A critical appraisal on the utility of long-term video-EEG monitoring in older adults

Challenges and Prospects in Epilepsy Monitoring Units: A Comprehensive Review of Logistic Barriers

Epilepsy is one of the most common neurological diseases with a prevalence ranging from 0.5% to 2% in different sittings. The World Health Organization (WHO) estimated that nearly 80% of this burden is borne by resource-poor countries where even conventional electroencephalogram (EEG) coverage is dramatically short.  Video EEG monitoring applied for days as conducted in epilepsy monitoring units (EMUs) is aimed at seizure localization, anti-seizure medication (ASM) adjustment, or epilepsy surgery evaluation and planning. However, the EEG approach in EMUs has its obstacles. The present article is aimed to concentrate on the logistic challenges of EMUs, discussing existing data and limitations and offering suggestions for future planning to enhance the utilization of existing technology. Shortages of adult and pediatric epileptologists, qualified nurses, as well as EEG technologists have been reported in different countries. Moreover, injuries and falls, psychosis, status epilepticus, and unexpected death have been stated to be the most frequent safety issues in EMUs. Enhancements to mitigate logistical and healthcare system-related barriers in EMUs include the implementation of large cohort studies and the utilization of artificial intelligence (AI) for the identification and categorization of specific risks among EMU admissions. The establishment of EMUs and their associated challenges and barriers are best acknowledged through discussions and dialogue with various stakeholders.

Dual diagnosis of epilepsy and dissociative seizures: Prescription patterns, feasibility and safety of rationalising antiseizure medication

BACKGROUND

Patients with a dual-diagnosis of epilepsy and dissociative seizures (DS) have received far less attention than those with single pathology. Anti-seizure medication (ASM) prescription patterns and safety of rationalisation have not been reviewed.

METHODS

We undertook a retrospective cohort study of all patients with a dual-diagnosis admitted to the Scottish Epilepsy Centre between 2012-2020. ASM frequencies were compared across admission, discharge and follow-up and emergency hospital attendances compared a year before and after admission. Demographic data, seizure characteristics and mortality data were also reviewed.

RESULTS

Across the 139 patients included in our study, ASM frequency at follow-up was significantly lower than on admission (mean 2.51 vs 2.14, Z = -2.11 p = 0.035, r = -0.215). Total hospital attendances in the year following admission were significantly lower than in the year before (mean 1.27 vs 0.77, Z = 2.306, p = 0.021, r = -0.262). Those with inactive epilepsy had their medications reduced to a greater extent that those with active epilepsy. 44 patients had their ASM frequency reduced during admission with a similar trend of reduced hospital attendances (mean 1.29 vs 0.43 Z = -3.162 p = 0.002). There was one epilepsy related death.

CONCLUSIONS

Clinicians should consider the development of co-morbid DS in patients with epilepsy not responding to an escalation of ASM, especially if presenting with a new seizure type. Patients with a dual-diagnosis of epilepsy and DS, particularly those with well controlled epilepsy, are likely overtreated with ASM. Medication review in a tertiary epilepsy centre allows for safe rationalisation of ASM and likely contributes to the need for fewer hospital attendances.

Assessing 72 h vs. 24 h of long-term video-EEG monitoring to confirm the diagnosis of epilepsy: a retrospective observational study

Introduction

Paroxysmal seizure-like events can be a diagnostic challenge. Inpatient video-electroencephalography (EEG) monitoring (VEM) can be a valuable diagnostic tool, but recommendations for the minimal duration of VEM to confirm or rule out epilepsy are inconsistent. In this study, we aim to determine whether VEM of 48 or 72 h was superior to 24 h.

Methods

In this monocentric, retrospective study, we included 111 patients with paroxysmal, seizure-like events who underwent at least 72 h of VEM. Inclusion criteria were as follows: (1) Preliminary workup was inconclusive; (2) VEM admission occurred to confirm a diagnosis; (3) At discharge, the diagnosis of epilepsy was conclusively established. We analyzed the VEM recordings to determine the exact time point of the first occurrence of epileptic abnormalities (EAs; defined as interictal epileptiform discharges or electrographic seizures). Subgroup analyses were performed for epilepsy types and treatment status.

