Epilepsy Syndromes and Disorders with Pathognomonic EEG Patterns PDF

Epilepsy Syndromes and Epilepsy Disorders with Pathognomonic EEG Patterns Heather Ravvin McKee, MD Associate Professor of Neurology University of Cincinnati Gardner Neuroscience Institute Ohio NeuroDiagnostic Society (ONDS) Annual Confer...

Epilepsy Syndromes and Epilepsy Disorders with Pathognomonic EEG Patterns Heather Ravvin McKee, MD Associate Professor of Neurology University of Cincinnati Gardner Neuroscience Institute Ohio NeuroDiagnostic Society (ONDS) Annual Conference June 24, 2023 Disclosures none Objectives Define epilepsy syndromes Discuss epilepsy syndromes from pediatric through adulthood Define epilepsy disorders with pathognomonic EEG patterns Discuss epilepsy disorders with pathognomonic EEG patterns What are epilepsy syndromes? Syndrome: group of signs or symptoms that happen together and help identify a unique medical condition Epilepsy Syndrome: can share specific signs or symptoms – Type of seizure(s) they have – Age when seizures start – Pattern on EEG Epilepsy Syndromes Symptomatic/Encephalopathic Progressive and Infantile Myoclonic Epilepsies Focal Idiopathic Febrile Seizure Epilepsy Syndromes Symptomatic/Encephalopathic Progressive and Infantile Myoclonic Epilepsies Focal Idiopathic Febrile Seizure Infantile Spasms and West Syndrome Infantile spams Infantile – Flexor, extensor, lightning, or nods—most are mixed Spasms – Onset 4-8 months, peak 5 mo West Syndrome – Triad→ – Onset 4-7 months, always before 1 year old Hypsarrhythmia Developmental Delay – Boys>Girls Intellectual disability 75-90% Etiology and Differential Dx Symptomatic, 75-85% – Underlying conditions Genetic Metabolic Congenital infection Neonatal infection Asymptomatic Differential Diagnosis: benign myoclonus, benign myoclonic epilepsy, GERD Treatment and Prognosis Steroids –ACTH or prednisolone Vigabatrin (tuberous sclerosis) Ketogenic Diet Zonisamide Vitamin B6? Prognosis partly based on early treatment, but typically poor Lennox-Gastaut Syndrome Multiple seizures types (TONIC) Triad: Cognitive dysfunction Slow GSW: 1.5-2 Hz, multifocal epis, gen fast activity  Ictal Post-ictal Clinical syndrome Onset 1-8 years, typically 3-5 yr 10-25% cases are preceded by infantile spasms Causes – Structural/metabolic 70-78% Meningoencephalitis Cortical dysplasia Hypoxia TBI – Unknown Family history of epilepsy in 3-30% Overall refractory to ASDs and poor prognosis Cannabidiol…. Dravet Syndrome Severe Myoclonic Epilepsy of Infancy (SMEI) Prolonged FS in the 1st year of life Seizure-free period followed by myoclonic seizures at 1-4 yr old Normal early development, then later deterioration – Pyramidal signs and ataxia EEG: slow SW, polyspike-and-wave 70-80% mutation in SCN1A – Genetic testing is indicated Treatment Sodium-channel medications may WORSEN seizures – Avoid CBZ, OXC, lamotrigine, etc Worse seizures with heat, may need to avoid environmental stimuli Cannabidiol…. Myoclonic Astatic Epilepsy (MAE) or Myoclonic Atonic Epilepsy or Doose Syndrome Type of Generalized Epilepsy Onset 1-5 years old EEG: 2-3 Hz gen SW, polyspike and 4-7 Hz central/vertex rhythmic theta activity MRI: normal Associated with SCN1A mutation (and 5% have GLUT-1 deficiency) Boys>girls (2:1) 84% have normal development prior to seizures, others have delay primarily with speech Prognosis: typically poor with severe intellectual disability, ataxia, poor motor function, dysarthria, poor language development Doose Syndrome EEG Epileptic Encephalopathy with Continuous Spike and Wave During Sleep (CSWS) or Electrical Status Epilepticus in Sleep (ESES) Epileptiform activity occupying >85% of NREM sleep 2 Syndromes – Landau-Kleffner Syndrome (LKS) – Continuous Spike and Wave during Sleep (CSWS) Landau-Kleffner Syndrome Typically age 3-10 y Sudden or gradual aphasia Verbal auditory agnosia (inability to comprehend speech) 2/3rd have seizures ADHD MRI: typically normal (but PET and SPECT typically abnormal) CSWS Global regression in cognition and behavior Majority of patients have seizures May have identifiable pathology: neuronal migrational disorder, polymicrogyria, shunted hydrocephalus, porencephaly, thalamic lesions 10-15% have a family history of epilepsy Treatment: medications, immune modulatory therapy (steroids, IVIG), and surgery Epilepsy Syndromes Symptomatic/Encephalopathic Progressive and Infantile Myoclonic Epilepsies Focal Idiopathic Febrile Seizure Panayiotopolous Syndrome (Early Childhood Onset “Occipital” Epilepsy) Seizures: behavioral agitation, headache, autonomic symptoms, and motor (hemi-clonic or GTC)—prolonged and nocturnal (2/3) – Autonomic symptoms: vomiting, pallor, cyanosis Peak onset 3-6 years old Interictal EEG: occipital spikes in sleep (classic) 85% have Boys Frequent absence seizures (pyknolepsy) Hyperventilation induces absence seizures Types: typical and atypical Typically resolves in 2 years (60%) Cognitive deficits Long-term psychosocial problems OCD ADHD Absence Pathophysiology and Treatment Not fully understood Abnormal oscillatory rhythms are believed to develop in thalamocortical pathways Ethosuxamide, Lamotrigine, Valproic Acid (Depakote) Double-blinded RCT compared the 3 and found Ethosuxamide provides the best combo of seizure control and fewest attentional side effects; therefore, it