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Background The insular cortex is an eloquent island of mesocortex surrounded by vital structures making this region relatively challenging to neurosurgeons. Historically, lesions in this region were considered too high risk to approach given the strong chance of poor surgical outcome. Advances in recent decades have meant that surgeons can more safely access this eloquent region. Seizure outcome after excision of insular low-grade gliomas is well reported, but little is known about seizure outcomes after excision of insular high-grade gliomas. Methods A retrospective analysis was performed of all patients presenting with new-onset seizures during 2015–2019 who underwent excision of an insular high-grade glioma at 3 regional neurosurgical centers in the United Kingdom. Results We identified 38 patients with a mean (SD) age of 45.7 (15.3) years with median follow-up of 21 months. At long-term follow-up, of 38 patients, 23 were seizure-free (Engel class I), 2 had improved seizures (Engel class II), 6 had poor seizure control (Engel class III/IV), and 7 died. Conclusions Excision of insular high-grade gliomas is safe and results in excellent postoperative seizure control.

Background Epileptic surgery is the potentially curative treatment for children with refractory seizures. The study aimed to quantify and analyze high frequency oscillation (HFO) ripples and interictal epileptiform discharges (EDs) in intraoperative electrocorticography (ECoG) between malformation of cortical dysplasia (MCD) and non-MCD children with MRI-lesional focal epilepsy, and evaluate of seizure outcomes after epileptic surgery. Methods The intraoperative ECoG was performed before and after lesionectomy. Quantifications of HFO ripples and interictal EDs of ECoG by frequency, amplitude, and foci of intraoperative ECoG were performed based on electrode location, and the characteristics of ECoG recordings were analyzed in each patient based on their histopathology. Seizure outcome after surgery according to their quantitative ECoG findings was analyzed. Results Frequency of EDs and HFO ripple rates in preresection ECoG were significantly higher in children with MCD compared with non-MCD (p = 0.018 and p = 0.002, respectively). Higher frequencies of EDs and ripple rates in preresection ECoG were observed in residual seizures than in seizure-free children (p = 0.045 and p = 0.005, respectively). Clinically, children with residual seizures after surgery were significantly younger at the onset, had a trend of higher seizure frequency and higher spike frequency of presurgical videoEEG. Conclusion Our results suggested that quantification of intraoperative ECoG predicted seizure outcomes and reflected different ED pattern and frequencies between MCD and non-dysplastic histopathology among children who underwent resective epileptic surgery. The results of our study were encouraging and indicated that intraoperative ECoG improved the outcomes of surgery in children with epilepsy.

Objective To determine whether semiological similarity of electrically induced seizures (EIS) and spontaneously occurring habitual seizures (SHS) is associated with postsurgical seizure outcome in patients undergoing invasive video-EEG monitoring (VEM) before resective epilepsy surgery. Methods Data of patients undergoing invasive VEM were retrospectively reviewed and included if at least one EIS and SHS during VEM occurred and the brain region in which EIS were elicited was resected. Seizure outcome was evaluated at three follow-up (FU) visits after surgery (1, 2 years and last available FU) according to the classification by Engel and the International League Against Epilepsy (ILAE). The level of semiological similarity of EIS and SHS was rated blinded to the surgical outcome. Statistics were done using Fisher’s exact test and a mixed linear-logistic regression model. Results 65 patients were included. Postsurgical seizure freedom was achieved in 51% (ILAE class 1) and 58% (Engel class I) at last FU (median 36 months). Patients with identical EIS and SHS displayed significantly better postsurgical seizure outcomes (ILAE class 1 at last FU: 76% vs. 31%, p Conclusion EIS are useful to confirm the location of the epileptogenic zone. A high level of similarity between EIS and SHS is associated with a favorable postsurgical seizure outcome. Significance EIS may be used as an additional predictor of postsurgical outcome when counselling patients to proceed to resective epilepsy surgery.

Purpose Hypothalamic hamartomas (HH) are rare benign lesions frequently associated with gelastic seizures early in life. Epilepsy can progress to multiple seizure types with cognitive impairment and behavioural disturbance, leading in some cases to epileptic encephalopathy. Methods We reviewed a retrospective series of 112 children treated in a single center, between 1998 and 2017. Results According to Delalande’s HH classification, type1 was found in 2 patients, type 2 in 67, type 3 in 31, and type 4 in 12 patients. Stereotactic endoscopic disconnection was performed in 92 % of the procedures. Median age at diagnosis was 40 months and 7.6 years at surgery. Median time between diagnosis and surgery was 31 months and median follow up 4.1 years. For all HH types, 77.6 % of the patients had a favourable outcome (Engel I + II outcome score) with 57.1 % seizure-free (Engel I). The best outcome was obtained in patients with type 2 HH, (68.7 % Engel I and 85.1 % Engel I + II). The overall complication rate was 8.3 %, which is in line with previous series. Patients with isolated gelastic seizures had a better outcome (Engel I + II in 90 %), as compared to those with other seizure types (p = 0.07). A short delay between hamartoma diagnosis and surgery was a statistically significant factor for a good outcome (p = 0.03). Conclusion Patients with HH and drug-resistant epilepsy should be early identified in order to propose surgical treatment without delay. Endoscopic disconnection is a safe and efficacious surgical option with good seizure outcome and immediate treatment results.

Recognition of insular epilepsy may sometimes be challenging due to the rapid speed at which insular seizures can spread throughout the cortex via extensive connections to surrounding cortices. The spectrum weighted adaptive directed transfer function, a multivariate causality-based effective connectivity measure, was applied to intracranial electroencephalography recordings to identify generators of seizure activity. A non-parametric test based on surrogate data testing was used to validate statistical significance of causal relations. Outflow and inflow of seizure activity were extracted from the computed transfer matrix. Recorded data of 21 seizures from seven patients were analyzed including five who were rendered seizure-free after operculo-insular resection. Effective connectivity analysis of 7 s following electrical onset confirmed an operculo-insular seizure origin in 5 patients with a good post-operative seizure outcome, and for whom the resected region was sampled by intracranial electroencephalography contacts. Different or additional seizure foci were identified in 2 patients with a bad post-operative seizure outcome. Findings highlight the feasibility of accurate operculo-insular seizure foci localization based on quantitative approaches.

Objective High frequency oscillations (HFO) between 80–500 Hz are markers of epileptic areas in intracranial and maybe also scalp EEG. We investigate simultaneous recordings of scalp and intracranial EEG and hypothesize that scalp HFOs provide important additional clinical information in the presurgical setting. Methods Spikes and HFOs were visually identified in all intracranial scalp EEG channels. Analysis of correlation of event location between intracranial and scalp EEG as well as relationship between events and the SOZ and zone of surgical removal was performed. Results 24 patients could be included, 23 showed spikes and 19 HFOs on scalp recordings. In 15/19 patients highest scalp HFO rate was located over the implantation side, with 13 patients having the highest scalp and intracranial HFO rate over the same region. 17 patients underwent surgery, 7 became seizure free. Patients with poor post-operative outcome showed significantly more regions with HFO than those with seizure free outcome. Conclusions Scalp HFOs are mostly located over the SOZ. Widespread scalp HFOs are indicative of a larger epileptic network and associated with poor postsurgical outcome. Significance Analysis of scalp HFO add clinically important information about the extent of epileptic areas during presurgical simultaneous scalp and intracranial EEG recordings.