Results

In our study population, 69.4% (77/111) of patients displayed EAs during VEM. In this group, the first occurrence of EAs was observed within 24 h in 92.2% (71/77) of patients and within 24-72 h in 7.8% (6/77). There was no statistically significant difference in the incidence of EA between medicated and non-medicated patients or between focal, generalized epilepsies and epilepsies of unknown type. Of the 19 recorded spontaneous electroclinical seizures, 6 (31.6%) occurred after 24 h.

Discussion

A VEM of 24 h may be sufficient in the diagnostic workup of paroxysmal seizure-like events under most circumstances. Considering the few cases of first EA in the timeframe between 24 and 72 h, a prolonged VEM may be useful in cases with a high probability of epilepsy or where other strategies like sleep-EEG or ambulatory EEG show inconclusive results. Prolonged VEM increases the chance of recording spontaneous seizures. Our study also highlights a high share of subjects with epilepsy that do not exhibit EAs during 72 h of VEM.

Ambulantes Langzeit-Video-EEG als neuer diagnostischer Ansatz in Deutschland: Ergebnisse einer Machbarkeitsstudie

Das Langzeit-Video-EEG als Goldstandarddiagnostik bei Epilepsie und anderen Anfallsleiden ist in Deutschland derzeit nur in wenigen spezialisierten Zentren zur stationären Überwachung verfügbar. Diese begrenzten Überwachungskapazitäten und der damit verbundene hohe Zeit- und Arbeitsaufwand führen bundesweit zu einer erheblichen Wartezeit für diese wichtige Diagnostik. Neue, tragbare Sensortechnologien und automatisierte Datenanalysemethoden schaffen Möglichkeiten für Video-EEG-Langzeituntersuchungen nach dem Goldstandard im ambulanten Bereich, die dazu beitragen können, diese Barriere zu überwinden. Hier berichten wir über die Ergebnisse einer Machbarkeitsstudie an einem Zentrum, in der das ambulante Langzeit-Video-EEG (ALVEEG) als diagnostischer Weg in Deutschland eingeführt wurde. In dem neuen Diagnostikpfad soll der Einsatz innovativer, tragbarer Video-EEG-Monitoringsysteme zusammen mit einer durch künstliche Intelligenz unterstützten Datenanalyse den von Anfallsleiden betroffenen Patienten einen schnelleren, effizienteren und sektorübergreifenden Zugang zu einer Goldstandarddiagnostik in der häuslichen Umgebung ermöglichen. Die Diagnostik wurde von Patienten und Klinikern gut angenommen und könnte eine ergänzende Option zur stationären Überwachung darstellen, um die derzeitigen Engpässe in Diagnostik und Versorgung zu beseitigen.

Utilization of Epilepsy Monitoring Unit by General Neurologists

Background

Epilepsy monitoring unit (EMU) is a growing service that allows physicians to evaluate, diagnose, and manage epilepsy in a safe and cost-effective way. However, observations have indicated that the EMU is being underutilized by general neurology practice, possibly due to the lack of access and specific criteria known to all neurologists. There is limited data as of yet to support these observations. This study reviewed the rate of referral to the EMU from outpatient general neurology clinics at our institution.

Methods

In this retrospective study, records of 350 patients, 18 years or older with a diagnosis or diagnostic workup of epilepsy, managed by neurologists who did not specialize in epilepsy, were reviewed. We classified patients into three groups: ineligible for EMU referral, eligible and referred to EMU, and eligible but not referred to EMU based on six criteria namely characterization, classification, localization, determination of seizure frequency, medication adjustment, and differentiation between seizures and medication side effects.

Results

Our results demonstrated that 36.7% of patients who did meet the criteria were not referred to EMU. The most common criteria for patient referral in both groups, referred and not referred, was the characterization of seizures as epileptic or functional.

