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This is the second chapter of the series on the use of clinical neurophysiology for the study of movement disorders. It focusses on methods that can be used to probe neural circuits in brain and spinal cord. These include use of spinal and supraspinal reflexes to probe the integrity of transmission in specific pathways; transcranial methods of brain stimulation such as transcranial magnetic stimulation and transcranial direct current stimulation, which activate or modulate (respectively) the activity of populations of central neurones; EEG methods, both in conjunction with brain stimulation or with behavioural measures that record the activity of populations of central neurones; and pure behavioural measures that allow us to build conceptual models of motor control. The methods are discussed mainly in relation to work on healthy individuals. Later chapters will focus specifically on changes caused by pathology.

Clinical neurophysiology studies can contribute important information about the physiology of human movement and the pathophysiology and diagnosis of different movement disorders. Some techniques can be accomplished in a routine clinical neurophysiology laboratory and others require some special equipment. This review, initiating a series of articles on this topic, focuses on the methods and techniques. The methods reviewed include EMG, EEG, MEG, evoked potentials, coherence, accelerometry, coherence, posturography (balance), gait, and sleep studies. Functional MRI (fMRI) is also reviewed as a physiological method that can be used independently or together with other methods. A few applications to patients with movement disorders are discussed as examples, but the detailed applications will be the subject of other articles.

The objective of this clinical practice guideline (CPG) is to provide recommendations for healthcare personnel working with patients with epilepsy on the use of wearable devices for automated seizure detection in patients with epilepsy, in outpatient, ambulatory settings. The Working Group of the International League Against Epilepsy (ILAE) and the International Federation of Clinical Neurophysiology (IFCN) developed the CPG according to the methodology proposed by the ILAE Epilepsy Guidelines Working Group. We reviewed the published evidence using The Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statement and evaluated the evidence and formulated the recommendations following the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. We found high level of evidence for the accuracy of automated detection of generalized tonic-clonic seizures (GTCS) and focal-to-bilateral tonic-clonic seizures (FBTCS) and recommend the use of wearable automated seizure detection devices for selected patients when accurate detection of GTCS and FBTCS is recommended as a clinical adjunct. We also found a moderate level of evidence for seizure types without GTCS or FBTCS. However, it was uncertain whether the detected alarms resulted in meaningful clinical outcomes for the patients. We recommend using clinically validated devices for automated detection of GTCS and FBTCS, especially in unsupervised patients, where alarms can result in rapid intervention (weak/conditional recommendation). At present, we do not recommend clinical use of the currently available devices for other seizure types (weak/conditional recommendation). Further research and development are needed to improve the performance of automated seizure detection and to document their accuracy and clinical utility.

Objective To find and validate the optimal combination of criteria that define interictal epileptiform EEG discharges (IEDs). Our target was a specificity over 95%, to avoid over-reading in clinical EEG. Methods We constructed 63 combinations of the six criteria from the operational definition of IEDs, recently issued in the EEG-glossary of the International Federation of Clinical Neurophysiology (IFCN). The diagnostic gold standard was derived from video-EEG recordings. In a testing EEG dataset from 100 patients, we selected the best performing combinations of criteria and then we validated them in an independent dataset from 70 patients. We compared their performance with subjective, expert-scorings and we determined inter-rater agreement (IRA). Results Without using criteria, the specificity of expert-scorings was lower than the pre-defined threshold (86%). The best performing combination of criteria was the following: waves with spiky morphology, followed by a slow-afterwave and voltage map suggesting a source in the brain. In the validation dataset this achieved a specificity of 97% and a sensitivity of 89%. IRA was substantial. Conclusions The optimized set of criteria for defining IEDs has high accuracy and IRA. Significance Using these criteria will contribute to decreasing over-reading of EEG and avoid misdiagnosis of epilepsy.