Purpose The success of epilepsy surgery lies in identifying the ictal onset zone accurately. The significance of auras has little been explored on surgical outcome in drug-resistant epilepsy. This study focuses on the clinicopathological correlation of aura(s) and its role in predicting surgical outcome in drug-resistant temporal lobe epilepsy (TLE). We compared surgical outcome in TLE between patients with and without aura and identified the clinico-pathological, radiological and surgical differences between the two groups. Methods Consecutive patients who underwent presurgical evaluation from January 2009 to December 2014 for drug-resistant TLE who underwent anterior temporal lobectomy (ATL) were included. Patients were followed up at 3months, 12 months and then annually. Results Among 456 patients, 344(75%) had aura. Multivariate logistic regression showed that prototype EEG pattern at ictal onset (OR 2.12, 95% CI 1.18–3.06, p = 0.012) and right sided epileptogenic zone (OR 1.82 95% CI 1.18–3.78, p = 0.007) were significantly associated with presence of aura. There was no difference in surgical outcome between those with and without aura. But patients with auditory aura (OR 7.28, CI 2.80–18.95, p = 0.0002) and vertiginous aura (OR 3.01, CI 1.55–7.85, p = 0.028) had a poor surgical outcome. Bivariate analysis showed that normal MRI (p = 0.028) and normal/indeterminate pathology (p = 0.001) were significantly more common with auditory/vertiginous auras. Conclusions Mere presence of aura does not affect outcome after TLE surgery. However, auditory and vertiginous auras are predictors of poor surgical outcome. These patients require more extensive screening for an ictal onset zone beyond standard limits of ATL before surgery.

Purpose Focal cortical dysplasia (FCD) is the major cause of focal intractable epilepsy in childhood. Here we analyze the factors influencing the success of surgical treatment in a large cohort of children with histologically ascertained FCD. Method A retrospective study of the effects of FCD type, surgical intervention, and age at surgery in a pediatric cohort. Results A total of 113 patients (71 male; mean age at surgery 10.3 years; range 0–18) were analyzed; 45 had undergone lesionectomy, 42 lobectomy, 18 multi-lobectomy, and eight hemispherotomy. Complete seizure control (Engel Ia) was achieved in 56% after two years, 52% at five years, and 50% at last follow-up (18–204 months). Resections were more extensive in younger patients (40% of the surgeries affecting more than one lobe in patients aged nine years or younger vs. 22% in patients older than nine years). While resections were more limited in older children, their long-term outcome tended to be superior (42% seizure freedom in patients aged nine years or younger vs. 56% in patients older than nine years). The outcome in FCD I was not significantly inferior to that in FCD II. Conclusions Our data confirm the long-term efficacy of surgery in children with FCD and epilepsy. An earlier age at surgery within this cohort did not predict a better long-term outcome, but it involved less-tailored surgical approaches. The data suggest that in patients with an unclear extent of the dysplastic area, later resections may offer advantages in terms of the precision of surgical-resection planning.

Objective To evaluate the prognostic value of postoperative EEGs to estimate post anterior temporal lobectomy (ATL) seizure outcome. Methods We studied postoperative EEGs in 325 consecutive patients who had minimum five years of post-ATL followup. Interictal epileptiform discharges (IEDs) present only during sleep were classified as sleep IEDs. We defined favorable final-year outcome as no seizures during the final one year and favorable absolute-postoperative outcome as no seizures during the entire postoperative period. Results At mean follow-up of 7.3 ± 1.8 years, 281 (86.5%) patients had favorable final-year outcome while 161 (49.5%) had favorable absolute-postoperative outcome. IEDs on three months and one year EEG were associated with unfavorable outcomes while IEDs at 7th day had no association with outcomes. Sleep record increased the yield of IEDs by 30% at each time-point without compromising predictive value. EEG at one year predicted the risk of seizure recurrence on drug withdrawal. Conclusion While EEG at three months and at one-year after ATL predicted seizure outcome, EEG at 7th day was not helpful. Sleep record increases the sensitivity of postoperative EEG without compromising specificity. Significance Both awake and sleep EEG provide useful information in postoperative period following ATL.

Objectives: The resection of an epileptic focus provides a chance for seizure outcome regression, which markedly influences the level of patients' quality of life. One of its dimensions is the satisfaction with one's sexual life. Patients with epilepsy usually report low sexual satisfaction due to commonly diagnosed disturbances of sexual functions characterized by a multifactorial etiology. The aim of the study was to assess the level of satisfaction with their sexual life in patients after the surgical resection of an epileptic focus. Patients and methods: The study group included 63 patients who had undergone the surgical resection of an epileptic focus in a neurosurgical ward. The study was conducted with the present authors' own tool consisting of three parts. Result: The patients assessed their sexual life as moderately satisfactory (the average score was 4 out of a 7-grade scale). 38% of the respondents reported a complete withdrawal from sexual life, sporadic sexual activity or masturbatory behavior (instead of interactive behavior). This type of behavior correlates with the reduction in sexual satisfaction. Higher satisfaction is associated with initiating new behavior which is adequate to the patient's health status, more frequent sexual contacts or no changes between behavior before and after the surgery. Moreover, the removal of an epileptic focus reduced the fear of a possible seizure during intercourse. Conclusion: Based on the findings it may be assumed that the sexual satisfaction of patients with epilepsy after the resection of an epileptogenic focus is markedly affected by psychological factors, which should be considered in the therapeutic process. Keywords: Epilepsy, Sexual satisfaction, Epileptic focus resection, Quality of life

Epilepsy surgery is recommended in selected patients with Tuberous Sclerosis Complex (TSC). However, reports on predictive factors of seizure outcome are variable. Here we report on seizure and cognitive outcome of 35 TSC patients who received surgery for refractory epilepsy in 7 Italian centers over a period of 22 years (1997–2019). The rate of seizure-free individuals at last follow-up (mean 7.5 years, range 1–21 years) was 51%. Patients with longer follow-up (≥10 years) had a lower rate of Engel I outcome (11.1%) than those who received surgery in the last 10 years (65.4%, p = 0.003). Factors associated with Engel II, III, IV outcome in our cohort included: high number of cortical tubers (≥5); presence of subependymal nodules (SENs); seizure onset before age 1 year; and multifocal interictal epileptic discharges (IEDs) on electroencephalogram (EEG). A subset of patients evaluated with Vineland Adaptive Behaviour Scales (VABS) showed developmental gains, in line with their developmental trajectories, but no improvement in standard scores after surgery was noted. Our study demonstrates that the rates of successful seizure outcome of epilepsy surgery in TSC have improved in the last 10 years. More than half of the patients achieved seizure freedom, and a high proportion of affected individuals experienced a reduction in seizure burden and in antiseizure medications. A comprehensive assessment after surgery should be performed in TSC patients to evaluate the overall neurodevelopmental outcome, as measures that are based only on seizure control do not adequately identify the benefits of surgery on global functioning in these patients.

Introduction. We report our surgical series of intractable epilepsies investigated with stereoelectroencephalography (SEEG) at Westmead Hospital and The Children’s Hospital at Westmead; evaluating the methodology, complication rate and seizure outcome from an 8-year program. Methods. 82 SEEG were performed in 80 patients (males, n = 45) at Westmead Hospital and The Children’s Hospital at Westmead from 2012 to 2019. All SEEG were performed using frame-based stereotaxy with CRW (Integra, Plainsboro, NJ, USA) frame systems. Clinical demographics, methodology, outcomes and complications were collected and analysed. Results. Mean age of patients was 22 years old (range 4–49 years old). Two patients had two SEEG implantations because the initial implantation did not provide sufficient information to inform resection. Fifty-six patients had normal MRI. A total of 1132 electrodes were inserted in 82 SEEG procedures (mean number of electrodes per SEEG = 14, range 8–21; total number of electrode contact = 14611). Majority of patients had unilateral implantation (left = 24, right = 32, bilateral = 24). Complications occurred in four patients (subdural haemorrhage = 3, fractured electrode = 1). All patients were able to proceed with VEEG monitoring after electrode implantation. Seizures were recorded in 81 SEEG studies. One patient did not have any seizures during the evaluation. 72% of patients underwent resective surgery following SEEG. Two patients were offered resective surgery but had declined. 26% of patients were not localised. 13 patients were awaiting surgery or pending conference decision. 74% became seizure free after resective surgery. Conclusion. SEEG can be a relative safe and effective methodology for defining the epileptogenic zone.

