Seizure Disorders

1. Seizure Disorders
By Dr.Chala R(MD)
March, 2022.
8/20/2022 1

2. Outlines
• Introduction definitions
• epidemiology
• classification of seizures
• eplipsy syndromes
• causes of eplips and seizures
• causes according to age
• basic mechanisms
• approach to the patient
• ddx of seizures
• treatment of seizures
• status eplipticus
• beyond siuzures other mgt iisues
• special issues realted to eplipsy and women
8/20/2022 2

3. Outline
• Seizure
–Introduction
–Epidemiology
–Pathophysiology
–Seizure Classification
–Clinical Features
–Treatment
8/20/2022 3

4. –Status Epilepticus
–Definition
–Treatment
–Refractory Status Epilepticus
Outline
8/20/2022 4

5. Introduction
• Seizure –A seizure is an episode of abnormal neurologic function caused by inappropriate
electrical discharge of brain neurons.
• A seizure (from the Latin sacire, “to take possession of”) is a transient occurrence of signs or
symptoms due to abnormal excessive or synchronous neuronal activity in the brain.
• Epilepsy - a clinical condition in which an individual is subject to recurrent seizures.It describes
a condition in which a person has a risk of recurrent seizures due to a chronic, underlying
process.
• The other definition of epilepsy is two or more unprovoked seizures.
• Status Epilepticus – Seizure Activity for >5 min or 2 or more seizure without regaining
consciousness between seizures
• Status epilepticus refers to continuous seizures or repetitive, discrete seizures with impaired
consciousness in the interictal period. The duration of seizure activity sufficient to meet the
definition of status epilepticus has traditionally been specified as 15–30 min. However, a more
practical definition is to consider status epilepticus as a situation in which the duration of
seizures prompts the acute use of anticonvulsant therapy. For GCSE, this is typically when
8/20/2022 5

6. CONT.....
• Primary or idiopathic seizures are those in which no
evident cause can be identified.
• Secondary seizures are due to an identifiable
neurologic condition.
• Reactive seizures are generally self-limited and not
considered to be a seizure disorder or epilepsy.
8/20/2022 6

7. Epidemology
• Although a variety of factors influence , ~5–10% of the
population will have at least one seizure,
• accounts 1-2% of ED visit
• with the highest incidence occurring in early childhood
and late adulthood.
• the incidence of epilepsy is ~0.3–0.5% in different
populations throughout the world, and the prevalence
of epilepsy has been estimated at 5–30 persons per
1000.
8/20/2022 7

8. prevalence of epilepsy
8/20/2022 8

9. Seizure
• From latin “sacire” to take possession
• Paroxysmal, involuntary neurological event due to
abnormal excessive or synchronous neuronal activity in the
brain
• May be manifested as
– Convulsions
– Experential phenomena not readily picked by
an observer
8/20/2022 9

10. pathophysiology
8/20/2022 10

11. Pathophysiology
• Excitatory stimuli leads to influx of Ca2+
• Depolarization of the neuronal membrane
• Opening of the voltage gated Na channels, influx of sodium
• Generation of repetitive action potential
• Normally an action potential is followed by inhibitory stimuli
such as GABA which hyperpolarized the membrane
• However in a seizure state GABA is blunted causing a bursting
activity in an individual neuron (paroxysmal depolarization
shift)
8/20/2022 11

12. cont.....
• Shift in the normal balance of excitation and inhibition with
the CNS
• Intense, almost simultaneous firing of large number of local
excitatory neurons.
• Bursting in a hyper synchronization of the excitatory burst
across a relatively large cortical region.
• Bursting activity in an individual neuron (Paroxysmal
depolarization shift)
• Generation of repetitive action potentials.
8/20/2022 12

13. why we need to classify
seizure
• for focusing the diagnostic approach on
particular etiologies,
• selecting the appropriate therapy, and
• providing potentially vital information regarding
prognosis.
• to inform risk of
comorbidity/cognitive,psychiatric
8/20/2022 13

14. Classification cont...
1.Where seizure begins (site of onset)
2.Level of awareness during a seizure
3.Other features of seizure
8/20/2022 14

