Continuous video-EEG Research Articles

Long-term EEG in adults: Sleep-deprived EEG (SDE), ambulatory EEG (Amb-EEG) and long-term video-EEG recording (LTVER)

Long-term EEG in adults includes three modalities: sleep deprived-EEG lasting 1 to 3 hours, 24 hours ambulatory-EEG and continuous prolonged video-EEG lasting from several hours to several days. The main indications of long-term EEG are: syndromic classification of epilepsy; search for interictal discharges when epilepsy is suspected or for the purpose of therapeutic evaluation; positive diagnosis of paroxysmal clinical events; and pre-surgical evaluation of drug-resistant epilepsy. Sleep deprived-EEG and ambulatory-EEG are indicated to detect interictal discharges in order to validate a syndromic classification of epilepsy when standard EEG is negative. These exams can help in evaluating treatment efficacy, especially when clinical evaluation is difficult. Long-term video EEG is indicated for drug-resistant epilepsy, to analyze electro-clinical correlations in a pre-surgical evaluation context, and to refine a positive diagnosis when paroxysmal clinical events are frequent.

Dystonic hyperkinesias in children of early childhood

Dystonic hyperkinesias in children of early childhood may be involved in the structure of many syndromes that have different etiological factors, prognosis, and treatment. This review presents various clinical types of dystonias: benign idiopathic forms of dystonia with onset in the first year of life, dystonic syndromes associated with residual damage to the nervous system, hereditary idiopathic dystonias, symptomatic dystonias, and also some similar conditions. Diagnosing of dystonia in children requires the use of a wide range of examinations, including neuroimaging, continuous video EEG monitoring, and genetic studies. The differential diagnosis of dystonias in children is carried out with different paroxysmal conditions of childhood that can be of epileptic and non-epileptic nature.

Efficacy of Continuous video EEG monitoring in the neurocritical care

Efficacy of Continuous video EEG monitoring in the neurocritical care

Nonconvulsive status epilepticus in the elderly associated with newer antidepressants used at therapeutic doses: A report of three cases.

Classic antidepressants have been known to induce convulsive seizures and nonconvulsive status epilepticus (NCSE). On the other hand, many reports have emphasized the safety of novel antidepressants. However, we encountered three cases of NCSE in the elderly associated with the use of newer antidepressants at therapeutic doses.All three patients were male and were 73 years of age or older. One patient was recently diagnosed with temporal lobe epilepsy and treated with low-dose lamotrigine. In all patients, newer antidepressants were initiated because of depressive symptoms. After titrating to therapeutic doses (paroxetine 20 mg/day, sertraline 50 mg/day, and combination of sertraline 50 mg/day and mirtazapine 30 mg/day in one patient each), impaired consciousness appeared. Electroencephalography (EEG) showed generalized slow waves with intermittent spike–slow-wave complexes. Intravenous injection of antiepileptic drugs improved EEG findings and clinical symptoms. After discontinuance of the abovementioned antidepressants, NCSE did not recur in any of patients. These reports raise the question of whether the newer antidepressants, like classic antidepressants, might also induce NCSE in the elderly, even when used at therapeutic doses. Physicians should consider monitoring for possible NCSE when using newer antidepressants in patients who may have low drug tolerability. Active continuous video-EEG monitoring is essential when behavioral and psychological symptoms or change in consciousness level is suspected.

The influence of staffing on diagnostic yield of EMU admissions: A comparison study between two institutions