Highlights • These guidelines provide orientation to perform clinical neurophysiological studies during COVID-19 pandemic. • Guide to perform protective procedures for healthcare personal doing clinical neurophysiological studies. • Offer a protocol for the disinfection of equipment and supplies in clinical neurophysiological studies., On 31st December 2019, China notified the World Health Organization of an outbreak of atypical pneumonia from patients at a local seafood market in Wuhan, Hubei, China, responsible for a new coronavirus called Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) that caused COVID-19 disease, which spread rapidly around the world. WHO declared a state of pandemic (11th March, 2020), which has caused more than 1 million infected and more than 110,000 deaths; it was observed that up to 29% of those infected were health care personnel. The main route of transmission of SARS-CoV2 is through respiratory secretions and direct contact with contaminated surfaces and material. The pandemic induced an international saturation of health care services and a rupture in the supply chain of protective equipment for healthcare personnel, which poses a high occupational risk to all. Based on the different healthcare systems, human resources, infrastructure and medical emergencies that will warrant the conduct of clinical neurophysiology studies and the lack of a guide for the management of the situation, it was decided by an expert task force of the Latin American Chapter of the International Federation of Clinical Neurophysiology to carry out these guidelines for the protection of patient and healthcare professionals conducting clinical neurophysiological studies.

Functional movement disorders are best diagnosed by positive features. Much can be done with the clinical examination, but often there are ambiguities. Further positive evidence can be obtained with clinical neurophysiology which can then lead to a “laboratory supported” diagnosis. The two entities for which clinical neurophysiology is useful are myoclonus and tremor. Functional tremor may well exhibit variability in frequency at different times or excessive fluctuations in the short term. The tremor might be in-phase in two different limbs, and this should not be the case except for orthostatic tremor. The tremor might entrain or be altered in frequency with tapping with another limb or be briefly interrupted by a quick movement of another limb. There might be a co-contraction sign where there is a co-contraction prior to the development of tremor. For functional myoclonus, the EMG activity shows long bursts of activity and often inconsistency with different jerks. EEG back-averaging can show a normal looking Bereitschaftspotential prior to the jerk. Comparison with a voluntary mimic or other voluntary movement is often valuable to see what the Bereitschaftspotential looks like in that individual. When the myoclonus is stimulus sensitive, the responses look like voluntary reaction time movements both in latency and variability. TMS can be used in functional paresis to demonstrate a normal pathway from motor cortex to muscle. Interestingly, this technique has sometimes also been therapeutic. Another feature of the TMS response in functional paresis is that the MEP amplitude decreases with movement imagination of that muscle. Since ordinarily imagination produces facilitation, this shows a high level inhibition of movement in the brain.

Objective To systematically study demographic, clinical, electrophysiological and nerve ultrasound characteristics of ulnar neuropathy with abnormal non-localizing electrophysiology (NL-UN) and further define the utility of ultrasound over and above the conventional electro-diagnostic approach. Method NL-UNs were prospectively identified from 113 consecutive referrals with suspected ulnar neuropathy. All received electro-diagnostic tests and ulnar nerve ultrasound. NL-UN severity was graded using clinical and electrophysiological scales. Results In 64 of 113 referrals, an ulnar mono- neuropathy was confirmed by electrophysiology. Sixteen of these 64 (25%) had NL-UN, predominantly males (14 out of 16 patients) with severe or moderate clinical and electrophysiological ratings. Ultrasound showed focal ulnar neuropathy at the elbow in 13 out of 16, and diffuse ulnar nerve abnormality in three, and identified a likely or possible causative mechanism in 11. Conclusion A significant proportion (a quarter) of ulnar neuropathies with abnormal electrophysiology were NL-UN, of heterogeneous etiology; the majority were males with significant disability and axonal loss. Ultrasound had a significant role in localization and classification that facilitated management. Significance To our knowledge, this is the first systematic prospective study that analyzes the demographic, clinical, electrophysiological and ultrasound characteristics of NL-UN in a routine clinical neurophysiology setting.