is optimal initial therapy Juvenile Absence Epilepsy Onset 10-17 years old Less frequent absence seizures (one to a few per day) More associated with GTCs (80%) Less severe impairment in consciousness Juvenile Myoclonic Epilepsy Onset 12-18 years old Seizures upon awakening in AM or after nap Triggers: sleep deprivation, stress, fatigue, and alcohol Myoclonic, GTC (85-95%), and clonic-tonic-clonic, absence (18-38%) EEG: – Interictal high amplitude, generalized 4-6 Hz polyspike and wave – 30% have photosensitivity 40-50% with family history – Likely polygenic inheritance (but AD and AR exist too) Treatment: VPA, LTG, TPX, LEV, ZNS, BRIV, (Lacosamide, Perampanel, Clobazam) Prognosis: typically GOOD! Normal photic driving Genetic Epilepsy and Febrile Seizures Plus, GEFS+ FS after 6 yr old OR occurrence of other seizure types Almost any type of seizure can occur Associated mutations SCN1A, SCN1B, GABRG2 But mutations are only found in 10-20%, so genetic testing is not advised Epilepsy Syndromes Symptomatic/Encephalopathic Progressive and Infantile Myoclonic Epilepsies Focal Idiopathic Febrile Seizure Febrile Seizures Onset between 1-5 years old (typically 12-30 mo) GTCs are most common No intracranial infection or defined cause 3-5% of general population 10-20% of siblings also have febrile seizures Recurrence risk: – 33% will have a second FS – ½ of those will have a 3rd FS – 50% recur in the first 6 months, 75-90% in the 1st year Epilepsy Disorders with Pathognomonic EEG Patterns These are disorders that are often associated with specific EEG patterns They are not epilepsy syndromes Finding the EEG pattern can help make the diagnosis Pathognomonic: of a sign or symptom, specifically characteristic or indicative of a particular disease or condition Pathognomonic EEG pattern types Periodic – CJD – SSPE – Herpes Encephalitis Rhythmic – Anti-NMDA Receptor Encephalitis Other – Angelman Syndrome Crutzfeldt-Jakob Disease (CJD) Rapidly progressive, invariably fatal neurodegenerative disorder felt to be caused by an abnormal isoform of a cellular glycoprotein known as the prion protein EEG: Generalized periodic discharges typically develop in the first 3 months of the disease The periodic pattern is not always seen Stimuli can evoke the periodic discharges The complexes usually have bilateral or generalized distribution and occur at around 1 Hz frequency (0.5-2 Hz range) Myoclonic jerks are typically present when the discharges develop, and they may or may not be time locked to the complexes Variations do occur CJD Subacute Sclerosing Panencephalitis (SSPE) A progressive neurological disorder characterized by inflammation of the brain (encephalitis). The disease may develop due to reactivation of the measles virus or an inappropriate immune response to the measles virus. EEG: generalized periodic discharges of longer interval than CJD Bilaterally synchronous, high-amplitude spike or slow-wave bursts that often correlate with clinical myoclonus As SSPE progresses, the background activity becomes suppressed, resulting in a burst-suppression pattern SSPE Herpes Encephalitis Herpes simplex encephalitis (HSE) is a rare neurological disorder characterized by inflammation of the brain (encephalitis). Herpes simplex encephalitis is caused by a virus known as herpes simplex virus (HSV). There is typically no rash or skin changes. It often presents with altered mental status, seizures, headaches, and signs of meningitis EEG: lateralized periodic epileptiform discharges (LPDs), bihemspheric independent discharges are sometimes seen (BiPDs) Lateralized periodic discharges (LPDs) The discharge may be simple or complex Ictal-interictal continuum, but if clinical or have evolution are considered ictal They are not specific for a certain diagnosis – Most often a result of an acute structure lesion: stroke, acute infection, or rapidly growing brain tumor (GBM) – Can also occur with acute metabolic disturbance, particularly when the patient has a chronic structure lesion – Can occur with chronic epilepsy Anti-NMDA Receptor Encephalitis Type of autoimmune encephalitis Associated with antibodies to neuronal cell surface/synaptic proteins Often associated with ovarian teratoma Clinical features: may start with a prodrome of a viral-like process, prominent psychiatric manifestations, sleep disorder, memory problems, seizures, altered mentation with reduced awareness, dyskinesia, autonomic instability, language abnormalities EEG: extreme delta brush (often seen with more prolonged illness), specificity of this pattern is unclear, but raises consideration of this syndrome Treatment consists of immunosuppression and tumor resection when indicated Extreme Delta Brush Angelman Syndrome Neurodevelopmental disorder characterized by severe intellectual disability, postnatal microcephaly, and a movement or balance disorder, usually in the form of gait ataxia and/or tremulous movement of limbs Small interstitial deletion between 15q11 and 15q13, maternally derived EEG: notched delta Notched Delta associated with AS Conclusions Epilepsy syndrome: defined by seizure types, age at onset, EEG pattern Pathognomonic EEG: defined EEG patterns in certain neurologic conditions  Thank you! Heather Ravvin McKee, MD [email protected] Without good EEG techs, we don’t have good EEG!