Epilepsy

Dr. Zuraini, sps

What Is the Difference Between Epilepsy & Seizures? A seizure is a brief, temporary disturbance in the electrical activity of the brainEpilepsy is a disorder characterized by recurring seizures (also known as seizure disorder)A seizure is a symptom of epilepsy*

Seizure: time-limited paroxysmal events that result from abnormal, involuntary, rhythmic neuronal discharges in the brainUnpredictable (can occur at inconvenient, embarrassing, or even dangerous times) Convulsion: the muscle contractions that can occur during a seizure.*

A seizure is as a sudden, disorderly discharge of cerebral neurons.

Seizures involve a transient alteration in brain function involving motor, sensory, autonomic, or psychic clinical manifestations

The occurrence of repeated unprovoked seizures*Unprovoked seizure: events occurring in absence of a recognized etiological or risk factor (idiopathic and cryptogenic) and events occurring in patients with antecedent stable (non-progressive) CNS insults (remote symptomatic seizure).A chronic disorder characterized by recurrent (more than 2) unprovoked seizures.

*ILAE, Epilepsia1993;34:592-6*

Aura: A partial seizure experience before the onset of a generalized seizure; often described as a funny feelingProdroma: Early clinical manifestations that may occur hours to a few days before the onset of a seizure (malaise, headache, or depression)Tonic phase: A state of muscle contraction with increased muscle tone (associated with loss of consciousness)

Clonic phase: Alternating contraction and relaxation of musclesPostictal phase: Time period immediately after the end of seizure activity

About 2.3 million Americans have epilepsy (0.5-1% of the population)Roughly 181,000 new cases of seizures and epilepsy occur each year50% of people with epilepsy develop seizures by the age of 25; however, anyone can get epilepsy at any timeNow there are as many people with epilepsy who are 60 or older as children aged 10 or younger

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All brain functions -- including feeling, seeing, thinking, and moving muscles -- depend on electrical signals passed between nerve cells in the brain

A seizure occurs when too many nerve cells in the brain fire too quickly causing an electrical storm

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In about 70% of people with epilepsy, the cause is not knownIn 30%, most common causes are:- Head traumaInfection of brain tissueBrain tumor and strokeHeredity- Prenatal disturbance of brain development

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Is this a seizure?Is this a provoked or unprovoked seizure?What is the probability of recurrence of seizures (to establish a diagnosis of epilepsy)?*

Primary epilepsySecondary epilepsyPrenatal and perinatal factorsTrauma and surgeryMetabolic cuasesToxic causes*

5. Infectious and inflammatory causes6. Cerebral vascular diesease7. Intracranial tumors8. Hypoxia9. Degenerative disease

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Electrical discharges between neurons are usually restricted, and produce the normal rhythm recorded on the EEG (electroencephalogram).When a seizure occurs, large groups of neurons are activated repetitively and hypersynchronously, with dysfunction of the inhibitory synaptic contact between neurons. This produces the high-voltage spike-and-wave activity on the EEG.

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The onset of the epileptic discharge may include the whole cortex (primary generalized), may be confined to one area of the cortex(partial), or may start focally and then spread to involve the whole cortex (secondary generalization of a partial seizure).*

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Psychogenic nonepileptic spell (pseudoseizure)SyncopeMigraineTransient Ischemic attackSleep behaviors and disordersMovement disorders*

CharacteristicsProlonged duration of event (10-30 min)Preservation of consciousness despite whole body jerkingBizarre and asynchronous motor movementsPelvic thrusting movementsNot stereotypical*

Metabolic abnormalitiesHypo/HyperglycemiaHyponatremiaHypocalcemiaAlcohol withdrawalAcute neurological insult Infection (meningitis, encephalitis)Stroke (ischemic, hemorrhagic)Head traumaIllicit drug intoxication the lowers seizure threshold (i.e. Theophylline, tricyclic antidepressant)High fever in children*

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Focal seizures account for 80% of adult epilepsiesSimple partial seizuresComplex partial seizuresPartial seizures secondarilly generalised

Generalised seizures

Unclassified seizures*

I. Partial (focal, local) seizures A. Simple partial seizures (consciousness not impaired)B. Complex partial seizures (with impairment of consciousness)C.partial seizures evolving to generalized seizures

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Simple partial seizures Motor, sensory, vegetative or psychic symptomatology Typically consciousness is preserved

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Complex partial seizures (= psychomotor seizures) Initial subjective feeling (aura), loss of consciousness, abnormal behavior (perioral and hand automatisms) Usually originates in TL*

Partial seizures evolving to tonic/clonic convulsions secondary generalised tonic/clonic seizures (sGTCS)*

II. Generalized seizuresA. Absence seizures1. Absence seizures2. Atypical absence seizuresB. Myoclonic seizuresC. Clonic seizuresD. Tonic seizuresE. Tonic-clonic seizuresF. Atonic seizures (astatic seizures)III. Unclassified seizures