The aim of this study was to evaluate the relationship between molecular markers and clinicopathological features in patients operated on for low-grade epilepsy-associated neuroepithelial tumors. Molecular-genetic signatures are becoming increasingly important in characterizing these lesions, which represent the second most common cause of focal epilepsy in patients undergoing epilepsy surgery. Data from 22 patients operated on for histopathologically confirmed low-grade epilepsy-associated neuroepithelial tumors were retrospectively collected. All specimens were examined for BRAF and IDH mutational status, 1p/19q codeletion and CD34 expression. The relationship between bio-molecular markers and several demographic, clinical and pathological features were analyzed. BRAF mutation was found in 11 (50.0%) patients and CD34 expression in 13 (59.1%). No patients presented IDH mutation or 1p/19q codeletion. Multiple seizure types were present in 5 (45.5%) patients with BRAF mutation and in none of those with BRAF wild type (p = 0.035). Moreover, BRAF mutation was predominant in right-sided lesions (p = 0.004) and CD34 expression was significantly associated with a longer duration of epilepsy (p = 0.027). Several other clinicopathological features, such as association with focal cortical dysplasia and postoperative seizure outcome, showed no significant correlation with molecular markers. Further studies are necessary both to confirm these data in larger cohort of patients and to investigate possible relationships between molecular markers and other clinicopathological features.

Purpose Using a novel technique based on phase locking value (PLV), we investigated the potential for features extracted from electrocorticographic (ECoG) recordings to serve as biomarkers to identify the seizure onset zone (SOZ). Methods We computed the PLV between the phase of the amplitude of high gamma activity (80–150Hz) and the phase of lower frequency rhythms (4–30Hz) from ECoG recordings obtained from 10 patients with epilepsy (21 seizures). We extracted five features from the PLV and used a machine learning approach based on logistic regression to build a model that classifies electrodes as SOZ or non-SOZ. Results More than 96% of electrodes identified as the SOZ by our algorithm were within the resected area in six seizure-free patients. In four non-seizure-free patients, more than 31% of the identified SOZ electrodes by our algorithm were outside the resected area. In addition, we observed that the seizure outcome in non-seizure-free patients correlated with the number of non-resected SOZ electrodes identified by our algorithm. Conclusion This machine learning approach, based on features extracted from the PLV, effectively identified electrodes within the SOZ. The approach has the potential to assist clinicians in surgical decision-making when pre-surgical intracranial recordings are utilized.

Purpose After surgery for intractable mesiotemporal lobe epilepsy (mTLE) seizures recur in 30–40%. One predictor for seizure recurrence is the distribution of seizure onset and interictal epileptiform discharges (IED). Our study focused on lateralization and extent of epileptiform activity regarding postoperative seizure persistence and the effect of reoperation. Methods This study comprises 426 consecutive patients operated for intractable mTLE. Impact of preoperative seizure onset and IED on the persistence of seizures and results of reoperation were analyzed. Results One year after surgery, 27% of patients with mTLE experienced persistent seizures (Engel II–IV). Preoperative bilateral seizure onset in EEG was predictive for postoperative seizure recurrence (Engel II–IV: 64%). Seizure foci and IED exceeding the temporal lobe in the ipsilateral hemisphere were not found to be associated with worse seizure outcome (Engel I: 72% and 75%) compared to patients with seizure foci confined to the ipsilateral temporal lobe (Engel I: 75% and 76%). Moreover, IED exceeding the affected temporal lobe in the ipsilateral hemisphere or even bilateral IED did not negatively affect seizure freedom if seizure onset was strictly limited to the affected temporal lobe (Engel I: 85% and 65%, respectively). 60% of patients reoperated in the ipsilateral temporal lobe for persistent seizures became seizure free. Conclusions Preoperative bilateral ictal foci are a negative predictor for seizure outcome. Contrarily, IED exceeding the affected temporal lobe in the ipsilateral hemisphere or even bilateral IED had favorable seizure outcome if seizure onset is strictly limited to the affected temporal lobe. Reoperation for seizure persistence constitutes a promising therapeutic option.

Introduction Recent ILAE classification defined focal cortical dysplasia (FCD) patients with accompanying epileptic lesions as a separate group. We investigated data of patients with sole FCD lesions regarding long-term seizure outcome and different characteristics of FCD type 1 and type 2 patients. Methods Eighty children and adult patients underwent surgery for FCD were included to the analysis of factors differentiating FCD type 1 and type 2 groups and their effect on long-term outcome. Results FCD type 2 patients had earlier epilepsy onset (8.1 vs. 6.1 years. p = 0.019) and underwent surgery younger than type 1 (18.2 vs. 23.7 years. p = 0.034). FCD type 2 patients were more prominently MR positive (77.8% vs. 53.8%. p = 0.029), which increased within FCD type 2 group as patients become younger (p = 0.028). FCD Type 1 lesions showed mostly multilobar extension and FCD type 2 mostly located in frontal lobe. Seizure freedom was achieved in 65.4% of FCD type 1 patients and 70.4% of FCD type 2 patients. Seven patients had permanent de novo neurological deficits. Mean follow-up time was 5.5 years (Range: 1–11 years). Conclusion Surgical intervention in carefully selected patients may facilitate favorable seizure outcome leading to better quality of life. FCD type 1 and type 2 groups present with evident differences, which may promote medical and surgical management of these pathologies.

In the surgical management of epilepsy, the resection of cortex exhibiting interictal fast ripples (250–500 Hz) on electrocorticography has been linked to postoperative seizure-freedom. Although fast ripples appear to accurately identify the epileptogenic zone—the minimum tissue that must be removed at surgery to achieve seizure-freedom—it has not been established that fast ripples are a superior biomarker in comparison with multimodal presurgical neuroimaging and other electrocorticography abnormalities. Hence, in the prediction of postoperative seizure-freedom, we compared the value of fast ripples with other intraoperative electocorticography abnormalities including focal slowing, paroxysmal fast activity, intermittent spike discharges, continuous epileptiform discharges, focal attenuation, and intraoperative seizures, as well as complete resection of the lesion defined by MRI and other neuroimaging. In a cohort of 60 children with lesional epilepsy and median postsurgical follow-up exceeding 4 years, who underwent resective epilepsy surgery with intraoperative electrocorticography, we evaluated the extent to which removal of each intraoperative electrocorticography abnormality impacts time to first postoperative seizure using the Kaplan-Meier method and Cox proportional hazards regression. Secondly, we contrasted the predictive value of resection of each competing electrocorticography abnormality using standard test metrics (sensitivity, specificity, positive predictive value, and negative predictive value). In contrast with all other intraoperative electrocorticography abnormalities, fast ripples demonstrated the most favorable combination of positive predictive value (100%) and negative predictive value (76%) in the prediction of postoperative seizures. Among all candidate electrocorticography features, time to first postoperative seizure was most strongly associated with incomplete resection of fast ripples (hazard ratio = 19.8, p

Fast ripples (FR, 250-500Hz) in the intraoperative corticogram have recently been proposed as specific predictors of surgical outcome in epilepsy patients. However, online FR detection is restricted by their low signal-to-noise ratio. Here we propose the integration of low-noise EEG with unsupervised FR detection.Pre- and post-resection ECoG (N=9 patients) was simultaneously recorded by a commercial device (CD) and by a custom-made low-noise amplifier (LNA). FR were analyzed by an automated detector previously validated on visual markings in a different dataset.Across all recordings, in the FR band the background noise was lower in LNA than in CD (p0.001). FR rates were higher in LNA than CD recordings (0.9±1.4 vs 0.4±0.9, p0.001). Comparison between FR rates in post-resection ECoG and surgery outcome resulted in positive predictive value PPV=100% in CD and LNA, and negative predictive value NPV=38% in CD and NPV=50% for LNA. Prediction accuracy was 44% for CD and 67% for LNA.Prediction of seizure outcome was improved by the optimal integration of low-noise EEG and unsupervised FR detection.Accurate, automated and fast FR rating is essential for consideration of FR in the intraoperative setting.

