EEG BOARD EXAM 2023 with verified questions and answers

SSS/BETS (small sharp waves / benign epileptiform transients of sleep) Low voltage, short duration, diphasic spikes with a steep descending limb. Usually seen in drowsiness and light sleep. SREDA (subclinical rhythmic electrographic discharges of adults) Sharply contoured theta activity in the posterior head region. A normal variant in older adults during wakefullness. 14 and 6 positive spikes 1-2 seconds of sharply contoured discharges in the posterior head regions in light sleep. Presents in adolescents. 6 hz spike and wave Midparietal low amplitude discharges. Occurs in young adults in drowsiness and disappears in sleep. My rhythm Oscillating 10 hz waves seen in leads overylying the senserimotor cortex in the absence of movement. If a patient moves or thinks about moving their contralateral limb, this rhythm will be suppressed. Wickets Symmetric monophasic sharp wave occuring predominantly in older adults during light sleep in temporal leads without disruption of the background. 3 hz slow wave activity 3 hz waves without an associated spike which can be seen during hyperventilation in childhood RTTBD (rhythmic temporal theta bursts of drowsiness) 5-6 hz rhythmic waves in the temporal lobe. Seen in young adults during drowsiness. Breach rhythm Unilateral high voltage iregular wave rhythms due to alteration of conductance commonly seen in patients with a skull defect. Anterior eye blinks (bells phenomenon) Positive downward deflection, maximal in the frontopolar leads, followed by a negative deflection from eye opening. Disappears in sleep. EKG Rhythmic electropositive discharges in one or multiple leads, most often in the occipital leads. Time locked and synchronous with the EKG tracing. Pulse Rhythmic slow waves in a single lead due to a close pulsating vessel. Time locked but delayed after each QRS sample. Lateral eye movements Very slow out of phase derivations involving anterior electrodes due to movement of the positively charged cornea. Best appreciated in drowsiness and early sleep when patient experience rolling eye movements. Muscle Extremely high frequency waves often generated from the frontalis and temporalis muscles. Usually spares central leads. Disappears in sleep. Glossokinetic Diffuse, low frequency discharges produced by movements of the negative tip of the tongue. Can be induced by saying "la la la la", chewing, or sucking. Electrode pop Single or multiple sharp waves localized to a single electrode without a surrounding field. Disappears by reapplying an electrode. GRDA (generalized rhythmic delta activity) Generalized in all leads, typically signifies global cerebral dysfunction, such as in a severe encephalopathy, but is not to be a risk factor for seizure or seizure tendency. Frontally dominant GRDA Can be seen with a variety of pathologies including posterior fossa lesions, intracranial lesions, and increased intraventricular pressure. LRDA (lateralized rhythmic delta) Can be seen with focal lesions such a hemorrhage, tumor, or stroke. Is associated with increased seizure risk/seizure tendency. LPDs (Lateralized periodic discharges) Often seen with focal acute or subacute cerebral dysfunction, such as with herpes simplex enchephalitis, stroke, abscess, or subdural hematoma. GPDs (Generalized periodic discharges) Felt to have highest seizure tendency of the 'ictal-interictal' patterns. If seen clinically with rapidly progressive dementia it can be strongly suggestive of Creutzfeldt-Jakob Disease. End stage liver disease This disease can present with hyperammonemia and generalized periodic waves with triphasic morphology. They are bilaterally synchronous and usually frontally predominant and exhibit three phases (i.e. negative, positive, negative). Triphasic waves can also be seen in ESRD and other forms of metabolic encephalopathy. Subdural Hematoma Hemispheric asymmetry with the lower amplitude discharges localizing to the affected hemisphere. HSV Encephalitis Due to the predilection for the temporal lobes, patients will present with lateralized periodic discharges (LPDs) most prominent in temporal leads. Stroke Shows focal irregular theta/delta activity with LRDA or LPDs. Creuztfeldt-Jakob Disease (CJD) Generalized periodic discharges, spikes, and spike-waves with a disorganized background. Fatal familial insomnia (FFI) Loss of sleep