Revised Electroencephalography Terminology and Clinical Consideration

Electroencephalography (EEG) has been used for decades to evaluate and assess brain function. It is a useful method to diagnose brain disorders. However, confirmed interpretation of EEG is quite challenging because there is no standardized method for EEG reading and this may lead to interrater variability even among expert electroencephalographers. In this background, uniformly accepted nomenclature for EEG pattern were required to improve interrater agreement and to support communication for EEG research. American Clinical Neurophysiology Society (ACNS) established the standardized critical care EEG terminology since 2012 and has recently published the revised 2021 version of EEG terminology. This review covers new concepts of 2021 ACNS EEG terminology and clinical considerations of various EEG patterns.

Two Focal Seizure in a Patient Caused by Different Mechanism

Poststroke epilepsy is the most common cause of epilepsy in adult. Acute symptomatic seizure is a provoked seizure usually caused by systemic metabolic disorders. If stroke patient has a seizure, it is very important to discriminate whether it is a poststroke epilepsy or provoked seizure. The reason is that there are differences in the approach to treatment and the continuation of antiepileptic drugs. We report a stroke mimic patient who had two different mechanisms of focal seizures.

Lower High-Density Lipoprotein Cholesterol Concentration Is Independently Associated with Greater Future Accumulation of Intra-Abdominal Fat

Background@#Both intra-abdominal fat (IAF) and high-density lipoprotein cholesterol (HDL-C) are known to be associated with cardiometabolic health. We evaluated whether the accumulation of computed tomography (CT)-measured IAF over 5 years was related to baseline HDL-C concentration in a prospective cohort study. @*Methods@#All participants were Japanese-Americans between the ages of 34 and 74 years. Plasma HDL-C concentration and CT measurements of IAF, abdominal subcutaneous fat (SCF), and thigh SCF cross-sectional areas were assessed at baseline and at 5-year follow-up visits. @*Results@#A total of 397 subjects without diabetes were included. The mean±standard deviation HDL-C concentration was 51.6±13.0 mg/dL in men and 66.0±17.0 mg/dL in women, and the IAF was 91.9±48.4 cm2 in men and 63.1±39.5 cm2 in women. The baseline plasma concentration of HDL-C was inversely associated with the change in IAF over 5 years using multivariable regression analysis with adjustment for age, sex, family history of diabetes, weight change over 5 years, and baseline measurements of body mass index, IAF, abdominal SCF, abdominal circumference, thigh SCF, and homeostatic model assessment for insulin resistance. @*Conclusion@#These results demonstrate that HDL-C concentration significantly predicts future accumulation of IAF over 5 years independent of age, sex, insulin sensitivity, and body composition in Japanese-American men and women without diabetes.

Lower High-Density Lipoprotein Cholesterol Concentration Is Independently Associated with Greater Future Accumulation of Intra-Abdominal Fat

Background@#Both intra-abdominal fat (IAF) and high-density lipoprotein cholesterol (HDL-C) are known to be associated with cardiometabolic health. We evaluated whether the accumulation of computed tomography (CT)-measured IAF over 5 years was related to baseline HDL-C concentration in a prospective cohort study. @*Methods@#All participants were Japanese-Americans between the ages of 34 and 74 years. Plasma HDL-C concentration and CT measurements of IAF, abdominal subcutaneous fat (SCF), and thigh SCF cross-sectional areas were assessed at baseline and at 5-year follow-up visits. @*Results@#A total of 397 subjects without diabetes were included. The mean±standard deviation HDL-C concentration was 51.6±13.0 mg/dL in men and 66.0±17.0 mg/dL in women, and the IAF was 91.9±48.4 cm2 in men and 63.1±39.5 cm2 in women. The baseline plasma concentration of HDL-C was inversely associated with the change in IAF over 5 years using multivariable regression analysis with adjustment for age, sex, family history of diabetes, weight change over 5 years, and baseline measurements of body mass index, IAF, abdominal SCF, abdominal circumference, thigh SCF, and homeostatic model assessment for insulin resistance. @*Conclusion@#These results demonstrate that HDL-C concentration significantly predicts future accumulation of IAF over 5 years independent of age, sex, insulin sensitivity, and body composition in Japanese-American men and women without diabetes.