Objectives Rotation of a static magnet over the motor cortex (MC) generates a transcranial alternating magnetic field (tAMF), and a linked alternating electrical field. The aim of this transcranial magnetic stimulation (TMS) study is to investigate whether such fields are able to influence MC excitability, and whether there are parallels to tACS induced effects. Methods Fourteen healthy volunteers received 20 Hz tAMF stimulation over the MC, over the vertex, and 20 Hz tACS over the MC, each with a duration of 15 min. TMS assessments were performed before and after the interventions. Changes in motor evoked potentials (MEP), short interval intra-cortical inhibition (SICI) and intra-cortical facilitation (ICF) were evaluated. Results The tACS and the tAMF stimulation over the MC affected cortical excitability in a different way. After tAMF stimulation MEP amplitudes and ICF decreased and the effect of SICI increased. After tACS MEP amplitudes increased and there were no effects on SICI and ICF. Conclusions The recorded single and paired pulse MEPs indicate a general decrease of MC excitability following 15 min of tAMF stimulation. Significance The effects demonstrate that devices based on rotating magnets are potentially suited to become a novel brain stimulation tool in clinical neurophysiology.

Introduction. Electroencephalography (EEG) is a very important method in establishing epilepsy diagnosis but interpreting the result could be challenging for neurologists working in secondary hospitals. Smartphone-based telemedicine (SBTM) has been widely used but the application of this technology for EEG in Indonesia is not available yet. The 4G technology has covered approximately 82% of the country’s territory so we think there might be an opportunity to apply the SBTM to assist EEG in Indonesia. The study objective is to identify the need for EEG SBTM among neurologists in secondary hospitals in Indonesia. Methods. We made a web-based survey using a 14-items questionnaire made in Google Forms application. The target respondents were non-epilepsy/clinical neurophysiology consultant neurologists, working in non-type A hospitals, and operating an EEG machine. The questionnaire was designed to study the number of EEG cases, network connection, and the need for EEG SBTM. Results. There were 210 neurologists nationwide responded to the survey, representing about 15% of all neurologists in Indonesia, working in 32 of 34 provinces. Only 109 respondents were eligible. Most of them aged 41–50 years old and worked in North Sumatra, West Java, and Bali provinces (27.5%, 13.7%, and 9.2% subsequently). About 64.2% of them have 1–10 EEG cases monthly. Although >85% of the respondents had previous EEG training, 74% still encounter difficulty in interpretation. Only 1.8% do not have a smooth network connection. We found that 23.8% and 73% of them agreed and strongly agreed that they need an EEG SBTM. Respondents mostly prioritized the affordable submission fee, high data security, and bilingual options for the application. Conclusions. Most neurologists in secondary hospitals in Indonesia have problems in EEG interpretation and agreed that they need an EEG SBTM. This provides an opportunity to create a smartphone-based application to assist them.

Introduction. In an age where social media is prevalent and long hours are spent browsing through the internet, it is crucial to understand audience engagement. Two of the most common platforms used worldwide are Twitter and Facebook. Both have provided a unique opportunity for the science world; it broadened the horizons for spreading information on current endeavors in the research world. Clinical Neurophysiology and Clinical Neurophysiology Practice, the Official Journals of the International Federation of Clinical Neurophysiology, opened the Twitter and Facebook pages on April 1, 2020. We determined what factors would alter users’ engagement. Methods. We employed a multivariate regression analysis. The tested predictor variables included ‘days elapsed since the opening (range: 1–100)’, ‘posting during weekend’, ‘introduction of a 2020 article’, ‘author interview’, ‘inclusion of guidelines or review article’, ‘COVID19-related information’, ‘number of hashtags’, ‘number of attachments’, ‘presence of colored attachment’, and ‘attachment of movie’. The dependent variable was the proportion of engaged users, defined as the number of link clicks divided by users who saw the post. Results. Posts including author interviews (p Conversely, posts including a larger number of colored attachments (p Conclusion. Different types of posts attracted Facebook and Twitter users. Facebook users were specifically engaged with interview-based posts. Facebook users might be willing to read through lengthy posts to understand the authors’ stories behind the study. In contrast, Twitter users might want to absorb essential information with a glance.