spindles. Subacute sclerosing panencephalitis periodic high-amplitude complexes with high-amplitude bisynchronous delta waves, frontal rhythmic delta activity, generalized periodic discharges, electrodecremental periods following EEG complexes, and focal spike and slow-waves. Tay-Sachs disease Slow background with or without multifocal epileptiform discharges. Alzheimer's disease (AD) Slow background with or without multifocal epileptiform discharges. Angelman Syndrome Notched delta activity. Lithium toxicity Generalized delta/theta activity with multifocal spikes. Hypoxic ischemic encephalopathy Can present secondary to cardiac arrest, drug overdose, drowning, etc. EEG can have a variable pattern. Poor prognostic EEG findings include: burst suppression, monorhythmic patterns, alpha coma (unless in the setting of reversible cause for coma such as metabolic dysfunction, sedative drugs, etc.), generalized periodic discharges, and electrocerebral inactivity (ECI). brain death Criteria for WHAT include the use of at least 8 scalp electrodes, 10 cm interelectrode distances, normothermia, and electrocerebral silence, and sensitivity of least 2 microvolts per millimeter for at least 30 minutes. Focal onset seizures Previously called partial seizures, focal onset seizures can be subclassified as focal aware or focal with impaired awareness. Focal aware seizure Patient is aware of the ictal symptoms during focal seizure activity. This is often seen with frontal, parietal and lateral or non-dominant temporal seizures. An example is a patient who can report a "Jacksonian march" seizure semiology which can be more formally identified as a focal motor aware seizure. Focal seizure with impaired awareness Self-awareness is not maintained with focal seizure activity, often due to involvement of the hippocampus. An example is a patient that is temporal lobe seizure with associated semiology of starring and unresponsiveness. Formally called complex partial seizures. Motor onset Automatisms, clonic, hyperkinetic, etc. Non motor onset Behavior arrest, sensory, emotional, etc. Temporal lobe seizure Can present with an aura of unusual smell, taste, automatisms (lip smacking, hand rubbing), or feeling of deja vu. The most common focal epilepsy. Parietal lobe seizure Can present with hemibody parasthesias. Frontal lobe sieuzre Diverse, but often involves hyperkinetic or bilateral atypical movements, such as clapping and leg bicycling. These may be brief and sudden, arise from sleep and have minimal post-ictal confusion. Focal seizure to bilateral tonic clonic Presents with a focal onset of symptoms with progression to involve the whole cortex and bilateral tonic clonic acitivity. Use to be called partial seizure with secondarily generalization. Generalized onset seizure Presents with acute onset of ictal activity involving the whole cortex. Generalized What type of seizure types are these? Absence, myoclonic, tonic clonic, and infantile spasms. Electrodecrement Usually after a generalized tonic clonic seizure, the EEG will show a generalized low amplitude record with irregular slowing known as WHAT? Hypoxic-ischemic injury Cardiac Arrest, Hypotension, Hypovolemia, Drowning, Hanging Electrolyte/metabolic Hypo/Hypernatremia, Hypoglycemia, Non-ketotic hyperglycemia, Uremia, Hyperthyroidism, Porphyria. Traumatic Brain Injury (TBI) Blunt or penetrating trauma, Motor vehicle accident, Fall. Drug Toxicity Cocaine, PCP, Alcohol, Opiods (Tramadol, Mepheridine), Amphetamines. Drug Withdrawal Bupropion, Tramadol, Alcohol. Infection (Encephalitis/Meningitis/Cerebral Abscess) Viral (especially HSV), Bacterial, Parasitic. Neurovascular Injury Ischemic stroke, subarachnoid hemorrhage, Intraparenchymal hemorrhage (lobar). Other Eclampsia, PRES, Febrile illness. Epilepsy Criteria At two unprovoked seizures occurring more than 24 hours apart. One unprovoked seizure and the probability of a further seizures deemed by the practitioner is higher than 60%. Diagnosis of an epilepsy syndrome. Genetic This typical represents generalized epilepsy syndromes (absence epilepsy, juvenile myoclonic epilepsy (JME), Doose syndrome, etc.). Structural Mesial temporal sclerosis, focal cortical dysplasia, heterotopia, and acquired brain injuries (stroke, trauma). Metabolic Mitochondrial disorders, glucose transporter (GLUT-1) deficiency, and peroxisomal disorders. Presents predominantly