A Practical Approach to A Practical Approach to The Diagnosis and The Diagnosis and Evaluation of SeizuresEvaluation of Seizures

Carol Leicher MDCarol Leicher MDConnecticut Children’s Medical CenterConnecticut Children’s Medical Center

University of Connecticut School of University of Connecticut School of MedicineMedicine

Three basic questionsThree basic questions

1. Is it a seizure?1. Is it a seizure?– If so, what kind?If so, what kind?

2. What caused it?2. What caused it? 3. What should be done?3. What should be done?

SeizureSeizure

A seizure is a set of A seizure is a set of clinical symptomsclinical symptoms associated with associated with abnormal electrical abnormal electrical activityactivity in neurons in the cortex of the in neurons in the cortex of the brain.brain.

The clinical characteristics of a seizure are The clinical characteristics of a seizure are the result of the area of the brain that is the result of the area of the brain that is abnormally stimulated.abnormally stimulated.

Epilepsy is a Epilepsy is a clinical condition in which clinical condition in which there are multiple seizures that are there are multiple seizures that are unprovoked.unprovoked.

Types of seizuresTypes of seizures

Generalized seizuresGeneralized seizures

Focal (or partial seizures)Focal (or partial seizures)

Generalized seizuresGeneralized seizures

– Generalized seizures arise from both Generalized seizures arise from both sides of the brain simultaneously. sides of the brain simultaneously. Motor activity is symmetrical and Motor activity is symmetrical and alteration of consciousness occurs.alteration of consciousness occurs.

– Ex. Ex. Primary generalized seizures (grand Primary generalized seizures (grand mal)mal)

Absence seizures (petit mal)Absence seizures (petit mal) Myoclonic seizures, atonic seizuresMyoclonic seizures, atonic seizures

Focal (Partial seizures)Focal (Partial seizures)

Arise from one area of the cortex and Arise from one area of the cortex and may spread to involve adjacent areas or may spread to involve adjacent areas or distant areasdistant areas

Examples:Examples:– Simple partial seizuresSimple partial seizures

Symptoms are referable to the area of the brain Symptoms are referable to the area of the brain involved, no alteration of consciousnessinvolved, no alteration of consciousness

– Complex partial seizuresComplex partial seizures Partial seizures with alteration of consciousnessPartial seizures with alteration of consciousness

– Partial seizures with secondary generalizationPartial seizures with secondary generalization Partial seizure at onset (aura) followed by Partial seizure at onset (aura) followed by

generalized convulsive activitygeneralized convulsive activity

Seizure like episodesSeizure like episodes

SyncopeSyncope– Syncopal seizures may have tonic Syncopal seizures may have tonic

stiffening, clonic jerking and/or post-ictal stiffening, clonic jerking and/or post-ictal confusionconfusion

ParasomniasParasomnias– Sleepwalking, night terrorsSleepwalking, night terrors

HyperventilationHyperventilation Stereotypies/TicsStereotypies/Tics Staring spellsStaring spells

Diagnosis is largely Diagnosis is largely based on the history of based on the history of the event*the event*

Precipitating factorsPrecipitating factors– Position, activity, intercurrent illness, medicationsPosition, activity, intercurrent illness, medications

Description of the episodeDescription of the episode– Eye movements, body movements, one sided or Eye movements, body movements, one sided or

both sides, loss of consciousness or alteration of both sides, loss of consciousness or alteration of consciousness, incontinence, duration, consciousness, incontinence, duration, aftereffectsaftereffects

Predisposing factorsPredisposing factors– Past medical history, recent illness or Past medical history, recent illness or

neurological symptoms, family historyneurological symptoms, family history

*Is it a seizure, if so what kind?*Is it a seizure, if so what kind?