Conclusion

Our results show that EMU is underutilized by our general neurology clinics. Providing more information and increased awareness about criteria for long-term monitoring in EMU can improve the utility of this valuable tool and would be beneficial to patient care.

Minimum standards for inpatient long-term video-EEG monitoring: A clinical practice guideline of the international league against epilepsy and international federation of clinical neurophysiology

The objective of this clinical practice guideline is to provide recommendations on the indications and minimum standards for inpatient long-term video-electroencephalographic monitoring (LTVEM). The Working Group of the International League Against Epilepsy and the International Federation of Clinical Neurophysiology develop guidelines aligned with the Epilepsy Guidelines Task Force. We reviewed published evidence using The Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statement. We found limited high-level evidence aimed at specific aspects of diagnosis for LTVEM performed to evaluate patients with seizures and nonepileptic events (see Table S1). For classification of evidence, we used the Clinical Practice Guideline Process Manual of the American Academy of Neurology. We formulated recommendations for the indications, technical requirements, and essential practice elements of LTVEM to derive minimum standards used in the evaluation of patients with suspected epilepsy using GRADE (Grading of Recommendations, Assessment, Development, and Evaluation). Further research is needed to obtain evidence about long-term outcome effects of LTVEM and establish its clinical utility.

Minimum standards for inpatient long-term video-electroencephalographic monitoring: A clinical practice guideline of the International League Against Epilepsy and International Federation of Clinical Neurophysiology

The objective of this clinical practice guideline is to provide recommendations on the indications and minimum standards for inpatient long-term video-electroencephalographic monitoring (LTVEM). The Working Group of the International League Against Epilepsy and the International Federation of Clinical Neurophysiology develop guidelines aligned with the Epilepsy Guidelines Task Force. We reviewed published evidence using the PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analysis) statement. We found limited high-level evidence aimed at specific aspects of diagnosis for LTVEM performed to evaluate patients with seizures and nonepileptic events. For classification of evidence, we used the Clinical Practice Guideline Process Manual of the American Academy of Neurology. We formulated recommendations for the indications, technical requirements, and essential practice elements of LTVEM to derive minimum standards used in the evaluation of patients with suspected epilepsy using GRADE (Grading of Recommendations Assessment, Development, and Evaluation). Further research is needed to obtain evidence about long-term outcome effects of LTVEM and to establish its clinical utility.

Psychiatric and cognitive characteristics of older adults admitted to a Video-EEG monitoring (VEM) unit

OBJECTIVE

To compare the clinical, psychiatric, and cognitive characteristics of older with younger patients presenting to a video-EEG monitoring (VEM) unit.

METHOD

This was a retrospective case-control study involving patients admitted for VEM over a two-year period (from April 2018 to April 2020) at two comprehensive epilepsy units. Patients were categorized into an older (≥60 years) and a younger (<60 years) group. Younger patients were individually matched to older adults to form a matched younger group. Diagnosis was determined by a consensus opinion of epileptologists, neurologists, and neuropsychiatrists. The main diagnostic categories were epilepsy, psychogenic nonepileptic seizures (PNES), and 'other' diagnosis (non-diagnostic and other nonepileptic diagnoses). Clinical psychiatric diagnoses were obtained from neuropsychiatric reports. Objective cognitive function was measured with the Neuropsychiatry Unit Cognitive Assessment Tool (NUCOG). Subjective cognitive function was assessed using the Quality of Life in Epilepsy Inventory-89 (QOLIE-89) cognitive subscales.

RESULTS

Five-hundred and thirty three patients (71 older, 462 younger) aged 16-91 years were admitted to the VEM unit during the study period. There was a diagnosis of focal epilepsy in 55% of the older group and 48% of the younger group, generalized epilepsy in 3% of the older group and 10% of the younger group, and 'other' in 32% of the older group and 19% of the younger group. Ten percent (2 males and 5 females) of the older group were diagnosed with PNES compared to 22% of the younger group (p = 0.016). A depressive disorder was diagnosed in 34% of the older group and 24% of the younger group (p = 0.20). An anxiety disorder was diagnosed in 15% of the older group and 25% of the younger group (p = 0.15). Mild neurocognitive disorder was more common in the older group (34%) compared to the matched younger group (34% vs 3%, p < 0.001). The older group had lower mean NUCOG scores compared to the matched younger group (79.49 vs 87.73, p = <0.001). There was no evidence for a relationship between mean NUCOG score and overall subjective cognitive difficulties for the older group (r = 0.03, p = 0.83). Among older adults, those diagnosed with PNES had more experiences of childhood trauma. Measures of dissociation, depression, or general anxiety did not differ between PNES and non-PNES diagnoses in the older group.