in the neonatal or infancy period. Immune Rasmussen encephalitis, NMDA receptor encephalitis, etc. Infectious Viral encephalitis/meningitis, toxoplasma gondii, neurocysticercosis, cerebral malaria, etc. Unknown Formally known as cryptogenic, this title is reversed for those with no clear etiology. Benign familial neonatal convulsions An autosomal dominant disorder which presents usually around the 4th-6th day of life with focal and sometimes generalized clonic seizures in otherwise healthy infants. Seizures are frequently self-limiting and resolve without intervention after a few days. There is a strong association with potassium channel defects (KCNQ2 or KCNQ3 gene mutations) but there is also non-familial sporadic forms (benign neonatal convulsions). Formally called "5th day fits" Myoclonic epilepsy of infancy Presents within the first 3 months of life with focal myoclonic seizures, focal motor seizures and tonic spasms. EEG shows polyspike and waves with myoclonic jerks. Interictal EEG can be normal but can have a burst suppression pattern, particularly during sleep. May have "reflex seizures" triggered by startling noise or tactile stimulation. Reflex variant is a good prognostic sign, suggesting a truly "benign" course without cognitive impairment. Valproic acid is valuable in the management of the myoclonic activity. Ohtahara syndrome / Early infantile epileptic encephalopathy (EIEE) Presents usually within the first 3 months of initially with tonic spasms, focal/partial seizures, and generalized tonic-clonic seizures. Develops in patients with secondary brain insults such as brain malformations, metabolic syndromes (nonketotic hyperglycinemia, pyridoxine dependency, carnitine palmitoyltransferase), and mitochondrial disorders. EEG will show an erratic burst suppression with burst of high voltage spikes/polyspikes. Prognosis is poor with reduced life expectancy; Patient often die during infancy. Aicardia syndrome This X-linked dominant disease presents usually in the first three months of life but can be later in the first year of life. Presents with the typical triad of agenesis of the corpus callosum, chorioretinal lacunae, and infantile spasms. West syndrome Presents in the first year of life (3-7 months) with (1) infantile spasms; brief episodes of axial flexion in clusters (spasms) which has an electrodecrement during the events if captured on EEG, (2) developmental delay, and (3) hypsarrhythmia. Hypsarrhythmia describes the interictal EEG of those with West syndrome; chaotic high-amplitude, arrhythmic delta activity with independent multifocal spike discharges. Sometimes West syndrome is simply called "infantile spasms" which actually only refers to the epileptic seizures seen with the disease. Can be cryptogenic or be secondary to a wide rage of diseases: Tuberous sclerosis, hypoxic-ischemic injury, Down syndrome, developmental brain malformations, Menkes disease, Metabolic/Endocrine disorders (maple syrup urine disease, and phenylketonuria, mitochondrial disorders. Both Ohtahara syndrome and Myoclonic epilepsy of infancy can develop this syndrome with age. Patients are poorly responsive to therapies and many go on to develop Lennox-Gastuat syndrome. Treatment: ACTH, glucocorticoids. Vigabatrin should be used if spasms are associated with tuberous sclerosis. Dravet syndrome (severe myoclonic epilepsy of infancy, SMEI) This syndrome is a medically refractory epilepsy which presents within the first year of life with febrile seizures, myoclonic seizures, focal seizures and generalized convulsive seizures. Associated with SCN1A gene mutations. This syndrome carries a grim prognosis, and a high frequency of sudden unexpected death in epilepsy (SUDEP). Treatment: Stiripentol, clobazam, vaproic acid and cannabidiol. Febrile Seizures Presents between 6 month to 6 years of life in association with fever, without CNS infection or history of afebrile seizures/epilepsy. While 3% of children under 6 years of age have febrile seizures, only a small percentage of these patients develop epilepsy (<5%). AEDs are often not required Genetic epilepsy with febrile seizures plus (GEFS+) Formally known as generalized epilepsy with febrile seizures plus. Patients present with recurrent febrile seizures beyond 6 years of age. Patients will also have afebrile generalized seizures (generalized tonic-clonic, myoclonic, absence, and/or