Patients with recurrent, stereotyped neurological events of unclear etiology often warrant admission for continuous video-EEG monitoring in an epilepsy monitoring unit (EMU) for diagnosis. Epilepsy monitoring unit admission duration has been reported to range from days to weeks. To date, there are limited data on the average duration of admission for patients admitted to the EMU for spell classification. Many EMUs are forced to limit the overall duration of admission for numerous reasons including limited resources. It is unclear if a time-limited EMU stay reduces the event capture rate and, therefore, diagnostic yield of event classification admissions. The goal of this study was to determine how a time-limited length of stay strategy impacted event capture in patients admitted for spell classification. A retrospective chart review was performed at two comparable adult epilepsy monitoring units, Mayo Clinic Hospital (MCH) in Phoenix, Arizona, and Banner Good Samaritan Medical Center (BGSMC) in Phoenix, Arizona. Banner Good Samaritan Medical Center is only staffed Monday through Friday, thereby limiting the total possible duration of admission to five days. The goal was to determine if the rate of event capture differed between two institutions employing a time-limited EMU admission (BGSMC) when compared with the nonlimited admission (MCH). A total of 300 patient admissions at MCH and 260 patient admissions at BGSMC were reviewed over a comparable time period. The event capture rates at MCH and BGSMC were 74% and 72%, respectively. There was a greater percentage of patients with nonepileptic events (NEEs) at MCH than at BGSMC (62.7% vs. 47.3%). The mean duration until first event was 31h at MCH and 38h at BGSMC. The mean length of stay was greater at MCH (4.5days) when compared with BGSMC (3.3days). The overall diagnostic yield of a time-limited EMU admission was similar to that of a nonlimited admission for the purpose of spell classification. There was a statistically significant difference when comparing the time until first event at both institutions; however, this still fell within the 5-day duration that the time-restricted admission was limited to. These results may be important in optimizing an EMU practice in patients requiring admission for spell classification.

Variable electrobehavioral patterns during focal nonconvulsive status epilepticus induced by unilateral intrahippocampal injection of kainic acid.

Nonconvulsive status epilepticus (ncSE) is a severe condition that may result in neurologic sequelae and epilepsy resistant to pharmacologic treatment. We analyze here seizure and electroencephalography (EEG) patterns and their correlation to the development of a chronic epileptic condition in a guinea pig model of focal ncSE induced by intrahippocampal injection of kainic acid (KA). Electrobehavioral patterns during ncSE induced by unilateral injection of 1μg of KA in the CA1 region of the hippocampus were characterized by continuous video-EEG monitoring in 13 guinea pigs bilaterally implanted with recording electrodes in the hippocampus and neocortex. Video-EEG analysis demonstrates a high variability of seizure type and duration during KA-induced ncSE. Seizures showed focal signs correlated with diverse epileptiform EEG discharge distributions, either diffuse or localized. Nonfocal (bilateral motor) signs during seizures most likely correlated with a diffuse EEG pattern. The evolution into a chronic epileptic condition correlated neither with the severity of seizure pattern nor with the diffusion of the EEG discharges observed during the ncSE. Video-EEG monitoring in a guinea pig model of ncSE induced by unilateral hippocampal injection of KA demonstrates a high variability of electrobehavioral patterns. We demonstrate that the seizure severity score during focal ncSE is not a predictor of the evolution into a chronic epileptic condition of mesial temporal lobe epilepsy.

Early postnatal EEG features of perinatal arterial ischaemic stroke with seizures.

BackgroundStroke is the second most common cause of seizures in term neonates and is associated with abnormal long-term neurodevelopmental outcome in some cases.ObjectiveTo aid diagnosis earlier in the postnatal period, our aim was to describe the characteristic EEG patterns in term neonates with perinatal arterial ischaemic stroke (PAIS) seizures.DesignRetrospective observational study.PatientsNeonates >37 weeks born between 2003 and 2011 in two hospitals.MethodContinuous multichannel video-EEG was used to analyze the background patterns and characteristics of seizures. Each EEG was assessed for continuity, symmetry, characteristic features and sleep cycling; morphology of electrographic seizures was also examined. Each seizure was categorized as electrographic-only or electroclinical; the percentage of seizure events for each seizure type was also summarized.ResultsNine neonates with PAIS seizures and EEG monitoring were identified. While EEG continuity was present in all cases, the background pattern showed suppression over the infarcted side; this was quite marked (>50% amplitude reduction) when the lesion was large. Characteristic unilateral bursts of theta activity with sharp or spike waves intermixed were seen in all cases. Sleep cycling was generally present but was more disturbed over the infarcted side. Seizures demonstrated a characteristic pattern; focal sharp waves/spike-polyspikes were seen at frequency of 1–2 Hz and phase reversal over the central region was common. Electrographic-only seizure events were more frequent compared to electroclinical seizure events (78 vs 22%).ConclusionsFocal electrographic and electroclinical seizures with ipsilateral suppression of the background activity and focal sharp waves are strong indicators of PAIS. Approximately 80% of seizure events were the result of clinically unsuspected seizures in neonates with PAIS. Prolonged and continuous multichannel video-EEG monitoring is advocated for adequate seizure surveillance.

Integration of EEG lead placement templates into traditional technologist-based staffing models reduces costs in continuous video-EEG monitoring service.

