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Pathogenic variants in GABRB3have been associated with a spectrum of phenotypes from severe developmental disorders and epileptic encephalopathies to milder epilepsy syndromes and mild intellectual disability (ID). In this study, we analyzed a large cohort of individuals with GABRB3variants to deepen the phenotypic understanding and investigate genotype–phenotype correlations.

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Aim. Epilepsy is difficult to diagnose using routine EEG recordings of short duration in patients who have low seizure frequency. Long‐term EEG may be useful but is impractical in an out‐of‐hospital setting. We investigated whether single‐channel scalp EEG placed behind the earlobe is suitable for seizure identification during prolonged EEG monitoring. Methods. Scalp EEG samples were selected from subjects over 15 years of age, and comprised two segments of either background followed by seizure or background followed by background. Bipolar EEG derivations in three directions (F8‐T8, C4‐T8 and T8‐P8) were evaluated for the presence of a seizure by two experienced reviewers. For each EEG segment containing a seizure, one pair of electrodes was oriented towards the suspected region of seizure onset, while two pairs of electrodes were oriented elsewhere. Results. The EEG data contained five frontally localized seizures, five parietal, five temporal, two occipital, and four primary or secondary generalized seizures. The sensitivity and specificity for recognition of seizures was 86% and 95% for Reviewer 1, and 79% and 99% for Reviewer 2, respectively. When identifying a seizure with the lead orientation towards the region of seizure onset, both reviewers identified 20 out of 21 seizures (95%). When the lead was not oriented towards the region of seizure onset, the reviewers identified 34 and 30 out of 42 ictal records correctly, respectively. Conclusions. These results suggest that it is possible to identify epileptic seizures by bipolar EEG derivation using only two scalp electrodes. Lead orientation towards the suspected region of seizure onset is important for optimal detection sensitivity.

To determine the occurrence of residual loss of peripheral nerve axons by motor unit number estimation (MUNE) and conventional nerve conduction studies (NCS) in patients with and without severe fatigue.

The case history is the cornerstone for the diagnosis of carpal tunnel syndrome (CTS). The value of neurological examination in CTS seems limited. In this study, we investigated the interobserver agreement in case history of CTS and the potential additional value of neurological examination.

The objective of this review was to evaluate the available medical literature concerning the electroencephalogram (EEG) during hypertensive disorders of pregnancy. All articles found during a MEDLINE and Embase database search on the subject of EEG differences associated with hypertensive disorders in pregnancy were screened for eligibility. In all, 22 articles which describe the EEG during preeclampsia (PE)/eclampsia were retrieved. Abnormal EEG findings were observed in the majority of the preeclamptic/eclamptic patients, consisting of slow waves most frequently localized in the occipital lobe, as well as spike discharges. The EEG abnormalities in PE/eclampsia were reversible in the majority of the cases. We conclude that these described abnormalities may be interpreted as a warning sign of deterioration of brain function in PE/eclampsia. However, some caution regarding this conclusion is advised because most of the retrieved articles were published in the 1950s and 1960s, and were not consistent with current clinical guidelines or medical terminology. Further research is needed to establish the clinical value of implementing EEGs in the assessment of the preeclamptic/eclamptic patient.

A 43-year-old man of normal intelligence consulted our outpatient clinic for nocturnal events that had started at age 32 years. These arise from sleep when he suddenly awakens, experiencing fear and the sensation of falling into a black hole or choking. He recalls raising his body and turning his head but does not recall what happens afterwards. His partner reported the events to be stereotyped, and occurring mostly after 1–2 hours of sleep. After rising, he falls backwards in the bed and jerks his arms and legs. He is unconscious for 3–5 minutes. Afterwards, he is confused and disorientated, and sometimes wanders through the house. These events occur once every 2 months and are debilitating. They affect his relationship and cause daytime sleepiness. Serial EEGs (including sleep deprivation), polysomnography, and MRI of the brain were normal. The individual was referred to our clinic for a 24-hour EEG video recording aiming to record an event. This EEG showed sporadic interictal epileptiform discharges (sharp waves, slow spike wave complexes), predominantly over the left frontotemporal area, but also over the right frontotemporal and frontal areas. During the night, 4 almost identical events occurred during non-REM (NREM) 1 and 2 sleep. In these events, the patient abruptly rose from the bed, looked around with an anxious expression, and went back to sleep after less than 20 seconds. In 2 events, an extension of the right hand was noted. The episodes were not followed by a phase of limb-shaking or by disorientation. He did not call the nursing staff or remember the episodes afterwards. The EEG showed a K-complex at the beginning of each of these events, followed by a diffuse 11–12 Hz rhythm for several seconds, and was once followed by a short delta rhythm over the left frontotemporal region (figure). The episodes were accompanied by an acceleration of heart rate (from 54 to 72 bpm). After the event, when he closed his eyes again, a normal posterior dominant α rhythm was seen. As the events did not clinically resemble a physiologic arousal (due to the abrupt onset, marked stereotypy, and the tonic extension of the right hand), and in combination with the consistent (ictal) EEG findings, these episodes were considered to be of epileptic origin, and a diagnosis of NFLE was made (with paroxysmal arousals, sometimes with secondary generalization). Based on our findings during the EEG video recording, we speculated that the patient probably had more seizures than previously reported, which could also explain the excessive daytime sleepiness (EDS). Treatment was started with levetiracetam 1,000 mg twice daily and he became seizure-free. Moreover, EDS disappeared, confirming our hypothesis.