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AbsencesMyoclonic seizuresClonic seizuresTonic seizuresAtonic seizures

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I. Localization-related (focal, local, partial) epilepsies and syndromesA. Idiopathic (with age-related onset). At present, two syndromes are established: 1. Benign childhood epilepsy with centro temporal spikes2.Childhood epilepsy with occipital paroxysmsB. Symptomatic. This category comprises syndromes of great individual variability.*

Temporal lobe epilepsyFrontal lobe epilepsyParietal lobe epilepsyOccipital lobe epilepsyAbsence epilepsyMyoclonic epilepsySyndrome*

Medial basalAura: epigastric discomfort, autonomic sign eg. Pallor, flushing, fearful, olfactory and gustatoryLateral temporalAuditory/visual disturbance/speechLasting > 1 min, amnesia, post-ictal confusion with gradual recovery to normal

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Brief durationComplex partial with little or no postictal confusionRapid secondary generalizationProminent tonic or postural movementFrequent complex gestural automatism at onsetFrequent falling when discharges are bilateral.*

Sensory at the onsetTactile, tingling, electricity, crawling, stiffness, cold, or pain, or unpleasant dysaesthesias. Post-ictal transient deficit eg. Cortical sensory deficit*

Eye movement, head turning and/or visual hallucinationsHallucination:Posteriorly: unstructured lightAnteriorly: structured image or visual distortions such as macropsia or micropsia*

Localization-Related EpilepsyEpilepsy syndromeGeneralized EpilepsyIdiopathicSymptomaticCryptogenicIdiopathicSymptomaticCryptogenic*

Idiopathic epilepsy*

Localization-relatedGeneralizedBFEC (Benign Rolandic Epilepsy of Childhood)Benign neonatal convulsionBenign Occipital Epilepsy of childhoodBenign myoclonic epilepsy in infancyAutosomal Dominant Nocturnal Frontal Lobe EpilepsyCAEPrimary reading epilepsyJAEJMEEpilepsy with generalized tonic-clonic seizures on awakeningSome reflex epilepsy

Symptomatic epilepsy*

Localization-relatedGeneralizedTemporal lobeEarly myoclonic encephalopathiesFrontal lobeEarly infantile epileptic with suppression burst (Ohtahar syndrome)Parietal lobeCortical abnormalities dysplasiasOccipital lobeMetabolic abnormalitiesRasmussen encephalitisWest syndromeMost reflex epilepsiesLennox-Gastaut syndrome

Cryptogenic epilepsy*

Localization-relatedGeneralizedAny occurrence of partial seizure without obvious pathologic causeEpilepsy with myoclonic-astatic seizuresEpilepsy with myoclonic absence seizures

II. Generalized epilepsies and syndromesA. Idiopathic (with age-related onset, in order of age appearance) 1. Benign neonatal familial convulsions 2. Benign neonatal convulsions 3. Benign myoclonic epilepsy in infancy 4. Childhood absence epilepsy (pyknolepsy, petit mal) 5. Juvenile absence epilepsy 6. Juvenile myoclonic epilepsy (impulsive petit mal) 7. Epilepsy with grand mal seizures on awakening *

II. Generalized epilepsies and syndromesB. Idiopathic, symptomatic, or both (in order of age of appearance) 1. Infantile Spasms 2. Lennox Gastaux 3. Epilepsy with myoclonic-astatic seizures4. Epilepsy with myoclonic absences

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C. Symptomatic 1. Nonspecific cause, early myoclonic encephalopathy 2. Specific syndromes. Epileptic seizures may complicate many disease states. Under this heading are included those diseases in which seizures are a presenting or predominant feature.*

III. Epilepsies and syndromes undetermined as to whether they are focal or generalized A. With both generalized and focal seizures 1.Neonatal seizures 2. Severe myoclonic epilepsy in infancy 3. Epilepsy with continuous spikes and waves during slow-wave sleep4. Acquired epileptic aphasia (Landau- Kleffner syndrome)B. Without unequivocal generalized or focal features*

IV. Special syndromes A. Situation-related seizures 1. Febrile convulsions 2.Seizures related to other identifiable situations, such as stress, hormones, drugs, alcohol, or sleep deprivation B. Isolated, apparently unprovoked epileptic events C. Epilepsies characterized by the specific modes of seizures precipitated D. Chronic progressive epilepsia partialis continua of childhood

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Stress, emotionSleep/sleep deprivationHyperventilationFeverMedications, metabolic disturbanceReflex epilepsyPhotic stimuli: TV, flashing lights, visual patternsStartle, music, reading, eating*

EEGMRI brain1st Unexplained seizure does not necessitate AED treatment except:Recognized epileptic syndrome with high probability of recurrence.Focal brain lesion.

