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SUMMARYObjective: Evaluate the seizure-reduction response and safety of mesial temporal lobe (MTL) brain-responsive stimulation in adults with medically intractable partial-onset seizures of mesial temporal lobe origin. Methods: Subjects with mesial temporal lobe epilepsy (MTLE) were identified from prospective clinical trials of a brain-responsive neurostimulator (RNS System, NeuroPace). The seizure reduction over years 2-6 postimplantation was calculated by assessing the seizure frequency compared to a preimplantation baseline. Safety was assessed based on reported adverse events. Results: There were 111 subjects with MTLE; 72% of subjects had bilateral MTL onsets and 28% had unilateral onsets. Subjects had one to four leads placed; only two leads could be connected to the device. Seventy-six subjects had depth leads only, 29 had both depth and strip leads, and 6 had only strip leads. The mean follow-up was 6.1 AE (standard deviation) 2.2 years. The median percent seizure reduction was 70% (last observation carried forward). Twenty-nine percent of subjects experienced at least one seizure-free period of 6 months or longer, and 15% experienced at least one seizure-free period of 1 year or longer. There was no difference in seizure reduction in subjects with and without mesial temporal sclerosis (MTS), bilateral MTL onsets, prior resection, prior intracranial monitoring, and prior vagus nerve stimulation. In addition, seizure reduction was not dependent on the location of depth leads relative to the hippocampus. The most frequent serious device-related adverse event was soft tissue implant-site infection (overall rate, including events categorized as device-related, uncertain, or not device-related: 0.03 per implant year, which is not greater than with other neurostimulation devices). Significance: Brain-responsive stimulation represents a safe and effective treatment option for patients with medically intractable epilepsy, including patients with unilateral or bilateral MTLE who are not candidates for temporal lobectomy or who have failed a prior MTL resection.

Summary:Purpose: When seizures do not respond to medications, video-EEG monitoring is the best available diagnostic tool and is the principal activity of epilepsy centers. The purpose of this study was to analyze the eventual disposition of patients who undergo video-EEG monitoring at a typical referral epilepsy center.Methods: We reviewed the diagnoses and dispositions of all patients (adults and children) who underwent inpatient video-EEG monitoring (≥24 h) at our center (University of South Florida-Tampa General Hospital) over a 1-year period (2002).Results: In total, 251 inpatient video-EEG monitoring sessions were performed. Nonepileptic seizures were diagnosed in 75 (30%); 58 (23%) were found to be surgical candidates; seven were implanted with the vagus nerve stimulator. In 47 (19%) patients, seizures were recorded, and the diagnosis of epilepsy was confirmed and clarified (symptomatic/cryptogenic generalized epilepsy, seven; localization-related epilepsy, 35; idiopathic generalized epilepsy, five). Conclusions:The eventual outcome of video-EEG monitoring is diverse. The largest groups, as expected, are psychogenic nonepileptic seizures (30%), and surgery (23%). Key Words: Video-EEG-Psychogenic-Nonepileptic seizure.Epilepsy affects 1% of the population, and ∼20 to 30% of patients with epilepsy are medically intractable (1,2). This means that the prevalence of medically intractable epilepsy is ∼0.2 to 0.3%, comparable to the overall prevalence of multiple sclerosis. For patients whose seizures do not respond to medications, video-EEG monitoring is the best available diagnostic tool and the starting point to evaluate treatment options (1). Video-EEG monitoring allows (a) making a diagnosis of epilepsy versus nonepileptic events; (b) correctly diagnosing the seizure type and epilepsy syndrome; and (c) if the seizures are focal, localizing the area of seizure onset. As a result, it is then possible to examine therapeutic options (1). Thus video-EEG monitoring is the principal activity of epilepsy centers.The purpose of this study was to describe the eventual disposition of patients who undergo video-EEG monitoring at a typical referral epilepsy center.

SUMMARYObjective: Evaluate the seizure-reduction response and safety of brain-responsive stimulation in adults with medically intractable partial-onset seizures of neocortical origin. Methods: Patients with partial seizures of neocortical origin were identified from prospective clinical trials of a brain-responsive neurostimulator (RNS System, NeuroPace). The seizure reduction over years 2-6 postimplantation was calculated by assessing the seizure frequency compared to a preimplantation baseline. Safety was assessed based on reported adverse events. Additional analyses considered safety and seizure reduction according to lobe and functional area (e.g., eloquent cortex) of seizure onset. Results: There were 126 patients with seizures of neocortical onset. The average followup was 6.1 implant years. The median percent seizure reduction was 70% in patients with frontal and parietal seizure onsets, 58% in those with temporal neocortical onsets, and 51% in those with multilobar onsets (last observation carried forward [LOCF] analysis). Twenty-six percent of patients experienced at least one seizure-free period of 6 months or longer and 14% experienced at least one seizure-free period of 1 year or longer. Patients with lesions on magnetic resonance imaging (MRI; 77% reduction, LOCF) and those with normal MRI findings (45% reduction, LOCF) benefitted, although the treatment response was more robust in patients with an MRI lesion (p = 0.02, generalized estimating equation [GEE]). There were no differences in the seizure reduction in patients with and without prior epilepsy surgery or vagus nerve stimulation. Stimulation parameters used for treatment did not cause acute or chronic neurologic deficits, even in eloquent cortical areas. The rates of infection (0.017 per patient implant year) and perioperative hemorrhage (0.8%) were not greater than with other neurostimulation devices. Significance: Brain-responsive stimulation represents a safe and effective treatment option for patients with medically intractable epilepsy, including adults with seizures of neocortical onset, and those with onsets from eloquent cortex.

