Seizures and Epilepsy

1. Seizures and Epilepsy Presented by Chan Hau Yee Chan Wai Chung Kwok Vansie Lee Kin Tong

2. Seizure VS Epilepsy What is the difference? • Seizure: • manifestation of paroxysmal involuntary disturbance of brain function • Abnormality/dysfunction of • Consciousness, motor activity, behaviour, sensory, or autonomic functions • Epilepsy: • Recurrent seizures • Unrelated to fever or to an acute cerebral insult

3. Local Data • The period prevalence rate of epilepsy in 1997 (January to December) is estimated to be 4.5 per 1000 children aged < 19 years • Wong V. Study of seizure and epilepsy in Chinese children in Hong Kong: period prevalence and patterns. J Child Neurol. 2004 Jan;19(1):19-25

4. Classification of seizures • Partial seizure (55.4%) • Generalized seizure(38.7%) • Unclassified • Epilepsy syndrome Fong GC, et al. A prevalence study of epilepsy in Hong Kong. Hong Kong Med J. 2003 Aug;9(4):252-7. • What is the difference between partial and generalised seizures?

5. Partial Seizure • Simple partial • With motor signs • With somatosensory or special symptoms • With autonomic symptoms • With psychic symptoms • Complex partial • Partial seizure with secondary generalisation How can we differentiate between simple partial and complex partial seizure?

6. Simple partial seizure Complex partial seizure Consciousness Conscious Impaired Duration 10-20s 1- 2 min Aura + +/- Automatisms - Common Post-ictal phenomenon - + EEG Spikes or sharp waves bilaterally or unilaterally or a multifocal spike pattern Interictal EEG anterior temporal lobe sharp waves or focal spikes and multifocal spikes (80%)

7. Generalized seizure • Absence • Myoclonic • Clonic • Tonic • Tonic-clonic • atonic

8. Status epilepticus • Consciousness does not return in between attacks • Lasts more than 30 mins • May be life threatening • Terminate the seizure as soon as possible

9. Category Localization-related Generalized Idiopathic (42%) Benign epilepsy of childhood with centrotemporal spikes(benign rolandic epilepsy)Benign occipital epilepsy Benign familial neonatal convulsionsBenign myoclonic epilepsy in infancyChildhood absence epilepsyJuvenile absence epilepsyJuvenile myoclonic epilepsyEpilepsy with generalized tonic-clonic seizures on awakening Symptomatic (of underlying structural disease) (40.8%) Temporal lobeFrontal lobeParietal lobeOccipital lobe Early myoclonic encephalopathyEarly infantile epileptic encephalopathywith suppression-burst (Ohtahara syndrome)Cortical dysgenesisMetabolic abnormalitiesWest syndromeLennox-Gastaut syndrome Cryptogenic (16.8%) Any occurrence of partial seizures without obvious pathology Epilepsy with myoclonic-astatic seizuresEpilepsy with myoclonic absencesWest syndrome (with unidentified pathology)Lennox-Gastaut syndrome (with unidentified pathology)

10. Cont’d (Epilepsy Syndromes) • Special syndromes • Febrile convulsions • Isolated unprovoked seizures or isolated status epilepticus • Seizures occurring only with toxic or metabolic provoking factors • Neonatal seizures of any etiology • Epilepsy with continuous spike-wave of slow wave sleep (electrical status epilepticus of sleep) • Acquired epileptic aphasia (Landau-Kleffner syndrome Modified ILAE Classification of Epilepsy Syndromes Kwong KL et al .Epidemiology of childhood epilepsy in a cohort of 309 Chinese children. Pediatr Neurol. 2001 Apr

11. Video demonstration of seizures

12. Simple partial seizure with motor signs • may remain strictly focal or epileptic “march” • Speech: • speech arrest • occasionally vocalization • partial dysphasia • Todd’s paralysis

13. Simple partial seizure with somatosensory symptoms • Pins-and-needles, feeling of numbness, proprioception, spatial perception • Visual • Auditory • Olfactory • Gustatory • Vertiginous

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15. Simple partial seizure with psychic symptoms • Dysphasia • Dysmnesic symptoms  • Déjà vu, jamais-vu • Cognitive symptoms  • Affective symptoms  • Illusions • Structured hallucinations

16. Simple partial seizurewith autonomic symptoms • Vomiting • Pallor • Flushing • Sweating • Piloerection • Pupil dilatation • Borborygmi • Incontinence

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18. Complex partial seizures • Primary involvement of only one hemisphere (but often bilateral involvement in the course of seizure) • Impaired consciousness (gradually increasing)

19. Partial Seizures with Secondary Generalization • Onset: Spontaneous • Description of Seizure • Simple partial • Takes his left hand in his right to prevent it from shaking • Turn to the right, left arm starts jerking • Coarse jerking of arms, stretching of back, tonic contraction of face, open mouth • Jerks predominant in left arm and eye, eye blinking, head and eyes to the left

20. Partial Seizures with Secondary Generalization • Secondary generalization • Generalized jerks in face, arms and legs • Left arm bent, right arm stretched • Relaxation and Postictal sleep

21. Absence Seizures • Onset: provoked by hyperventilation • Description of Seizure • Stop hyperventilation • Slight loss of tone in neck muscles • 2 eye blinks about 1 second apart • Regains awareness 1.5 second before paroxysm stops • The duration of impaired consciousness is often shorter than the duration of spike and wave discharge series. It starts later and ends earlier.

