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A case based introduction to epilepsy. Colin Doherty MD. Seizures and Semantics. Epilepsy: Recurrent unprovoked seizures Prevalence of 1% in population Symptomatic seizures: Single or repeated seizures with a clear proximate cause
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A case based introduction to epilepsy. Colin Doherty MD
Seizures and Semantics • Epilepsy: Recurrent unprovoked seizures • Prevalence of 1% in population • Symptomatic seizures: Single or repeated seizures with a clear proximate cause • Seizure(s) will occur sometime during the life of 10% of the population.
Epilepsy (cont.) • Epilepsy consists of a heterogeneous group of brain disorders.1 • Epilepsy affects individuals regardless of race, age, or gender.2 • Epilepsy costs the nation approximately $12.5 billion annually.2 50$ per head which is about 130 million Euro in Ireland References:1. Mattson. Neurology. 1998;51(suppl 4):S15-S20. 2.Epilepsy: A Report to the Nation. A Review of Epilepsy’s Impact on the Individual and Society at the End of the Millennium. 1999.
Seizures and Epilepsy: Epidemiology • Epilepsy incidence: 50 per 100,000 • Approximately 125,000 new cases each year • Maximal incidence during childhood and after 60 • Epilepsy prevalence: 6 per 1000 (0.6%) • Approximately 1,500,000 active cases in United States and 30-40,000 in ireland.
Recurrence after a First Seizure • 208 Adults (Hauser et al) 1 Year 14% 2 Years 29% 3 Years 34% • 283 Children (Shinnar et al) 1 Year 26% 2 Years 36% 3 Years 40% 4 Years 42%
Classifications • 2 Classification to be aware of. • Seizures (purely descriptive of events) • Epilepsies (ie syndromes describing where and how) • Neither are infallible but generally they are helpful in continutity of care.
Classification of Seizures Commission on Classification and Terminology of the ILAE, 1981
Classification of Epilepsy A Generalized • Primary Generalized Epilepsies - genetic, young, normal brain, good outcome • Childhood Absence • Juvenile Myoclonic Epilepsy (JME) • Absence Status • Generalized epilepsy on awakening • Secondary (Symtomatic) Generalized Epilepsies - Learning difficulty, abnormal brain , life long, diffiicult to control. • Infantile spasms / West’s Syndrome • Lennox Gastaut Syndrome B. Localization related Epilepsies - assume underlying focal abnormality, 20% heritability, difficult to control • Mesial temporal lobe epilepsy - 70% • Temporal neocortical epilepsy • Frontal, parietal and occipital epilepsies
Desired Actions of Antiepileptic Drugs Efficacy No seizures AED No side effects Safety/ tolerability Schachter SC. Epilepsia. 1999;40(suppl 9):S20-S25. Mattson RH. Neurology. 1994;44(suppl 5):S4-S9.
Old drugs (< 1978) Phenytoin Carbamazepine Valproate Ethosuccimide Phenobarbital Primidone New Drugs (>1994) Felbamate Gabapentin Lamotrigine Topiramate Tiagabine Oxcarbazepine Levtiracetam Zonisamide (Vigabatrin) The Armamentarium
AED Selection by Seizure Type Symptomatic Primary Simple & Tonic- Lennox Infantile Tonic- Complex Absence Myoclonic Clonic Gastaut Spasms Clonic Partial CBZ BZ BZ PHT ESM BZ FBM GBP FBM FBM TPM LTG TPM LTG LTG LTG LTG PB TGB TGB PHT TPM TPM TGB VGB TPM VPA
Living With Epilepsy: Report of a Roper Pollof Patients on Quality of Life (n=760) Perspectives of Patients • 59% have difficulty thinking clearly • 51% have limited ability to drive • 44% have limited ability to work • 32% miss days of work or school The Roper Organization Inc. Living With Epilepsy. New York, NY: Roper; 1992.
Case 1 • 45 year-old single man. • Febrile seizures as an infant. • 1st convulsion in his teens. • Typical attacks now very bland, brief aura of deja-vu then confusion rare convulsions. • Current frequency 8-10 per year. • Complains of increasing memory difficulties.