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Absence EpilepsyJuvenile Myoclonic EpilepsyBenign Rolandic EpilepsyInfantile SpasmsLennox Gastaux*

age of onset 3-8 yearsabrupt cessation of activity with change of facial expression and blank gazeduration short usually < 15 secondschild returns to normal and no postictal periodautomatisms sometimesactivated by hyperventilation characteristic EEG 3 Hz spike & wavetreat with AEDs (Ethosuxsimide, Valproate, Topamax, and Lamictal)patients usually grow out of seizures by teen years*

3 Hz Spike & Wave*

Also called Janz syndrome First described in 1867Triad includes myoclonic jerks, absence, & tonic clonic seizuresNormal developmentNormal imaging*

A common epilepsy syndrome: 10-15% of all epilepsiesAge of onset 12-18 yearsF=MAccounts for 25% of patients with idiopathic generalized epilepsies. Most have myoclonic jerks, 85% have GTCs, and 15-38% have absence*

EEG with 3-6 Hz multispike and wavePhotosensitivity in 27%-41%Focal EEG abnormalities in up to 55%Triggers: AM wakening, lack of sleep, fatigue, ETOH, and fastingRequires life-long treatmentLittle data on effective treatment

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autonomic dominantonset 3-13yrs with peak 6-8 yearsusually nocturnal or during sleep infrequent episodes that awake the child with drooling, speech arrest, ipsilateral facial twitching or twisted to one side that are only minutes in durationcan sometimes generalizedevelopment and exam are normalcharacteristic EEG that shows Midtemporal (T3,T4) and Central (C3,C4) spikesTreatment usually not indicated if infrequent but can treat with AEDsusually outgrown by 14 years*

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onset 15mos-15years, usually 4-8 yearsinitial seizure manifestations include visual hallucinations (flashing lights), blindness, amaurosis, micropsia, metamorphopsia, loss of consciousness can occurcan have migraine and nausea afterwarddifferent seizure types (GTC, CPS, unilateral clonic) and occur mostly when transitioning from wakefulness to sleepEEG shows occipital spike & wave 1.5-2.5 Hz and eye opening enhances and sleep inhibits*

specific type of seizure seen in infancy and early childhood onset is predominantly in the first year of life, typically < 1 yearcharacteristic EEG called hypsarrhythmiatypical pattern is a sudden bending forward and stiffening of the body, arms, and legs. *

Spasms tend to begin soon after arousal from sleep. Individual spasms typically last for 1 to 5 seconds and occur in clusters, ranging from 2 to 100 spasms at a time. Infantile spasms usually stop by age 5, but are often replaced by other seizure types.West Syndrome is characterized by infantile spasms, hypsarrhythmia, and mental retardation.

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EtiologyCerebral malformations 35%, Perinatal insult 15%, Metabolic 15%, Tuberous Sclerosis 10%Treatment usually starts with AEDs, steroids, ACTH, Vigabatrin, B6, Surgery (if lesions)Prognosis depends on etiology. Worse prognosis with symptomatic as many, 50%, go on to have other types of seizuresMany develop mental retardation or delayed development.*

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Childhood epileptic encephalopathy (Lennox-Gastaut syndrome [LGS]) is a devastating pediatric epilepsy syndrome constituting 1-4% of childhood epilepsiestriad characterized by multiple types of seizures, mental retardation or regression, and characteristic EEGabnormal EEG with generalized slow spike-and-wave discharges (1.5-2 Hz)

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most common seizure types are tonic-axial, atonic, and absence seizures, but myoclonic, generalized tonic-clonic, and partial seizures can be observed. Seizures often are resistant to therapy.mean age at epilepsy onset is 3-5 years (range, 1 d to 14 y)60% have underlying cause (TS, NF, perinatal insult) and 20% have history of Infantile Spasmsdiagnosis by history, PE, and EEGtreatment is difficult*

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Landau-Kleffner Syndromeonset 2-12 yearsacquired aphasia, verbal auditory agnosia, decreased spontaneous speechdifficulty understanding speech and child stops talkingseveral seizure types (GTC, Myoclonic, Absence)neuropsychological disturbances in >50% but intelligence is not affected*

sometimes the child is diagnosed with Autism or being deafEEG is normal during wakefulness but during sleep there is spike & wave mostly in parietal and temporal lobes, sometimes electrical status of sleeptreatment with AEDs and steroids shows good controlrecovery of language is variable and if onset is before 6 years there is better outcomeless than 50% live independent lives*

