convulsive disorders
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Convulsive Convulsive DisordersDisorders
Alina Valdes, M.D.
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EpilepsyEpilepsyChronicChronic conditionconditionSeizures characterized by sudden and
unusually unprovoked attackssubjective experiential phenomenaaltered consciousnessinvoluntary movements
SeizuresSeizuresResult from abnormal brain electrical activityCommon sign of brain dysfunction
Not all seizures imply epilepsyNot all seizures imply epilepsy
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CausesCausesReversible medical or neurologic illness Reversible medical or neurologic illness – symptomatic seizuresUsually self-limitedSeizures resolve if underlying disorder corrected
Physiologic stress Physiologic stress (e.g., sleep deprivation), , fever, and alcohol or sedative drug fever, and alcohol or sedative drug withdrawalwithdrawalLowered seizure threshold
Genetic factorsGenetic factorsUnrecognized previous CNS injuryUnrecognized previous CNS injuryUnknownUnknown
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Causes of Symptomatic Causes of Symptomatic SeizuresSeizures
Acute electrolyte disordersAcute electrolyte disordersNa <120 or >155 mEq/LOsmolality > 310 mOsm/LCa < 7 mg/dl
DrugsDrugs INH, PCN’s, theophylline, ephedrine, lidocaine,
TCA’s, cocaine, amphetamines, EtOH withdrawal
CNS diseaseCNS diseaseHypertensive/hepatic encephalopathy, eclampsia,
SLE, meningitis, stroke, sickle cell disease, brain tumor
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EtiologyEtiologyCan begin at any time of lifeCan begin at any time of life
Incidence higher among young Incidence higher among young children and elderlychildren and elderly
Incidence higher in developing Incidence higher in developing countries and inner-city areascountries and inner-city areas
About 70% of adults and 40% of About 70% of adults and 40% of children with new-onset epilepsy have children with new-onset epilepsy have partial partial (focal) seizures seizuresImply cerebral injury or lesion
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In childrenIn childrenIdiopathic/cryptogenic: 67%Congenital: 20%Trauma, infection, vascular, neoplastic,
degenerative
In adultsIn adultsIdiopathic/cryptogenic: 55%Vascular: 15%Neoplastic, trauma, degenerative,
congenital, infection
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ClassificationClassificationInternational League Against EpilepsyInternational League Against EpilepsyClassified by clinical symptoms and Classified by clinical symptoms and signssignsManifestations depend onManifestations depend onWhether most or only part of cerebral cortex
involved at beginningFunctions of cortical areas where originatesSubsequent pattern of spread
Seizures are dynamic and evolve Seizures are dynamic and evolve depending on extent and manner of depending on extent and manner of spread of electrical dischargespread of electrical discharge
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International League International League Against Epilepsy Against Epilepsy
ClassificationClassificationClassification of SeizuresClassification of SeizuresPartial (Focal) Seizures
Simple partial seizures (consciousness not impaired)
with motormotor signswith sensorysensory signswith psychiatricpsychiatric symptomswith autonomicautonomic symptoms
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Complex partial seizures (consciousness is impaired)
simple partial onset followed by impaired consciousness
with impairment of consciousness at onset
with automatismsPartial seizures evolving to secondarily generalized seizures
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Generalized Seizures of Nonfocal OriginAbsence seizuresMyoclonic seizures; myoclonic jerks (single or multiple)
Tonic-clonic seizuresTonic seizuresAtonic seizures
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Classification of Epileptic Classification of Epileptic SyndromesSyndromesIdiopathic Epilepsy Syndromes
(Focal or Generalized)Benign neonatal convulsionsBenign partial epilepsy of childhoodChildhood absence epilepsyJuvenile myoclonic epilepsyIdiopathic epilepsy, otherwise unspecified
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Symptomatic Epilepsy Syndromes (Focal or Generalized)West’s syndrome (infantile spasms)Lennox-Gastaut syndromePartial continuous epilepsyTemporal lobe epilepsyFrontal lobe epilepsyPost-traumatic epilepsy