Objective We aimed to redefine various periodic patterns (PPs) observed on electroencephalography (EEG) in patients with sporadic Creutzfeldt–Jakob disease (sCJD) using the American Clinical Neurophysiology Society's (ACNS) Criteria. Methods We analyzed EEG data of 23 patients with sCJD were admitted to two university hospitals between August 2005 and September 2015. Results We classified PPs on EEG data into three types: irregular periodic discharges (PDs) with superimposed rhythmic activities, appearing at a median of 8weeks after onset (w.a.o.); rhythmic sharp-and-wave, at a median of 11w.a.o.; and PDs with biphasic or triphasic morphology, at a median of 17w.a.o. Of 16 patients presenting with PPs, 14 had widespread lesions in both cortical and subcortical areas with clinical stage III at admission, and shorter time intervals for admission to hospital from disease onset than patients without PPs (Patients with PP, 11.6±12.2weeks; without PP, 18.2±8.3weeks; p =0.033). Conclusions PPs largely presented as three types at different stages of disease progression, and patients who had PPs had more wide spread lesions and rapid disease progression. Significance Our redefinition of PPs demonstrated on EEG using the ACNS criteria may contribute to further understanding of the pathological mechanisms of sCJD, and PPs might be a predictive factor of a rapid sCJD progression.

Objective To describe the electrophysiological characteristics and pathophysiological significance of electrographic status epilepticus (ESE) after cardiac arrest and specifically compare patients with unequivocal ESE to patients with rhythmic or periodic borderline patterns defined as possible ESE. Methods Retrospective cohort study of consecutive patients treated with targeted temperature management and monitored with simplified continuous EEG. Patients with ESE were identified and electrographically characterised until 72 h after ESE start using the standardised terminology of the American Clinical Neurophysiology Society. Results ESE occurred in 41 of 127 patients and 22 fulfilled the criteria for unequivocal ESE, which typically appeared early and transiently. Three of the four survivors had unequivocal ESE, starting after rewarming from a continuous background. There were no differences between the groups of unequivocal ESE and possible ESE regarding outcome, neuron-specific enolase levels or prevalence of reported clinical convulsions. Conclusion ESE is common after cardiac arrest. The distinction between unequivocal and possible ESE patterns was not reflected by differences in clinical features or survival. Significance A favourable outcome is seen infrequently in patients with ESE, regardless of using strict or liberal ESE definitions.

© 2020 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved, In recent years an increased level of motor neuronal excitation has been proposed as important in the neuronal degeneration so characteristic of amyotrophic lateral sclerosis (ALS/MND) (Van Den Bosch et al., 2006). This notion derives from the finding that levels of glutamate, an excitatory neurotransmitter, are raised in the cerebrospinal fluid in about 20% of patients with ALS/MND (Plaitakis and Caroscio, 1987) and glutamate transport is abnormal in brain and spinal cord tissue at autopsy (Rothstein et al., 1992; Yamanaka and Komine, 2018). Further, measurements of short interval cortical inhibition (SICI) in ALS/MND, using a threshold tracking protocol involving paired pulse transcranial magnetic stimulation of motor cortex, have shown that increased cortical excitability, determined by reduced cortical inhibition, may precede the clinical onset of ALS, and that this becomes more marked as the disease progresses (Vucic et al., 2008; Shibuya et al., 2017).

Objective To evaluate the prognostic value of single EEG patterns recorded at various time-frames in postanoxic comatose patients. Methods This retrospective study included 30-min EEGs, classified according to the definitions of continuity of background activity given by the American Clinical Neurophysiology Society. Isoelectric pattern was distinguished from other suppressed activities. Epileptiform patterns were considered separately. Outcome was dichotomised based on recovery of consciousness as good (Glasgow Outcome Scale [GOS] 3–5) or poor (GOS 1–2). Results We analysed 211 EEGs, categorised according to time since cardiac arrest (within 12 h and around 24, 48 and 72 h). In each time-frame we observed at least one EEG pattern which was 100% specific to poor or good outcome: at 12 h continuous and nearly continuous patterns predicted good outcome and isoelectric pattern poor outcome; at 24 h isoelectric and burst-suppression predicted poor outcome; at 48 and 72 h isoelectric, burst-suppression and suppression (2–10 μV) patterns predicted poor outcome. Conclusions The prognostic value of single EEG patterns, defined according to continuity and voltage of background activity, changes until 48–72 h after cardiac arrest and in each time-frame there is at least one pattern which accurately predicts good or poor outcome. Significance Standard EEG can provide time-dependent reliable indicators of good and poor outcome throughout the first 48–72 h after cardiac arrest.