Etiology of SeizureEtiology of Seizure

– Symptomatic seizuresSymptomatic seizures Acute/subacuteAcute/subacute

– Metabolic causes Metabolic causes Hypoglycemia, hypo or hypernatremia, Hypoglycemia, hypo or hypernatremia,

hypocalemiahypocalemia Intoxications/ toxins (lead)Intoxications/ toxins (lead)

– Infectious/InflammatoryInfectious/Inflammatory Meningitis, encephalitis, sepsisMeningitis, encephalitis, sepsis Post-infectious or autoimmune causesPost-infectious or autoimmune causes

– Fever*Fever*– TraumaTrauma– Vascular accidentsVascular accidents

Symptomatic seizures, Symptomatic seizures, part 2part 2

Chronic/ ProgressiveChronic/ Progressive– Remote insultsRemote insults

Perinatal asphyxia or vascular insultPerinatal asphyxia or vascular insult Past head injuryPast head injury

– Developmental brain abnormalitiesDevelopmental brain abnormalities Agenesis of the corpus callosum, Agenesis of the corpus callosum,

schizencephaly, cortical dysplasia schizencephaly, cortical dysplasia – Inborn errors of metabolismInborn errors of metabolism

Storage disorders, amino acid disorders, Storage disorders, amino acid disorders, organic acid disordersorganic acid disorders

– Neurocutaneous disordersNeurocutaneous disorders– Cerebral degenerative diseasesCerebral degenerative diseases

Idiopathic seizuresIdiopathic seizures

The cause of the seizure can not be The cause of the seizure can not be determined by conventional testing determined by conventional testing oror

Seizures of genetic origin in which Seizures of genetic origin in which seizures are the only manifestation.seizures are the only manifestation.

This category may comprise as This category may comprise as much as 60% of all childhood much as 60% of all childhood seizure disorders.seizure disorders.

Determining the cause Determining the cause of a child’s seizure(s) *of a child’s seizure(s) * HistoryHistory

– Associated symptoms, intercurrent illness, recent Associated symptoms, intercurrent illness, recent medications, exposures (drugs,toxins, pets), past medical medications, exposures (drugs,toxins, pets), past medical history ( birth history, developmental history, family history ( birth history, developmental history, family history)history)

ExaminationExamination– Fever or other abnormal vital signsFever or other abnormal vital signs– Head size, skin abnormalities (hypo/hyperpigmented Head size, skin abnormalities (hypo/hyperpigmented

areas) ,menigismus, asymmetry of the face or the areas) ,menigismus, asymmetry of the face or the extremities, enlarged organs, dysmorphic featuresextremities, enlarged organs, dysmorphic features

– Alteration of mental status, cranial nerve abnormalities, Alteration of mental status, cranial nerve abnormalities, motor tone or strength or reflex changes, gait motor tone or strength or reflex changes, gait abnormalities,ataxia, sensory abnormalities.abnormalities,ataxia, sensory abnormalities.

*What caused it?*What caused it?

Diagnostic StudiesDiagnostic Studies

BloodworkBloodwork - - electrolytes, Ca, glucoseelectrolytes, Ca, glucose UrineUrine- - toxicology, amino acid and organic acid toxicology, amino acid and organic acid

measurement*measurement* EEGEEG

– Useful for evaluating interictal abnormalitiesUseful for evaluating interictal abnormalities– Occasionally useful for determining nature of a Occasionally useful for determining nature of a

clinical symptom (absence seizures, tics or clinical symptom (absence seizures, tics or other frequent movements)other frequent movements)

– Helpful in predicting recurrence of seizures.Helpful in predicting recurrence of seizures.– A normal EEG does not exclude a diagnosis of A normal EEG does not exclude a diagnosis of

seizureseizure..

Diagnostic studies #2Diagnostic studies #2

Ambulatory EEGAmbulatory EEG– Allows for Ictal recording- ie, EEG activity Allows for Ictal recording- ie, EEG activity

during a suspected episodeduring a suspected episode Drawbacks- technical, availability, depends on Drawbacks- technical, availability, depends on

patient/parent to indicate when the episodes are patient/parent to indicate when the episodes are occurringoccurring

VideotelemetryVideotelemetry– Simultaneous recording of EEG and video of Simultaneous recording of EEG and video of

patient. patient. – Can be done as a day procedure or as Can be done as a day procedure or as

inpatientinpatient– Episodes must occur with some frequencyEpisodes must occur with some frequency

