Diagnostic decision-making after a first and recurrent seizure in adults

Purpose The role of EEG after a first seizure has been debated. Epileptiform EEG activity is a good predictor of seizure recurrence, but is reported in only 8-50% of first-seizure adult patients. Even if the EEG is abnormal, the opinions about treatment after a first seizure differ. The role of EEG in treatment decisions after remission or recurrence is also unclear. This study aims to identify neurologists' diagnostic strategies compared to guidelines about the use of EEG (i) after a first unprovoked generalized seizure in adults, (ii) after a recurrent seizure and (iii) in treatment decisions after recurrence or remission. Method All members of the Dutch Neurological Society were invited to participate in our on-line survey about the use of EEG after a first seizure, after recurrent seizures and in treatment decisions. Ten percent (N = 110) of invitees participated, including mainly clinical neurophysiologists, general neurologists and neurologists-in-training. Results Ninety-five percent of the respondents would request a routine EEG after a first seizure. After normal MRI and EEG findings, 4% would record a second routine EEG, 48% a sleep-deprived EEG and 45% would not repeat the EEG. If a recurrent seizure occurs within six, or after 12 or 24 months, 87%, 67% and 44% would respectively conclude that the patient has epilepsy, while 57%, 65% and 72% would request an EEG. When a patient experiences a recurrence while being treated with anti-epileptic drugs, 11% of the respondents would request an EEG. Twenty-five percent would request an EEG before stopping medication after two years of remission. Conclusion The variability in neurologists' reported strategies about the use of EEG in the diagnosis of seizures is remarkably large. Consequences for the individual patient may be significant, including treatment decisions and driving restrictions. The availability and use of more sensitive diagnostic methods may be necessary to enhance agreement between neurologists. © 2013 British Epilepsy Association

Inter-ictal spike detection using a database of smart templates

Objective: Visual analysis of EEG is time consuming and suffers from inter-observer variability. Assisted automated analysis helps by summarizing key aspects for the reviewer and providing consistent feedback. Our objective is to design an accurate and robust system for the detection of inter-ictal epileptiform discharges (IEDs) in scalp EEG. Methods: IED Templates are extracted from the raw data of an EEG training set. By construction, the templates are given the ability to learn by searching for other IEDs within the training set using a time-shifted correlation. True and false detections are remembered and classifiers are trained for improving future predictions. During detection, trained templates search for IEDs in the new EEG. Overlapping detections from all templates are grouped and form one IED. Certainty values are added based on the reliability of the templates involved. Results: For evaluation, 2160 templates were used on an evaluation dataset of 15 continuous recordings containing 241 IEDs (0.79/min). Sensitivities up to 0.99 (7.24 fp/min) were reached. To reduce false detections, higher certainty thresholds led to a mean sensitivity of 0.90 with 2.36 fp/min. Conclusion: By using many templates, this technique is less vulnerable to variations in spike morphology. A certainty value for each detection allows the system to present findings in a more efficient manner and simplifies the review process. Significance: Automated spike detection can assist in visual interpretation of the EEG which may lead to faster review times. © 2013 International Federation of Clinical Neurophysiology

Interpretation of Kappa values as suggested by [30].

<p>Interpretation of Kappa values as suggested by <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0085966#pone.0085966-Landis1" target="_blank">[30]</a>.</p

After visually reviewing the EEG in its raw form, participants were shown a quantitative EEG display which summarizes the entire recording into a single window.

<p>Using the report provided in this window (right), participants were asked to correct the automated interpretation where needed and afterwards upload the corrected reports for comparison.</p

Five questions were asked to each participant after all EEGs were reviewed.

<p>Five questions were asked to each participant after all EEGs were reviewed.</p

Outline of the study.

<p>For each of the 45 recordings, participants were asked to open the EEG in the conventional way (Fig. 2) and review five background properties by visual inspection. After this, they were asked to open a new window showing a summary of the quantitative features (Fig. 3), and to correct the mistakes made in a report generated by automated interpretation.</p

Theory of the interaction of planetary Nebulae with the interstellar medium

To appear in Asymmetrical Planetary Nebulae II: from Origins to Microstructures, '' ASP ConferenceConsiglio Nazionale delle Ricerche - Biblioteca Centrale - P.le Aldo Moro, 7 Rome / CNR - Consiglio Nazionale delle RichercheSIGLEITItal

Novel multipin electrode cap system for dry electroencephalography

Current usage of electroencephalography (EEG) is limited to laboratory environments. Self-application of a multichannel wet EEG caps is practically impossible, since the application of state-of-the-art wet EEG sensors requires trained laboratory staff. We propose a novel EEG cap system with multipin dry electrodes overcoming this problem. We describe the design of a novel 24-pin dry electrode made from polyurethane and coated with Ag/AgCl. A textile cap system holds 97 of these dry electrodes. An EEG study with 20 volunteers compares the 97-channel dry EEG cap with a conventional 128-channel wet EEG cap for resting state EEG, alpha activity, eye blink artifacts and checkerboard pattern reversal visual evoked potentials. All volunteers report a good cap fit and good wearing comfort. Average impedances are below 150 k Omega for 92 out of 97 dry electrodes, enabling recording with standard EEG amplifiers. No significant differences are observed between wet and dry power spectral densities for all EEG bands. No significant differences are observed between the wet and dry global field power time courses of visual evoked potentials. The 2D interpolated topographic maps show significant differences of 3.52 and 0.44 % of the map areas for the N75 and N145 VEP components, respectively. For the P100 component, no significant differences are observed. Dry multipin electrodes integrated in a textile EEG cap overcome the principle limitations of wet electrodes, allow rapid application of EEG multichannel caps by non-trained persons, and thus enable new fields of application for multichannel EEG acquisition.This work was financially supported by the German Federal Ministry of Education and Research (03IPT605A), the German Academic Exchange Service (D/57036536), the Thuringer Aufbaubank and the European Social Fund (2012 FGR 0014), and the European Union (FP7-PEOPLE Marie Curie IAPP project 610950).info:eu-repo/semantics/publishedVersio