EEG is widely used to predict outcome in comatose cardiac arrest patients, but its value has been limited by lack of a uniform classification. We used the EEG terminology proposed by the American Clinical Neurophysiology Society (ACNS) to assess interrater variability in a cohort of cardiac arrest patients included in the Target Temperature Management trial. The main objective was to evaluate if malignant EEG-patterns could reliably be identified. Full-length EEGs from 103 comatose cardiac arrest patients were interpreted by four EEG-specialists with different nationalities who were blinded for patient outcome. Percent agreement and kappa (κ) for the categories in the ACNS EEG terminology and for prespecified malignant EEG-patterns were calculated. There was substantial interrater agreement (κ 0.71) for highly malignant patterns and moderate agreement (κ 0.42) for malignant patterns. Substantial agreement was found for malignant periodic or rhythmic patterns (κ 0.72) while agreement for identifying an unreactive EEG was fair (κ 0.26). The ACNS EEG terminology can be used to identify highly malignant EEG-patterns in post cardiac arrest patients in an international context with high reliability. The establishment of strict criteria with high transferability between interpreters will increase the usefulness of routine EEG to assess neurological prognosis after cardiac arrest

Evaluation of the severity of diabetic polyneuropathy (DPN) is recommended according to Baba’s criteria (Baba M, Japanese Journal of Clinical Neurophysiology 2013). It is mainly studied in type 2 diabetes mellitus (DM). We examined whether these are also compatible with type 1 DM. Thirty-eight patients with type 1 DM were enrolled (21 female, mean age 59.6 ± 13.8 yo, mean clinical course 16.2 ± 9.4 years, mean HbA1c 7.8 ± 1.3%) and were compared with forty-two patients with type 2 DM. Nerve conduction studies of tibial and sural nerves were examined. All the patients with type 2 DM were applicable to Baba’s criteria. However, seven type 1 patients (18%) were not applicable. They disclosed abnormally small amplitude of sural nerve action potential, while the conduction velocity and minimum F wave latency of the tibial nerve were normal. Compound muscle action potentials of this nerve were normal as well. Among these seven patients, six showed the decreased Achilles tendon reflex, while it was preserved in the type 1 patients who showed similar conduction velocities and minimum F latency of the tibial nerve. These results suggest the different mechanism contribute to the pathophysiology between type 1 and type 2 DM, leading to sensory dominant axonal polyneuropathy without motor involvement in about 20% of patients with type1 DM.

Introduction Brain fingerprinting is a forensic science technique that uses electroencephalography (EEG) to determine whether specific information is stored in a subject’s brain. It does this by measuring electrical brainwave responses to pictures that are presented on a computer screen; P300 wave is a specific event-related potential (ERP) component that has the potential for detecting concealed information in the brain. Objectives: this work aimed to evaluate the appearance of P 300 wave in response to relevant visual stimuli and its absence to irrelevant ones and to evaluate the latency and amplitude of P300 wave in response to well-known persons and places. Methods This is a cross sectional prospective study carried out on 225 normal individuals at Clinical Neurophysiology Unit, Faculty of Medicine, Cairo University. It comprised both sexes aged from 18 to 70 years old; participants were divided into 3 groups. An endogenous ERP;P300 wave was seen evoked in response to rare, presented, recognized, meaningful stimulus, the peak amplitude was calculated and peak latency was measured from the time of stimulus onset. Results A photo of a person or place known to the test subject elicited a well-marked P300 response, while that of an unknown personality or place didn’t generate noticeable response. P300 wave latency and amplitude was recorded. There was a significant association between P300 amplitude and latency with age and educational level. Conclusion P300 wave is valuable in detecting concealed knowledge stored in the participant’s brain and is an objective and reliable test.