Diagnostic Studies#3Diagnostic Studies#3

Imaging proceduresImaging procedures– CTT is not the procedure of choice but is CTT is not the procedure of choice but is

appropriate in emergencies, especially appropriate in emergencies, especially traumatrauma

– MRI is the imaging procedure of choiceMRI is the imaging procedure of choice Abnormal neurological examinationAbnormal neurological examination Focal seizure activityFocal seizure activity Focal findings on EEGFocal findings on EEG

– PET scanning is a specialized procedure PET scanning is a specialized procedure done in limited circumstances (usually as done in limited circumstances (usually as part of evaluation of intractable seizures or part of evaluation of intractable seizures or when a surgical treatment is proposed.when a surgical treatment is proposed.

Treatment Decisions*Treatment Decisions*

The decision to treat depends on The decision to treat depends on evaluation of risks and benefitsevaluation of risks and benefits– Risk of subsequent seizuresRisk of subsequent seizures– Risk of treatmentRisk of treatment– Particular circumstances of patientParticular circumstances of patient

– *What to do about it?*What to do about it?

Risks of further Risks of further seizuresseizures Risk of a second seizure is 20-30% if:Risk of a second seizure is 20-30% if:

– Examination, EEG and CTT (imaging study) Examination, EEG and CTT (imaging study) is normal (and careful review of history is normal (and careful review of history discloses no other events)discloses no other events)

– Exceptions: Absence seizures. Myoclonic Exceptions: Absence seizures. Myoclonic seizuresseizures

Risk of a second seizure if EEG is Risk of a second seizure if EEG is abnormal is 60%abnormal is 60%

Risk of a third seizure is 70% Risk of a third seizure is 70%

Risk of having another Risk of having another seizureseizure Most seizures do not produce Most seizures do not produce

injury to the brain.injury to the brain. Seizures in a bad place- bath, driving a Seizures in a bad place- bath, driving a

car, climbing, riding a bicycle etc.car, climbing, riding a bicycle etc. Prolonged seizure which can lead to Prolonged seizure which can lead to

hypoxia or secondary complications.hypoxia or secondary complications. Sudden unexplained death- a very rare Sudden unexplained death- a very rare

complication of seizures, particularly in complication of seizures, particularly in children. children.

Risk of treatmentRisk of treatment

Medication side effectsMedication side effects– Severe- liver failure, aplastic Severe- liver failure, aplastic

anemia, severe allergic reaction anemia, severe allergic reaction (Stevens-Johnson syndrome)(Stevens-Johnson syndrome)

– Decreased alertness, Decreased alertness, personality/behavior changes, personality/behavior changes, weight loss/gainweight loss/gain

Social stigmaSocial stigma

TreatmentTreatment

Discuss risks and benefits with patient and Discuss risks and benefits with patient and parent based on available statisticsparent based on available statistics

If 1st seizure with lower risk of recurrence, If 1st seizure with lower risk of recurrence, consider no treatment. consider no treatment.

Use of rectal valium as a “rescue measure”Use of rectal valium as a “rescue measure” If decision to treat, choose a medication If decision to treat, choose a medication

based on seizure type, age of patient and based on seizure type, age of patient and side effect profile.side effect profile.

Monotherapy is generally preferable, Monotherapy is generally preferable, especially in first line treatment.especially in first line treatment.

Anticonvulsant Anticonvulsant medicationsmedications Generalized Generalized

seizuresseizures Divalproex sodiumDivalproex sodium ZonisamideZonisamide TopiramateTopiramate LamotrigineLamotrigine LevetiracetamLevetiracetam RufinamideRufinamide Ethosuximide*Ethosuximide*

Partial SeizuresPartial Seizures– CarbamazepineCarbamazepine– OxycarbazepineOxycarbazepine– ZonisamideZonisamide– TopiramateTopiramate– LevetiracetamLevetiracetam– LamotrigineLamotrigine– PhenytoinPhenytoin– Phenobarbital*Phenobarbital*

Other Treatment Other Treatment AlternativesAlternatives

Dietary treatmentDietary treatment– Ketogenic dietKetogenic diet– Modified Atkins dietModified Atkins diet