The purpose of this study was to determine the relative cost reductions within different staffing models for continuous video-electroencephalography (cvEEG) service by introducing a template system for 10/20 lead application. We compared six staffing models using decision tree modeling based on historical service line utilization data from the cvEEG service at our center. Templates were integrated into technologist-based service lines in six different ways. The six models studied were templates for all studies, templates for intensive care unit (ICU) studies, templates for on-call studies, templates for studies of ≤ 24-hour duration, technologists for on-call studies, and technologists for all studies. Cost was linearly related to the study volume for all models with the "templates for all" model incurring the lowest cost. The "technologists for all" model carried the greatest cost. Direct cost comparison shows that any introduction of templates results in cost savings, with the templates being used for patients located in the ICU being the second most cost efficient and the most practical of the combined models to implement. Cost difference between the highest and lowest cost models under the base case produced an annual estimated savings of $267,574. Implementation of the ICU template model at our institution under base case conditions would result in a $205,230 savings over our current "technologist for all" model. Any implementation of templates into a technologist-based cvEEG service line results in cost savings, with the most significant annual savings coming from using the templates for all studies, but the most practical implementation approach with the second highest cost reduction being the template used in the ICU. The lowered costs determined in this work suggest that a template-based cvEEG service could be supported at smaller centers with significantly reduced costs and could allow for broader use of cvEEG patient monitoring.

Risk factors for EEG seizures in neonates treated with hypothermia

To assess the risk factors for electrographic seizures among neonates treated with therapeutic hypothermia for hypoxic-ischemic encephalopathy (HIE). Three-center observational cohort study of 90 term neonates treated with hypothermia, monitored with continuous video-EEG (cEEG) within the first day of life (median age at onset of recording 9.5 hours, interquartile range 6.3-14.5), and continued for >24 hours (total recording 93.3 hours, interquartile range 80.1-112.8 among survivors). A pediatric electroencephalographer at each site reviewed cEEGs for electrographic seizures and initial EEG background category. A total of 43 (48%) had electrographic seizures, including 9 (10%) with electrographic status epilepticus. Abnormal initial EEG background classification (excessively discontinuous, depressed and undifferentiated, burst suppression, or extremely low voltage), but not clinical variables (including pH <6.8, base excess ≤-20, or 10-minute Apgar ≤ 3), was strongly associated with seizures. Electrographic seizures are common among neonates with HIE undergoing hypothermia and are difficult to predict based on clinical features. These results justify the recommendation for cEEG monitoring in neonates treated with hypothermia.

Refractory Status Epilepticus: Experience in a Neurological Intensive Care Unit

Introduction. Refractory status epilepticus (RSE) has significant morbidity and mortality, and its management requires an accurate diagnosis and aggressive treatment. Objectives. To describe the experience of management of RSE in a neurological intensive care unit (NeuroICU) and determine predictors of short-term clinical outcome. Methods. We reviewed cases of RSE from September 2007 to December 2008. Management was titrated to findings on continuous video EEG (cVEEG). We collected patients’ demographics, RSE etiology, characteristics of seizures, cVEEG findings, treatments, and short-term outcome. Control of RSE was to achieve burst suppression pattern or electrographic cessation of ictal activity. Results. We included 80 patients; 63.8% were in coma, 25% had subclinical seizures, and 11.3% had focal activity. 51.3% were male and mean age was 45 years. Etiology was neurological lesion in 75.1%, uncontrolled epilepsy in 20%, and systemic derangements in 4.9%. 78.8% were treated with general anesthesia and concomitant anticonvulsant drugs. The control of RSE was 87.5% of patients. In-hospital mortality was 22.5%. The factors associated with unfavorable short-term outcome were coma and age over 60 years. Conclusions. RSE management guided by cVEEG is associated with a good seizure control. A multidisciplinary approach can help achieve a better short-term functional outcome in noncomatose patients.

Factitious psychogenic nonepileptic paroxysmal episodes.