CONCLUSION

Psychiatric comorbidities are common among older adults admitted for VEM. The psychological impact of epilepsy and risk factors for PNES seen in younger patients are also applicable in the older group. The older group demonstrated more cognitive impairments than the younger group, although these were usually unrecognized by individuals. Older adults admitted to VEM will benefit from psychiatric and neuropsychological input to ensure a comprehensive care approach to evaluation and management.

Psychogenic Nonepileptic Seizures and Psychosocial Management: A Narrative Review

Psychogenic non-epileptic seizure (PNES) is a common disorder that imitates epileptic seizures and has its etiological roots in psychological distress. Due to its “epileptic” similarity, it is often dealt with not only by mental health professionals but also by physicians, pediatricians and neurologists. There is a growing consensus towards the psychotherapeutic treatment of the disorder, albeit a lack of clarity in choosing a gold-standard approach. This paper seeks to serve as a compendium of different psychotherapeutic approaches and their efficacy in the management of PNES. The paper employed the search strategy by selecting the keywords: “Psychogenic Non-Epileptic Seizures (PNES) and psychosocial management”, “PNES Treatment approach”, “PNES and psychotherapy” in PUBMED, EBSCO host, PsycINFO, and SCOPUS database. Eventually, specific therapies were cross-searched with PNES for an exhaustive review. Several studies were found employing various psychotherapeutic approaches for the treatment of PNES in pilot studies, randomized controlled, or open uncontrolled trials. Cognitive Behavior Therapy was demonstrated as an efficacious treatment for PNES in a randomized controlled trial (RCT). Other approaches that were effective in ameliorating the symptoms were psychodynamic therapies or psychoeducation based group therapies. Some therapies like Novel Integrative psychotherapy, Eye Movement Desensitisation Therapy and Mindfulness-based therapies require further exploration in larger clinical trials. The findings demonstrate that psychological intervention for PNES is a promising alternative treatment approach with a need for more RCTs with a larger sample and robust methodology for better generalization.

[The problem of comorbidity of epilepsy and psychogenic paroxysms]

A review of publications over the last two decades is presented. Psychogenic paroxysms develop in approximately 12% of patients with epilepsy. The analysis of social and demographic data, history details, semiological features and results of electrophysiological and neuroimaging studies does not unequivocally support the comorbidity of epilepsy and psychogenic paroxysms. The pathogenetic mechanisms of the development of comorbidity are various and depend on the presence of pharmacoresistance, psychological traumas in the past, intellectual disability etc. Video-EEG-monitoring is the gold standard in the diagnosis of comorbidity of epilepsy and psychogenic paroxysms. Treatment of such cases includes anticonvulsants and cognitive-behavioral therapy.

Clinical characteristics of video-EEG patients: Limited utility of prolonging VEEG study duration beyond 5 days for spell classification

OBJECTIVE

The objective of the study was to identify the probability of establishing a diagnosis based on the duration of video-electroencephalogram (VEEG) monitoring. Additional aims were to determine whether there is a relationship between clinical characteristics of epilepsy monitoring unit (EMU) patients and VEEG results.

METHODS

We studied EMU length of stay and assessed the utility of prolonging studies in patients who had not yet received a diagnosis. Clinical characteristics in 212 consecutive patients admitted for scalp VEEG monitoring were recorded. We collected data including reason for admission, frequency of seizures/spells, gender, age, age at seizure onset, handedness, family history, history of neurologic disease, current and past antiepileptic drugs (AEDs), and prior work-up. Subjects were categorized into five diagnostic groups: epileptic seizures (Epi), nonepileptic events (NEE), mixed epileptic and nonepileptic events (Mixed), nonepileptic events from a physiologic cause (NEEP), and nondiagnostic study without results recorded (ND).