Introduction We recently showed that the EEG at 12 and 24 h after cardiac arrest reliably predicts the outcome of postanoxic coma. In this study, we investigate whether outcome predictions could be further improved by adding unfavorable EEG categories, and by evaluation of the EEG at other time points in the first five days after cardiac arrest. We validate our findings in a larger cohort, with patients recruited from three additional centers. Methods Data were collected in a prospective cohort study conducted at intensive care units of five hospitals in the Netherlands, between 2010 and 2017. In all comatose survivors of cardiac arrest, continuous EEG recordings were started as soon as possible and continued up to five days. Five-minute EEG epochs at 6, 12, 24, 36, 48, 72, 96, and 120 h after cardiac arrest were assessed by two independent reviewers, blinded for patients’ outcome. EEG classification was based on the American Clinical Neurophysiology Society’s standardized critical care EEG terminology. Patterns were categorized as favorable (continuous or nearly continuous background, with normal voltage) or unfavorable (burst-suppression with identical bursts or generalized periodic discharges (GPDs) on a suppressed background). A suppressed EEG (voltage μ V) at 12 h or later, and a low-voltage EEG (10–20 μ V) at 24 h or later, were also considered unfavorable. Outcome at 6 months after cardiac arrest was categorized as good (Cerebral Performance Category (CPC) 1–2) or poor (CPC 3–5). Results At time of submission of this abstract, data from two participating sites (Medisch Spectrum Twente, Rijnstate) have been analyzed. In these centers, 569 patients were included, of which 46% had a good outcome. The best timing to predict either a good or poor outcome was 12 h after cardiac arrest. A favorable EEG at 12 h predicted good outcome with a sensitivity of 0.46 (95% confidence interval (CI): 0.38–0.54) at a specificity of 0.90 (95%-CI: 0.85–0.94). At 24 h or later, specificity for the prediction of good outcome dropped below 0.90. At any of the investigated time points, an unfavorable EEG pattern predicted poor outcome without false positives. At 12 h, sensitivity reached its maximum value of 0.45 (95%-CI: 0.37–0.52) at specificity of 1.00 (95%-CI: 0.98–1.00) and dropped below 0.30 at 36 h or later. Conclusion We confirm that relevant discrimination for the prediction of good outcome after cardiac arrest with EEG is only possible up to 12 h after the event. Poor outcome can be predicted reliably up to five days, but sensitivity decreases significantly after the first 24 h. As compared to previous work, the addition of a suppressed EEG at 12 h and GPDs on a suppressed background at any time as unfavorable patterns increases sensitivity for the prediction of poor outcome. We will validate our findings on data from an additional 250 patients, recruited at the other three sites, and present these results at the ICCN 2018.

Introduction Neurophysiology is a young discipline in Morocco. The first department of Neurophysiology was created in 2003 in Rabat. It is the fruit of the collaboration of the various factors of neurosciences as well clinical as fundamental. The objective of this study is to describe the evolution of clinical neurophysiology and its future prospects within the International Federation of Neurophysiology. Methods The first department of neurology in Morocco was created in 1978 by two doctors trained in hospitals in France. This unit dedicated to neurological diseases was established at the University Hospital of Rabat, the first teaching university hospital in Morocco. Currently, there are 160 qualified neurologists in Morocco. Indeed, for clinical neurophysiology as an independent department of neurology, started in 2003 in Rabat. This department was followed by the creation of another service within the Rabat University Military Teaching Hospital. Some hospitals integrate neurophysiological explorations in a department of general clinical explorations as in Fez, while others keep them attached to neurology services “Marrakech, Oujda, Casablanca …”. Results The Clinical Neurophysiology Service in Rabat has two EEG video rooms, two EEG rooms, two EMG rooms and one EP room. The military structure also has a study unit for sleep disorders. Many programs, besides routine activities, have taken place. Thanks to the contacts maintained with the Executive Committee of the International Federation of Clinical Neurophysiology at the International Congress of Clinical Neurophysiology in Berlin in 2014, an Association named “MOROCCAN SOCIETY OF NEUROPHYSIOLOGY” non-profit organization in accordance with the provisions of the Moroccan law was created with a seat based in the city of Marrakech where the first Moroccan congress of neurophysiology was held in 2016 and the second jointly with the First African Congress and MENA of clinical neurophysiology in Rabat in 2017, without taking into account the practical workshops of ENMG and in EEG. Conclusion The future of the SMNP crystallizes from its main objectives: Participate in the promotion of neurophysiology, Establish links of mutual aid, friendship and exchange of experience between its members and finally contribute to the improvement the exercise of neurophysiological techniques whether in the experimental or clinical field in Morocco. Achieving these goals will continually require the support of the International Federation of Neurophysiology.

