Epilepsy and Seizures Definition of seizures and epilepsy Epidemiology Classification of seizures Examples Diferential diagnosis
Dec 22, 2015
Epilepsy and Seizures Definition of seizures and epilepsyEpidemiologyClassification of seizuresExamplesDiferential diagnosis
Clinical Definition of Seizure Paroxysmal uncontrolled discharges of neurons
within the central nervous system (grey matter disease).
“These Paroxysmal episodes of brain dysfunction manifested by stereotyped alteration in behavior” Clinical manifestations of a seizure based on anatomy
of the brain that is seizing Symptoms: sensory, motor, autonomic with or without loss of
consciousness
Epilepsy is a disease in which recurrent and unprovoked seizures occur spontaneously
What are seizures?
• Cellular definition: excessive or oversynchronized discharges of cortical neurons
• GABA receptor mediates inhibition responsible for normal termination of a seizure
• NMDA (Glutamate) receptor activation required for propagation of seizure activity
SeizureNMDA RcptrActivation
Reduced GABARcptr function
0
20
40
60
80
100
120
140
160
Yaş
4 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80
Fokal Epilepsi J eneralize Epilepsi
EEG interpretation !!
Seizure Classification
Seizure terms
Ictal= during seizure Post-ictal= confusion following
seizure Aura= abnormal sensation Automatisms= nonsensical
involuntary movements Tonic= tonic contraction producing
extension and arching Clonic= alternating muscle
contraction-relaxation
Partial= focal region involved Generalized= whole brain Convulsions= shaking
Seizure Phenotypesthink of anatomy!!
Cortex
Frontal EyeField
Brocas’s Speech Area
Primary Auditory Cortex
Sylvian Fissure
Wernicke’s Speech
Primary VisualCortex
Visual Assoc.Cortex
Central Sulcus
Partial SeizuresHomunculus
Frontal LobeFrontal Eye Field (Brodman’s 8)
Lesion: deviation of eyes to ipsilateral side Sz: overstimulation->eyes to contralateral side
Prefrontal Cortex (Brodman’s 9-12,46,47) Lesion: deficits in concentration, judgment and behavior Sz: agitation, odd behavior
Broca’s Speech Area (Brodman’s 44,45) Lesion/Sz: expressive nonfluent aphasias
Primary Motor Cortex (Brodman’s 4) Lesion: contralateral spastic paresis Sz: contralateral posturing/convulsions
Temporal LobeHippocampal Cortex
Bilateral lesions: inability to process short term to long term memory Sz: chronic seizures lead to deficits in short term memory
Wernicke’s Speech area (Brodman’s 22) Lesion/Sz: loss of receptive speech, fluent aphasia
Anterior Temporal Lobe Bilateral lesions: “Kluver-Bucy syndrome” of visual agnosia, oral
tendencies, hyperphagia, hypersexuality, docility Sz: pts “freeze” and might have oral automatisms
Primary Auditory (Brodman’s 41, 42) Bilateral lesion: cortical deafness Sz: auditory hallucinations
Olfactory Bulb (Brodman’s 34) Lesion: ipsilateral anosmia Sz: olfactory and gustatory hallucinations
Limbic SystemMeans “border” in Latin
Border between cortex and hypothalamus
Involved with emotional behavior Fear/anger/sexual behavior Short term memory
Includes: Hippocampus Fornix Mammilary bodies Ant. Nucleus thalamus Cingulate cortex
Seizures involving the hippocampus can have clinical symptoms of poor short term memory and abnormal mood
Parietal and Occipital LobePrimary Sensory Cortex (Brodman’s 3,1,2) Lesion: contralateral hemihypestheisa and
astereognosis Sz: contralateral sensory symptoms ie:
tingling, heatOccipital lobe (Brodman’s 17)
Lesion: contralateral hemianopsia with macular sparing
Sz: flashing or colored lights in contralateral visual field
Psychogenic non-epileptic seizures -PNES
Non-epileptic seizures May be manifestation of conversion disorder,
factitious disorder or malingering Features that may distinguish from epileptic
seizures Pre-attack preparation, absence of post-ictal confusion “Disorganized” movements, pelvic thrusting, thrashing Bilateral convulsions without loss of consciousness Violent or goal-directed behavior, obscene language, Forcefull eye closure Tongue biting Time!!!!!
Video EEG may help to diagnose