Purpose To review the long-term outcome of epilepsy in population-based studies. Method Analysis of population-based studies. Results About two of three patients with new-onset epilepsy will, in the long run, enter five-year terminal remission. Chances for remission are best for those with idiopathic or cryptogenic epilepsy. It is unclear whether the seizure outcome has improved over the last several decades. Social outcome, however, may have become better because of the improved level of knowledge on and public attitudes toward people with epilepsy, and possibly fewer prejudices at home, daycare, school, military and labor market. Conclusion While we still do not have a cure for epilepsy for all patients, relief of the medical and social consequences is available for many and hope is on the horizon for people with epilepsy.

To describe seizure outcome and complications in patients with cavernous malformations (CM) undergoing early versus late surgery.A database was created for all CM patients who presented with seizure referred to the neurosurgical clinic at an academic center. A telephone survey and chart review were conducted to evaluate for preoperative and postoperative seizure frequency. Postoperative seizure-free outcome of patients who had ≤2 preoperative seizures versus those that had2 preoperative seizures was compared.A total of 35 CM patients were included for analysis. Nineteen patients had ≤2 preoperative seizures and 16 patients had2 preoperative seizures, six of them drug resistant for over two years. Among the ≤2 seizure group, 15 had only a single seizure before surgical resection. 94.7% of patients with ≤2 preoperative seizures and 62.5% of patients with2 preoperative seizures were seizure free one year following surgical resection (p = 0.019). 78.9% of patients with ≤2 preoperative seizures and 25% of patients with2 preoperative seizures were able to wean off AEDs (p 0.001). Among those patients who had a single preoperative seizure, 100% of patients were seizure free at one year.Early surgical resection for CM patients who present after a CM-related seizure is an effective, well tolerated treatment and has good chance to offer seizure freedom without the need for long-term antiepileptic medications. Outcome for patients operated with only one or two preoperative seizures may lead to better results than patients who delay the procedure.

Background Hippocampal sclerosis (HS) is the most common cause of drug-resistant medial temporal lobe epilepsy (MTLE). Structural abnormalities such as HS, granule cell pathology (GCP), and focal cortical dysplasia (FCD) have been classified histopathologically, possibly allowing a more accurate assessment of prognostic seizure and neuropsychologic outcomes. We correlated seizure outcome with comprehensive temporal lobe pathologic findings, identified according to the most recent classification systems of HS, GCP, and FCD. Methods All the 83 patients who underwent anterior temporal lobectomy (ATL) for drug-resistant MTLE and with a proven diagnosis of HS between April 2001 and May 2014 were collected. Patients were divided in 2 main groups: 1) isolated HS with/without GCP (HS +/- GCP); and 2) HS associated with FCD with/without GCP (HS+FCD +/- GCP). Patients were followed up at least 1 year, and seizure outcome was reported in accordance with Engel classification. Results Group I: HS +/- GCP: Statistical analysis confirmed a better outcome in HS + GCP patients than in HS-no GCP (P < 0.05). Moreover, a better outcome for the patients affected by GCP type I was observed (P < 0.05). Group II: HS+FCD +/- GCP: Patients with HS variant type I presented a better seizure outcome than the patients with HS type II (Engel class IA HS type I vs. type II: 69% vs. 40%). Conclusions A pathology-based approach to epilepsy surgery might improve the interpretation of the results, could predict which cases will enjoy a better seizure outcome, and could help to the comprehension of the causes of failures.

Purpose To evaluate the long-term safety and seizure outcome in Japanese patients with Lennox–Gastaut syndrome (LGS) receiving adjunctive rufinamide therapy. Subjects and methods We conducted an open-label extension study following a 12-week multicenter, randomized, double-blind, placebo-controlled study of adjunctive rufinamide therapy in Japanese patients with LGS. Fifty-four patients participated in the extension study. Seizure frequency was evaluated until 52 weeks after the start of the extension study. Adverse events (AEs) were evaluated throughout both studies. Key findings Of the 54 patients, 41 (75.9%) completed the extension study. The median duration of exposure to rufinamide was 818.0 days in all 54 patients, and 38 patients (70.4%) received rufinamide for 2 years or more. The median percent change in the frequency of tonic–atonic seizures relative to the frequency at the start of the double-blind study was −39.3% (12 weeks), −40.6% (24 weeks), −46.8% (32 weeks), −47.6% (40 weeks), and −36.1% (52 weeks). Reduction of total seizure frequency was also maintained until 52 weeks. Frequent treatment-related AEs were somnolence (20.4%), decreased appetite (16.7%), transient seizure aggravation including status epilepticus (13.0%), vomiting (11.1%), and constipation (11.1%). Adverse events were mild or moderate, except for transient seizure aggravation in three patients. Adverse events resulting in discontinuation of rufinamide were decreased appetite, drug eruption, and worsening of underlying autism. When clinically notable weight loss was defined as a decrease ≥7% relative to baseline, 22 patients (40.7%) experienced weight loss at least once during long-term observation, although weight loss was reported as an AE in only three patients. Significance This study demonstrated a long-term benefit of rufinamide as adjunctive therapy for Japanese patients with LGS. Exacerbation of seizures and decreased appetite/weight loss should be monitored carefully.

Objectives “Long-term epilepsy associated tumors (LEATs)” by definition are tumors primarily causing drug-resistant seizures for two years or more. They include low-grade glial and glioneuronal tumors with normal life expectancy. We studied a large cohort of patients with LEATs who underwent surgery through our epilepsy program. Patients & methods From 1998–2011, 105 patients with LEATs underwent surgery in our center. We utilized their data archived in a prospective registry to evaluate their electro-clinical-imaging characteristics affecting the long-term seizure outcome. Results Of 105 patients (age 3–50 years), mean age at surgery was 20 years and mean pre-surgical duration of epilepsy was 10.9 years. 66 (62.8%) had secondary generalized seizures. 82 had temporal tumors, 23 had extra temporal (13 frontal, 3 parietal, 2 occipital and 5 multilobar lesions) and four had associated hippocampal sclerosis. The interictal discharges and ictal onset were concordant to the lesion in 82 (78%) and 98 (93%) patients respectively. Lesionectomy and/or adjoining corticectomy or temporal lobectomy was done. Ganglioglioma was the most dominant pathological substrate in 61 (58%). During a mean follow-up of 7.5 years (range 3–16 years), 78/105 (74.2%) were seizure-free and 45 (57.4%) were totally off drugs. Secondary generalized seizures (p-0.02), temporal location of tumor (p-0.008) and spikes in third month post-operative EEG (p-0.03) caused unfavorable seizure outcome. A pre-surgical duration of epilepsy of more than 6.6 years caused less than optimal surgical outcome Conclusions Early surgery should be considered a priority in LEATs. Presence of secondary generalized seizures is the single most important predictor of a poor seizure outcome.

The stereo-electroencephalography (SEEG) methodology and technique was developed almost 60 years ago in Europe. The efficacy and safety of SEEG has been proven. The main advantage is the possibility to study the epileptogenic neuronal network in its dynamic and 3-dimensional aspect, with optimal time and space correlation, with the clinical semiology of the patient's seizures. The main clinical challenge for the near future remains in the further refinement of specific selection criteria for the different methods of invasive monitoring, with the ultimate goal of comparing and validating the results (long-term seizure-free outcome) obtained from different methods of invasive monitoring.