Background The central nervous system in chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is involved in about 5% of patients. The aim of the study was the assessment of the prevalence of central sensory impairment, and its reliance on peripheral nerve damage in patients with CIDP. Materials and methods The study group consisted of 24 patients with mean age of 60.7, who fulfilled the diagnostic criteria of typical form of CIDP at the time of multimodal (visual - VEP, brainstem auditory - BAEP, somatosensory SEP) evoked potentials (EPs) study. Each patient underwent a neurological examination, as well as a CT/MRI scan of the head. The evoked potentials was conducted according to the International Federation of Clinical Neurophysiology (IFCN) guidelines. Results Mean latency of most components of EP were considerably prolonged in patients compared to the control group. Negative correlations of SNAP amplitudes and sensory conduction velocities in peripheral nerves were obtained for I-V and III-V inter-latencies BAEP, for N20, P16, P22 SEP and the central conduction time TT for all sensory fibers of the left upper limb nerves. Conclusions Correlations of SNAP and EP parameters indicate subclinical damage to the central sensory pathways. The CIDP pathomechanism is still unclear and needs further research.

Background Presence of Epileptiform Discharges (ED) in EEG recordings are highly associated with an epilepsy diagnosis. The International Federation of Clinical Neurophysiology (IFCN) suggested 6 criteria in EEG sensor-space, so that presence of at least 4 of them defines a waveform as ED. The aim of our study to assess inter-rater agreement (IRA) and accuracy of identifying spikes in sensor space (using the IFCN criteria at different thresholds) and in source space. Methods EEG samples from 100 consecutive patients with epilepsy and non-epileptic paroxysmal events were reviewed separately in sensor-space and source-space, in different, randomized order, by 7 raters, who scored the presence/absence of each IFCN-criterion in sensor-space, and presence/absence of EDs in source-space. EDs were defined in sensor-space using different thresholds (2–6 criteria) and without counting criteria. Accuracy was determined for each rater and for the majority decisions for each sample. Material and results IRA was moderate both in sensor space and in source space (k: 0.49–0.60). In sensor-space, the highest accuracy (91%) and sensitivity (96%) was achieved using a threshold of 4 criteria. However, this gave a specificity that was lower than acceptable for EEG (85%). Using a threshold of 5 criteria in sensor-space specificity of 96% was achieved, at a sensitivity of 83% and accuracy of 89%. Results in source-space were identical to using the threshold of 5 criteria in sensor-space. Conclusions Using a threshold of 5 IFCN-criteria in sensor-space, and using source-space yields a high specificity and acceptable sensitivity for identifying EDs.

Background Use of transcranial magnetic stimulation (TMS) in clinical neurophysiology has expanded as navigated TMS and repetitive TMS therapies have gained popularity. Clinical applications and scientific studies often apply adaptive threshold hunting (ATH) to determine motor threshold (MT). MT expresses corticospinal excitability, and it is used as a baseline stimulation intensity (SI) for modulatory, therapeutic and mapping procedures. Currently available tools for ATH are system-integrated tools and stand-alone software. System-integrated tools are rare, and the available stand-alone software require a dedicated computer adding to laboratory space-requirements. Material and methods I programmed an Android-based “bestPEST” mobile application for ATH to allow for a simple recording of MTs with sharing capabilities and logging. The application applies parameter estimation by sequential testing and was named after Pentlands BestPEST-routine ( Pentland , 1980 ). The application is free through Google Play. For comparison I applied Motor Threshold Assessment Tool 2.0 ( Awiszus and Borckardt, 2012 ) as a reference method. I used data gathered from 15 healthy volunteers to simulate realistic motor evoked potentials (MEPs) utilizing random generator which considered the experimentally measured individual mean MEP amplitude and variation at different SIs ( Kallioniemi et al., 2018 ). Results The MTs of the different methods agreed well (ICC ⩾ 0.989, p Conclusions The bestPEST application produced similar MTs with the reference method, and will help investigators to determine MTs and to log results.