RESULTS

The most diagnoses were made during the first day of admission (45%), and by day 3, 82 patients remained without a diagnosis. On day 3, 25 of these patients (33%) received a diagnosis, on day 4, seven (22%) additional patients received a diagnosis, on day 5, 5 patients (35%) received a diagnosis, and by day 6, only one additional patient (11%) was given a diagnosis. Significant differences were found between diagnostic groups for admission reason, duration of EMU stay, age at seizure onset, duration of epilepsy, seizure frequency, and number of current and previously tried AEDs.

CONCLUSIONS

Our findings show that the majority of patients are diagnosed in the first 2 days of admission, and we found a limited benefit of prolonging nonsurgical inpatient VEEG studies beyond 5 days for spell/seizure classification. Additionally, patient demographics were significantly different for patients depending on VEEG diagnosis, which can help predict the utility of completing VEEG studies in individual patients.

Latencies to first interictal epileptiform discharges in different seizure types during video-EEG monitoring

PURPOSE

Interictal epileptiform discharges (IEDs) have high diagnostic value concerning patients with epilepsy and the instances of obtaining IEDs increase with longer recording times. However, the merit of a single, extended electroencephalography (EEG) recording in detecting IEDs has not been substantiated. We aimed to determine the optimal duration of an EEG required to diagnose epilepsy in different seizure types.

METHODS

Overall, 84 patients-29 with generalised onset epilepsy and 55 with focal onset epilepsy-were evaluated. Long-term video electroencephalographic monitoring (VEM) was analysed to find the first definite IED besides assessing the first seizure and latency.

RESULTS

The median latency of the first IED (12 min, ranging from 1 to 440 min vs. 55 min, ranging from 2 to 7500 min; p =  0.014) and the median duration of a VEM recording (2 d, ranging from 1 to 10 d vs. 3 d, ranging from 1 to 10 d; p =  0.012) were found significantly lower in the generalised epilepsy group compared with that in the focal epilepsy group.

CONCLUSIONS

Generalised onset epilepsy showed a significantly shorter latency to IED and VEM duration compared with focal onset epilepsy. In our data set, all the patients with generalised onset epilepsy had interictal IED within 10 h, but the patients with focal onset epilepsy required monitoring for three days to obtain IED.

Dual diagnosis of epilepsy and psychogenic nonepileptic seizures: Systematic review and meta-analysis of frequency, correlates, and outcomes

Comorbid epilepsy and psychogenic nonepileptic seizures (PNES) represent a serious challenge for the clinicians. However, the frequency, associations, and outcomes of dual diagnosis of epilepsy and PNES are unclear. The aim of the review was to determine the frequency, correlates, and outcomes of a dual diagnosis. A systematic review of all published observational studies (from inception to Dec. 2016) was conducted to determine the frequency, correlates, and outcomes of dual diagnosis. We included studies of individuals of any age reporting a dual diagnosis of epilepsy and PNES. All observational study designs were included with the exception of case reports and case series with fewer than 10 participants. The mean frequency of epilepsy in patients with PNES across all studies was 22% (95% confidence intervals [CI] 20 to 25%, range: 0% to 90%) while the mean frequency of PNES in patients with epilepsy was 12% (95% CI 10 to 14%, range: 1% to 62%). High heterogeneity means that these pooled estimates should be viewed with caution. A number of correlates of dual diagnosis were reported. Some studies delineated differences in semiology of seizures in patients with dual diagnosis vs. PNES or epilepsy only. However, most of the correlates were inconclusive. Only a few studies examined outcome in patients with dual diagnosis. Dual diagnosis is common in clinical practice, especially among patients referred to specialized services, and requires careful diagnosis and management.