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Other Epilepsy Syndromes of Uncertain or Mixed ClassificationNeonatal seizuresFebrile seizuresReflex epilepsyAdult nonconvulsive status epilepticus
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Partial SeizuresPartial SeizuresSimple partialSimple partialEpileptic electrical discharge limited to focal
area of cortexPatients can interact normally with their
environment except for limitations on localized brain function
Include subjective sensory and psychological phenomena
Auras affect about 60% of patients with focal epilepsy
Location of focus often predicts nature of pathology and directs testing
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With With motormotor signs signsBegin with clonic (rhythmic jerking) or tonic
(stiffening) movements in body partLarge cortical representation
involves muscles of face and hand “Jacksonian march” – uncommon
homunculus representation: begins in primary motor cortex and spreads to involve rest of precentral gyrus
“Fencer’s posture” – commonictal discharges involve secondary motor areas
of frontal lobecontralateral flexion and elevation of arm,
contralateral turning of head and eyes, and tonic expression of ipsilateral arm
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Speech arrest, vocalizations, and eye blinking
Todd’s paralysisTransient neurologic abnormality – last
<48 hoursPostictal depression of epileptogenic
cortical areamotor seizure – focal weaknesssensory seizure – numbnessoccipital lobe seizure – blindness
Focal abnormalities useful clues to site of origin
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Complex PartialComplex PartialImpair consciousness and produce
unresponsiveness70% to 80% arise from temporal lobeRemaining cases arise mainly from frontal
lobeMany evolve from simple partial as
progressesUncinate fits
preceded by olfactory auraarise in or near uncus of temporal lobe
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Generalized SeizuresGeneralized Seizures
Begin diffusely and involve both Begin diffusely and involve both cerebral hemispheres cerebral hemispheres simultaneously from outsetsimultaneously from outsetSubdivided on basis of motor Subdivided on basis of motor manifestationsmanifestationsMust be distinguished from focal Must be distinguished from focal seizures that become secondary seizures that become secondary generalizedgeneralized
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Generalized tonic-clonicGeneralized tonic-clonic Grand mal convulsions
1. abrupt LOC
2. bilateral tonic extension of trunk and limbs (tonic phase)
3. loud vocalization (“epileptic cry”)
4. bilaterally synchronous muscle jerking (clonic phase)
Urinary incontinence common Fecal incontinence rare Seizure itself not usually last >90 seconds
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Postictal phase
1. transient deep stupor
2. 15-30 minutes lethargic, confused state with automatic behavior
3. with recovery, patients complain of headache, muscle soreness, mental dulling, lack of energy, or mood changes for as long as 24 hours
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Physiologic changes – transientBlood hypoxia, lactic acidosisElevated plasma catecholaminesIncreased serum CPK, prolactin, corticotropin, cortisol, Beta-endorphin, and GH
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ComplicationsOral traumaVertebral compression fracturesShoulder dislocationAspiration pneumoniaSudden death – acute pulmonary edema, cardiac arrhythmia, suffocation
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AbsenceAbsencePetit mal seizuresMainly in childrenSudden, momentary lapses in awareness,
staring, rhythmic blinking, and few small clonic jerks of arms or hands
Immediate return to normalNo postictal periodUsually no recollection of seizureMost last <10 seconds
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Atypical absenceAtypical absenceMore gradual lapses of awarenessNot resolve as abruptlyAutonomic features or loss of muscle toneMost often in mentally retarded childrenNot respond as well to drugs
MyoclonicMyoclonicRapid, recurrent, brief muscle jerksCan occur bilaterally, synchronously or
asynchronously, or unilaterally without LOCOften cluster shortly after waking or while
falling asleep
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AtonicAtonic“Drop attacks”Most often in children with diffuse
encephalopathiesSudden loss of muscle tone
falls with self-injury
ReflexReflexPrecipitated by specific stimulus
touch, musical tune, reading, etc.