22. Absence Seizures with atonic components • Onset: Spontaneous • Description of Seizure • Head drop

23. Atonic Seizure vs Atonic Absence • Atonic Seizure: general loss of tone often resulting in a sudden fall • Atonic Absence: loss of tone is often restricted to the head that gradually goes down

24. Absence Seizure with tonic component • Onset: Spontaneous • Description of Seizure • Upward movement of the eyeballs for 15 seconds • Immediate regain of consciousness

25. Tonic Seizure vs Tonic Absence • Tonic Seizure: tonic seizure affects the whole body resulting in bending forward with abduction of the arms and reddening of the face, sometimes a loss of balance • Tonic Seizure: Head is mainly affected, often with retropulsion of the head and upward deviation of the eyes

26. Myoclonic seizure • Single or multiple, sudden, brief, shock-like jerky contraction • Generalized / face & trunk / one or more extremities / individual muscles or group of muscle • Around hr of going to sleep / awake from sleep • Myoclonic jerks can also be seen in: - spinal cord diseas - dyssynergia cerebellaris myoclonica - subcortical segmental myoclonus

27. Clonic seizure • Tonic seizure with periodic interruptions (shaking) • The diagnosis is rare • When a generalized seizure occasionally lack a tonic component / as a co-existing event in other type of seizure

28. Myoclonic seizure jerky contraction of muscles Regarded as an isolated event Considered as a separate epilepsy type Clonic seizure tonic seizure with periodic interruption (shaking) rarely as a diagnosis usu get involved in other type of seizure (eg. Absence seizure with mild clonic components)

29. Tonic seizure • Rigid, violent muscular contraction, fixing the body & limbs in strained position • Usu deviation of eyes and head • Colour of face distorted: unchangedpaleflushedultimately livid(black & blue; as spasm of respiratory muscle)

30. Tonic-clonic seizure • Most common type of generalized seizure • Also known as ‘grand mal’ • Tonic phase (~10sec): - falls - stridor, cry or moan, cyanosis - incontinence • Clonic phase (~1-2mins): • Postictal phase: - muscles relax - remain unconscious - go into deep sleep

31. Atonic seizure • Sudden reduction in muscle tone • ‘drop attack’ • Prolonged atonic attacks: progressive drop in a rhythmic, successive relaxation manner

32. Epileptic Idiopathic( ~70%) Congenital dysgenesis or malformation Cerebral trauma Space occupying lesion Neurogenerative disorder Syndrome Non-epileptic Infection: fever, meningitis, encephalitis, sepsis Metabolic: acidosis, hypoglycaemia Drugs, toxins Trauma Causes of seizures

33. Approach to a patient with seizure attack • History of present illness • Review of systems • Important relevant aspects • Perinatal • Development • Past medical • Drug • Social • Family • Diet What would you ask in a patient with epilepsy?

34. Physical exam • General • Neurological • Other systems when indicated (e.g. trauma, fever)

35. Investigations of Convulsion • Depends on the clinical presentation and history • CBC • LFT, RFT, blood glucose level, ABG • Infection screen • Toxicology screen • EEG • CT, MRI

36. EEG indicated when epilepsy is suspected CT/MRI Late onset of seizure Partial seizure Interictal neurological signs Progression of seizure despite good complicance

37. Medical Treatment

38. Anti-epileptic drug (AED)

39. Drug complication

40. Principle of medical treatment • Start if seizure becomes recurrent • Monotherapy preferred - decrease drug interaction & toxicity - increase compliance - decrease cost - 50% of children have satisfactory control

41. Treatment- Pharmacological • Aim: fit free • Common agents • Sodium valporate • Phenytoin • Phenobarbitone • Carbamazepine • Most of them have known side effects and monotherapy is preferred for the sake of side effects • Withdrawal of drug therapy can be considered in a patient with no relapse of seizure for 3 or more years; it should be withdrawn slowly

42. Treatment: Diet • Ketogenic Diet • For recalcitrant seizures • Complex myoclonic epilepsy with associated tonic-clonic convulsions • Restricts the quantity of carbohydrate and protein (most calories provided as fat) • Mechanism of action unknown • ? Anticonvulsant effect secondary to elevated levels of beta-hydroxybutyrate and acetoacetate resulting from the ketosis

43. Surgical Treatments • Considered for children with • intractable seizures unresponsive to anticonvulsants • Well-defined focus of epileptogenic activity + identical structural lesion on CT/MRI • Options • Lobectomy and cortical resection • Hemispherectomy • Corpus Callosotomy • Multiple Sub-pial Transection • Vagal nerve stimulation Vagal nerve stimulation

44. Education and support • Good compliance is very important • May disturb the child’s school life • Management during fits • Side effects of the anticonvulsants • Avoid known provoking factors

45. References • Fong GC, Mak W, Cheng TS, Chan KH, Fong JK, Ho SL. A prevalence study of epilepsy in Hong Kong. Hong Kong Med J. 2003 Aug;9(4):252-7. • Kwong KL, Chak WK, Wong SN, So KT.Epidemiology of childhood epilepsy in a cohort of 309 Chinese children. Pediatr Neurol. 2001 Apr;24(4):276-82 • Leung GK, Fan YW, Fong KY. Temporal lobe resection for intractable epilepsy: review of 11 cases. Hong Kong Med J. 1999 Dec;5(4):329-336 • Wong V. Study of seizure and epilepsy in Chinese children in Hong Kong: period prevalence and patterns. J Child Neurol. 2004 Jan;19(1):19-25 • Modified ILAE Classification of Epilepsy Syndromes • Nelson’s Textbook of Pediatrics Ch. 602 • Video Atlas of epileptic seizures - Classical examples, International League against epilepsy

46. Special Thanks to Prof. V. Wong