Mistaking psychogenic nonepileptic paroxysmal episodes (PNEPEs) for epileptic seizures (ES) is potentially dangerous, and certain features should alert physicians to a possible PNEPE diagnosis. Psychogenic nonepileptic paroxysmal episodes due to factitious seizures carry particularly high risks of morbidity or mortality from nonindicated emergency treatment and, often, high costs in wasted medical treatment expenditures. We report a case of a 28-year-old man with PNEPEs that were misdiagnosed as ES. The patient had been on four antiseizure medications (ASMs) with therapeutic serum levels and had had multiple intubations in the past for uncontrolled episodes. He had no episodes for two days of continuous video-EEG monitoring. He then disconnected his EEG cables and had an episode of generalized stiffening and cyanosis, followed by jerking and profuse bleeding from the mouth. The manifestations were unusually similar to those of ES, except that he was clearly startled by spraying water on his face, while he was stiff in all extremities and unresponsive. There were indications that he had sucked blood from his central venous catheter to expel through his mouth during his PNEPEs while consciously holding his breath. Normal video-EEG monitoring; the patient's volitional and deceptive acts to fabricate the appearance of illness, despite pain and personal endangerment; and the absence of reward other than remaining in a sick role were all consistent with a diagnosis of factitious disorder.

KCNQ2 encephalopathy: Delineation of the electroclinical phenotype and treatment response

Neonatal-onset epilepsies are rare conditions, mostly genetically determined, that can have a benign or severe phenotype.(1,2) There is recent recognition of de novo KCNQ2 mutations in patients with severe neonatal-onset epilepsy with intractable seizures and severe psychomotor impairment, termed KCNQ2 encephalopathy.(3,4) This is a rare condition and all patients reported so far were diagnosed well after the neonatal period.(3,4) We report on 3 new cases of KCNQ2 encephalopathy diagnosed in the neonatal period and studied with continuous video-EEG recording. We describe a distinct electroclinical phenotype and report on efficacy of antiepileptic drug (AED) therapies.

Auditory hallucinations as ictal phenomena in a patient with voltage‐gated potassium channel antibody‐associated limbic encephalitis

Limbic encephalitis involving anti-voltage-gated potassium channel antibodies (VGKC-LE) has become increasingly recognised, with seizures and psychotic features, such as hallucinations being typical clinical manifestations. Though the literature supports auditory hallucinations as ictal phenomena, there are no reported cases of these hallucinations correlating with electrographic seizure for this disease entity. Early recognition of auditory hallucinations as seizures could alter treatment and subsequently affect short-term outcomes in these patients. We report the case of a patient with auditory hallucinations and progressive cognitive decline, as well as serological evidence of VGKC antibodies, in whom ictal hallucinations were identified by continuous video-EEG monitoring. This case highlights the subtlety of this entity, in both clinical and electrographic detection. [Published with video sequences].

Subclinical Posttraumatic Seizures Detected by Continuous Video-EEG Monitoring

Investigators at Mattel Children's Hospital, UCLA, and University of Colorado, used continuous video-EEG monitoring (cEEG) to study the incidence and risk factors for subclinical early posttraumatic seizures (EPTS) in 87 consecutive, unselected (mild – severe), acute traumatic brain injury (TBI) patients requiring admission to the PICU.

