Long-term Seizure Outcome Research Articles

Malformations of cortical development as models of altered brain excitability

The developmental organisation of the human cerebral cortex is among the most complex processes known in biology. The process includes the migration of neuronal precursors from the cortical endplate to the future outer boundary of the brain, a consistent organisation in layers from the inside to the outside, the differentiation of principal neurons and a wide spectrum of inhibitory neuronal types focusing information processing and controlling excitability, and the precision wiring of neurons within cortical columns and in extended projections. This process results in an efficient, stable, and functional small-world brain network. Unsurprisingly, the complex sequences and interactions contributing to this cortical development are liable to minor and major disturbances. Progress in brain imaging and in the histological analysis of brain specimens, particularly from humans undergoing neurosurgical resections of brain areas considered pathological, has considerably increased knowledge from the spectrum of malformations of cortical development. Such malformations can be extensive (eg, the formation of a double cortex or absent cortical layering, or altered gyrification, such as in pachygyria, or can be circumscribed (as with focal cortical dysplasia), or can be space occupying (as with a developmental tumour). Abnormal neuronal migration, differentiation, and wiring will often affect the intricate balance of excitability and inhibition in the affected brain region, resulting in epilepsy. Improved high resolution brain imaging, including computer-assisted postprocessing of 3D data sets, 1 Gill RS Lee HM Caldairou B et al. Multicenter validation of a deep learning detection algorithm for focal cortical dysplasia. Neurol. 2021; (published online Sep 14)https://doi.org/10.1212/WNL.0000000000012698 Crossref Scopus (10) Google Scholar , 2 Demerath T Rubensdörfer L Schwarzwald R et al. Morphometric MRI analysis: improved detection of focal cortical dysplasia using the MP2RAGE sequence. AJNR Am J Neuroradiol. 2020; 41: 1009-1014 Crossref PubMed Scopus (12) Google Scholar has provided evidence that discrete focal brain malformations are the most common cause of focal epilepsy in people, and particularly of focal epilepsy that responds insufficiently to anti-seizure medication and thus requires surgical treatment. 3 Fauser S Essang C Altenmüller DM et al. Long-term seizure outcome in 211 patients with focal cortical dysplasia. Epilepsia. 2015; 56: 66-76 Crossref PubMed Scopus (113) Google Scholar , 4 Blümcke I Spreafico R Haaker G et al. EEBB Consortium. Histopathological findings in brain tissue obtained during epilepsy surgery. N Engl J Med. 2017; 377: 1648-1656 Crossref PubMed Scopus (370) Google Scholar Neocortical development and epilepsy: insights from focal cortical dysplasia and brain tumoursDuring the past decade, there have been considerable advances in understanding of the genetic and morphogenic processes underlying cortical malformations and developmental brain tumours. Focal malformations are caused by somatic (postzygotic) variants in genes related to cell growth (ie, in the mTOR pathway in focal cortical dysplasia type 2), which are acquired in neuronal progenitors during neurodevelopment. In comparison, developmental brain tumours result from somatic variants in genes related to cell proliferation (eg, in the MAP-kinase pathway in ganglioglioma), which affect proliferating glioneuronal precursors. Full-Text PDF

Long-term seizure outcomes in patients with hypothalamic hamartoma treated by stereotactic radiofrequency thermocoagulation.

To investigate long-term seizure outcomes in patients with hypothalamic hamartoma (HH) following stereotactic radiofrequency thermocoagulation (SRT). A total of 131 patients with HH who underwent SRT and were followed for at least three years after the last SRT were enrolled. Seizure outcomes were evaluated for gelastic seizures (GS) and other types of seizures (nGS) separately using the International League Against Epilepsy classification. Classes 1 and 2 were considered seizure-free. Kaplan-Meier survival analyses were used to estimate the proportion remaining seizure-free after the first and last SRTs. Risk factors relating to outcomes were analyzed by log-rank tests and a multivariate Cox proportional hazards model. Reoperation was performed in 34 patients (26.2%). Median total follow-up was 61 (range, 36-202) months. Seizure freedom was obtained in 116 patients (88.6%) for GS and 85 of 108 patients (78.7%) for nGS at the last follow-up. Mean GS-free survival times improved from after the first (64.1 [95%CI 57.3-70.9] months) to after the last SRT (80.2 [95%CI 75.7-84.8] months). About 90% of GS recurrences after the first SRT were found within 6months, though a few patients recurred more than 2years after the first SRT. On the other hand, mean nGS-free survival times after the first and last SRTs were not different between after the first SRT (84.4 [95%CI 73.0-90.7] months) and after the last SRT (83.1 [95%CI 74.1-92.0] months). There was no factor related to GS outcomes, but the significant factor for nGS-free survival after the last SRT was multiple previous treatments (p=0.01, hazard ratio=15.65, 95%CI 1.79-137.16). The last SRT was almost equivalent to achieving complete disconnection of HHs from the hypothalamus according to our strategy. Considering the epileptogenic network, GS outcomes depend on complete disconnection, whereas nGS outcomes are not affected by surgical factors but independency of secondary epileptogenesis.