Ictal nystagmus (IN) is an uncommon phenomenon characterized by rhythmic saccadic eye movements occurring during epileptic seizures. We report a newborn baby with severe birth asphyxia, undergoing long-term video EEG monitoring with electro-oculogram (EOG), who showed irregular IN when eye movements crossed the midline from left to right and vice versa, resulting in large amplitude of the nystagmoid movements. The nystagmus was followed 15 to 29 seconds later by ictal discharges in the occipital regions. MRI of the brain showed features suggestive of periventricular leukomalacia. This interesting combination of findings suggests a complex mechanism for IN of cortical or subcortical ictal rhythms, which results in (a) the generation of subcortical electrical discharges in the pons and midbrain, causing nystagmoid eye movements, and (b) subsequent occipital spiking. We conclude that this clinical manifestation supports the existence of functioning cortical-subcortical connections between the brainstem ocular motor centers and the occipital cortex at birth.

In this article we propose a workflow for creating geologically realistic depth to basement maps and apply it to the undercover area of Cloncurry, located in the Mount Isa province, Queensland. A magnetotelluric (MT) survey consisting of 457 soundings was inverted using a 1D trans‐dimensional Bayesian algorithm designed to be robust to non‐1D effects present in the data. Automated change‐point analysis was then used to derive probability distributions on basement depth for each site independently. These were laterally combined, along with drill hole data and a structural model derived from aeromagnetic and geological data, using a Bayesian estimate fusion algorithm to create a region wide depth to basement probabilistic map. Combining many different constraints in this way lead to a significant reduction in posterior uncertainty. Individual MT site change‐point posteriors were highly multi‐modal in certain areas, with multiple resistivity transitions that could correspond to the cover‐basement interface. The estimate fusion process correlates these uncertainties and the combined posterior was thus much less multi‐modal. Our results show that the sedimentary cover gradually thickens toward the north, while toward the east its thickening is controlled by a two‐steps fault system. This workflow highlights the value gained from integrating different types of geoscientific data but also shows the capability of the MT method used within a probabilistic workflow to accurately image depth to basement even using limited constraints and assumptions. Within regions covered by sediments, defining the basement geometry underneath is essential to understand the distribution of mineral and groundwater resources. This study introduces a methodology and applies it to characterize the buried basement geometry in the Cloncurry region (90 km × 60 km area) of Queensland, which is a well‐known metallogenic province in Australia. The methodology we present uses independent estimates of depth to basement derived using data from different sources (electromagnetic geophysics and drill holes) and geological constraints on it, all providing complementary information, at many locations over the entire area. This produces a map of depth to basement, alongside a quantitative estimation of its reliability, which is based on uncertainty analysis of the various data inputs and their combination. This workflow produced a geologically realistic probability image which highlights the value of our workflow to integrate different types of data in a flexible and robust manner. Magnetotelluric data used within a probabilistic workflow is a reliable tool to derive a realistic depth to basement probabilistic mapThe uncertainty of the probabilistic map derived can be significantly reduced by combining many different probabilistic constraintsThe semi‐automated probabilistic workflow we present is mainly data‐driven and relies on limited expert assumptions Magnetotelluric data used within a probabilistic workflow is a reliable tool to derive a realistic depth to basement probabilistic map The uncertainty of the probabilistic map derived can be significantly reduced by combining many different probabilistic constraints The semi‐automated probabilistic workflow we present is mainly data‐driven and relies on limited expert assumptions

Objectives. The aim was to study the physiological effects of induced ventricular fibrillation and subsequent circulatory arrest for defibrillation threshold testing on the brain using the EEG, jugular bulb oxymetry and near-infrared spectroscopy. Methods. Thirteen patients undergoing surgery for implantable cardioverter-defibrillator implantation or replacement under general anesthesia were included. We continuously monitored the jugular bulb oxygen saturation (SjO2), regional oxygen saturation (rSO2) and the EEG. Results. 59 episodes of circulatory arrest were studied. In all cases the rSO2fell instantly while the EEG changed within 12 ± 4 seconds after induction. The EEG indicated ischemic changes, ranging from occurrence of rhythmic delta activity to cessation of all electrical activity. On successful defibrillation the rSO2increased to values in excess of pre-arrest levels and restored towards baseline; the SjO2initially fell followed by a similar overshoot. Recovery times increased in proportion to arrest duration. Conclusion. Short lasting episodes of circulatory arrest have serious, but transient effects on brain function. The rSO2is an effective non-invasive tool for monitoring cerebral oxygenation during DFT-testing.