epilepsysymposium 2023.ppt

INTRODUCTION TO THE EPILEPSY SYMPOSIUM O R M U A E R N A T A I N L A U J LT . U R D NS CO LO IS G T WHAT IS EPILEPSY? epilepsy is defined as recurring, unprovoked (spontaneous) seizures (1 in 100-200 people) acute symptomatic seizures are provoked by acute insults such as stroke, infection, al...

INTRODUCTION TO THE EPILEPSY SYMPOSIUM O R M U A E R N A T A I N L A U J LT . U R D NS CO LO IS G T WHAT IS EPILEPSY? epilepsy is defined as recurring, unprovoked (spontaneous) seizures (1 in 100-200 people) acute symptomatic seizures are provoked by acute insults such as stroke, infection, alcohol withdrawal, or a metabolic disturbance (1 in 20 people) SEIZURE TYPES primary generalized onset - electrical discharges appear to start over the whole brain at the same time on EEG partial/focal onset - electrical discharge appears to start in one cortical region and then may remain localized or may spread over the whole brain - secondary generalized CLASSIFICATION OF SEIZURES Idiopathic (Primary) Generalized Seizures       limited repertoire of seizures tonic-clonic seizures (“grand mal”) absences (“petit mal”) tonic seizures atonic seizures myoclonic seizures IDIOPATHIC GENERALIZED SEIZURES onset in childhood or adolescence usually no focal symptoms/signs often a number of seizure types cluster a polygenic cause is presumed with no identifiable structural lesion on imaging generalized (all leads) spike and wave discharges on EEG may be induced by hyperventilation, and on photosensitivity testing provoked by sleep deprivation JUVENILE MYOCLONIC EPILEPSY (JME) commonest form of primary generalized epilepsy 3-12% all epilepsy juvenile onset, probably lifelong early morning myoclonic jerks (ask) photosensitive, sleep deprivation triggers +/- absences generalized tonic clonic seizures – occur without warning although may be preceded by a cluster of myoclonic jerks EEG APPEARANCE OF A MYOCLONIC JERK LASTS APPROXIMATELY ONE SECOND IN FULL CONSCIOUSNESS GENERALIZED TONIC CLONIC SEIZURES “GRAND MAL” occurs with sudden onset, without warning in primary generalized epilepsy –increased risk of injury for patient tonic phase  continuous muscle spasm, fall, cyanosis, tongue biting, incontinence clonic phase  rhythmic jerking slows and gets larger in amplitude as attack  ends; the duration is typically 1-3 minutes post-ictal (post-seizure) phase  coma, drowsiness, confusion, headache  muscle aching all over  red/blue, wakes in ambulance/or A&E ABSENCES - “PETIT MAL” abrupt short, 5-20 seconds multiple times/day, can lead to learning difficulties unresponsive, amnesia for the gap, rapid recovery tone preserved (or mildly reduced) if absences only, tend to remit in adulthood (childhood absence epilepsy) ABSENCES ARE CHARACTERIZED BY 3HZ SPIKE & WAVE ON EEG PARTIAL SEIZURES = FOCAL ONSET SEIZURES simple partial seizure – patient aware = an aura now called focal seizure with awareness complex partial seizure – aura/warning with a level of reduced awareness now called focal seizure with impaired awareness (patients may call these “absences”, “blanks” – this is medically inaccurate terminology) can be secondary generalized- patient may first experience a prior warning with or without reduced awareness before secondarily developing a tonic clonic seizure SEIZURE ACTIVITY LOCALIZED AT ONSET RECRUITS ACTIVITY IN OTHER LEADS AS THE SEIZURE SPREADS PARTIAL SEIZURES-FREQUENCY BY LOBE Parietal 1% Occipital 4% Frontal 25% Temporal 70% TEMPORAL LOBE SEIZURES BY AETIOLOGY Post Traumatic 8% Other 4% Vascular 10% Hippocampal sclerosis 50% Birth Hypoxia 10% Tumour 18% Risk Factors for Later Epilepsy 7%– Febrile Convulsions Febrile convulsion <6 months – 40% patients hippocamapal sclerosis have a history of febrile convulsion Duration >15 minutes; recurrence within 24 hours Focal features; post seizure weakness = Todds paresis. Epilepsy Surgery. TEMPORAL LOBE EPILEPSY SYMPTOMS AND SIGNS  hallucinations of taste, speech and /or smell, visual distortion; memory déjà vu and jamais vu  epigastric rising sensation (over humpback bridge)  fear, elation, low mood  pallor / flushing / heart rate changes (can mimic panic/hyperventilation attacks)  manual automatisms- semi-purposeful hand movements  oral automatisms- lip smacking, chewing movements  dystonic posturing (limb rises)  speech disturbance (dominant  hemisphere onset)  last 1-3 minutes typically FRONTAL LOBE SEIZURES brief 10-30 seconds rapid recovery, frequent predominantly nocturnal  forced head /eye deviation to contralateral side  motor activity often bizarre, thrashing  often misdiagnosed as non-epileptic  ictal EEG (during the seizure) is often normal  Jacksonian spread with Todd’s paresis  automatisms, dystonic posturing for example  a fencing posture (overlap TLE) JACKSONIAN MARCH – POSITIVE MOTOR OR SENSORY SYMPTOMS +/- TODDS PARESIS (POST SEIZURE WEAKNESS) STRONGLY ASSOCIATED WITH A SPACE OCCUPYING LESION PARIETAL/OCCIPITAL LOBE EPILEPSY SYMPTOMS parietal  positive sensory symptoms (unlike TIA/stroke)  tingling, pain  distortion of body shape/image  Jacksonian march of positive sensory symptoms occipital  typically simple visual hallucinations -balls of coloured or flashing lights  amaurosis (blackout or whiteout) at onset -25% VIDEO EEG TELEMETRYWHAT TYPE OF SEIZURE IS THIS? SEIZURES ARE SEIZURES AREN’T THEY? some anti-epileptic drugs make myoclonic jerks and absences worse phenytoin*, carbamazepine, gabapentin, pregabalin (*although phenytoin treats tonic clonic seizures so safe to use in status epilepticus) some syndromes remit (childhood absences), and some don’t (juvenile myoclonic epilepsy) or epileptogenic lesion may be present (stroke, vascular lesion, tumour, injury/ scar); accurate diagnosis allows accurate advice to patient regarding medication TO WHOM ARE YOU GOING RECOMMEND A BRAIN SCAN? patients with a new onset of absence seizures? Jacksonian motor or sensory seizures? patients who develop a Todds paresis (unilateral weakness) ? seizures suggestive of juvenile myoclonic epilepsy? alcohol withdrawal seizure? ANSWER Jacksonian motor or sensory seizures Patients with focal neurological deficit (including a temporary unilateral Todds paresis) Alcohol withdrawal seizure; only scan if subdural haematoma suspected fall, hit head, found on the floor, bruising on head SUMMARY A knowledge of seizure types allows accurate diagnosis and directly influences ongoing investigation choices EEG for primary generalized epilepsy MRI brain scan +/- EEG for focal onset seizures And patient management – treatment and prognosis. PREVIOUSLY USED QUESTIONS INTRODUCTION What is the difference between provoked seizures versus epilepsy? Give some causes of both Idiopathic (primary) generalised epilepsy versus focal onset epilepsy. What are the diagnostic and clinic features of each? Describe the clinical features of temporal lobe versus frontal lobe seizures In a patient with a new onset of a seizure(s) when would an urgent (in-patient) brain scan be indicated and why? Questions on pharmacology • What are the ideal properties of an antiepileptic drug? • What are the outstanding problems with all antiepileptic agents? • Why do antiepileptic agents have so many side effects? • What issues particularly face women starting epilepsy treatment? QUESTIONS - PATIENT What did the patient teach you that you didn't know before/from the lectures? What kind of epilepsy does the patient have and why? What advice is needed for young women with epilepsy? What areas of life are affected by having epileptic seizures?