P14.34 Long-term seizure outcomes and tumor recurrence after glioneural tumor surgery: A single-center retrospective cohort

Abstract BACKGROUND Gangliogliomas (GG) and dysembryoplastic neuroepithelial tumors (DNET) are glioneural tumors associated with treatment refractory seizures, especially in younger patients. Because there is a relative paucity of data on which factors predispose patients for recurrences, we analyzed our own cohort treated over the last 25 years. MATERIAL AND METHODS We performed a retrospective analysis of all patients undergoing resection of a glioneural tumor with a minimum follow up of one year. Surgery type, histological findings, and seizure outcome were extracted from patient records. Recurrence was defined as new tumor lesions in previously unremarkable parenchyma or tumor growth of a residual lesion. We performed a Mann-Whitney-U test to determine statistical significance of differences in continuous variables and Fisher’s exact test in categorical. RESULTS In total, 109 patients were operated between March 1994 to March and followed for a median of 62.4 months (range 12–281 months). The average age of patients at the time of surgery was 21.2 years with 60 patients belonging to the pediatric population. Complete lesionectomies were the goal in 72 cases, extended resections in 10, and partial resection due to proximity of eloquent areas was performed in 27 cases. 77 tumors were classified histologically as a GG and 32 as a DNET. The temporal lobe was the most common site of origin with 65 tumors (59.6%) being found there. On postoperative MRI, complete resection was achieved in 76 cases. Local tumor recurrences were seen in 14 patients (12 GG and 2 DNET), 9 of which occurred in patients with apparently complete resection. Overall, only one malignant transformation of a GG was observed. Age at surgery was significantly lower for patients with later recurrence (11.9 yrs vs. 22.6 yrs for patients without recurrence, p=0.0047). A second surgery was performed in 11 patients with previously incomplete resections (33%) and 7 patients with complete resection (9.2%), p=0.0038. 95 patients (87.2%) had preoperative seizures for a median of 26 months before surgery. One year after surgery, a documented ILAE outcome was available for 90 of these patients and 63 (70%) were seizure free one year after surgery. While 45 patients with epilepsy (47.4%) had at least one seizure relapse after surgery - most often associated with AED withdrawal or tumor recurrence - medical therapy and repeat resection allowed 76 patients (80%) to be seizure free for over one year at their last follow up. Age at surgery was not a significant predictor of seizure freedom. CONCLUSION Glioneural tumors are highly epileptogenic but neurosurgical resection allows seizure freedom in the large majority of these patients. Tumor recurrences were more likely in younger patients and incomplete resections predisposed patients to need another surgery. Resection extent on MRI does not appear to be a reliable marker for future recurrence risk.

Imaging in the presurgical evaluation of epilepsy

Während zwei Drittel der PatientInnen mit Epilepsie durch Medikamente anfallsfrei werden, ist die Erkrankung bei 30 % pharmakoresistent. Bei pharmakoresistenter fokaler Epilepsie bietet die Epilepsiechirurgie eine etwa 65 %ige Chance auf Anfallsfreiheit. Vorab muss der Anfallsfokus exakt eingegrenzt werden, wofür bildgebende Methoden unverzichtbar sind. In den letzten Jahren hat sich in der Prächirurgie der Anteil von PatientInnen mit unauffälliger konventioneller Magnetresonanztomographie (MRT) erhöht. Allerdings konnte die Sensitivität der MRT durch spezielle Aufnahmesequenzen und Techniken der Postprozessierung gesteigert werden. Die Quellenlokalisation des Signals von Elektro- und Magnetenzephalographie (EEG und MEG) verortet den Ursprung iktaler und interiktaler epileptischer Aktivität im Gehirn. Nuklearmedizinische Untersuchungen wie die interiktale Positronen-Emissions-Tomographie (PET) und die iktale Einzelphotonen-Emissionscomputertomographie (SPECT) detektieren chronische oder akute anfallsbezogene Veränderungen des Hirnmetabolismus und können auch bei nichtlokalisierendem MRT auf den epileptogenen Fokus hinweisen. Alle Befunde zusammengenommen werden zur Planung eventueller invasiver EEG-Ableitungen und letztlich der chirurgischen Operation eingesetzt. Konkordante Befunde sind mit besseren chirurgischen Ergebnissen assoziiert und zeigen auch im Langzeitverlauf signifikant höhere Anfallsfreiheitsraten.