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Febrile SeizuresFebrile SeizuresMost common cause of convulsions in Most common cause of convulsions in childrenchildren
Most occur between ages of 6 months and 4 Most occur between ages of 6 months and 4 yearsyears
About 30% of the children have more than About 30% of the children have more than one attackone attack
Greatest chance of recurrence if seizure <1 Greatest chance of recurrence if seizure <1 y.o. or family historyy.o. or family history
Most times no long-term consequences but Most times no long-term consequences but increase risk of developing epilepsy laterincrease risk of developing epilepsy later
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Benign Partial Epilepsy of Benign Partial Epilepsy of Childhood With Central-Childhood With Central-
Midtemporal SpikesMidtemporal SpikesRolandic epilepsyRolandic epilepsy
One of most common in childrenOne of most common in children 15% of all pediatric epilepsies
Usually begin between 4 and 13 years old and Usually begin between 4 and 13 years old and disappear by mid to late adolescencedisappear by mid to late adolescence
Seizures principally at nightSeizures principally at night
EEG shows stereotyped epileptiform discharges EEG shows stereotyped epileptiform discharges over central and midtemporal regionsover central and midtemporal regions
Outcome not affected by treatmentOutcome not affected by treatment
Carbamazepine prevents recurrent attacksCarbamazepine prevents recurrent attacks
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Juvenile Myoclonic Juvenile Myoclonic EpilepsyEpilepsy
Idiopathic generalized epilepsyIdiopathic generalized epilepsyMost often begins between 8 and 20 Most often begins between 8 and 20 years oldyears oldMorning myoclonic jerks, generalized Morning myoclonic jerks, generalized tonic-clonic seizures occurring just tonic-clonic seizures occurring just after awakeningafter awakeningFamily history of similar seizuresFamily history of similar seizures
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Lennox-Gastaut Lennox-Gastaut SyndromeSyndrome
Heterogeneous group of early Heterogeneous group of early childhood epileptic encephalopathieschildhood epileptic encephalopathies
Physical brain abnormalitiesPhysical brain abnormalities
Mental retardationMental retardation
Uncontrolled seizuresUncontrolled seizures
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Temporal Lobe EpilepsyTemporal Lobe EpilepsyMost common cause in adultsMost common cause in adultsAt least 40% of epilepsy cases
Begin in late childhood/adolescenceBegin in late childhood/adolescence
Often history of febrile seizuresOften history of febrile seizures
Almost all patients have complex Almost all patients have complex partial seizures, some secondarily partial seizures, some secondarily generalizegeneralize
Most often arises from mesial Most often arises from mesial temporal lesion temporal lesion – hippocampal sclerosis
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Post-Traumatic EpilepsyPost-Traumatic EpilepsyDirectly related to severity of head Directly related to severity of head injuryinjuryCerebral contusionIntracerebral or intracranial hematomaUnconsciousness or amnesia >24 hoursPersistent abnormalities on neuro exam2/3 of patients have partial or secondary
generalized
Mild head injuries not increase riskMild head injuries not increase risk
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DiagnosisDiagnosisEvaluationEvaluation
1. Determine if patient has epilepsy
2. Classify the seizures – if clinical data fit syndrome
3. Identify underlying cause
History – patient or witness descriptionHistory – patient or witness description Setting, previous history, pattern
Physical exam normal in most casesPhysical exam normal in most cases Skin, retina, focal neurologic signs Absence seizures can be triggered by
hyperventilation
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Lab Tests – EEGLab Tests – EEGMost important for epilepsyMost important for epilepsyEstablishing diagnosisClassifying seizuresIdentifying syndromesMaking treatment decisions
Epileptiform patterns Epileptiform patterns – spikes or sharp wavesFocal vs. generalized activity
Establish epilepsy only if record Establish epilepsy only if record characteristic discharge during characteristic discharge during representative clinical attackrepresentative clinical attack
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40% - 50% of epileptics have 40% - 50% of epileptics have abnormalities on initial EEGabnormalities on initial EEG
Increase chance of capturing by Increase chance of capturing by sleep deprivation 24 hours before sleep deprivation 24 hours before test and sleep during a portion of test and sleep during a portion of recordingrecording
Serial EEG’s increase yield Serial EEG’s increase yield
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electroencephalographyelectroencephalography
