet stiffening followed by quick jerks Tonic - Brief stiffening Atonic - Loss of tone and collapse
Complex partial seizure vs. Primary generalized absence seizure - Presentation
Both consist of a period of altered mental status accompanied by major motor manifestatios
Partial complex seizures - automatisms (chewing, hand wringing, etc.) are more common; usually followed by a post-ictal state
Absence seizures are usually not followed by a postictal state
Classification of epilepsy
Structural-metabolic - 30% of epilepsies, 1/2 will remit
Genetic predisposition - formerly ‘idiopathic’
Unknown - formerly ‘cryptogenic,’ thought to have an etiology that is not known yet
Febrile seizures
Usually occurs in children < 6 years old with onset of fever; usually occurs intermittently and resolves without treatment as the child ages
Subclassification of partial seizures
Characterized according to one or more features:
Aura
Motor
Autonomic
Dyscognitive vs. unaltered awareness/responsiveness
Benign vs. Catastrophic Epilepsy
Benign - easily treated with medications with normal intelligence, normal tests; remission may occur after teenage years
Catastrophic - intractable to medications, affects development with intellectual disability and shortened lifespan of child; EEG and MRI are abnormal; often will have symptomatic etiology of seizure
Bilateral consulsive seizure
Focal seizure that spreads to tonic-clonic
Approach to pharmacological treatment of epilepsy
In general, treatment is indicated after 2 seizures of unknown cause
Aim for monotherapy but polytherapy is indicated once a patient has failed 2 meds
Keep someone on meds for 2 years seizure free before consider weaning; consider EEG prior to weaning to give prognosis about seizure recurrence
Ketogenic diet
Carbohydrate starvation leads to production of ketone bodies, which have anti-epilepsy effect; 4:1 fat to carbohydrate ratio can be achieved with use of cream or MCT oil
Useful with all seizure types - 50% see a reduction of > 50% seizure frequency after 1 year; 7% achieve seizure free status
Chronic adverse effects of ketogenic diet
Hyperlipidemia Hyperuricemia Hypocalcemia Vitamin deficiency Acidosis Suboptimal growth
Serious / Life threatening
Kidney Stones (5-8%) Prolonged QT interval Increased bruising with bleeding Pancreatitis Immunosuppression
Vagal nerve stimulation
Implanted in the left chest wall; provides baseline stimulation of vagus nerve with gradual onset of anti-seizure effect
Useful in cases of chronic, intractable seizures to achieve 50% seizure reduction in 50% of patients