15. By onset
• Focal Seizures – an area or network of cells, one
side of the brain,mainly from sructural
abnormality.
• Generalized – Both side of the
brain,biochemical,cellular,structural
• Unknown onset - inadequate data, can be
classified later
8/20/2022 15

16. By awareness
• Focal Aware
• Focal impaired awareness
• Awareness unknown
8/20/2022 16

17. Seizure Classification by ILAE 2017
8/20/2022 17

18. ILAE 2017
8/20/2022 18

19. FOCAL SEIZURE
• arise from a neuronal network either discretely
localized within one brain region or
• more broadly distributed but still within a cerebral
hemisphere
• EEG in patients with focal seizures is often normal or
may show brief discharges termed epileptiform spikes,
or sharp waves.
• Because focal seizures can arise from the medial
temporal lobe or inferior frontal lobe (i.e., regions
8/20/2022 19

20. 1. WITH INTACT AWARENESS
• motor manifestation-tonic,clonic,myoclonic
• non motor manifestation- sensory, autonomic, or
emotional symptom.
• used to give clues for localization.
• 3 additional feature of motor focal seizure
-“Jacksonian march,”
-Todd’s paralysis
-epilepsia partialis continua
8/20/2022 20

21. CONT...
• Focal seizures-changes in somatic sensation (e.g.,
paresthesias),
–vision (flashing lights or formed hallucinations)
– equilibrium (sensation of falling or vertigo), or
– autonomic function (flushing, sweating, piloerection
 Auras-“internal” events that are not directly
observable by someone else
8/20/2022 21

22. 2.focal seizure with impaired awareness
• start with Aura(with out loss consiousness)
• then motionless stare-in ictal phase
• then impaired awareness followed by automatism
• then transition to full recovery of consciousness may
range from seconds up to an hour or longer.
• post ictal phase-anterograde amnesia,transient
neurologic deficite can also noted.
8/20/2022 22

23. 3.EVOLUTION OF FOCAL SEIZURESTO GENERALIZED
SEIZURES
• can spread to involve both hemisphere and produce
generalized seizure.
• is difficult to differentiate from generalized onset so
needs careful history and EEG studies.
8/20/2022 23

24. GENERALIZED ONSET SEIZURE
• arise at some point in the brain but immediately and
rapidly engage neuronal networks in both cerebral
hemispheres.
1. Typical Absence Seizures ;sudden, brief lapses of
consciousness without loss of postural control.
The seizure usually lasts for only seconds,
consciousness returns as suddenly as it was lost, and
there is no postictal confusion.
8/20/2022 24

25. cont....
• associated with a group of genetically determined
epilepsies with onset usually in childhood (ages 4–10
years) or early adolescence and are the main seizure
type in 15–20% of children with epilepsy.
• can result in day dreaming and poor school
performance and can be clue,
• EEG hallmark is a generalized, symmetric, 3-Hz spike-
and-slow-wave discharges that begins and ends
suddenly, superimposed on a normal EEG background.
8/20/2022 25

26. 2. Atypical Absence Seizures
• features that deviate both clinically and electrophysiologically
from typical absence seizures.
• lapes of consiousness usually longer,less abrupt onset and
cessation, accompanied by more obvious motor signs that
may include focal or lateralizing features.
• EEG shows a generalized, slow spikeand-slow-wave pattern
with a frequency of ≤2.5 per second, as well as other abnormal
activity.
• associated with diffuse or multifocal structural abnrty.
8/20/2022 26

27. 3.GeneralizedTonic-Clonic Seizures
• GTC are the main seizure type
• Seen in 10% of all patients with epilepsy
• Most common type result from metabolic
derangements
8/20/2022 27

28. InitialTonic Phase
• GTC – begin abruptly with initialTonic Phase ,no
Aura
• Laryngospasm – loud moan or “ictic cry”
• Contraction of the Jaw muscles – tongue biting
• Impaired respiration, secretions, cyanosis
• Enhancement of sympathetic tone –Tachycardia,
HTN and Mydriasis
8/20/2022 28

29. Clonic phase and post ictal phase
• Super imposition of muscle relaxation on theTonic
muscle leading to muscle jerking,Last about a minute
• Post ictal phase – unresponsiveness, muscle flaccidity
and excessive salivation,Bowel or bladder incontinence
may occur at this point.
• Gradual gain of consciousness over minutes to many
hours
• Typical post ictal confusion is to be expected
8/20/2022 29