Surgical treatmentSurgical treatment– Vagal nerve stimulatorVagal nerve stimulator– Surgical removal of seizure focusSurgical removal of seizure focus

AlgorithmAlgorithm

Initial Event

History- eyewitness report if possible

Physical Examination

EEG, imaging study if EEG focal

If isolated event, no treatment or Rectal valium

If multiple episodes discuss medication

Normal Abnormal

Probable seizure Other Another lecture

EEG,Imaging study, consider more emergent evaluation

Historical CluesHistorical Clues

Precipitating factorsPrecipitating factors– Seizures may be precipitated by flashing Seizures may be precipitated by flashing

lights, hyperventilation, illness or being lights, hyperventilation, illness or being overtired (stress?)overtired (stress?)

– Syncope is precipitated by standing up, Syncope is precipitated by standing up, being overheated, sight of blood, being overheated, sight of blood, frightening eventfrightening event

State of alertness-State of alertness- syncope doesn’t occur in syncope doesn’t occur in sleep, Seizures may occur in sleep or sleep, Seizures may occur in sleep or wakefulness. Parasomnias only occur in sleep.wakefulness. Parasomnias only occur in sleep.

Further historical cuesFurther historical cues

Position- Position- seizures may occur in any position, seizures may occur in any position, syncope usually occurs when sitting or syncope usually occurs when sitting or standingstanding

Eye movements- Eye movements- eyes are usually closed or eyes are usually closed or partially open during a syncopal episode, more partially open during a syncopal episode, more likely to be open during a seizure. The likely to be open during a seizure. The presence of deviation of the eyes to one side presence of deviation of the eyes to one side or another suggests a partial seizure.or another suggests a partial seizure.

Seizures Seizures that affect one side of the body more that affect one side of the body more than the other are likely to be focal in origin. than the other are likely to be focal in origin. Syncopal episodes are usually symmetricalSyncopal episodes are usually symmetrical..

Staring vs. Absence Staring vs. Absence vs. Partial Complex vs. Partial Complex seizuresseizures Staring spells are more apt to occur when the Staring spells are more apt to occur when the

patient is passive, listening to a teacher, or parent patient is passive, listening to a teacher, or parent or watching TV. They can be of indeterminate or watching TV. They can be of indeterminate length and are interruptible by voice or touch.length and are interruptible by voice or touch.

Absence seizures can occur in the midst of Absence seizures can occur in the midst of activity, usually brief 10-20 seconds. There may activity, usually brief 10-20 seconds. There may be eye blinking/fluttering or subtle head be eye blinking/fluttering or subtle head movements. The patient recovers very quickly. movements. The patient recovers very quickly. Incontinence may occur.Incontinence may occur.

Partial complex seizures are usually 1-2 minutes Partial complex seizures are usually 1-2 minutes in length, and can not be interrupted. There are in length, and can not be interrupted. There are often stereotypic movements and postictal often stereotypic movements and postictal confusion is common.confusion is common.

Generalized seizures vs Generalized seizures vs Partial Seizures Partial Seizures Generalized seizures have sudden onset Generalized seizures have sudden onset

without warning. Motor symptoms are without warning. Motor symptoms are symmetrical. Postictal state is common symmetrical. Postictal state is common when there is convulsive activity but when there is convulsive activity but not for absence or myoclonic seizuresnot for absence or myoclonic seizures

Partial seizures may begin with Partial seizures may begin with localized symptoms that the patient is localized symptoms that the patient is aware of (aura) and may have aware of (aura) and may have asymmetric motor symptoms. Postictal asymmetric motor symptoms. Postictal state is common, even without state is common, even without convulsive activity.convulsive activity.

AlgorithmAlgorithmAlgorithmAlgorithm

Initial Event

History- eyewitness report if possible

Physical Examination

EEG, imaging study if EEG focal

If isolated event, no treatment or Rectal valium

If multiple episodes discuss medication

Normal Abnormal

Probable seizure Other Another lecture

EEG,Imaging study, consider more emergent evaluation