Multimodal presurgical evaluation in children with focal cortical dysplasia

WCN 2013 No: 1499 Topic: 1 — Epilepsy Pharmacologic and genetic aspects of resistant epilepsy in children in Uzbekistan N.M. Tuychibaeva, M.I. Sigatullina, A.V. Prokhorova. Tashkent Medical Academy, Uzbekistan; Tashkent Institute of Postgraduate of Medical Education, Tashkent, Uzbekistan Objectives: To develop methods of detection for the frequency and influence of polymorphism of cytochrome Р450 genes on pharmacologic and genetic action of antiepileptic drugs (AED). Identify the role of these genetic markers in individual responses to AED and development of pharmacologic resistance in epileptic patients. Material and methods: The research is based on studying the results of treatment of patients (n= 20)with resistant epilepsy. The control group included 25 volunteers of Uzbek nationality adjusted by sex and age. Results and conclusions: 1. Minimum level of gene variety of marker CYP2C9 in children was determined with not very high frequency of heterozygosis. Reduction of frequency of heterozygote genotype, absence of adverse genotype Т/Т and simultaneous increase in the share of individuals with normal homozygous С/С genotype among apparently healthy patients can be related to selective advantage of C allele. 2. Frequency of CYP2C9 polymorphism in pharmacoresistant patients considerably exceeded that in the control group indicating the association between development of resistance to AED and the genetic marker. The obtained statistically insignificant difference is most likely caused by the small amount of patients in the groups. 3. The genotypic variant distribution analysis of polymorphic marker 9896 C-G of CYP2E1 gene showed that among patients with the resistant epilepsy and the controls, the share of people with mutant genotypes had almost identical frequencies (20%). The risk of development of resistance to AED in carriers of the genotype was statistically insignificant (N0.05). doi:10.1016/j.jns.2013.07.103 Abstract — WCN 2013 No: 1513 Topic: 1 — Epilepsy Symptomatic versus idiopathic temporal lobe epilepsies: Findings from a cohort of 75 patients Y. Hizem, A. Nasri, M. Ben Djebara, Y. Sidhom, I. Abdelkefi, A. Gargouri-Berrechid, R. Gouider. Department of Neurology/Research Unit 03/UR/08-09, Research Unit 12SP21, Razi Hospital, Tunis, Tunisia Introduction: Temporal lobe epilepsy (TLE) is the most common form of focal epilepsy. Twomain varieties have been described in TLE: mesial and lateral or neocortical temporal epilepsy. Objective: To determine clinical, electrical and radiological differences between mesial and neocortical variants of temporal lobe epilepsies in idiopathic versus symptomatic groups. Methods: Retrospective study of clinical, electrical and radiological features in four groups: mesial symptomatic (MSTLE), neocortical symptomatic (NSTLE), mesial idiopathic (MITLE) and neocortical idiopathic (NITLE). Results: Total of 75 patients: 24 MSTLE, 33 NSTLE, 14 MITLE and 4 NITLE. The mean age of onset was respectively: 11.54, 22.63, 9.78 and 15.7 years. History of febrile seizures is found in 66% inMSTLE. Themain types of seizures are automatisms and visceral sensory auras in MTLE symptomatic (75% and 58% respectively) and idiopathic (43% and 71% respectively). Psychic auras are the most frequent type in NSTLE (42%) and language alterations in NITLE (100%). spike-waves are common in mesial group. Pharmaco-resistance is more frequent in MSTLE (54%) and NITLE (50%). In the symptomatic group, brain MRI shows association of other temporal lobe abnormalities to mesial sclerosis in 46%. Conclusion: Our study shows earlier age of onset with a higher frequency of febrile seizures and pharmaco-resistance in MSTLE group. The Symptomatic group of TLE is characterized by older age and higher frequency of background EEG abnormalities. Some features are shared between the symptomatic or idiopathic variants and others depend on the mesial or neocortical localization. doi:10.1016/j.jns.2013.07.104 Abstract — WCN 2013 No: 1511 Topic: 1 — Epilepsy Multimodal presurgical evaluation in children with focal cortical dysplasia WCN 2013 No: 1511 Topic: 1 — Epilepsy Multimodal presurgical evaluation in children with focal cortical dysplasia M. Sigatullina, G. Garcia, J. Muchart, M. Rebollo, J. Aparicio, F. Sanmarti. Epilepsy Unit, University Hospital Sant Joan de Deu, Barcelona, Spain Objective: To evaluate the effectiveness of multimodal presurgical evaluation in patients with focal cortical dysplasia (FCD). Methods and subjects:We performed preand postsurgical evaluation in 20 patients withmalformations of cortical development (MCD) aged from 2 months till 17 years old. All of them underwent continuous video-EEG, MRI, 18 FDG-PET and SISCOM investigations. Results: There were operated 20 patients with MCD with preand postsurgical evaluation. Themean age at neurosurgerywas 6.5 years. 18 patients had different types FCD and 2 had hemimegalencephaly. The mean period between epilepsy onset and neurosurgery was 6 years. In 15 (75%) patients the presurgical MRI (1.5 T) detected FCD correlated with focal rhythmic epileptiform discharges during video-EEG register. In 5 patients (25%) with negative MRI, 18 FDG-PET and SISCOM were useful to complete the preoperative study. Surgical procedures included 6 temporal, 10 extratemporal, 2 multilobar resections and 2 functional hemispherotomies. Brain histological analysis confirmed the diagnosis ofMCD in all cases. The outcome after 1 year of neurosurgery, according Abstracts / Journal of the Neurological Sciences 333 (2013) e1–e64 e27

Subclinical early posttraumatic seizures detected by continuous EEG monitoring in a consecutive pediatric cohort