Landau-Kleffner EEG Shows S&W*

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The concern of the clinician is that epilepsy may be symptomatic of a treatable cerebral lesion. Routine investigation: Haematology, biochemistry (electrolytes, urea and calcium), chest X-ray, electroencephalogram (EEG).Neuroimaging (CT/MRI) should be performed in all persons aged 25 or more presenting with first seizure and in those pts. with focal epilepsy irrespective of age.Specialised neurophysiological investigations: Sleep deprived EEG, video-EEG monitoring.Advanced investigations (in pts. with intractable focal epilepsy where surgery is considered): Neuropsychology, Semiinvasive or invasive EEG recordings, MR Spectroscopy, Positron emission tomography (PET) and ictal Single photon emission computed tomography (SPECT)*

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*To understand epilepsy, it is important to review the difference between epilepsy and seizures. Epilepsy is a generic term used to define a variety of disorders characterized by recurring seizures. A diagnosis of epilepsy means that a person has an underlying condition, such as a brain injury, that affects the delicate systems which govern how electrical energy behaves in the brain, making it susceptible to recurring seizures.

A seizure is a brief, temporary disturbance in the electrical activity of the brain. Seizures are a symptom of epilepsy. However, having a seizure does not necessarily mean that a person has epilepsy. There are other causes of seizures, including high fever, kidney failure, or lack of oxygen.

Epilepsy is not contagious. You cannot catch epilepsy from someone else and nobody can catch it from you. Many misconceptions surround epilepsy, and sometimes people inadvertently add to the negative image of the disorder by choice of language. Like all individuals with a disability, persons with epilepsy dislike labels, such as hes an epileptic. Epilepsy is a condition that a person has, not what they are. The preferred terminology is person with epilepsy. In addition, epilepsy should be referred to as a disorder, since it is not a disease by definition. It is a disorder characterized by a recurring disturbance in the electrical activity of the brain.

*It may surprise you to know that 25 million Americans -- or about one in every ten people -- have had, or will have, a seizure at some point in their lives. You are not alone.

About 2.3 million Americans have epilepsy. In addition, roughly 181,000 new cases of seizures and epilepsy occur each year. Unfortunately, it is estimated that a large number of children and adults have undetected or untreated epilepsy.

Anyone can get epilepsy at any time; however, 50% of people with epilepsy develop seizures by the age of 25. Epilepsy is increasingly common among older people, which, as we will discuss in more detail later, is primarily related to an increase in cardiovascular disease, Alzheimers disease, stroke, and brain tumors. Now, there are as many people with epilepsy 60 years of age and older as children 10 years of age and under.

Question: How many people here know the cause of their epilepsy? If you know, can you share what it is?

*To understand how epilepsy arises, we must briefly outline how the brain functions normally. The brain consists of millions of nerve cells, or neurons, and their supporting structure. Each neuron can get electrical signals from other neurons and pass them on to others. All the functions of the brain, including feeling, seeing, thinking, and moving muscles depend on electrical signals being passed from one neuron to the next, the message being modified as required. The normal brain is constantly generating electrical signals in an orderly way.

In epilepsy, this order is disrupted by some neurons discharging signals inappropriately. There may be a brief electrical storm arising from neurons that are inherently unstable because of a genetic defect (as in the various types of inherited epilepsy), or from neurons made unstable by metabolic abnormalities such as low blood sugar or alcohol. Alternatively, the abnormal discharge may come from a localized area of the brain, as when epilepsy is caused by head injury or brain tumor. A seizure is a massive disruption of the electrical communication between neurons. If enough neurons are involved, the discharge of electrical impulses will produce symptoms. The result could be any number of different sensations or behaviors such as sudden muscle jerk, an abrupt fall, or distorted vision. If the disturbance flashes across the whole brain at once, it could produce a convulsive seizure (convulsion), temporarily disrupting many functions of the brain.

*-Most people with epilepsy wonder what caused their disorder; yet in as many as 7 out of 10 people with epilepsy, no specific cause can be found. Among the rest, the cause may be any one of a number of things that can make a difference in the way the brain works.

Head trauma can occur for a number of reasons, including automobile accidents, gunshot wounds, sports accidents, or falls or blows. The more severe the injury, the greater the risk of developing epilepsy. Lead and alcohol are examples of poisons that can damage the brain. In fact, each year more than 5,000 people have a seizure caused by alcoholism. A number of serious infections and causes of inflammation can lead to brain injury, including meningitis, viral encephalitis, and lupus erythematosus. The brain of a fetus may not develop properly during pregnancy, or a lack of oxygen during birth may damage delicate electrical systems within the brain. Finally, heredity plays a role. People may inherit varying degrees of susceptibility to seizures. This is assumed to be more likely when no other specific cause of seizures can be identified. In seniors, epilepsy may be due to stroke, Alzheimers disease, or other head trauma.

Because the cause is unknown or irreversible in so many people with epilepsy, we need to keep in mind that the important thing is how to live well with a seizure disorder. We need to focus on how to best control the seizures and how to cope with the issues that having a seizure disorder creates.

*Mosby crashs course P127