The Usefulness of Nap Sleep Recording During Routine Electroencephalography: An Audit Study

OBJECTIVES

A measure to increase the electroencephalogram (EEG) outcome includes a short period of nap sleep during a routine standard EEG with the aim of increasing its sensitivity to interictal abnormalities or provoking seizures. As part of an ongoing auditing of our EEG data, we aimed to investigate the contribution of nap sleep during routine outpatient department based EEGs requested for a variety of reasons.

METHODS

EEG data at the Department of Clinical Physiology at Sultan Qaboos University Hospital, Oman, from July 2006 to December 2007 and from January 2009 to December 2010 (total 42 months) were reviewed. The EEGs were for patients older than 13-years referred for possible epilepsy, blackouts, headache, head trauma, and other non-specified attacks. The recording period was between 20 to 40 minutes. Abnormalities were identified during waking and nap sleep periods.

RESULTS

A total of 2 547 EEGs were reviewed and 744 were abnormal (29.2%). Of those abnormal EEGs, nap sleep was obtained in 258 (34.7%) EEGs, and 39 (15.1%) showed abnormalities during nap sleep. Nineteen out of the 39 (48.7%) EEGs were abnormal during awake and nap sleep; and 20 (51.3%) were abnormal during nap sleep, which represented only 2.7% of the total abnormal EEGs (n = 744).

CONCLUSIONS

The contribution of the short nap sleep to the pickup rate of interictal abnormalities in EEG was minimal. We recommend the EEG service to include one cycle of spontaneous sleep EEG directed at patients with a history suggestive of epilepsy if their awake EEGs are normal.

Intracranial video-EEG monitoring in presurgical evaluation of patients with refractory epilepsy

OBJECTIVE

Reviewing our experience in intracranial video-EEG monitoring in the presurgical evaluation of patients with refractory epilepsy.

METHODS

We report on 62 out of 202 (31%) patients with refractory epilepsy, who underwent a long term video-EEG monitoring (LTM). The epileptogenic zone (EZ) was localised either based on the results of LTM or after intracranial EEG recordings from depth, subdural or foramen ovale electrodes. The decision on the location of the electrodes was based upon semiology of the seizures, EEG findings and the lesions visualised in MRI brain scan. Intraoperative corticography was carried out before and right after the resection of the seizure onset zone.

RESULTS

The video-EEG monitoring could localise EZ in 43 (69%) cases based. The remaining patients underwent invasive diagnostics: 10 (53%) had intracerebral depth electrodes, 6 (31%) depth and subdural and 3 (16%) foramen ovale electrodes. Intracranial video EEG recordings showed seizure focus in all the patients. Ten of them had EZ in mesial temporal structures, 4 in accessory motor area, 3 at the base of the frontal lobe and 2 in parietal lobe. There was one case of an asymptomatic intracerebral haematoma at the electrode. All patients were subsequently operated on. In 15 (79%) cases the seizures subsided (follow-up from 2 to 5 years), in 4 (21%) they decreased.

CONCLUSIONS

The intracranial EEG is required in all patients with normal MRI (so-called nonlesional cases) in whom EZ is suspected to be located in the hippocampus, insula or in the basal parts of the frontal lobe.

Evaluation of MEG vs EEG after sleep deprivation in epilepsy

OBJECTIVE

MEG and EEG after sleep deprivation (EEG-SD) are applied as diagnostic tools in the evaluation of patients with possible epilepsy. There is no gold standard to check whether the diagnosis based on these two modalities is correct. The best standard available is the long-term follow-up of patients. As follow-up of an earlier study in which the additional value of MEG vs EEG-SD diagnosis was evaluated, we investigated the long-term validity of MEG-based and EEG-SD-based diagnosis.

MATERIALS AND METHODS

Data collected from 46 patients were used in a comparative study of the last known diagnosis against the original one of 8 years ago.

RESULTS

Long-term (3-8 years) sensitivity of sharp phenomena (combining spikes and sharp waves) in routine MEG and in EEG-SD for the diagnosis epilepsy is 71% and 62%, respectively. When compared to the original study, this hardly changed. Over time, uncertainty on diagnosis diminishes.