atonic). Associated with an autosomal dominant mutation in the SCN1A or SNC1B gene which encodes sodium channel subunits. Lennox Gastaut syndrome Presents in the first 3-5 years of life with developmental delay and multiple seizure types such as tonic, atypical absence, and atonic. Occurs secondary to a wide range of etiologies. Interictal EEG will show generalized slow (1.5 Hz to 2.5 Hz) spike-and-wave activity with increased disorganization during sleep. Generalized paroxysmal fast activity (GPFA) can also be seen on interictal EEG. Tends to be refractory to treatment. Panayiotopoulos syndrome Presents in childhood (2-8 years) with vomiting, migraine features, autonomic symptoms, and acute loss of tone (ictal syncope) due to focal occipital lobe seizures. Interictal EEG will show bilateral independent occipital spikes. Most cases spontaneously resolve within a couple years of disease onset while some evolve into having BECTS. Benign rolandic epilepsy with centrotemporal spikes (BECTS) The most common pediatric syndrome. 25% of cases have a family history with an autosomal dominant pattern of inheritance. Chromosome 15q14 (alpha-7 subunit of Ach receptor) abnormalities are seen in some familial cases. Presents between 7-13 years of life with symptoms of hemifacial twitching, excessive salivation, and inability to speak from sleep due to focal seizures in the rolandic region. Occasionally these seizures can generalize. Electroencephalography will show bilateral independent centrotemporal (i.e. "Rolandic" fissure) spikes during light sleep. Patients often outgrow the disorder by 14-16 years of age. Treatment with AEDs should be reserved only for patients with very frequent seizures and/or daytime events. Doose Syndrome / Myoclonic-atonic epilepsy A primary generalized idiopathic disorder which presents in early childhood (2-5 years) in boys > girls. Presents with multiple seizure types including myoclonic, astatic/atonic, and absence. Children often develop normally before the onset of seizures, then ~33% of patients decline to a moderate-severe intellectual disability. EEG will initially be normal and will progress to brief bursts of 2-5 Hz spike and wave discharges. Landau Kleffner Syndrome Also called acquired epileptic aphasia. Onset between 2-12 years with a male predominance. Patients are developmentally normal prior to disease onset which includes language regression and various seizure types. First symptoms are usually an auditory agnosia (i.e. inability to recognize or differentiate between different words). EEG will show near-continuous, diffuse sleep-activated spikes, also called continuous spike and waves during slow sleep (CSWS). Eventually over time the EEG pattern will evolve to electrical status epilepticus during slow sleep (ESES). Absence Epilepsy Presents between 5-15 years of life with staring spells of brief duration and lack of aura or postictal state. These seizures are associated with a thalamic ictal onset and can be triggered by hyperventilation. Patients often present to seek medical care after family/teachers note "daydreaming" episodes or declining school performance. EEG will show 3 Hz spike-and-wave discharges during the absence seizure and an otherwise normal EEG background. Treatment: Ethosuximide (T-type calcium channel blocker), or valproate. These seizures can be worsened by sodium channel drugs (phenytoin and carbamazepine). Associated with gamma 2 subunit of the GABA receptor genes (GABRG2, GABRG3, GABRA1), as well as caclium (CACNA1A) and chloride channel genes (CLCN2). Familial nocturnal frontal lobe epilepsy (ADNFLE) Most begin in childhood but can present in infancy to adulthood. An autosomal dominant disorder due to mutation of a nicotinic acetylcholine receptor. Fear is a dominant symptom for the patient during episodes. Paroxysmal events present similarly to parasomnia, panic attacks, and psychogenic non-epileptic seizures due to retained consciousness. POLG related epilepsy POLG (polymerase gamma) is a mitochondrial gene responsible for mitochondria DNA replication and repair. Onset is usually in early childhood (1-5 years) or adolescence. A seizure is the first symptom in half of patients, while others first present with failure to thrive, hypotonia, and developmental delay. Seizures are usually occipital, but the presentation is variable. Seizures tend to be refractive