Cavernous malformations (CM) are low-flow vascular lesions that can cause significant symptoms and neurological deficits. Different intraoperative surgical approaches have been developed. Aim of the present investigation is the comparison between the trans-sulcal approach (TS) and the trans-parenchymal neuronavigation-assisted approach (TPN) in a surgical series from two neurosurgical centers. The technique and clinical outcomes are discussed, with a specific focus on seizure outcome.Clinical and radiological data from two neurosurgical centers ("A. Gemelli" Hospital in Rome and A.O.U. Città della Salute e della Scienza in Turin) were retrospectively reviewed in order to evaluate the different outcome of TS and TPN approach for cavernous malformation treatment.A total of 177 patients underwent surgical intervention for supratentorial CM, 130 patients with TPN approach and 47 with TS approach. TS approach was associated with higher rate of seizure in early post-operative period both in epileptic patients (p 0,001) and in patients without history of seizures before surgery (p = 0,002). Moreover, length of incision (p 0,001), area of craniotomy (p 0,001) and corticectomy (p 0,001) were bigger in TS than in TPN approach. Brain contusion (p 0,001) and fluid collection (p 0,001) were more likely to be discovered after TS approach.TPN is a valuable approach for resection of CM. Minor complications are significantly lower in TPN approach when compared with TS approach. In addition, it is associated with lower rate of early post-operative seizure and shorter length of stay.

Purpose We investigated the rate of acceptance of functional seizures (FS) or psychogenic nonepileptic seizures (PNES) diagnosis in a cross-sectional study in a cohort from Iran. We hypothesized that the acceptance of FS diagnosis has association with clinical characteristics of the patients. Methods In this cross-sectional study, all patients with FS, who were diagnosed at Shiraz Comprehensive Epilepsy Center, Iran, from 2008 until 2018, were investigated. In a phone call interview in February 2020, we obtained the following information: whether they have accepted the diagnosis that was delivered to them; what is their seizure outcome (seizure-free during the past 12 months or not). Results 100 patients participated; at the time of the follow-up call, 74 (74%) patients expressed that they have accepted the diagnosis of FS. At the follow-up call, 48 patients (48%) were seizure-free and 52 patients (52%) were suffering from FS yet; 34 of seizure-free patients (71%) and 40 of those patients who still had seizures (77%) expressed that they have accepted the diagnosis of FS (p = .504; Fisher's exact test). Patients' characteristics and seizure semiology were not associated with the acceptance of the diagnosis of FS. Conclusion That the majority of patients with FS accept their diagnosis if it is delivered to them appropriately, and demographic and clinical characteristics of the patients do not have associations with this.

Background High-frequency oscillations (HFOs) are associated with epileptogenesis. Nevertheless, clinical implications of this marker are still limited. The objective of this study was to determine the diagnostic efficacy of high-frequency electrocorticography (HF-ECoG) in structural epilepsy surgery. Material and methods This is a retrospective study of 32 patients who underwent surgery for tumor-associated (subgroup 1, 11 pts) or pharmacoresistant (subgroup 2, 21 pts) epilepsy in Polenov Russian Neurosurgical Institute in 2017–2018. Comparison group included patients with tumors without epilepsy. HF-ECoG in all patients was recorded with subdural grid electrodes (AdTech, USA) before and after lesion resection via Mitsar-EEG-202 hardware (Russia). Epilepsy surgery outcome was assessed in 12 months postoperatively. The recordings were visually analyzed and HFO index (HFOi) was calculated. HFOi is the maximum of HFO-compromised seconds in all artifact-free minute-long epochs of HF-ECoG. Results Postoperatively in 25% of the cases in subgroup 1 and 50% of subroup 2 patients had seizures. Preresective HF-ECoG in comparison group showed morphologically similar HFOs to those in epilepsy patients. Preresective HFOi was higher in subgroup 2 vs 1 (mean - 27 ± 13.2% vs 13.6 ± 11.3%), probably due to the duration and severity of the disease. Presence of HFOs in postresective HF-ECoG in epilepsy patients was not associated with worse outcome. Significant reduction of HFOi correlated with good seizure outcome. Specificity equaled 85.7%, while sensitivity was 58.3%. Conclusions HFOs reflect the processes of epileptogenesis. HF-ECoG provides an opportunity to predict seizure outcome. However, this technique is still not considered self-sufficient for epilepsy surgery.

The aim of this study was to verify the presence of BRAF mutations in a series of six patients affected by drug-resistant focal epilepsy associated with neocortical posterior temporal gangliogliomas (GG) who were subjected to lesionectomy between June 2008 and November 2013. GG are an increasingly recognized cause of epilepsy and represent the most common tumor in young patients undergoing surgery for intractable focal epilepsy. BRAF mutations have been identified in up to 50% of GG. Interestingly, these six patients shared a specific anatomical posterior temporal site. In all patients, histological examination confirmed the diagnosis of GG, and two were also associated with a focal cortical dysplasia (FCD) type IIa. BRAF mutations were found in four out of six GG (66.6%). Furthermore, dysplastic tissue of Patient 2 showed a concomitant BRAF V600E mutation. All patients but one (83.3%) achieved Engel Class Ia seizure control. The patient carrying a concomitant BRAF mutation in GG and FCD fell into Engel Class II. Further analyses will be required in order to better understand the meaning of BRAF mutations in epilepsy-associated tumors and FCD and their possible role as a prognostic seizure outcome and tumor behavior marker.

Objective This study aimed to determine the contribution of EFHC1 variants to the phenotypic variability of juvenile myoclonic epilepsy (JME) and to evaluate their diagnostic value regarding previously identified clinical long-term seizure outcome predictors in a consecutive cohort of patients with JME. Methods Thirty-eight probands and three family members affected with JME were studied at a tertiary epilepsy center with a review of their medical records and a subsequent face-to-face interview. All coding EFHC1 exons and adjacent exon/intron boundaries were directly sequenced. Results The previously reported EFHC1 mutation F229L was found in two cases who presented with early generalized tonic–clonic seizure (GTCS) onset and appeared to be associated with milder subtypes of JME. Variant R294H was identified in two further probands who had a subtype of JME developing from childhood absence epilepsy. However, segregation of the phenotype with this variant could not be confirmed in one family. Conclusions Our findings corroborate the heterogeneity of JME as an electroclinical epilepsy syndrome and provide evidence that genetic factors may influence and help predict the long-term seizure outcome in patients with JME.

Purpose Surgery is regarded as a common treatment option for patients with mesial temporal lobe epilepsy (MTLE) as a result of hippocampal sclerosis (HS). However, approximately one-third of patients with intractable epilepsy did not become seizure-free after tailored resection strategies. It would be compelling to identify predictive factors of postoperative seizure outcomes. Our aim was to assess the correlation between HS classification and long-term postoperative seizure outcome in patients with MTLE due to HS. Methods To investigate HS classification, semi-quantitative analysis and immunohistochemical staining of neuronal nuclei (NeuN) were performed on 100 postoperative hippocampal specimens. All patients had a 1–7 year postoperative follow-up. The postoperative seizure outcome was evaluated using International League Against Epilepsy (ILAE) outcome classification. Results Three types of HS were recognized. The highest incidence of initial precipitating injury (IPI) was noted in the HS ILAE type 1 group (53.1%). The most favorable long-term seizure outcome was also noted in the HS ILAE type 1 group. The shortest epilepsy duration was recorded in the HS ILAE type 2 group (mean epilepsy duration=6.64±5.83 years). The completely seizure free rate of patients in all groups declined with an increase in time. Conclusions Our study for the first time demonstrated a significant correlation between HS ILAE types and long-term postoperative seizure outcome in patients with MTLE due to HS. Therefore, HS ILAE types have predictive value in long-term seizure outcome following epilepsy surgery.

