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Transcranial magnetic stimulation (TMS) with electroencephalography (EEG), that is TMS‐EEG, may assist in managing epilepsy. We systematically reviewed the quality of reporting and findings in TMS‐EEG studies on people with epilepsy and healthy controls, and on healthy individuals taking anti‐seizure medication. We searched the Cochrane Library, Embase, PubMed and Web of Science databases for original TMS‐EEG studies comparing people with epilepsy and healthy controls, and healthy subjects before and after taking anti‐seizure medication. Studies should involve quantitative analyses of TMS‐evoked EEG responses. We evaluated the reporting of study population characteristics and TMS‐EEG protocols (TMS sessions and equipment, TMS trials and EEG protocol), assessed the variation between protocols, and recorded the main TMS‐EEG findings. We identified 20 articles reporting 14 unique study populations and TMS methodologies. The median reporting rate for the group of people with epilepsy parameters was 3.5/7 studies and for the TMS parameters was 13/14 studies. TMS protocols varied between studies. Fifteen out of 28 anti‐seizure medication trials in total were evaluated with time‐domain analyses of single‐pulse TMS‐EEG data. Anti‐seizure medication significantly increased N45, and decreased N100 and P180 component amplitudes but in marginal numbers (N45: 8/15, N100: 7/15, P180: 6/15). Eight articles compared people with epilepsy and controls using different analyses, thus limiting comparability. The reporting quality and methodological uniformity between studies evaluating TMS‐EEG as an epilepsy biomarker is poor. The inconsistent findings question the validity of TMS‐EEG as an epilepsy biomarker. To demonstrate TMS‐EEG clinical applicability, methodology and reporting standards are required. [ABSTRACT FROM AUTHOR]

Introduction: The lack of reliable biomarkers constrain epilepsy management. We assessed the potential of repeated transcranial magnetic stimulation with electromyography (TMS‐EMG) to track dynamical changes in cortical excitability on a within‐subject basis. Methods: We recruited people with refractory focal epilepsy who underwent video‐EEG monitoring and drug tapering as part of the presurgical evaluation. We performed daily TMS‐EMG measurements with additional postictal assessments 1–6 h following seizures to assess resting motor threshold (rMT), and motor evoked potentials (MEPs) with single‐ and paired‐pulse protocols. Anti‐seizure medication (ASM) regimens were recorded for the day before each measurement and expressed in proportion to the dosage before tapering. Additional measurements were performed in healthy controls to evaluate day‐to‐day rMT variability. Results: We performed 77 (58 baseline, 19 postictal) measurements in 16 people with focal epilepsy and 35 in seven healthy controls. Controls showed minimal day‐to‐day rMT variation. Withdrawal of ASMs was associated with a lower rMT without affecting MEPs of single‐ and paired‐pulse TMS‐EMG paradigms. Postictal measurements following focal to bilateral tonic–clonic seizures demonstrated unaltered rMT and increased short interval intracortical inhibition, while measurements following focal seizures with impaired awareness showed decreased rMT's and reduced short and long interval intracortical inhibition. Conclusion: Serial within‐subject rMT measurements yielded reproducible, stable results in healthy controls. ASM tapering and seizures had distinct effects on TMS‐EMG excitability indices in people with epilepsy. Drug tapering decreased rMT, indicating increased overall corticospinal excitability, whereas seizures affected intracortical inhibition with contrasting effects between seizure types. [ABSTRACT FROM AUTHOR]

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. Plain Language Summary: 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. Key Points: 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 [ABSTRACT FROM AUTHOR]

Background: The most common subtypes of Guillain-Barré syndrome (GBS) are acute inflammatory demyelinating polyneuropathy (AIDP) and acute motor axonal neuropathy (AMAN). In the first days after the onset of weakness, standard nerve conduction studies (NCS) may not distinguish GBS subtypes. Reduced nerve excitability may be an early symptom of nerve dysfunction, which can be determined with the compound muscle action potential (CMAP) scan. The aim of this study was to explore whether early changes in motor nerve excitability in GBS patients are related to various subtypes.Methods: Prospective case-control study in 19 GBS patients from The Netherlands and 22 from Bangladesh. CMAP scans were performed within 2 days of hospital admission and NCS 7-14 days after onset of weakness. CMAP scans were also performed in age- and country-matched controls.Results: CMAP scan patterns of patients who were classified as AMAN were distinctly different compared to the CMAP scan patterns of the patients who were classified as AIDP. The most pronounced differences were found in the stimulus intensity parameters.Conclusions: CMAP scans made at hospital admission demonstrate several characteristics that can be used as an early indicator of GBS subtype. [ABSTRACT FROM AUTHOR]