Focal Subarachnoid Hemorrhage Mimicking Recurrent Transient Ischemic Attack

Focal subarachnoid hemorrhage occasionally presents as transient focal neurologic episodes mimicking transient ischemic attack (TIA). Unless properly diagnosed, it may aggravate cerebral hemorrhage by administering antithrombotic agents. Therefore, clinicians need to be aware that such focal subarachnoid hemorrhage sometimes cannot be detected on noncontrast computed tomography and blood-sensitive magnetic resonance imaging can detect even a small amount of hemorrhage. We describe an 85-year-old woman with focal subarachnoid hemorrhage and possible cerebral amyloid angiopathy who presented transient left arm weakness recurrently, which mimicked TIA.

Cerebral Heterotopia Presenting as Epilepsy with Auditory Aura

No abstract available.

Epilepsy and Driving Regulation in Korea

In Korea, current status of epilepsy and driving are challenging and there are lack of formal legal guidelines about driving in patients with epilepsy. According to the default standards in Korean Road Traffic law, patients with epilepsy are restricted or prohibited from driving except who are conditionally allowed to drive by the Aptitude Judgement Committee (AJC). Though the AJC consist of medical doctors and traffic officials, new regulation and guidelines are required for various type of seizure and characteristics of patients with epilepsy. This review outlines the current applicable legislation about epilepsy and driving in Korea as well as that of the overseas country calling for new laws to establish a consistent assessment.

Parasomnia as an Initial Presentation of Narcolepsy

Narcolepsy is characterized by excessive daytime sleepiness, cataplexy, sleep paralysis and hypnagogic hallucinations. Only a few studies have focused on non-rapid eye movement (NREM) and REM parasomnias in narcolepsy. We report a narcolepsy without cataplexy patient presenting parasomnia as an initial symptom. A 18-year-old boy was admitted to hospital for abnormal behavior of sitting up during sleep over 2 years. He had a symptom of lethargy without cataplexy and subjective excessive daytime sleepiness, but his family found him often asleep during daytime. He underwent 3 times of polysomnography (PSG) including 1 multiple sleep latency test (MSLT) after the last PSG. The last PSG showed 1 episode of abrupt sitting. Three sleep REM onset period was observed in MSLT which was not detect in PSG. Parasomnia as an initial symptom of narcolepsy is a rare clinical entity. The MSLT may be useful in the evaluation of patients with parasomnia and unexplained hypersomnia.

Hypoxic brain injury with unilateral hemispheric cortical involvement following multiple wasp stings

The most frequently reported neurological complication of a wasp sting is ischemic stroke. We treated a patient with wasp sting with unusual complications. A 52-year-old man was hospitalized for anaphylactic shock after multiple wasp stings. Although the patient recovered consciousness after 2 days, he had global aphasia and right hemiparesis. Brain magnetic resonance imaging and angiography revealed high-intensity signals in the left basal ganglia and cerebral cortex and stenosis of the left middle cerebral artery. After 2 days, the middle cerebral artery stenosis improved. After 5 days, diffusion-weighted imaging showed an enlarged lesion in the left frontal cortex. The infarct in this case was due to a predominantly unilateral vasoconstrictive hypoxic brain injury from wasp stings.

Concurrence of Acute Cerebral Infarction and Peripheral Neuropathy Associated with Hypereosinophilic Syndrome

Hypereosinophilic syndrome is a rare disorder involving the eosin concentration being elevated to more than 1500/µL in the peripheral blood for 6 months, and it causes various complications in the heart, skin, and nervous and respiratory systems. The simultaneous occurrence of neurological complications of hypereosinophilic syndrome is rare. Here we report a patient with hypereosinophilic syndrome who suffered from acute cerebral infarction and peripheral neuropathy during the same period.

Cerebral Embolic Infarction Caused by Aortic Arch Thrombus with Iron Deficiency Anemia

Atherosclerotic lesions at the aortic arch are recognized as critical sources of embolic strokes. However, there have been few case reports of aortic arch thrombus occurring without atherosclerotic changes, especially those related to iron deficiency anemia (IDA). A 44-year-old woman was admitted due to rapid-onset right hemiparesis and aphasia. Etiological investigations for cerebral infarction revealed no abnormality other than IDA. This is a rare case of cerebral embolic infarction caused by an aortic arch thrombus with IDA in a middle-aged woman.

Hypoglycemic Cognitive Impairment Presenting as Anomic Aphasia

No abstract available.

Wernicke Encephalopathy Associated with Acute Wet Beriberi

Wernicke encephalopathy is usually accompanied with peripheral neuropathy, known as dry beriberi. In contrast, wet beriberi presenting as cardiovascular symptoms rarely occurs. The acute type of wet beriberi can be fatal, if untreated quickly. It is reported that the cerebellar vermis has a role of the coordination and control of cardiovascular and autonomic reflex activities. We report a 58-year-old man showing acute wet beriberi in Wernicke encephalopathy with cerebellar vermis lesion.