Purpose: The primary aim of this study was to analyze the long-term outcomes of patients who were classified as Engel IV one year after resective epilepsy surgery. The secondary objectives were to evaluate the effectiveness of different treatment options and to examine the reasons that the patients did not undergo resective reoperation. Methods: Our study was designed as a retrospective open-label investigation of the long-term outcomes of 34 patients (12% of all surgically treated patients) who were classified as Engel IV one year after epilepsy surgery. Results: At the last follow-up visit (average of 7.6 +/- 4.2 years after surgery), 12 of the 34 examined patients (35.3%) were still classified as Engel IV; 22 of the 34 patients (64.7%) were improved (Engel I III). Of the 34 patients, 8 (23.5%) achieved an excellent outcome, classified as Engel I, 3 patients (8.8%) were classified as Engel II, and 11 patients (32.4%) as Engel III. The seizure outcome in the patients classified as Engel I was achieved by resective reoperation in 4; by a change in antiepileptic medication in 3 patients; and by vagus nerve stimulation (VHS) in 1 patient. The seizure outcome of Engel II was achieved by a change in antiepileptic medication in all 3 patients. Of the 34 patients, a total of 6 (17.6%) underwent resective reoperation only. The major reasons for this were the absence of a plausible hypothesis for invasive re-evaluation, the risk of postoperative deficit, and multifocal epilepsy in the rest of patients. Conclusion: Although the reoperation rate was relatively low in our series, we can achieve better or even excellent seizure outcomes using other procedures in patients for whom resective surgery initially failed.

Background This Scandinavian collaborative retrospective study of children treated with ketogenic diet (KD) highlights indications and effectiveness over two years follow-up. Methods Five centres specialised in KD collected data retrospectively on 315 patients started on KD from 1999 to 2009. Twenty-five patients who stopped the diet within four weeks because of compliance-problems and minor side-effects were excluded. Seizure-type(s), seizure-frequency, anti-epileptic drugs and other treatments, mental retardation, autism-spectrum disorder and motor-dysfunction were identified and treatment-response was evaluated. Results An intention-to-treat analysis was used. Responders (>50% seizure-frequency reduction) at 6, 12 and 24 months were 50%, 46% and 28% respectively, seizure-free were 16%, 13% and 10%. Still on the diet were 80%, 64% and 41% after 6, 12 and 24 months. No child had an increased seizure-frequency. The best seizure outcome was seen in the group with not-daily seizures at baseline ( n = 22), where 45%, 41% and 32% became seizure-free at 6, 12 and 24 months A significant improvement in seizure-frequency was seen in atonic seizures at three months and secondary generalised seizures at three and six months. Side-effects were noted in 29 subjects; most could be treated and only two stopped due to hyperlipidaemia and two due to kidney-stones. In 167 patients treated with potassium-citrate, one developed kidney-stones, compared with six of 123 without potassium-citrate treatment (relative risk = 8.1). Conclusions As the first study of implementing KD in children in the Scandinavian countries, our survey of 290 children showed that KD is effective and well tolerated, even in such severe patients with therapy-resistant epilepsy, more than daily seizures and intellectual disability in the majority of patients. Long-term efficacy of KD was comparable or even better than reported in newer AEDs. Addition of potassium citrate reduced risk of kidney-stones. Our data indicate that the response might be predicted by seizure-frequency before initiation of the diet but not by age, seizure-type or aetiology.

Purpose: Ictal fear is an uncommon condition in which fear manifests as the main feature of epileptic seizures. The literature has suggested that ictal fear is generally associated with poor seizure outcomes. We wanted to clarify the variability in seizure outcome of children with ictal fear. Subjects and methods: We identified five pediatric patients with ictal fear who were followed up on at Okayama University Hospital between January 2003 and December 2012. We retrospectively reviewed their clinical records and EEG findings. Results: The onset age of epilepsy ranged from 8 months to 9 years and 10 months. The common ictal symptoms were sudden fright, clinging to someone nearby, and subsequent impairment of consciousness, which were often accompanied by complex visual hallucinations and psychosis-like complaints. Ictal fear, in four patients, was perceived as a nonepileptic disorder by their parents. Ictal electroencephalograms (EEG) of ictal fear were obtained in all patients. Three showed frontal onset, while the other two showed centrotemporal or occipital onsets. Two patients were seizure free at last follow-up, while seizures persisted in the other three. A patient with seizure onset during infancy had a favorable outcome, which was considered to be compatible with benign partial epilepsy with affective symptoms. Conclusion: Ictal fear is not always associated with a symptomatic cause or a poor seizure outcome. It is quite important to make a correct diagnosis of ictal fear as early as possible to optimize treatment.

Purpose Most epilepsy surgery candidates are young adults. Outcome reports after epilepsy surgery in patients ≥50 years are few and varying. The aim of this study was to describe patient characteristics of older compared to younger adults and analyse seizure, complication and vocational outcomes in a large population-based series. Methods We analysed data from the Swedish National Epilepsy Surgery Register for 1990–2009 for patients ≥19 years at resective surgery who had completed two-year follow-up. Variables studied were seizure outcome, histo-pathological diagnoses, complications and vocational outcome. Data from patients ≥50 years and 19–49 years at surgery were compared. Results 558 Adults underwent resective epilepsy surgery 1990–2009 and had two-year follow-up. 12% of the adults (67 patients) were ≥50 years at surgery. Patients ≥50 had longer epilepsy duration, more often had mesial sclerosis and less often had neurodevelopmental tumours and cortical malformations. The proportion of seizure-free patients at two-year follow-up did not differ between those ≥50 and 19–49 years (61% versus 61% seizure-free last year, 48% versus 43% completely seizure-free since surgery), neither did the occurrence of major complications (3% in both groups). The vocational situation was mainly stable between baseline and two-year follow-up in both groups, although older patients were less often employed than younger. Conclusion 12% of adults in the Swedish series were ≥50 years at epilepsy surgery. Seizure outcome was as good for older as for younger adults, and there was no difference in the occurrence of major complications. This constitutes important information in the presurgical counselling process.

Purpose The view that juvenile myoclonic epilepsy (JME) is a uniform and life-long disorder is currently being challenged. The aim of this study was to assess the seizure and psychosocial outcome of JME at least 20 years after onset. Methods In 1992, 42 patients with JME were identified. In 2012, 37 agreed to a semi-structured interview. In the remaining five, only medical records were available. Results Of 40 patients with known seizure outcome, 21 were in remission for >5 years. Seven were off antiepileptic drugs (AEDs), four being seizure free for >10 years. Myoclonic seizures (MC) evolving to generalized tonic–clonic seizures (GTC) were associated with seizure persistence ( p =0.013), whereas >1 year between MC and GTC onset was associated with a trend to GTC remission ( p =0.069). Of 19 patients with uncontrolled seizures, eight experienced remission with second generation AEDs. Favorable psychosocial outcome by interview was found in a third, whereas another third had psychiatric comorbidity, seven with substance or alcohol abuse. Psychosocial and seizure outcome did not correlate. Conclusion This study corroborates the heterogeneity of JME in terms of seizure and psychosocial outcome, but without a clear association between the two. It confirms that seizure control may persist after AED withdrawal in some and supports MC evolving to GTC as a predictor of seizure persistence. Moreover, it suggests that newer broad spectrum AEDs may improve the prognosis of JME; their impact should be focus of prospective studies.

Objective The objective of this study was to retrospectively review the postoperative seizure outcome in patients with short duration of epilepsy associated with cavernous malformations and analyze the effect of surgical methods on seizure outcome in such population. Methods 36 patients with short duration of epilepsy (shorter than 12 months) associated with cavernous malformations in temporal or frontal lobe underwent microsurgical resection. The patients were retrospectively divided into two groups: Group A (21 patients) with complete removal of hemosiderin rim and Group B (15 patients) with partial removal of hemosiderin rim. Clinical follow-up was achieved with telephone correspondence or outpatient assessment. The seizure outcome was based on Engel’s classification. Results After a mean follow-up period of 18 months, 77.8% of the patients (28/36) were classified into Engel class I, including 19 patients (90.5%) in the complete removal of hemosiderin rim group (Group A) and 9 patients (60%) in the partial removal of hemosiderin rim group (Group B). Seizure outcome was significantly better in Group A. There was no mortality and all the postoperative neurological deficits were recovered at the time of follow-up. Conclusion The analysis of the seizure outcome demonstrate patients with short duration of epilepsy associated with cavernous malformations could benefit greatly from complete resection of hemosiderin rim and cavernous malformations.