and hard to control to medical management. Valproic acid is an absolute contraindication due to its effect on mitochrondrial metabolism. Rasmussen encephalitis (chronic focal epilepsy, CFE) Presents between 18 months and 14 years of age with frequent focal seizures that can evolve to epilepsia partialis continua (EPC) and progressive neurologic deficits. MRI brain will show unilateral hemispheric changes in white matter and then atrophy. EEG will show focal and multifocal epileptiform discharges, slowing and progressive seizures over time. Associated in some patients with GluRε2 (anti-NR2A) or GluR3 (AMPA receptor) genes. Treatment with hemispherectomy is often required. Juvenile Myoclonic Epilepsy (JME) The most common form of idiopathic epilepsy. Presents between 8-26 years of age with morning myoclonic jerks and generalized seizures. 33% also have absence seizures. Myoclonus of fingers presents as "clumsiness" and dropping things. Seizures are often precipitated by sleep deprivation, drugs and/or alcohol. Interictal EEG will show generalized 4-6 Hz polyspike and wave discharges. Myoclonic jerks or runs of spikes can be brought on by photic stimulation. Treatment: Valproic acid is the treatment of choice. Lamotrigine is a second option, or for women of childbearing age. Levetiracetam, topiramate, and zonisamide are additional options. Carbamazepine, phenytoin, gabapentin, pregabalin, tiagabine, and vigabatrin can worsen myoclonic seizures. Mesial temporal sclerosis (MTS) The most common structural abnormality in temporal lobe epilepsy. Usually presents with focal seizures with impaired awareness due to ictal involvement of the hippocampus. Severe febrile seizures can be a risk factor. Imaging: Atrophy and hyperintensity on T2 sequences of the mesial temporal lobe (unilateral) with thinning of the cortical ribbon. Pathology: Gliosis and neuronal loss of the hippocampal CA1 pyramidal cell layer with CA3 and CA4 somewhat less involved. Area CA2 is relatively spared. Focal Cortical Dysplasia (FCD) Presents with focal epilepsy secondary to dysfunctional cell migration during neurodevelopment. Imaging will show focal cortical thickening. FCD can be classified based on pathological analysis using Blumcke classification (2011): FCD Type I: Aberrant microcolumns (Type IA), loss of individual cortical layers (Type IB), or both (Type IC) represent cortical architecture abnormalities. FCD Type IIA: Dysmorphic neurons. FCD Type IIB: Dysmorphic neurons plus balloon cells. Heterotopia Abnormal areas of grey matter often found in periventricular regions due to migration error. Migration errors can occur secondary to an in utero insult or a genetic cause. Cortical hamartomas Seen in patients with tuberous sclerosis. Pathology will show disorganized, enlarged atypical neuronal and glial cells. Hypothalamic hamartoma Presents with gelastic epilepsy (laughing seizures). MRI will show a round well-circumscribed iso-intense non-enhancing lesion in the hypothalamus protruding into the 3rd ventricle. Precocious puberty may occur as well. Progressive Myoclonic Epilepsy (PME) Represents a quorum of neurological disorders which present with progressive myoclonic seizures, ataxia and a decline in motor skills and cognition over time. Typically presents between 6 and 15 years of age. Antibiotics Carbapenems, fluoroquinolones, cefepime Antidepressants Bupropion, tricyclic (amitriptyline) Antipsychotic Clozapine, chlorpromazine Immunosuppressants Azathrioprine, cyclosprine, tacrolimus Anticancer Cisplatin, Vinblastine, Infereron alpha Status Epilepticus Defined as generalized seizure activity for longer than 5 minutes or multiple seizures without a return to baseline over 5 minutes. IV/IM benzodiazepines What are FIRST LINE MEDS for Status Epileptiucus? hypoglycemia What should patients first be evaluated for when they are in status? Levetiracetam, valproic acid, or phenytoin/fosphenytoin What are SECOND LINE MEDS for status if Benzodiazapines fail to break seizures? Nonconvulsive status epilepticus (NCSE) Presents with an abrupt change in mental status without motor semiology. If performed an EEG will confirm continuous seizure activity. Epilepsy partialis continua (EPC) A variant of status epilepticus that Involves a focal region of cortex and may not be well represented on the scalp EEG. Typically seen in patients with a history CNS malignancy.