Case report 1(cont’d) • Sticky personality, verbose, very religious. • Nothing else on examination. • Has been on all major classes of anti-epileptic drugs in the last 20 years but with little effect on seizure control. • Patient is getting depressed with loss of psychosocial independence. • What would you do now?
Case 1 - 45 year old man CPS video
Left- sided leads Left- sided leads Left- sided leads RK Seizure onset
Left- sided leads Left- sided leads RK seizure spread
Dx: Mesial Temporal Sclerosis Rule of 70s 70% of TLE 70% of Partial Epilepsy 70% uncontrolled 70% seizure free after surgical removal
Case 2:16 y.o. boy with long-standing learning disability. • GTCS at 5pm lasting 17 minutes. Given rectal diazepam. Now post-ictal. • Seizure begins again at home. Seizing for 5 minutes before you arrive. • PHX of Lennox-Gastaut syndrome. • On PTH, CBZ, LTG and VPA. • 0/E. Grossly obese. Unconscious, only eye twitching.
Facial Angiofibromas, Hypomelanotic Macules Peri-ungal fibromas
Diagnosis? • Tuberous Sclerosis complex • A genetic disorder that causes benign tumors to grow in all major organ systems, including the brain, skin, heart, kidney, lung, and eye. • Most significant manifestations clinically are epilepsy and learning disability caused by CNS abnormalities. • 2 genes identified, TSC1 on Chr 9 and TSC 2 on Chr 16. • Cortical Tubers are highly epileptogenic and can cause severe refractory epilepsy with status.
Treatment of prolonged seizures Based on this retrospective study, the treatment of SE is remarkable for both inadequacy and ineffectiveness. The inappropriate use of therapeutic regimens in the management of SE may be seen as an important cause of ineffective medical treatment. Cascino et al, Mayo Clinic Proc 2001; 76:39-41 Treatment of SE in Richester, Minn 1965-84.
Treatment Guidelines • There are few therapeutic options more important in the treatment of potentially damaging PROLONGED SEIZURES of ANY TYPE than the TIMELY use of BENZODIAZEPINES. • San Francisco pre-hospital study. - Aldredge et al NEJM 2001; 345:631-37.
Options • General precautions (protect head - recovery position, observation) - NB epileptic patients do not swallow their tongues!!!!!!!!!! • Rectal Diazepam 10mg (after 5mins of seizures) • Buccal Midazolam 10mg (newly available) • I/M midazolam (not diazepam) • ‘A little of what you lack helps a lot’- administer missed drug by NG. • I/M fosphenytoin (not available yet). • IV lorezepam or diazepam - paramedics?
Case report 3 • 45 year-old carpenter. • 20 year h/o clinical events: • brief • highly stereotyped semiology • nocturnalnocturnal and diurnal, frequency • ?entire preservation of the awareness • no postictal confusion, dysphasia or headache
Case report • Neurologic exam: Normal • Normal MRI brain • Normal EEG • video EEG : Normal background, no interictal activity, 4 stereotyped typical events( 2 nocturnal, 2 diurnal)
JD: Event Onset EEG normal until obscured by movement artifact…no epileptic activity visible!
Video Frontal Lobe Seizure video
NREM sleep disorders REM sleep disorders Rhythmic movement disorder Pseudoseizures Tics Nocturnal panic attacks Psychogenic dissociative states Post-traumatic stress disorder Differential Diagnosis 1
Your problem • Discharged back to your care. • Increasingly frequent seizures • No effect of any medications • What do you do now?
Differential Diagnosis 2 Frontal Lobe Seizures
Problem 2 : Signal to noise 3 Tesla 1.5 Tesla
Dysplastic cortical lesions- highly epileptogenic • Intrinsic epileptogenicity of human dysplastic cortex as suggested by cortiocography and surgical results- Palmini A @ co, Porto Alegre Epilepsy Surgery Program, Hospital Sao Lucas da PUCRS, Brazil ( Ann Neurol, April 1995) • Electroencephalographic characterization of an adult rat model of radiation-induced cortical dysplasia-Kondo S @co, Section of Epilepsy, Department of Neurology, The Cleveland Clinic Foundation, Cleveland, Ohio ( Epilepsia, Oct 2001)
Case 4 • 30 year-old woman • Juvenile Myoclonic epilepsy • Well controlled on Valproate Chrono 600mg BD • Wants to get pregnant • What would you do?