To study the usefulness of the Wada test for predicting seizure outcome following anterior temporal lobectomy (ATL).From 1996 to 2002, all patients with left mesial temporal lobe epilepsy and hippocampal sclerosis (MTLE-HS) and selected patients with right MTLE-HS underwent the Wada test before ATL at our center. Patients were selected for ATL on the basis of unilateral HS on MRI and concordant electro-clinical data. Twelve-item recognition paradigm was used for Wada memory testing. Score of +1 was awarded for a correct response and -0.5 for an incorrect response. We defined Wada failure as a contralateral score of5, ipsilateral score of8, and difference score of0. No patient was denied surgery based on the Wada results. Means of the three scores were compared between seizure free and non-seizure free patients. Sensitivity, specificity and receiver operator characteristic curves of various scores for predicting seizure outcome were calculated.151 patients (129 left MTLE; mean age: 27.80±8.72 years) formed the study group. At mean postoperative follow-up of 6.4±2.0 years, 127 patients were seizure free. Mean contralateral score was lower in the seizure-free group (7.15±3.07 vs. 8.71±4.13; p0.001) while ipsilateral and difference scores were similar between the two seizure outcome groups. Areas under the curves for contralateral, ipsilateral and difference scores for predicting seizure-free outcome were 0.49, 0.58 and 0.59, respectively, suggesting its modest usefulness in individual patients. Results remained same when the analysis was restricted to left MTLE patients.Wada test has limited usefulness for predicting seizure outcome following ATL.

Purpose: To describe operative procedures, seizure control and complications of surgery for cortical dysplasia (CD) causing intractable epilepsy in infancy and early childhood. Methods: Fifty-six consecutive children (less than 6 years old) underwent resective epilepsy surgery for CD from December 2000 to August 2011. Age at surgery ranged from 2 to 69 months (mean 23 months) and the follow-up was from 1 to 11 years (mean 4 years 4 months). Results: Half of the children underwent surgery during infancy at an age less than 10 months, and the majority (80%) of these infants needed extensive surgical procedures, such as hemispherotomy and multi-lobar disconnection. Seizure free (ILAE class 1) outcome was obtained in 66% of the cases (class 1a; 55%): 85% with focal resection (n = 13), 50% with lobar resection (n = 18), 71% with multilobar disconnection (n = 7) and 67% with hemispherotomy (n = 18). Peri-ventricular and insular structures were resected in 23% of focal and 61% of lobar resections. Repeated surgery was performed in 9 children and 5 (56%) became seizure free. Histological subtypes included hemimegalencephaly (16 patients), polymicrogyria (5 patients), and FCD type I (6 patients), type IIA (19 patients), type IIB (10 patients). Polymicrogyria had the worst seizure outcome compared to other pathologies. Surgical complications included 1 post-operative hydrocephalus, 1 chronic subdural hematoma, 2 intracranial cysts, and 1 case of meningitis. No mortality or severe morbidities occurred. Conclusions: Early surgical intervention in children with CD and intractable seizures in infancy and early childhood can yield favorable seizure outcome without mortality or severe morbidities although younger children often need extensive surgical procedures.

Purpose The association between pre-surgical psychiatric disorders (PDs) and worse seizure outcome in patients with refractory epilepsy submitted to surgery has been increasingly recognized in the literature. The present study aimed to verify the impact of pre- and post-surgical PD on seizure outcome in a series of patients with refractory temporal lobe epilepsy and mesial temporal sclerosis (TLE–MTS). Method Data from 115 TLE–MTS patients (65 females; 56.5%) who underwent cortico-amygdalohippocampectomy (CAH) were analyzed. Pre- and post-surgical psychiatric evaluations were performed using DSM-IV and ILAE criteria. The outcome subcategory Engel IA was considered as corresponding to a favorable prognosis. A multivariate logistic regression model was applied to identify possible risk factors associated with a worse seizure outcome. Results Pre-surgical PDs, particularly major depressive disorder (MDD), anxiety and psychotic disorders, were common, being found in 47 patients (40.8%). Fifty-six patients (48.7%) were classified as having achieved an Engel IA one year after CAH. According to the logistic regression model, the presence of pre-surgical MDD (OR=5.23; p =0.003) appeared as the most important risk factor associated with a non-favorable seizure outcome. Conclusion Although epilepsy surgery may be the best treatment option for patients with refractory TLE–MTS, our findings emphasize the importance of performing a detailed psychiatric examination as part of the pre-surgical evaluation protocol.

Objective High-gamma oscillations (HGOs) (60–99 Hz) have been suggested to correlate with seizure onset zones and seizure outcomes. We investigated the correlation between the extent of removal of ictal HGO generating areas and postoperative seizure outcome in neocortical epilepsy (NE). Methods Twenty three patients with medically intractable NE underwent chronic intracranial electroencephalography (iEEG) using subdural electrodes. Ictal HGOs and superimposed undersampled ripples within ±3 s of video-iEEG ictal onset were extracted by wavelet clustering and thresholding. Cluster epileptogenicity indices (CEIs) were calculated. The temporal analysis window was locked to the timing of the maximum CEI wavecluster. Root mean square amplitudes, cross-correlation synchronies and the local focus indices within the temporal window were calculated. Results Percentages of resected maximum CEI waveclusters and HGO zones with high standardised amplitudes (>3), high cross-correlation synchronies (>0.9) and high local focus indices (>2) were significantly higher in the seizure-free group compared to the not seizure-free group (p = 0.036, p = 0.018, and p = 0.026, respectively). Conclusions The automatic quantitative ictal HGO analysis may be effective in delineating the epileptogenic zone. Significance HGO analysis may be helpful for improving post-resection seizure outcome in NE in the future.

Objective To clarify the clinical significance of ictal high frequency oscillations (HFO) in the medial temporal lobe. Methods This study included 19 patients who underwent intracranial electrode implantation in bilateral temporal lobes and had at least one seizure recorded at 1 kHz sampling rate. The characteristics of ictal HFO in the medial temporal lobe, and the relations between the presence of HFO, pathology, and postoperative seizure outcome were analyzed. Results Ictal HFO were detected from medial temporal structures in 11 patients with medial temporal lobe epilepsy (MTLE). Among eight patients without HFO, only three were diagnosed with MTLE. Ictal HFO were detected from unilateral medial temporal structures ipsilateral to the side of hippocampal sclerosis (HS). In one patient with bitemporal independent seizure onset, ictal HFO were detected only on the side of HS. HS was detected in all 11 patients with HFO, but in only one of four patients without HFO. Seizure outcome did not differ between patients with and without HFO. Conclusions Ictal HFO in the medial temporal lobe may be a specific marker for MTLE with HS. Significance Recording of ictal HFO in the medial temporal lobe may be useful for presurgical evaluation of MTLE.

Summary Objective The objective of this retrospective study is to analyze whether preoperative functional imaging studies using FDG-PET and MEG enable prediction of postoperative seizure outcomes. Methods Thirty-six patients with intractable temporal lobe epilepsy were studied. Asymmetry index of tCMRgluc (PET-AI) and the equivalent current dipole intensity of first response of SEF (SEF-AI) were determined preoperatively using 18 F-fluorodeoxyglucose-positron emission tomography (FDG-PET) and magnetoencephalography (MEG), respectively. Seizure outcomes were evaluated according to the classification proposed by the International League Against Epilepsy (ILAE) at least 24 months after resection of epileptic focuses. Twelve healthy volunteers were included in this study to determine the normal value. Results Quantitative analysis revealed mean PET-AI in the patients was 5.4±5.2% (significantly different from normal controls); mean SEF-AI was 25.2±20.6% (not significantly different). PET-AI was positive (indicative of epileptic focus) in 29 of 36 patients (80.6%), while SEF-AI was positive in 17 of 36 patients (47.2%). Although no significant correlation between PET-AI and SEF-AI was noted ( r =0.43), concordant asymmetry in both PET-AI and SEF-AI was significantly associated with better seizure outcome than discordant or paradoxical asymmetry of both factors ( p Conclusions The results suggest that quantitative analysis of tCMRgluc with SEF may be helpful in characterizing the preoperative epileptogenic condition and predicting postoperative seizure outcome in patients with temporal lobe epilepsy, although a constellation of developmental brain abnormalities and environmental factors that together produce epilepsy need to be further explored.