Summary: People with epilepsy need assistance and are at risk of sudden death when having convulsive seizures (CS). Automated real‐time seizure detection systems can help alert caregivers, but wearable sensors are not always tolerated. We determined algorithm settings and investigated detection performance of a video algorithm to detect CS in a residential care setting. The algorithm calculates power in the 2‐6 Hz range relative to 0.5‐12.5 Hz range in group velocity signals derived from video‐sequence optical flow. A detection threshold was found using a training set consisting of video‐electroencephalogaphy (EEG) recordings of 72 CS. A test set consisting of 24 full nights of 12 new subjects in residential care and additional recordings of 50 CS selected randomly was used to estimate performance. All data were analyzed retrospectively. The start and end of CS (generalized clonic and tonic–clonic seizures) and other seizures considered desirable to detect (long generalized tonic, hyperkinetic, and other major seizures) were annotated. The detection threshold was set to the value that obtained 97% sensitivity in the training set. Sensitivity, latency, and false detection rate (FDR) per night were calculated in the test set. A seizure was detected when the algorithm output exceeded the threshold continuously for 2 seconds. With the detection threshold determined in the training set, all CS were detected in the test set (100% sensitivity). Latency was ≤10 seconds in 78% of detections. Three/five hyperkinetic and 6/9 other major seizures were detected. Median FDR was 0.78 per night and no false detections occurred in 9/24 nights. Our algorithm could improve safety unobtrusively by automated real‐time detection of CS in video registrations, with an acceptable latency and FDR. The algorithm can also detect some other motor seizures requiring assistance. [ABSTRACT FROM AUTHOR]

Objective Following a sudden death at a residential care unit, the Dutch Health and Care Inspectorate advised intensification of the use of video monitoring ( VM) at the unit. We assessed whether VM resulted in increased identification of seizures that required clinical intervention. Methods The unit provides care for 340 individuals with refractory epilepsy and severe learning disabilities. Acoustic detection systems ( ADSs) cover all individuals; 37 people also have a bed motion sensor ( BMS) and 46 people with possible nocturnal seizures are now monitored by VM. During a 6-month period, in all cases of a suspected seizure we asked the caregivers to specify which device alerted them and to indicate whether this led to an intervention. Staff costs of VM were estimated using payroll information. Results We identified 1,208 seizures in 37 individuals: 4 had no nocturnal seizures and 393 (33%) seizures were seen only on video. In 169 (14%) of 1,208 seizures an intervention was made and this included 39 (10%) of 393 seizures seen only on video. When compared to seizures observed with an ADS or BMS, seizures seen only on video were more often tonic seizures (71% vs. 22%, p < 0.001) and occurred mostly in the beginning or at the end of the night (40% vs. 26%, p < 0.001). The extra staff costs of monitoring was 7,035 euro per seizure seen only on video and leading to an intervention. Significance VM facilitates nocturnal surveillance, but the costs are high. This underscores the need for development of reliable seizure detection devices. [ABSTRACT FROM AUTHOR]

Introduction: Fasciculations, the spontaneous activity of single motor units (MUs) are characteristic, but nonspecific for motor neuron disease (MND). We aimed to identify MU discharge properties to optimally differentiate MND patients from healthy controls.Methods: High-density surface electromyography recordings were performed in the thenar muscles during 10 min of rest. MU discharges were classified as "isolated" when the interspike intervals (ISIs) before and after were > 250 ms, "continual" when both ISIs were ≤ 250 ms, or as "other".Results: In patients (n = 30) compared with controls (n = 14), more MUs were active (9 vs. 3, P < 0.001) and generated relatively more isolated discharges (35% vs. 10%, P = 0.01). Two or more MUs with isolated discharges occurred more frequently in patients compared with controls (24% vs. <1% of 10-s windows, P < 0.001).Conclusions: More frequent occurrence of multiple MUs showing isolated discharges may improve identification of patients with MND. [ABSTRACT FROM AUTHOR]