Brainwave PatternsBrainwave Patterns The electrical activity of the brain was first demonstrated in 1929 by the The electrical activity of the brain was first demonstrated in 1929 by the German psychiatrist Hans Berger. The scientific professions were slow in German psychiatrist Hans Berger. The scientific professions were slow in giving proper attention to Berger's discovery of the brain rhythms he giving proper attention to Berger's discovery of the brain rhythms he named alpha waves, but since then at least three other standard named alpha waves, but since then at least three other standard brainwave patterns have been isolated and identified. Alpha waves are brainwave patterns have been isolated and identified. Alpha waves are fast, medium-amplitude oscillations, now known to represent the fast, medium-amplitude oscillations, now known to represent the background activity of the brain in the physically and psychologically background activity of the brain in the physically and psychologically healthy adult. They are most characteristically visible during dream-sleep healthy adult. They are most characteristically visible during dream-sleep or when a subject is relaxing with eyes closed. Delta waves are large, or when a subject is relaxing with eyes closed. Delta waves are large, slow-moving, regular waves, typically associated with the deepest levels slow-moving, regular waves, typically associated with the deepest levels of sleep. In children up to the age of puberty the appearance of high-of sleep. In children up to the age of puberty the appearance of high-amplitude theta waves, having a velocity between those of alpha and amplitude theta waves, having a velocity between those of alpha and delta rhythms, usually signals the onset of emotional stimulation. The delta rhythms, usually signals the onset of emotional stimulation. The presence of theta waves in adults may be a sign of brain damage or of an presence of theta waves in adults may be a sign of brain damage or of an immature personality. Beta rhythms are small, very fast wave patterns immature personality. Beta rhythms are small, very fast wave patterns that indicate intense physiological stress, such as that resulting from that indicate intense physiological stress, such as that resulting from barbiturate intoxification.barbiturate intoxification.
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Neuroimaging StudiesNeuroimaging StudiesBrain MRIBrain MRIIdentifies structural lesions that may be
relatedObtain complete study: T1- and T2-
weighted images in coronal and axial planes
Should be obtained in all adults with epilepsy and children with partial seizures, abnormal neuro findings, or focal slow-wave abnormalities on EEG
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PET and SPECTPET and SPECTFunctional views of brainPhysiologically active, radiolabeled
tracersMetabolic activity – PETBlood flow – SPECT
Abnormalities often seen when MRI normal
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Other TestsOther TestsRoutine bloods not helpfulRoutine bloods not helpful
Baseline electrolytes,LFT’s, cbc prior to Baseline electrolytes,LFT’s, cbc prior to treatmenttreatment
Bloods in older patients with acute or Bloods in older patients with acute or chronic diseasechronic disease
Drug screen for substance abuse if Drug screen for substance abuse if unexplained generalized seizuresunexplained generalized seizures
Lumbar puncture only if suspect Lumbar puncture only if suspect meningitis or encephalitis meningitis or encephalitis – repeated seizures may increase CSF protein and wbc’s
EKG if history EKG if history – arrhythmia, valvular disease
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Differential DiagnosisDifferential DiagnosisMisdiagnosis Misdiagnosis – not respond to treatmentNonepileptic paroxysmal Nonepileptic paroxysmal disordersdisordersSudden, discrete events with abnormal
behavior, variable responsiveness, changes in muscle tone, and various postures or movements
More common and variable in presentation in children
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Disorders That May Disorders That May Resemble SeizuresResemble Seizures
Movement disorders: Movement disorders: myoclonus, episodic ataxiasMigraine: Migraine: confusional, vertebrobasilarSyncopeSyncopeBehavioral and psychiatric disorders: Behavioral and psychiatric disorders: panic, hyperventilation, dissociation CataplexyCataplexyTIATIAAlcoholic blackoutsAlcoholic blackoutsHypoglycemiaHypoglycemia
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SyncopeSyncopeTransient global decrease in cerebral perfusionLOC lasts seconds with rapid recoveryConvulsive syncope: if ischemia severe, may
get brief tonic posturing or clonic jerks of arms and legs
MigraineMigraineEspecially basilar artery migraine in adolescents
and young adults: lethargy, mood changes, confusion, disorientation, vertigo, bilateral visual disturbances, and LOC
Panic attacksPanic attacksMuscle twitching or spasms with hyperventilationPatients may faint