Hypoxic Brain Injury with Bilateral Dentate Gyrus Involvement

No abstract available.

Histological Evidence of Artery to Artery Embolism from Calcified Atherosclerotic Plaque of Carotid Artery

Artery to artery embolism is one of the main causes of cerebral infarction, and it can originate from many locations. Here we report a case of cerebral infarction in which calcified cerebral emboli were detected in brain computed tomography (CT). The calcified emboli were thought to originate from a carotid plaque that showed calcification and ulceration. We present histologic and micro-CT findings of a carotid plaque as a source of artery to artery embolism.

Changes in Central Auditory Processing in Patients with Mesial Temporal Lobe Epilepsy after Anterior Temporal Lobectomy with Amygdalohippocampectomy

BACKGROUND AND PURPOSE: This study aimed to determine the effects of anterior temporal lobectomy with amygdalohippocampectomy (ATL-AH) on central auditory processing (CAP) in patients with mesial temporal lobe epilepsy with hippocampal sclerosis (mTLE-HS), and to identify factors that may contribute to the postoperative worsening of CAP. METHODS: Frequency-pattern, duration-pattern, and dichotic tests were performed before and after epilepsy surgery in 22 patients with normal hearing according to pure-tone audiometry. RESULTS: No significant difference in CAP scores was detected between pre- and postoperative tests, but there was a strong association between surgery in the language-dominant temporal lobe and postoperative worsening in the non-dominant-side dichotic test (p<0.05). The probability of a decreased performance in a non-dominant-side dichotic test after surgery was 7.5-fold greater in patients who underwent surgery on the dominant temporal lobe compared with the nondominant temporal lobe. No significant association of postoperative worsening in CAP with the verbal, nonverbal intelligence quotient, or right- or left-side lobectomy was noted. CONCLUSIONS: These results suggest that ATL-AH on the dominant side in patients with mTLE-HS worsens the CAP ability in the non-dominant-side dichotic test.

Movement-induced Reflex Seizure Caused by Focal Subarachnoid Hemorrhage

No abstract available.

Seizure Frequencies and Number of Anti-epileptic Drugs as Risk Factors for Sudden Unexpected Death in Epilepsy

The purpose of this study was to investigate the association between clinical variables and sudden unexpected death in epilepsy (SUDEP) and identify risk factors for SUDEP. SUDEP is one of the most frequent causes of death in patients with epilepsy. Previous studies have reported possible risk factors associated with SUDEP, but there need to be elucidated yet. The cases were 26 patients with SUDEP and three control patients were included for each case, matched for age, sex, and date of initial clinical visit. All demographic and clinical characteristics, including age, sex, disease duration, classification of epilepsy, age at seizure onset, kind and number of antiepileptic drugs, were compared between cases and controls. Seizure frequency was higher in SUDEP cases than in controls (P=0.035). Univariate analysis using conditional logistic regression showed that higher seizure frequency (odds ratio [OR]=3.1, P=0.021) and the number of antiepileptic drugs (AEDs) (OR=2.0, P=0.009) were significantly associated with SUDEP. Only the number of AEDs remained significant in multivariate analysis (OR=1.8, P=0.026). Frequent seizures and multi-drug therapy were associated with SUDEP. This may suggest that the severity of epilepsy is associated with SUDEP, regardless of the type of AED used.

Paraneoplastic Extralimbic Encephalitis Presenting with Partial Motor Clonic Seizure in a Patient with Invasive Thymoma

Paraneoplastic encephalitis presenting with partial clonic seizure is rare. We report a 57-year-old man with clonic seizure in his left arm. He had past medical history of recurrent thymoma and thymomectomy. Magnetic resonance imaging showed multiple brain lesions, but none of them were congruent with the partial seizure. His symptoms and brain lesions resolved after steroid therapy. This is the first reported case extralimbic encephalitis presenting as partial seizure with invasive thymoma in Korea.

Paraneoplastic Extralimbic Encephalitis Presenting with Partial Motor Clonic Seizure in a Patient with Invasive Thymoma

Paraneoplastic encephalitis presenting with partial clonic seizure is rare. We report a 57-year-old man with clonic seizure in his left arm. He had past medical history of recurrent thymoma and thymomectomy. Magnetic resonance imaging showed multiple brain lesions, but none of them were congruent with the partial seizure. His symptoms and brain lesions resolved after steroid therapy. This is the first reported case extralimbic encephalitis presenting as partial seizure with invasive thymoma in Korea.