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
Classification
Partial (focal)
Generalized
• Simple
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•
•
•
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– Motor
– Sensitive
– Vegetative
– Psichical
• Complex
• Secondary generalized
Tonic
Atonic
Clonic
Tonic-clonic
Mioclonic
Absence
unclassifiable
International Classification of Seizures (ILAE, Epilepsia 1981)
Epilepsy
Primary Generalized Epilepsy
Focal or Partial
Seizure Features
Auras
Not present
Present
Occasionally present
Occasionally present
Present
Present
Starting with automatisms
Not usually present
Present
Prolonged postical confusion
without generalization
Not usually present
Present
Present
Present
Not present
Present
Not usually present
Present
Prodrome
Starting with LOC
Generalized tonic-clonic seizure
True versive head movements
Focal motor clonic or
tonic seizures
Risk Factors for Epilepsy
Family history of seizures
History of CNS infections, head
truama, febrile seizures, CNS
tumors, vascular malformation
May be present
Not usually present
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
Copyright 2002 The Cleveland Clinic Foundation
Generalized epileptiform
activity
Return to Epilepsy Article
Present
Not present
• Epileptogenesis
• The abnormal
discharge originates
usually in a definite
area
Investigatii
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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 Evolution
Normal
Pre-Seizure
Seizure
Post-Seizure
EEG - normal
-
Complexe virf-unda
fMRI
PET
Magnetoencefalography
TYPES OF SEIZURES
Generalized Seizures
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•
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•
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
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Motor (Jacksonian) seizures
Oculo-cefalogiric seizures
Adversive seizures
Supplementary motor area seizures
Tonic seizures
Sensory partial seizures
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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 range
Large range of efficacy
Narrow range
• Sodium valproate
• Phenytoin
• Levetiracetam
• Carbamazepine
• Phenobarbital
• Ethosuximide
• Benzodiazepines
• Gabapentin
• Topiramate
• Oxcarbazepine
• Lamotrigine
• Tiagabine
• Zonisamide*
• Pregabalin
* Based on preliminary evidence
Modern Antiepileptics
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Topiramate
Vigabatrin
Oxcarbazepine
Lamotrigine
Clobazam
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Gabapentin
Pregabalin
Tiagabine
Levetiracetam
Zonisamide
Adverse efects
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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
“People with epilepsy have
excelled in every area.”
Napoleon
Bonaparte
G. Julius
Caesar
Gustave Flaubert
Sokrates
Hermann von
Helmholtz
Vincent van Gogh
Alfred Nobel
Margaux
Hemingway
Lord Byron
Jeanne d'Arc
Wladimir Iljitsch
Lenin
F.M. Dostojewskij
Kardinal Richelieu