Introduction: The aim of this study was to determine whether electrically evoked multiplet discharges (MDs) are related to severity of clinical deterioration in motor neuron disease (MND).Methods: Stimulated high-density surface electromyographic (HDsEMG) recordings were performed in thenar muscles. Data were collected from 31 MND patients. MDs from the HDsEMG recordings were determined at baseline. ALSFRS-R scores were obtained at baseline and at a maximum of 16 weeks follow-up.Results: The presence of MDs was associated with progressive deterioration of ALSFRS-R score (P = 0.02) and fine motor function (FMF) (P < 0.001). Patients who had a higher number of motor units that generated MDs (r = 0.61, P < 0.001) and patients who had a higher number of MDs (as percentage of applied stimuli) (r = 0.59, P = 0.001) had a more severe decline in FMF.Conclusions: Electrically evoked MDs are associated with more marked clinical deterioration in patients with MND. [ABSTRACT FROM AUTHOR]

Objective To define reference values of the patellar reflex in normotensive pregnant and postpartum women and to compare these with values in women with preeclampsia. Design Observational study. Setting University teaching hospital in the Netherlands. Population Normotensive non-pregnant women, pregnant women and preeclamptic women. Methods In normotensive pregnant women the patellar reflex was cross-sectionally recorded using surface electromyography at four time points during pregnancy and six to eight weeks postpartum. In non-pregnant normotensive women this was recorded once. Preeclamptic women were recorded during pregnancy and postpartum. Main outcome measures Latency and amplitude of the compound muscle action potential of the patellar reflex. Results Latency and amplitude of the compound muscle action potential during normotensive pregnancies showed no changes compared with the non-pregnant state during reproductive age. Latency of the compound muscle action potential was increased in pregnancies with severe preeclampsia compared with normotensive pregnancies. These differences disappeared postpartum. Conclusions During pregnancy, the patellar reflex can be assessed using surface electromyography. Latency and amplitude show no changes during normotensive pregnancies and are no different from the postpartum or non-pregnant values. In severely preeclamptic women, latency is increased. The clinical value of this is limited. [ABSTRACT FROM AUTHOR]

Cerebral perfusion pressure ( CPP) is elevated in preeclampsia, and may predispose to cerebrovascular complications and progression to eclampsia. We estimated zero flow pressure ( ZFP) and CPP using simultaneously obtained arterial blood pressure and middle cerebral artery blood flow velocity in 10 women with preeclampsia, all treated with methyldopa with or without nifedipine, and 18 healthy pregnant controls. Mean ± SD ZFP was lower in women with preeclampsia than in controls (16.8 ± 10.9 vs. 31.7 ± 15.0 mmHg, p = 0.01) whereas CPP was considerably higher (82.3 ± 17.7 vs. 55.0 ± 11.7 mmHg, p < 0.001), as was the cerebral flow index (41.9 ± 18.0 vs. 25.6 ± 11.2, p = 0.02). There was a significant correlation between blood pressure and CPP in women with preeclampsia, but not in controls. Women with preeclampsia may have an increased cerebral perfusion due to a reduced ZFP and increased CPP despite treatment with antihypertensive medication. More rigorous antihypertensive therapy, aimed at reducing CPP, could result in a decrease in cerebral complications in women with preeclampsia. [ABSTRACT FROM AUTHOR]