30. cont........
 EEG during the tonic phase of the seizure shows a
progressive increase in generalized low-voltage fast
activity, followed by generalized high-amplitude,
polyspike discharges.
• In the clonic phase, the high-amplitude activity is
typically interrupted by slow waves to create a spike-
and-slow-wave pattern.
 The postictal EEG shows diffuse suppression of all
cerebral activity, then slowing that gradually recovers as
the patient awakens.
8/20/2022 30

31. 4. Atonic Seizures
• sudden loss of postural tone 1-2 sec.
• Consciousness is briefly impaired,no postictal
confusion.
• very brief seizure may cause only a quick head drop or
nodding movement, whereas a longer seizure will
cause the patient to collapse,....head injury
• EEG shows brief, generalized spike-and-wave
discharges followed immediately by diffuse slow waves
that correlate with the loss of muscle tone.
8/20/2022 31

32. 5.Myoclonic Seizures
• sudden and brief muscle contraction that may involve
one part of the body or the entire body.
• Myoclonic seizures usually coexist with other forms of
generalized seizures but are the predominant feature
of juvenile myoclonic epilepsy
• EEG shows bilaterally synchronous spike-and-slow-
wave discharges immediately prior to the movement
and muscle artifact associated with the myoclonus.
8/20/2022 32

33. 6. Epileptic Spasms
• crzed by a briefly sustained flexion or extension of
predominantly proximal muscles, including truncal muscles.
• The EEG usually shows hypsarrhythmia, which consist of
diffuse, giant slow waves with a chaotic background of
irregular, multifocal spikes and sharp waves.
• During spasm- marked suppression of the EEG background
(the “electrodecremental response”).
• The electromyogram (EMG) also reveals crstcs rhomboid
pattern that may help distinguish spasms from brief tonic and
myoclonic seizures. it frequently occur in infants.
8/20/2022 33

34. EPILEPSY SYNDROMES
■ JUVENILE MYOCLONIC EPILEPSY ;crzd by bilateral
myoclonic jerks that may be single or repetitive.
• The myoclonic seizures are most frequent in the
morning after awakening and can be provoked by sleep
deprivation.
• Consciousness is preserved unless the myoclonus is
especially severe. Many patients also experience
generalized tonic-clonic seizures, and up to one-third
have absence seizures.
• seizures usually respond well to appropriate
anticonvulsant medication.
8/20/2022 34

35. LENNOX-GASTAUT SYNDROME
• occurs in children and is defined by the following triad:
1. multiple seizure types (usually including generalized
tonic-clonic, atonic, and atypical absence seizures);
2.an EEG showing slow (<3 Hz) spike-and-wave
discharges and a variety of other abnormalities; and
3. impaired cognitive function in most but not all cases.
8/20/2022 35

36. MESIALTEMPORAL LOBE EPILEPSY
SYNDROME
• MTLE is the most common syndrome associated with focal
seizures with impairment of consciousness and is an example
of an epilepsy syndrome with distinctive clinical,
electroencephalographic, and pathologic features.
• High-resolution (MRI) can detect the characteristic
hippocampal sclerosis that appears to be essential in the
pathophysiology of MTLE for many patients .
• Recognition of this syndrome is especially important because
it tends to be refractory to treatment with anticonvulsants but
responds well to surgical intervention
8/20/2022 36

37. Seizures Etiology
• Toxic causes
• Drugs – e.g MAOi,TCA (overdose or therapeutic levels in pts with
decreased seizure threshold
• Rapid withdrawal of antiepileptics and benzodiazepams
• Chronic alcohol use and abrupt alcohol withdrawal
• CO, Lead, Hg poisoning
• CNS infections – Encephalitis, Menigitis, brain abscess
• Metabolic conditions
• Trauma, CNS space occupying lesions such as BrainTumours
• Familial (mostly absence seizures)
8/20/2022 37

38. causes of seizures by age
8/20/2022 38

39. cont.....
8/20/2022 39

40. Clinical Features
• History
– Characteristic of the seizure activity
– ClinicalContext
•Known epileptic (seizure patterns and precipitants)
•First time – more detailed history (is it really the first
time? Is it really seizure)
•For both classify if provoked or unprovoked
– Associated conditions
•Headache, recent deliveries, systemic illnesses (especially
cancers) etc
8/20/2022 40