CONCLUSION

MEG as well as EEG-SD are robust long-term predictors for epilepsy.

Optimal time of duration of a long-term video-EEG monitoring in paroxysmal events - A retrospective analysis of 282 sessions in 202 patients

PURPOSE

To find the optimal duration of the long-term video-EEG (LTM) and assess diagnostics utility of LTM in patients with epilepsy and other paroxysmal events in terms of future diagnosis and management.

METHODS

Retrospective analysis of 282 LTMs performed in the last 5 years in our Epilepsy Monitoring Unit (EMU), in 202 consecutive patients. The analysis included demographic data, monitoring time, number and type of paroxysmal events, the time until their onset, influence of LTM result on the diagnosis and future management.

RESULTS

There were 117 women and 85 men, mean age 34.2 years. Mean duration of LTM was 5 days (3-9), with 447 paroxysmal events recorded in 131 (65%) patients. Epileptic seizures were recorded in 82% cases (in 11% associated with PNES). The remaining 18% had either PNES (psychogenic non-epileptic seizures) - 11%, or parasomnias - 7%. Only 15% of epileptic seizures took place within the first 24h of the LTM (53% and 32% on the 2nd and 3rd day, respectively), whereas as many as 62% of PNES did (while only 28% and 10% on the 2nd and 3rd day, respectively). The LTM results changed the diagnosis in 36% of the patients, most frequently in PNES (from 2% to 14%). Altogether, it changed the management in 64% of the patients - particularly with PNES and those who underwent epilepsy surgery.

CONCLUSIONS

LTM should last at least 72h in patients with refractory epilepsy. Most of cases with PNES could be diagnosed after 48h.

[French guidelines on electroencephalogram]

Electroencephalography allows the functional analysis of electrical brain cortical activity and is the gold standard for analyzing electrophysiological processes involved in epilepsy but also in several other dysfunctions of the central nervous system. Morphological imaging yields complementary data, yet it cannot replace the essential functional analysis tool that is EEG. Furthermore, EEG has the great advantage of being non-invasive, easy to perform and allows control tests when follow-up is necessary, even at the patient's bedside. Faced with the advances in knowledge, techniques and indications, the Société de Neurophysiologie Clinique de Langue Française (SNCLF) and the Ligue Française Contre l'Épilepsie (LFCE) found it necessary to provide an update on EEG recommendations. This article will review the methodology applied to this work, refine the various topics detailed in the following chapters. It will go over the summary of recommendations for each of these chapters and underline proposals for writing an EEG report. Some questions could not be answered by the review of the literature; in those cases, an expert advice was given by the working and reading groups in addition to the guidelines.

Diagnostic yield of inpatient video-electroencephalographic monitoring: experience from a Chinese comprehensive epilepsy center

Video-electroencephalographic monitoring (VEEG) is useful in the diagnosis of seizure disorders; however, its diagnostic yield in developing countries is not well known. The current study retrospectively reviewed the charts of 484 consecutive patients who were admitted to our center between July 2012 and September 2013. Of these patients, 298 (61.6%) were admitted for diagnostic clarification and underwent VEEG for a mean duration of 1.3days (range=1-9days). The patients were divided into two groups: those whose diagnosis was changed and those whose diagnosis was not changed as a result of VEEG. A patient with a preadmission diagnosis of epilepsy who was discharged with a diagnosis of nonepileptic events (NEEs) or who was further classified as focal/generalized epilepsy on discharge was included in the "change in diagnosis" group. A patient admitted with an uncertain diagnosis and discharged with a diagnosis of NEEs or epilepsy (including focal epilepsy and generalized epilepsy) was also included in the "change in diagnosis" group. Video-electroencephalographic monitoring recorded typical ictal events (epileptic events or nonepileptic events) in 147 (49.3%) of the patients admitted for diagnostic clarification. In total, 181 (60.7%) patients had a change in diagnosis after VEEG. Among them, 103 (56.9%) patients had a preadmission diagnosis of epilepsy, which was further classified as focal epilepsy (88 patients) or generalized epilepsy (15 patients); the diagnosis of NEEs and epilepsy was clarified in 78 (43.1%) patients. The number of patients diagnosed with NEEs increased from 31 (10.4%) on admission to 88 (29.5%) on discharge. Among all the patients admitted for diagnostic clarification, therapeutic plans were changed for 104 (57.5%) patients. In 117 (39.3%) patients with no diagnostic change, VEEG evaluation provided confirmative diagnostic information in 47 (15.8%) patients and no additional diagnostic information in 70 (23.5%) patients. The study indicates that VEEG is useful in terms of clarifying seizure diagnoses and evaluating seizure frequency. In our cohort study, VEEG of a relatively short mean duration produced a comparable diagnostic yield as that reported in other studies.