Traumatic brain injury (TBI) is an important cause of morbidity and mortality in children, and early posttraumatic seizures (EPTS) are a contributing factor to ongoing acute damage. Continuous video-EEG monitoring (cEEG) was utilized to assess the burden of clinical and electrographic EPTS. Eighty-seven consecutive, unselected (mild - severe), acute TBI patients requiring pediatric intensive care unit (PICU) admission at two academic centers were monitored prospectively with cEEG per established clinical TBI protocols. Clinical and subclinical seizures and status epilepticus (SE, clinical and subclinical) were assessed for their relation to clinical risk factors and short-term outcome measures. Of all patients, 42.5% (37/87) had seizures. Younger age (p = 0.002) and injury mechanism (abusive head trauma - AHT, p < 0.001) were significant risk factors. Subclinical seizures occurred in 16.1% (14/87), while 6.9% (6/87) had only subclinical seizures. Risk factors for subclinical seizures included younger age (p < 0.001), AHT (p < 0.001), and intraaxial bleed (p < 0.001). SE occurred in 18.4% (16/87) with risk factors including younger age (p < 0.001), AHT (p < 0.001), and intraaxial bleed (p = 0.002). Subclinical SE was detected in 13.8% (12/87) with significant risk factors including younger age (p < 0.001), AHT (p = 0.001), and intraaxial bleed (p = 0.004). Subclinical seizures were associated with lower discharge King's Outcome Scale for Childhood Head Injury (KOSCHI) score (p = 0.002). SE and subclinical SE were associated with increased hospital length of stay (p = 0.017 and p = 0.041, respectively) and lower hospital discharge KOSCHI (p = 0.007 and p = 0.040, respectively). cEEG monitoring significantly improves detection of seizures/SE and is the only way to detect subclinical seizures/SE. cEEG may be indicated after pediatric TBI, particularly in younger children, AHT cases, and those with intraaxial blood on computerized tomography (CT).

Pediatric Seizures

On the basis of strong evidence, treatment is highly dependent on the seizure semiology results, electroencephalography (EEG) findings, and origin. • On the basis of moderate evidence and consensus, vigorous use of video EEG recordings and home video cameras should be used to delineate the epileptic syndromes. • On the basis of strong evidence, pediatric epilepsy syndromes have common comorbidities. As a consensus, some pediatric epilepsy centers consider referral to a neuropsychologist to be first-line care in these patients. • On the basis of strong evidence and consensus, antiepileptic drug therapy has its own complications and should be discontinued after an appropriate treatment course. • On the basis of moderate evidence and consensus, uncontrolled seizures put patients at risk for significant morbidity and mortality.

The contribution of voxel-based morphometry in the detection of cortical dysplasia in patients with PET positive MR negative epilepsy

Methods. We evaluated prospectively 596 patients with pharmacoresistant seizures. All these patients underwent continuous video-EEG monitoring. In consenting patients, we used suggestive seizure provocation. The seizure semiology, inter-ictal EEG, brain MRI, psychiatric co-morbidities, and the impact of the provocative testing and other parameters on the seizure outcome were assesed. Results. In the sample of 596 monitored patients, we detected 111 (19.3%) patients with PNES. Of the 111 patients with PNES, 86.5% had spontaneous and 76.5% had provoked seizures. The five most typical symptoms – initially closed eyelids (67.6%), rapid tremor (47.7%), asynchronous limb movement (37.8%), preictal pseudosleep (33.3%), and side-to-side head movement (32.4%) – were presented on video. Inter-ictal EEG was rated as abnormal in 46.2% and with epileptiform abnormality in 9%. Brain MRI was abnormal in 32 (28.8%) patients. Personality disorders (46.8%), anxiety (39.6%), and depression (12.6%) were the most frequent additional psychiatric co-morbidities. Psychogenic non-epileptic seizures outcome after at least 2 years is reported; 22.5% of the patients were seizure-free; one third had markedly reduced seizure frequency. The provocative testing had no negative impact on the seizure outcome. We determined eight variables which could affect the seizure outcome. The trend to be the predictor of worse results was PNES duration before appropriate diagnosis (pb0.013). Conclusions. Video-EEG monitoring with suggestive seizure provocation supported by clinical psychiatric and psychological evaluations sig