41. Algorithm for adult pt with seizure
8/20/2022 41

42. Clinical Features
• Physical Exam
–Vital signs and RBS
–Injuries – head and spine, tongue lacerations, dental
fractures, pulmonary aspirations, shoulder
dislocations
–Neurological exam – serially
–Follow patients level of consciousness and mentation
closely
8/20/2022 42

43. Differential Diagnosis
Seizures Hyperventilation
syndrome
Psychogenic/
Pseudoseizur
es
Movement
Disorders
Abrupt onset and termination
√ X √ X
Period (1 – 2 min)
√ √/X √/X X
Lack of recall
√ X X X
Purposeless movements
√ √ X √
Post ictal confusion
√ X X X
8/20/2022 43

44. LaboratoryTesting
• RBS
• CBC/Serum assay, electroltes
–Prolactin elevated for 15 to 60 min immediately after
seizure
–Anticonvulsive levels – chronic seizures, drug
compliance
• Metablolic panel (ABG) – Lactate driven wide anion gap
acidosis
• Pregnancy test
8/20/2022 44

45. Imaging
• CT – to evaluate for structural lesions in:
-First time attacks
-Or change in established seizure patterns
–MRI
-To rule out tumors or vascular anomalies
–EEG
-Rule out Status Epilepticus in pts with persistent,
unexplained mental status change
8/20/2022 45

46. MECHANISMS OF ACTION OF ANTIEPILEPTIC
DRUGS
1. inhibition of Na+-dependent action potentials in a frequency-
dependent manner (e.g., phenytoin, carbamazepine,
lamotrigine, topiramate, zonisamide, lacosamide,
rufinamide)
2. inhibition of voltage-gatedCa2+ channels (phenytoin,
gabapentin, pregabalin)
3. facilitating the opening of potassium channels (ezogabine)
4. attenuation of glutamate activity (lamotrigine, topiramate,
felbamate
5. potentiation of GABA receptor function (benzodiazepines
8/20/2022 46

47. cont.....
• Two of the effective drugs for absence seizures, ethosuximide
and valproic acid, probably act by inhibitingT-type Ca2+
channels in thalamic neurons.
• In contrast to the relatively large number drugs that can
attenuate seizure activity,currently no drugs known to prevent
the formation of a seizure focus following CNS injury.
• if develop in future important means of preventing the
emergence of epilepsy following injuries such as head trauma,
stroke, and CNS infection.
8/20/2022 47

48. cont....
8/20/2022 48

49. when to initiate
1) an abnormal neurologic examination,
2) seizures presenting as status epilepticus,
3) postictalTodd’s paralysis,
4) a strong family history of seizures, or
5) an abnormal EEG.
• Most patients with one or more of these risk factors
should be treated
8/20/2022 49

50. WHENTO DISCONTINUETHERAPY
1) complete medical control of seizures for 1–5 years;
2) single seizure type, with generalized seizures having a better
prognosis than focal seizures;
3) normal neurologic examination, including intelligence;
4) no family history of epilepsy; and
5) normal EEG.The appropriate seizurefree interval is unknown
and undoubtedly varies for different forms of epilepsy. However,
it seems reasonable to attempt withdrawal of therapy after 2
years in a patient who meets all of the above criteria
8/20/2022 50

51. • when do you start driving after having epilepsy?
8/20/2022 51

52. Treatment of Uncomplicated Seizures
Follow the ABC of live while giving supportive
management
During the attack
• Reduce risk of aspiration – turning pt to the side
When attack subsides
• clear airway
• Assess and management accordingly
8/20/2022 52

53. Patient with a first unprovoked seizure
• Evaluate the underlying cause – most important
predictor of recurrence
• Defer initiation of antiepileptic to the outpatient
department
• Instruct patients on risk minimization from further
seizure attack
• Driving is prohibited till cleared by a neurologist or
primary physician
8/20/2022 53

54. Patients with history of seizure
• Identify and correct potential precipitants that might
have lowered the seizure threshold.
• Advise on the importance of Drugs compliance
• Adjust or change medications if break through seizure
occurred despite adequate medication
• Discharge the patient with a reliable family member or
friend
• Follow up with primary physician should be within 1 to
3 days
8/20/2022 54