Even though it is known that neonatal seizures are associated with acute brain lesions, the relationship of electroencephalographic (EEG) seizures to acute perinatal brain lesions visible on magnetic resonance imaging (MRI) has not been objectively studied. EEG source localization is successfully used for this purpose in adults, but it has not been sufficiently explored in neonates. Therefore, we developed an integrated method for ictal EEG dipole source localization based on a realistic head model to investigate the utility of EEG source imaging in neonates with postasphyxial seizures. We describe here our method and compare the dipole seizure localization results with acute perinatal lesions seen on brain MRI in 10 full-term infants with neonatal encephalopathy. Through experimental studies, we also explore the sensitivity of our method to the electrode positioning errors and the variations in neonatal skull geometry and conductivity. The localization results of 45 focal seizures from 10 neonates are compared with the visual analysis of EEG and MRI data, scored by expert physicians. In 9 of 10 neonates, dipole locations showed good relationship with MRI lesions and clinical data. Our experimental results also suggest that the variations in the used values for skull conductivity or thickness have little effect on the dipole localization, whereas inaccurate electrode positioning can reduce the accuracy of source estimates. The performance of our fused method indicates that ictal EEG source imaging is feasible in neonates and with further validation studies, this technique can become a useful diagnostic tool. Hum Brain Mapp 34:2402-2417, 2013. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The electroencephalography ( EEG) signal has a high complexity, and the process of extracting clinically relevant features is achieved by visual analysis of the recordings. The interobserver agreement in EEG interpretation is only moderate. This is partly due to the method of reporting the findings in free-text format. The purpose of our endeavor was to create a computer-based system for EEG assessment and reporting, where the physicians would construct the reports by choosing from predefined elements for each relevant EEG feature, as well as the clinical phenomena (for video- EEG recordings). A working group of EEG experts took part in consensus workshops in Dianalund, Denmark, in 2010 and 2011. The faculty was approved by the Commission on European Affairs of the International League Against Epilepsy (ILAE). The working group produced a consensus proposal that went through a pan- European review process, organized by the European Chapter of the International Federation of Clinical Neurophysiology. The Standardised Computer-based Organised Reporting of EEG ( SCORE) software was constructed based on the terms and features of the consensus statement and it was tested in the clinical practice. The main elements of SCORE are the following: personal data of the patient, referral data, recording conditions, modulators, background activity, drowsiness and sleep, interictal findings, 'episodes' (clinical or subclinical events), physiologic patterns, patterns of uncertain significance, artifacts, polygraphic channels, and diagnostic significance. The following specific aspects of the neonatal EEGs are scored: alertness, temporal organization, and spatial organization. For each EEG finding, relevant features are scored using predefined terms. Definitions are provided for all EEG terms and features. SCORE can potentially improve the quality of EEG assessment and reporting; it will help incorporate the results of computer-assisted analysis into the report, it will make possible the build-up of a multinational database, and it will help in training young neurophysiologists. [ABSTRACT FROM AUTHOR]

Typical Miller Fisher syndrome (MFS) lacks limb muscle weakness, but some patients may unpredictably progress to severe Guillain-Barré syndrome. The compound muscle action potential (CMAP) scan is a recently developed non-invasive, painless, and reproducible method for detecting early changes in motor nerve excitability. This technique was used to monitor subclinical limb motor nerve dysfunction during disease course in typical MFS. Three Miller Fisher patients with preserved limb muscle strength and normal routine nerve conduction studies were included. Frequent serial CMAP scanning of the median nerve was performed during acute phase and follow-up and was related to clinical course and outcome. All patients showed an abnormal increase in the range of stimulus intensities at the day of hospital admission, indicating reduced motor nerve excitability already at the earliest stage of disease. Median nerve dysfunction progressed in parallel or even before clinical deterioration, and improved with clinical recovery. Our study shows that typical MFS is a more general neuropathy, affecting peripheral motor nerves even in patients with preserved limb strength and conduction velocity. CMAP scanning is a sensitive technique for early detection of subclinical motor nerve dysfunction and for monitoring disease activity in immune-mediated neuropathies. [ABSTRACT FROM AUTHOR]

Ultrasound-guided near-nerve neurography is a new tool that can be used to assess nerve regeneration before reinnervation occurs. In this study, ultrasound-guided near-nerve measurements were validated against axon diameter counts in rabbits during a 15-week regeneration period after a crush lesion of their peroneal nerve. The course of the nerve was determined ultrasonically, and the active near-nerve needle electrode was maneuvered just next to the nerve under ultrasound guidance. Measured action potentials were compared with axon diameter counts from histological sections of these same nerves. A moderate to good positive correlation was found, which reached a maximum of 0.7 at a cut-off of 3 μm, corresponding to the minimal size of the myelinated axons. Our results suggest that, following a similar validation study in humans, ultrasound-guided near-nerve neurography may be clinically useful when early evaluation of nerve activity is needed. Muscle Nerve, 2009 [ABSTRACT FROM AUTHOR]

