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