Long-term seizure outcomes in patients with anti-Leucine-rich glioma-inactivated 1 encephalitis

BackgroundThis study aimed to investigate the semiology of seizure disorders, including electroencephalographic characteristics, and seizure outcomes in participants with anti-leucine-rich glioma-inactivated 1 (LGI-1) encephalitis. MethodsSeventy participants who presented with seizures during the acute phase of anti-LGI-1 encephalitis at Peking Union Medical College Hospital from May 2013 to July 2020 were reviewed. All participants underwent follow-up for longer than 2 years. ResultsAt the time of presentation, 48 (68.6%) participants had generalized seizures and 57 (81.4%) had focal seizures. The most common focal motor seizures were faciobrachial dystonic seizures (FDS). The main manifestations of focal nonmotor seizures were dyscognitive features, goosebumps, and disorders of sensation. All participants received immunomodulatory therapy. Thirty-five (50%) participants were seizure free after 1 year of follow-up, and 48 (68.6%) participants were seizure free over a follow-up of 2 years. Participants with seizures continued longer than 1 year were older than participants whose seizure duration was shorter than 1 year (P = 0.021). However, after an extended follow-up period, the difference between the incidences of seizures based on age was not significant. The frequency of focal motor seizures was higher in participants who became seizure free within 1 year, compared to participants who had seizures for longer than 1 year (75% vs 54.3%, respectively; P = 0.015). Participants with seizures continued over 2 years tended to have focal nonmotor seizures, and tended to show an elevated incidence of abnormal EEG results. Participants receiving early corticosteroid and longer duration immunosuppressant treatments, tended to have a lower risk of persistent seizures and better seizure outcomes, with no statistical significance. ConclusionsMost participants obtained remission from seizures after immunomodulatory therapy. The seizure manifestation of anti-LGI1 encephalitis is diverse and variable. The type of focal seizures may affect the outcome of participants with seizures. Older age could lead to longer duration of the seizure disorder, but did not affect the rate of seizures over the long term. Early and prolonged administration of immunomodulatory therapy may be useful for shortening the time to becoming seizure free.

Neuroimaging in pediatric temporal lobe epilepsy: Does neuroimaging accurately predict pathology and surgical outcome?

Temporal lobe epilepsy (TLE) in children is considered different from that in adults. As such, characterizing the structural lesions present in pediatric patients with TLE and their association with long-term seizure control is important. Here, we aimed to assess the concordance between preoperative imaging and postoperative histopathological diagnoses and their associations with seizure outcomes in pediatric patients with TLE undergoing temporal lobe surgery.We retrospectively reviewed the charts of pediatric patients with TLE who underwent surgical treatment between 1988 and 2020 as a part of the Comprehensive Epilepsy Program at the University of Alberta. Demographic, age at seizure onset, age at surgery, preoperative electroencephalography (EEG), long-term video EEG, imaging (magnetic resonance imaging [MRI] and computed tomography), neuropathology, and long-term seizure outcome data were acquired and analyzed.One hundred and seventeen patients underwent surgery for refractory TLE; the preoperative MRI diagnosis was concordant with the histopathological diagnosis in 76 % of cases. Tumors were identified with high accuracy (91 %). Mesial temporal sclerosis (MTS) was strongly associated with an excellent outcome after surgery (94 %). Patients with normal imaging results or non-specific pathologies were more likely to experience poor seizure outcomes after surgery (50 %).The radiological identification of lesions was associated with good long-term seizure outcomes, whereas normal MRI results were associated with significantly poorer long-term seizure outcomes. An accurate preoperative MRI is essential to epilepsy surgery since it impacts all stages of management; these results will thereafter help inform practitioners’ efforts to predict seizure outcome.