4. ICU EEG study

Prolonged EEG monitoring in the ICU is now common. Studies suggest that the prevalence of seizures and nonconvulsive status epilepticus (NCSE) is 10% or more. However, the selection criteria for monitoring remain ambiguous, and the impact of prolonged EEG monitoring on treatment is unclear. We addressed these questions by performing prolonged EEG on patients for whom a routine 30-min or prolonged EEG was requested by ICU staff. During a prospective but not randomized 22-month study, EEGs were requested by ICU staff on 130 patients, with diagnoses of trauma, tumor, stroke, metabolic derangement, cerebral hemorrhage, and hypoxic–ischemic injury. Patients were placed in three groups. Group 1 : 34 patients received a 30-min EEG, because for various reasons long-term recording could not be done. Group 2 : 83 patients for whom staff requested a 30-min EEG, instead received 16–24 h of continuous video-EEG monitoring. Group 3 : 13 patients, with known epilepsy, for whom continuous video-EEG monitoring was requested, received 16–24 h of recording to monitor suspected status epilepticus. Epileptologists compared the first 30 min of EEG with the subsequent recording to see if any additional information was obtained, and if it impacted treatment. Group 1: 34 patients had a routine 30-min EEG. One was normal, 27 were slow or poorly reactive, and six (18%) showed epileptiform activity, including one with electrographic seizures. Group 2: 83 patients were monitored with video-EEG for 16–24 h. All EEGs were abnormal with slowing and poor reactivity. 28/83 patients (34%) showed epileptiform findings in the first 30 min, including periodic epileptiform discharges (PEDs), generalized or focal epileptiform discharges, burst suppression, triphasic waves, and 2 patients had clinical seizures. 5/28 developed additional epileptiform changes overnight, including two more with clinical seizures. 55/83 patients (66%) had no epileptiform findings in the first 30 min, but 7/55 developed these overnight, including two with electrographic and one with clinical seizures. Overall, in 12/83 patients additional epileptiform abnormalities developed overnight, and in 7/83 treatment was changed based on prolonged as opposed to routine EEG. 3/7 patients in whom treatment was changed showed improvement. Group 3: 13 patients known to have epilepsy, who presented with seizures, were deliberately placed on long term video-EEG monitor. 9/13 (69%) showed epileptiform abnormalities in the first 30 min including three with NCSE and one with focal seizures. Overnight two more evolved into NCSE, and prolonged EEG influenced therapy in 6/13. In 83 unselected ICU patients, overnight video-EEG, as opposed to a 30-min EEG, detected additional epileptiform abnormalities in 12 patients (14%), and 7/83 patients (8%) had changes in treatment based on findings from prolonged as opposed to routine EEG. In contrast, patients with epilepsy who presented with seizures were more likely than other ICU patients to have NCSE, and prolonged EEG influenced treatment in 6/13 (46%). This study suggests that long-term EEG monitoring in an unselected ICU population rarely influences treatment or outcome. In a selected population with known epilepsy the benefit may be larger.

Rapamycin Attenuates the Development of Posttraumatic Epilepsy in a Mouse Model of Traumatic Brain Injury

Posttraumatic epilepsy is a major source of disability following traumatic brain injury (TBI) and a common cause of medically-intractable epilepsy. Previous attempts to prevent the development of posttraumatic epilepsy with treatments administered immediately following TBI have failed. Recently, the mammalian target of rapamycin complex 1 (mTORC1) pathway has been implicated in mechanisms of epileptogenesis and the mTORC1 inhibitor, rapamycin, has been proposed to have antiepileptogenic effects in preventing some types of epilepsy. In this study, we have tested the hypothesis that rapamycin has antiepileptogenic actions in preventing the development of posttraumatic epilepsy in an animal model of TBI. A detailed characterization of posttraumatic epilepsy in the mouse controlled cortical impact model was first performed using continuous video-EEG monitoring for 16 weeks following TBI. Controlled cortical impact injury caused immediate hyperactivation of the mTORC1 pathway lasting at least one week, which was reversed by rapamycin treatment. Rapamycin decreased neuronal degeneration and mossy fiber sprouting, although the effect on mossy fiber sprouting was reversible after stopping rapamycin and did not directly correlate with inhibition of epileptogenesis. Most posttraumatic seizures occurred greater than 10 weeks after TBI, and rapamycin treatment for one month after TBI decreased the seizure frequency and rate of developing posttraumatic epilepsy during the entire 16 week monitoring session. These results suggest that rapamycin may represent a rational treatment for preventing posttraumatic epilepsy in patients with TBI.