55. Special population
• HIV
– Opportunistic infection of the CNS as well as mass lesion,
neurosyphilis are all common in this population and can cause
seizures.
• Neaurocysticercosis
– Most common cause of provoked seizure in the developing world.
• Pregnancy
– Multidisciplinary approach needed. Rule out eclampsia
• Alcohol Abuse
– Missed doses, sleep deprivation, drunken head injuries
– Treat as if first time seizure regardless of seizure hx
8/20/2022 55

56. • what is the tradition behind firing of match during seizure?
8/20/2022 56

57. Status Epilepticus
• Single seizure 5 mins or more in duration or two
or more seizures without recovery of
consciousness between attacks.
• Neurological Emergency
• Can occur in a patient with history of seizures.
• Can be nonconvulsive
• Epilepsia partialis continua – focal tonic clonic
seizure most commonly affect the distal
8/20/2022 57

58. Status Epilepticus
Most common causes
–Sub therapeutic antiepileptic
–Preexisting neuro conditions e.g CNS infection,
head trauma, stroke etc
8/20/2022 58

59. Status EpilepticusTreatment
Goal of treatment (within 5 – 10 min)
• Seizure control
– Establish a large bore IV access, collect lab sample,
administer Fluid and do bedside RBS
– ABC of live should be prioritize – Oxygen, Cadiac
monitor, Pulse Ox
– All of that plus treatment begin all simultaneously
• Consider intubation
– Use short acting sedative here to avoid masking
8/20/2022 59

60. Treatment of Status
Epilepticus
8/20/2022 60

61. Anticonvulsive Drugs in Status
Epilepticus
• 1st line Benzodiazepines
– Most commonly used drugs for temporary control
– Lorazepam 2 – 4 mg IV or Diazepam 5 – 10mg IV (first line)
• 2nd line Anticonvulsants
Phenytoin
– Dose 20mg/kg IV infusion at 50mg per minute,
– monitor BP q5’ to 15’ during infusion and q15’ for one hour
afterwards
– Should not be given with any glucose containing fluid
– Should not be given IM – erratic absorption
8/20/2022 61

62. Anticonvulsive Drugs in Status Epilepticus
Alternative anticonvulsives
– Valproic Acid 20mg/kg IV
• Effective but has serious side effects – hepatic failure and
pancreatitis
– Leveteracitam 20 mg/kg IV
– Very effective, quick to administer
• Locosamide 200mg IV q15’
– Limited availability and limited data
– Give 20mg/Kg IV
8/20/2022 62

63. Refractory Status Epilepticus
• Persistent Seizure activity despite IV administration of
adequate amount of 2 antiepileptic agents
• Usually exceeds 60 mins
• Study – 31% of pts with status epilepticus went on to
develop refractory status epilepticus.
8/20/2022 63

64. Refractory Status Epilepticus
treatment
• Treatment goal - seizure control in less than 30 min
• Start IV meds
• Intubate Pt simultaneously
• Arrange ICU admission
8/20/2022 64

65. Refractory status epilepticusTreatment
• Propofol
• Midazolam
• Barbiturates: Phenobarbital
• Ketamine
• surgical-temporal lobe epilepsy involves resection of the
anteromedial temporal lobe (temporal lobectomy) or a more
limited removal of the underlying hippocampus and amygdala
(amygdalohippocampectomy).
• DBS
8/20/2022 65

66. Reference
• Tintinallis, Emergency Medicine, 9th Ed.
• Harrison’s Principal of Internal Medicine, 20th edition
• Wolf P; Epilepsia partialis continue: A review. Sciencedirect
2019
• GlauserT, Shinar, S, Gloss D, et al: Evidence-based guideline:
treatment of convulsive status epilepticus in children and
adults: report of the guideline committee of theAmerican
Epilepsy Society. Epilepsy Curr 16: 48, 2016.r [PMID; 26900382]
• The International LeagueAgainst Epilepsy: 2017 Revised
Classification of Seizures (retrived from epilepsy.com Jan 27th
8/20/2022 66

67. Thank you
Questions?
8/20/2022 67

68. 8/20/2022 68