Cerebellar stroke has been virtually unreported in the living newborn infant. A term newborn male weighing 3380g at birth suffered myoclonic seizures within 24 hours of birth by spontaneous vaginal delivery. Apgar scores were 3 and 4 at 1 and 5 minutes. Myoclonus persisted for 9 days, responding poorly to step-up anticonvulsant treatment including lidocaine, midazolam, and clonazepam. Imaging documented arterial ischaemic stroke within the left posterior cerebral and both superior cerebellar arteries, compatible with top of the basilar artery stroke. There was no electrographic correlate for the seizures. Disturbed oscillation within the dentato-rubro-olivary circuitry was the likely mechanism. The probable cause was embolism from an in-utero-onset inferior caval vein thrombosis. At 22 months the child was sitting unsupported. Scores on the Bayley Scales of Infant Development II were equivalent to those of a 12-month-year-old. He showed ataxic motor behaviour. Embolism can cause neonatal top of the basilar artery stroke, which may present with myoclonus due to cerebellar injury. [ABSTRACT FROM AUTHOR]

This study aims to assess the potential of the electrophysiological muscle scan or stimulus-response curve as a diagnostic instrument. If stimulus intensity is gradually increased from subthreshold to supramaximal values, all motor units in a muscle are successively activated. Thus, by plotting response size versus stimulus intensity, an impression (scan) of the entire muscle can be obtained. We recorded 54 detailed scans from 34 patients and 11 healthy subjects, and analyzed them visually and quantitatively. The scan summarized much diagnostic information in a single picture. Specific patterns in or properties of the scan (steps, maximum, variability, decrements, stimulus intensities used) provide clinically relevant information regarding motor unit number, size, and stability, and neuromuscular transmission and axonal excitability. The scan can be recorded noninvasively in about 5 minutes and is fairly easy to interpret. Because it is built up from contributions of all functioning motor units, the scan shows if and how many large motor units are present. There is no sample bias. For these reasons, further exploration and exploitation of this tool in the clinical setting are warranted. Muscle Nerve, 2007 [ABSTRACT FROM AUTHOR]

Experimental assessment of peripheral nerve regeneration in rats by electrophysiology is controversial due to low reproducibility of electrophysiological indicators and diminished quantitative evaluation in conventional experimental set-ups. Magnetoneurography (MNG) counteracts these drawbacks by magnetically recording electrophysiological signals ex vivo, thereby providing accurate and quantitative data. In 50 rats, sciatic nerve transection was followed by direct repair. MNG outcome parameters, footprints [static toe spread factor (TSF); function] and muscle weight (MW) were studied for their recovery pattern from 2 to 24 weeks. By using MNG, we showed that the regeneration process still continues when functional recovery (static TSF) becomes stagnant. With regression analysis, MNG parameters amplitude, amplitude area and conduction velocity (CV) demonstrated moderate significant correlation with MW, whereas CV was not significantly associated with static TSF. No significant association exists between MW and static TSF. A Kaplan–Meier survival curve revealed that autotomy/contracture of rat hind paws was not related to decreased MNG outcome values. In conclusion, this study highlights and discusses the dissimilarities between direct (MNG) and indirect (static TSF and MW) assessment techniques of the regeneration process. We emphasise the significance of MNG as a direct derivative of axon regeneration in experimental rat studies. Additionally, we stress the must for right-left ratios, as neurophysiological indicators vary with age, and we confute possible bias in footprint analysis caused by exclusion of autotomy/contracture animals. [ABSTRACT FROM AUTHOR]

Ultrasound imaging of peripheral nerves is increasingly used in the clinic for a wide range of applications. Although yet unapplied for experimental neuroscience, it also has potential value in this research area. This study explores the feasibility, possibilities and limitations of this technique in rabbits, with special focus on peripheral nerve regeneration after trauma. The peroneal nerve of 25 New Zealand White rabbits was imaged at varying time intervals after a crush lesion. The ultrasonic appearance of the nerve was determined, and recordings were validated with in vivo anatomy. Nerve swelling at the lesion site was estimated from ultrasound images and compared with anatomical parameters. The peroneal nerve could reliably be identified in all animals, and its course and anatomical variations agreed perfectly with anatomy. Nerve diameters from ultrasound were related to in vivo diameters (p < 0.001, R2 = 77%), although the prediction interval was rather wide. Nerve thickenings could be visualized and preliminary results indicate that ultrasound can differentiate between neuroma formation and external nerve thickening. The value of the technique for experimental neuroscience is discussed. We conclude that ultrasound imaging of the rabbit peroneal nerve is feasible and that it is a promising tool for different research areas within the field of experimental neuroscience. [ABSTRACT FROM AUTHOR]