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Definition
• Epilepsy: A group of recurrent disorders of cerebral function characterized by both seizures and convulsions.– Convulsion: Sudden attack of involuntary muscular
contractions and relaxations.– Seizure: Abnormal central nervous system electrical
activity.
• Sezures are generated by abnormal synchronous electrical brain activity
Etiology
• Idiopathic – genetic conditions• Acquired:
– Trauma– Brain tumors– Stroke – Infections– Degenerative diseases
Ion channels
• Proteins that are organised into small pores in the
cell membrane
• They allow selective passage of ions (Na, Ca, K,
Cl), with an important contribution in maintaining the
membrane potential and in forming the trans
membranare electric flow.
• Intercelular signals, transmembrane transport, pH
and cell volume
Calcium channel
Natrium channel
Na channel
Potassium channel
ClassificationPartial (focal)• Simple
– Motor– Sensitive– Vegetative– Psichical
• Complex• Secondary generalized
Generalized• Tonic• Atonic• Clonic• Tonic-clonic• Mioclonic• Absence
unclassifiable
International Classification of Seizures (ILAE, Epilepsia 1981)
Copyright 2002 The Cleveland Clinic Foundation
Return to Epilepsy Article
Epilepsy Primary Generalized Epilepsy Focal or Partial
Seizure Features
Auras Not present Present
Prodrome Occasionally present Occasionally present
Starting with LOC Present Present
Starting with automatisms Not usually present Present
Prolonged postical confusion without generalization
Not usually present Present
Generalized tonic-clonic seizure Present Present
True versive head movements Not present Present
Focal motor clonic or tonic seizures
Not usually present Present
Risk Factors for Epilepsy
Family history of seizures May be present Not usually present
History of CNS infections, head truama, febrile seizures, CNS tumors, vascular malformation
Not usually present May be present
Examination Findings
Neurologic examination Usually normal May be abnormal
Neuroimaging Findings
Brain MRI Usually normal May be abnormal
EEG Findings
Generalized epileptiform activity Present Not present
Focal epileptiform activity Not present Present
• Epileptogenesis
• The abnormal discharge originates usually in a definite area
Investigatii• Electroencefalogrphy – spectral analysis• Cerebral Computed Tomography (CT)• MRI• Functional imagistics techniques:
– PET– fMRI– SPECT
• Magnetoencephalography• video – EEG monitoring
Scalp EEG Data Acquisition
10-second EEGs: Seizure EvolutionNormal Pre-Seizure
Seizure Post-Seizure
EEG - normal
-
Complexe virf-unda
fMRI
PET
Magneto-encefalography
TYPES OF SEIZURES
Generalized Seizures
• Grand Mal• Absence• Tonic seizures• Atonic seizures• Mioclonic seizures
Generalized Seizures
• Excessive electrical activity in both cerebral hemispheres.
• Usually originates in the thalamus or brainstem.
• Affects the whole body.
• Loss of consciousness is common.
Generalized Seizures • Myoclonic: Brief shock-like muscle jerks generalized or
restricted to part of one extremity.
• Atonic: Sudden loss of muscle tone.
• Tonic Seizures: sudden stiffening of the body, arms, or legs
• Clonic Seizures: rhythmic jerking movements of the arms and legs without a tonic component
• Tonic-clonic (grand mal): – Tonic phase followed by clonic phase
http://www.nlm.nih.gov/medlineplus/ency/images/ency/fullsize/19076.jpg
Generalized Seizures
• Absence (petit mal): Person appears to “blank out” - “Daydreaming”– Simple Absence (primarily effects consciousness only)– Complex Absence– Atypical Absence (Includes physical symptoms like eye blinking or
lip movements)
• Status Epilepticus: A seizure lasting longer than 30 min, or 3 seizures without a normal period in between– May be fatal
– Emergency intervention required
Grand Mal epilepsy
Absences
Partial (focal) Seizures
• Excessive electrical activity in one cerebral hemisphere. -Affects only part of the body.
• Simple Partial: Person may experience a range of strange or unusual sensations.– Motor– Sensory– Autonomic– Key feature: preservation of consciousness.
Partial (focal) Seizures
• Complex Partial:
– Loss of awareness at seizure onset. Person seems dazed or confused and exhibits meaningless behaviors.
– Typically originate in frontal or temporal lobes (e.g. Temporal lobe epilepsy)
Motor partial seizures• Motor (Jacksonian) seizures• Oculo-cefalogiric seizures• Adversive seizures• Supplementary motor area seizures • Tonic seizures
Sensory partial seizures
• Jacksonian sensory seizures• Visual • Auditive • Vestibulary • Olfactive & gustative• Vegetative
Partial complex seizures
Association areas are involved:• Partial loss of awareness• Dream state,• Déjà vu,• Jamais vu• Anger, fear, joy crisis
Partial motor & sensory seizures
Complex partial seizures
• Drugs
• Cetogenic diet
• Surgery
• Vagal stimulation
Treatment principles
• Monotherapy
• Politherapy
• Titration
• Treatment cessation
Absence seizures
• Etosuximide
• Oxazolidindione
Drugs that work in seizures other than absence
• Phenobarbital
• Phenitoin
• Carbamazepine
• Primidone
Drugs efficient in all types of seizures
• Sodium valproate
• Clonazepam
Status epilepticus
• Prolonged seizure or seizures without remission periods between
• Parenteral treatment:–Clonazepam–Diazepam–Phenitoin
Antiepileptics: efficacy rangeAntiepileptics: efficacy rangeLarge range
of efficacyNarrow range
* Based on preliminary evidence
• Sodium valproate• Levetiracetam• Phenobarbital• Benzodiazepines• Topiramate• Lamotrigine• Zonisamide*
• Phenytoin• Carbamazepine• Ethosuximide• Gabapentin• Oxcarbazepine• Tiagabine• Pregabalin
Modern Antiepileptics
• Topiramate• Vigabatrin• Oxcarbazepine• Lamotrigine• Clobazam
• Gabapentin• Pregabalin• Tiagabine• Levetiracetam• Zonisamide
Adverse efects
• Gingival hyperplasia• Hirsutism/ Transient hair loss • Vitamine/folate deficiency• Polycystic ovary syndrome and menstrual
disturbances • Bone loss
Surgery
• Resection of epileptic abnormal discharge source
• Lobectomiy
• Hemispherectomy
• Calosotomy
Vagal stimulation
• Electrodes are attached to the vagus nerve
• Intermittent stimulation
• Indication in treatment resistent epilepsy
Special issues
• Driving
• Extreme/risky sports
• Special professions
• Pregnancy and breast feeding
Lord Byron
“People with epilepsy have excelled in every area.”
Kardinal Richelieu
Wladimir Iljitsch Lenin
Margaux Hemingway
Vincent van Gogh
Gustave Flaubert
Jeanne d'Arc
Hermann von Helmholtz
Alfred Nobel
Sokrates
G. Julius Caesar
Napoleon Bonaparte
F.M. Dostojewskij