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TreatmentTreatmentCorrect underlying cause if possibleCorrect underlying cause if possibleIf seizures recurrent, try to stop attacks If seizures recurrent, try to stop attacks with antiepileptic drugs:with antiepileptic drugs:
1. Define type of seizure and give indicated medication in increasing doses until either control seizures or side effects occur
2. Infrequent seizures treated with slow dose changes
3. Pick another agent if persistent seizures or major side effect
4. Add another drug before stop first to prevent status epilepticus
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5. If seizures persist after tried two agents to toxicity, refer to specialist
6. Seizures can be caused by toxic levels of antiepileptics (especially phenytoin and carbamazepine
Surgery:Surgery: For medically intractable epilepsy: about
20% of patients Can eliminate seizures and restore normal
neuro function in selected patients Must accurately locate seizure focus
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Drugs in TreatmentDrugs in Treatment
Simple and complex partial and secondary Simple and complex partial and secondary generalizedgeneralizedCarbamazepine, phenytoin, valproate, gabapentin,
lamotrigine, topiramate
Primary generalizedPrimary generalizedTonic-clonic: valproate, carbamazepine,
phenytoin, lamotrigineAbsence: ethosuximide, valproate, lamotrigineMyoclonic and tonic: valproate, clonazepam
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Status EpilepticusStatus Epilepticus
Major generalized motor statusMajor generalized motor statusSeizures follow one another quickly
that patient not have chance to recoverCan cause brain damageMost common cause is abrupt
anticonvulsant medication withdrawal
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Other causes:alcohol or drug withdrawal from abusercerebral infectiontraumahemorrhageneoplasm
Treatment is urgentCause must be sought
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Partial motor statusPartial motor statusPartial continuous epilepsyUncommonCan last for hours, days, or longerSeizure frequency range from one every
three seconds to several per secondMotor attacks range from highly focal,
myoclonic twitches to jerks that involve half of body
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Cerebral lesions cause in face or distal upper extremity
Brain stem or spinal cord lesions cause proximal myoclonic activity
Causes:severe hyperglycemia – can also produce
partial complexstroketraumaneoplasmsencephalitisunknown
Often resistant to treatment
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Partial complex statusPartial complex statusSustained state of confusion with
stereotyped motor and autonomic automatisms: hours to days
May have abrupt-onset schizophreniform or other bizarre activity
Patients may resist help in abnormal stateEEG: continuous, usually asymmetric slow
and spike activity over temporal lobe(s)Treat rapidly due to possible memory and
intellect impairment
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Absence statusAbsence statusPetit mal statusTwo formsMore common form similar to partial
complex statusconfused automatic behaviorclosely spaced or continuous runs of 3- to 4-Hz
spike and wave activity on EEGoccurs mostly in adolescents with known petit
malmost episodes last <30 minutesmost stopped with IV diazepam
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PregnancyPregnancy >90% of women on antiseizure meds have >90% of women on antiseizure meds have healthy infantshealthy infantsHereditary risks to fetusHereditary risks to fetusWomen have higher risks of complications Women have higher risks of complications of pregnancyof pregnancyAnticonvulsant meds need readjustment Anticonvulsant meds need readjustment due to changes in blood volume and drug due to changes in blood volume and drug interactionsinteractionsBreast feeding not contraindicated if taking Breast feeding not contraindicated if taking medsmedsNot discontinue meds during pregnancy Not discontinue meds during pregnancy but can consider prior to conceptionbut can consider prior to conception
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PrognosisPrognosis
60% to 70% of people with epilepsy 60% to 70% of people with epilepsy have 5-year remission of seizures have 5-year remission of seizures within 10 years of diagnosiswithin 10 years of diagnosisAbout half of these seizure-free About half of these seizure-free without medswithout medsIdiopathic epilepsyNormal neuro examOnset in early to middle childhood
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Discontinuing DrugsDiscontinuing Drugs
Many patients seizure-free on medsMany patients seizure-free on medsSome can stop meds and remain Some can stop meds and remain seizure-freeseizure-freeControlled with monotherapyFew seizuresNormal EEG and neuro exam prior to
stopping medsSeizure-free interval of at least 4 years
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