The proportion of patients with psychogenic nonepileptic seizures (PNES) who also have epilepsy has been reported to vary from 10% to over 50%. The authors reviewed all 32 patients diagnosed with PNES in our EEG-video monitoring unit over a period of 1 year, and only 3 (9.4%) had interictal epileptiform discharges to support a coexisting diagnosis of epilepsy. Thus, the authors believe that only a small proportion of patients with PNES have coexisting epilepsy.

The overinterpretation of EEGs is a known problem that has not been reported specifically. The authors report a series of EEGs on patients who were diagnosed eventually with psychogenic nonepileptic seizures and who had an EEG read as epileptiform. Of the 15 actual records available for review, the overread patterns were wicket spikes (n = 1), hypnagogic hypersynchrony (n = 1), and hyperventilation-induced slowing (n = 1). In the other 12 records, the overread patterns were simple fluctuations of sharply contoured background rhythms or fragmented alpha activity. Rather than well-described normal variants, the overinterpreted patterns tend to be normal fluctuations of background activity.

IMPORTANCE Misdiagnosis of epilepsy is common. Video electroencephalogram provides a definitive diagnosis but is impractical for many patients referred for evaluation of epilepsy.OBJECTIVE To evaluate the accuracy of outpatient smartphone videos in epilepsy. DESIGN, SETTING, AND PARTICIPANTSThis prospective, masked, diagnostic accuracy study (the OSmartViE study) took place between August 31, 2015, and August 31, 2018, at 8 academic epilepsy centers in the United States and included a convenience sample of 44 nonconsecutive outpatients who volunteered a smartphone video during evaluation and subsequently underwent video electroencephalogram monitoring. Three epileptologists uploaded videos for physicians from the 8 epilepsy centers to review. MAIN OUTCOMES AND MEASURES Measures of performance (accuracy, sensitivity, specificity, positive predictive value, and negative predictive value) for smartphone video-based diagnosis by experts and trainees (the index test) were compared with those for history and physical examination and video electroencephalogram monitoring (the reference standard). RESULTS Forty-four eligible epilepsy clinic outpatients (31 women [70.5%]; mean [range] age, 45.1 [20-82] years) submitted smartphone videos (530 total physician reviews). Final video electroencephalogram diagnoses included 11 epileptic seizures, 30 psychogenic nonepileptic attacks, and 3 physiologic nonepileptic events. Expert interpretation of a smartphone video was accurate in predicting a video electroencephalogram monitoring diagnosis of epileptic seizures 89.1% (95% CI, 84.2%-92.9%) of the time, with a specificity of 93.3% (95% CI, 88.3%-96.6%). Resident responses were less accurate for all metrics involving epileptic seizures and psychogenic nonepileptic attacks, despite greater confidence. Motor signs during events increased accuracy. One-fourth of the smartphone videos were correctly diagnosed by 100% of the reviewing physicians, composed solely of psychogenic attacks. When histories and physical examination results were combined with smartphone videos, correct diagnoses rose from 78.6% to 95.2%. The odds of receiving a correct diagnosis were 5.45 times greater using smartphone video alongside patient history and physical examination results than with history and physical examination alone (95% CI, 1.01-54.3; P = .02). CONCLUSIONS AND RELEVANCEOutpatient smartphone video review by experts has predictive and additive value for diagnosing epileptic seizures. Smartphone videos may reliably aid psychogenic nonepileptic attacks diagnosis for some people.

The concept of epilepsy syndromes, introduced in 1989, was defined as “clusters of signs and symptoms customarily occurring together”. Definition of epilepsy syndromes based on electro‐clinical features facilitated clinical practice and, whenever possible, clinical research in homogeneous groups of patients with epilepsies. Progress in the fields of neuroimaging and genetics made it rapidly clear that, although crucial, the electro‐clinical description of epilepsy syndromes was not sufficient to allow much needed development of targeted therapies and a better understanding of the underlying pathophysiological mechanisms of seizures. The 2017 ILAE position paper on Classification of the Epilepsies recognized that “as a critical tool for the practicing clinician, epilepsy classification must be relevant and dynamic to changes in thinking”. The concept of “epilepsy syndromes” evolved, incorporating issues related to aetiologies and comorbidities. A comprehensive update (and revision where necessary) of the EEG diagnostic criteria in the light of the 2017 revised terminology and concepts was deemed necessary. Part 2 covers the neonatal and paediatric syndromes in accordance with the age of onset. [Published with educational EEG plates at http://www.epilepticdisorders.com].