Value analysis of continuous EEG in patients during therapeutic hypothermia after cardiac arrest

INTRODUCTION

Therapeutic hypothermia (TH) is standard of care after ventricular fibrillation cardiac arrest (CA). Continuous EEG monitoring (cEEG) is increasingly used during TH. Analysis regarding value of cEEG utilization in this population in the context of cost and outcome has not been performed. We compared outcome and EEG charges in CA patients with selective versus routine cEEG.

METHODS

A protocol for TH after CA without routine cEEG was implemented in December 2005, comprising our TH-pre-cEEG cohort. In November 2009, this protocol was changed to include cEEG in all CA-TH patients, comprising our TH-cEEG cohort. Clinical outcome using the Cerebral Performance Category (CPC) at discharge and estimated EEG charges were calculated retrospectively for both cohorts, based on National Charge Data 50th percentile charges expressed in USD per the CMS 2010 Standard Analytical File as reported in Code Correct by MedAssets, Inc.

RESULTS

Our TH-pre-cEEG cohort comprised 91 patients, our TH-cEEG cohort 62. In the TH-pre-cEEG cohort, 19 patients (21%) had rEEGs, 4 (4%) underwent cEEG. The mean estimated EEG charges for the TH-pre-cEEG cohort was $1571.59/patient, and TH-cEEG cohort was $4214.93/patient (p<0.0001). Two patients (2.1%) in the TH-pre-cEEG cohort had seizures, compared to five (8.1%) in the TH-cEEG cohort (p=0.088). There was no difference in mortality or clinical outcome in these cohorts.

CONCLUSIONS

Routine use of cEEG during TH after CA improved seizure detection, but not outcomes. There was a three-fold increase in EEG estimated charges with routine use of cEEG.

Epilepsy, unawareness of seizures and driving license: the potential role of 24-hour ambulatory EEG in defining seizure freedom

INTRODUCTION

Seizures represent a potential source of accidents/death. Permission to drive may, therefore, be granted in a seizure-free period. Laws and regulations regarding this issue vary widely, and the onus of reporting seizures ultimately rests on the individual. Unfortunately, as some patients are unaware of their seizures, their reports may be unreliable.

METHODS

In this retrospective study, we selected, from a group of 1100 consecutive patients, 57 cases (26 males/31 females; mean age: 42.5 years) in whom the AEEG documented ictal events (UIEs) not reported in a self-kept diary. By means of a simple questionnaire, we interviewed all these patients to collect information on driving licenses. We, thus, assessed how many of these patients (both drug resistant and seizure free) drove regularly.

RESULTS

Our study shows a relatively large number of patients with epilepsy and UIEs. Fifteen patients suffered from idiopathic generalized epilepsy (IGE) while 42 had partial epilepsy (PE). The patients were seizure free in 21 cases and 36 had drug-resistant seizures. Many patients in both these subgroups had a driving license and drove normally (active driving in 12/36 drug-resistant patients and in 18/21 seizure-free patients). Worthy of note is the finding that an "apparently" seizure-free group of patients drove regularly.

CONCLUSIONS

This study revealed a large number of patients (both drug resistant and seizure free) with AEEG-documented UIEs. This finding highlights the usefulness of AEEG in clinical practice as a means of more accurately ascertaining seizure freedom and supporting decisions involving the renewal or granting of a driving license.