One hundred fifty-one neurologists at U.S. epilepsy centers responded to a survey on stopping medications in patients following successful resective epilepsy surgery. Sixty-two percent said patients should be > or = 2 years seizure-free before stopping medication. Although respondents tended to agree about the importance of many of the queried factors (e.g., focal pathology in favor of and persistent auras against stopping antiepileptic drugs), it is unclear how well these factors determine seizure outcome in this setting.

Summary Purpose To investigate the factors, including those associated with ictal scalp EEG results, related to surgical outcome in patients with pathologically proven mesial temporal sclerosis. Methods We studied 51 consecutive patients who underwent anterior temporal lobectomy and had at least 4 years of follow-up. Surgical outcome was classified as being seizure-free or not seizure-free during the first two and the subsequent two postoperative years. Clinical variables and scalp EEG parameters were subjected to statistical analysis. Results Of the 51 patients, 36 (70.6%) were seizure-free during postoperative years 3 and 4. Logistic regression analysis revealed that seizure remission for the first 2 years ( p =0.002) and contralateral propagated ictal discharges ( p =0.015) were independently related to seizure outcome at 4 years. Patients who were seizure-free at 2 years had an 86.5% chance of remaining seizure-free at 4 years. Of the patients without bitemporal asynchrony or switch of lateralization, 88.9% were seizure free at 4 years, compared with 54.5% of patients with asynchrony or switch of lateralization ( p =0.007). These two factors, however, were not predictive of seizure outcome at 2 years. Conclusions Contralateral propagated ictal discharges, including bitemporal asynchrony and switch of lateralization, unfavorably influence long-term seizure outcome. Long-term seizure control is best when the patient has no such propagation patterns of ictal discharges and is seizure-free during the first 2 years after temporal lobectomy.

The objective of this study was to correlate health-related quality of life (HRQOL) after surgery for mesial temporal lobe epilepsy, as revealed by a postoperative screening tool, to different modalities of seizure outcome classification (Engel, International League Against Epilepsy (ILAE)).One hundred twenty-eight of one hundred forty consecutive patients returned a HRQOL questionnaire at a mean of 36 months after selective amygdalohippocampectomy. Patients answered in two ways: with an absolute estimation (values 1-4) and with a self-rated relative change (-1, 0, +1) after surgery.Eighty patients were seizure- and aura-free (63.3% ILAE 1), 16 continued to have auras (12.5% ILAE 2), and 13 experienced 1-3 seizure days per year after surgery (10.2% ILAE 3). Ninety-two patients were classified seizure-free (71.9% Engel I), and 17 had two or fewer seizures per year (13.3% Engel II). Of 110 patients in ILAE 1-3, 100 (91%) stated good or even very good postoperative HRQOL, and 99 (90.0%) reported improvements in HRQOL. Only 9 of the remaining 18 (50%) reported good or very good HRQOL after surgery (P=0.01). Corresponding results were obtained with Engel classes I and II, suggesting a trend toward ILAE 1-3 and Engel I and II as overall satisfactory outcomes. A more detailed HRQOL assessment yielded lowest scores in the cognitive domain, and a significant correlation of self-rated changes in cognitive functioning with seizure control (P=0.01). Changes in physical capabilities and mood were significantly better with satisfactory seizure outcome (P=0.006 and P0.001, respectively), whereas the social aspects were not significantly dependent on seizure outcome (P=0.06).Correlation of HRQOL and seizure control suggested that ILAE 1-3 and Engel I and II most likely represent overall satisfactory outcome. Subdomain analyses revealed cognitive abilities as the most critical feature associated with seizure control, whereas social aspects remained mainly stable.

Summary Rationale Mesial temporal sclerosis (MTS) is an important pathology in temporal lobe epilepsy (TLE) and often associated with good surgical outcome, however prognostic factors for surgical outcome are conflicting. The authors examine seizure outcome after surgery for TLE due to MTS, with focus on the presence of polyglucosan bodies (PGBs), and its relation to the epileptogenic process. Methods Records of 44 consecutive patients with intractable TLE who underwent anterior temporal lobectomy (ATL) at JFK medical center between 1994–2001 were reviewed. Details of clinical, electrophysiological evaluation, and outcome were collected. All slides were reviewed for the presence of MTS. In twenty-one patients with MTS, detailed histology of surgical specimens was reviewed and relative concentration of PGBs was assessed. The postoperative follow-up duration ranges between 28–74 months. Surgical outcome was evaluated according to Engel’s classification. Results Data of fourteen females (mean age 32.8 years) and 7 males (mean age 34.2) were analyzed. PBGs were identified in 10 patients (8 females and 2 males). All 10 patients had good surgical outcome, with 6 patients (60%) being seizure free (class 1) and 4 patients as class 2. While 11 patients (6 males and 5 females) with absent PGB, 72.8% had good surgical outcome. Of these, 7 (63.8%) had class 1, 1 patient had class 2, and 3 patients had class 3&4. Assessing several risk factors, the only significant difference between the two groups was epilepsy duration, which was significantly longer in patients with PGBs (P = 0.011). Conclusion The histological presence of PGB is associated with long duration of epilepsy and could be the consequence of epilepsy. Despite prolonged duration of epilepsy, the surgical outcome in PGBs +ve is similar to PGBs −ve patients.

SummaryWe investigated the correlation of interictal epileptiform discharges (IED) in routine EEG 6 and 24 months after epilepsy surgery with regard to long-term seizure outcome. In 148 patients (74% temporal lobe epilepsy (TLE), 26% extratemporal epilepsy) EEG results (IED present or absent) were correlated with the postoperative outcome using the Engel classification 6 and 24 months after resection (PO6m and PO2y, respectively). Self-evaluation was conducted 3 and 5 years after resection (PO3y and PO5y, respectively). Ninety-one patients (62%) were seizure-free 5 years after resection; 88% of them showed no IED in PO6m. Twenty-eight patients (19%) displayed IED in routine EEG 6 months after resection; 61% of them had recurrent seizures at PO5y, whereas of 120 patients without IED only 33% had recurrent seizures at PO5y; p=0.01.Absence of IED in PO6m and PO2y correlated with good outcome: 71% without IED remained seizure-free, whereas only 25% with IED at PO6m and PO2y remained seizure-free; p=0.001.Seizure-free patients (Engel 1) and patients with less favourable outcome (Engel 3–4) at PO6m and PO2y rarely changed categories of outcome during the following years (p

Surgical alleviation of chronic epilepsy can give rise to a process of adjustment as the chronically ill patient learns to become well. This process can manifest clinically as an array of symptoms which we have previously described as the ‘burden of normality’. The aim of this study was to explore the longitudinal course of post-operative adjustment by mapping the incidence of symptoms of the burden of normality over a period of 2 years, and examining symptom occurrence relative to seizure outcome. A series of 90 anterior temporal lobectomy (ATL) patients was drawn from our Seizure Surgery Follow-up and Rehabilitation Program. All patients were prospectively assessed using the Austin CEP Interview, which covers symptoms of the burden of normality. In total, 66% of patients reported symptoms at some time within the first 2 years of surgery. Symptoms often emerged by the 3 month review, but were still seen frequently in the second year. At the 24 month review, patients who had been seizure free or experienced auras only within the previous 18 months were significantly more likely to report symptoms compared to patients who had experienced complex partial and/or generalized tonic–clonic seizures (P= 0.03). Surgical alleviation of seizures in chronic epilepsy brings with it the burden of normality. Recognition of this syndrome is essential in maximizing patient outcome.