Predictors and Long-term Outcome of Resective Epilepsy Surgery in Patients with Tuberous Sclerosis Complex: A Single-centre Retrospective Cohort Study

Objective: To identify prognostic factors and long-term seizure outcomes for patients with tuberous sclerosis complex (TSC) who underwent resective treatment for epilepsy. Methods: We enrolled 81 patients with TSC who had undergone resective epilepsy surgery at Sanbo Brain Hospital, Capital Medical University, between April 2004 and June 2019. We estimated cumulative probability of remaining seizure-free and plotted survival curves. Variables were compared using Mann–Whitney U, Pearson's correlation, continuity correction, and Fisher's exact chi-square tests. Prognostic predictors were analysed using log-rank (Mantel–Cox) tests and Cox regression models. Results: At the last follow-up, 48 (59.3%) patients were classified as International League Against Epilepsy Class 1 (including 14 patients who had seizures <3 times postoperatively on the same or different day and were seizure-free at all other times). The estimated cumulative probability of remaining seizure-free postoperatively was 69.0% (95% confidence interval [CI] 58.8–79.2%), 61.9% (95% CI 51.1–72.7%), and 55.0% (95% CI 42.8–67.2%) at 2, 5, and 10 years, respectively. The mean time of remaining seizure-free was 7.24 ± 0.634 years (95% CI 6.00–8.49); en bloc resection was an essential positive predictor of postoperative seizure freedom, as was age at seizure onset, regional interictal video-electroencephalography pattern, and temporal lobe surgery. The longer the seizure-free time, the less likely a relapse. Patients who postoperatively experienced seizures remained likely to recover. Conclusions: We demonstrated the efficacy of surgical treatment for patients with TSC and intractable epilepsy. Detailed perioperative tests are a reliable predictor of postoperative seizure freedom.

Long-term seizure outcome and antiseizure medication use in autoimmune encephalitis

PurposeTo determine long-term seizure outcome, use of antiseizure medication (ASM) and seizure recurrence risk after its withdrawal in patients with autoimmune encephalitis (AE) due to neuronal surface and GAD antibodies. MethodsIn patients from a specialized AE outpatient clinic, we assessed seizure manifestation, ASM and immunotherapy at onset of AE as well as seizure occurrence, development of autoimmune-associated epilepsy (AAE) and use of ASM in the long-term. Data were collected from patients via telephone interviews and medical records. ResultsOut of 94 AE patients, 75 were analyzed; 47 patients had NMDAR, 17 LGI1, 7 GAD, 3 CASPR2 and 1 mGluR5 antibodies. Fifty-three of the 75 patients (71 %) experienced seizures, all of which for the first time occurred at AE onset. After a median follow-up of 6 years (range, 1–15), 47 of the 53 AE patients had 1-year terminal seizure remission, median duration of terminal seizure freedom was 5 years. Rate of 1-year terminal seizure remission was significantly higher in patients with neuronal surface antibodies (NMDAR 97 %, LGI1 93 %, CASPR2 100 %) compared to patients with GAD antibodies (20 %, p < 0.001). In seizure-free patients, ASM was withdrawn after 13 months (median) without any relapse seizures. ConclusionsSeizures are common in most forms of AE manifesting at disease onset in all cases. However, the development of AAE is rare and typically occurs in patients with GAD antibodies. Thus, in most AE cases with neuronal surface antibodies, ASM can be withdrawn after the acute phase of AE with low risk of seizure relapse.

Long-term seizure outcome after resective temporal lobe surgery in a pediatric cohort: a single-center retrospective study

Long-term seizure outcome after resective temporal lobe surgery in a pediatric cohort: a single-center retrospective study

Multilobar Epilepsy Surgery in Childhood and Adolescence: Predictors of Long-Term Seizure Freedom.

Although multilobar resections correspond to one-fifth of pediatric epilepsy surgery, there are little data on long-term seizure control. To investigate the long-term seizure outcomes of children and adolescents undergoing multilobar epilepsy surgery and identify their predictors. In this retrospective study, we considered 69 consecutive patients that underwent multilobar epilepsy surgery at the age of 10.0± 5.0 yr (mean±SD). The magnetic resonance imaging revealed a lesion in all but 2 cases. Resections were temporo-parieto(-occipital) in 30%, temporo-occipital in 41%, parieto-occipital in 16%, and fronto-(temporo)-parietal in 13% cases. Etiologies were determined as focal cortical dysplasia in 67%, perinatal or postnatal ischemic lesions in 23%, and benign tumors in 10% of cases. At last follow-up of median 9 yr (range 2.8-14.8), 48% patients were seizure free; 33% were off antiepileptic drugs. 10% of patients, all with dysplastic etiology, required reoperations: 4 of 7 achieved seizure freedom. Seizure recurrence occurred mostly (80%) within the first 6 mo. Among presurgical variables, only an epileptogenic zone far from eloquent cortex independently correlated with significantly higher rates of seizure arrest in multivariate analysis. Among postsurgical variables, the absence of residual lesion and of acute postsurgical seizures was independently associated with significantly higher rates of seizure freedom. Our study demonstrates that multilobar epilepsy surgery is effective regarding long-term seizure freedom and antiepileptic drug withdrawal in selected pediatric candidates. Epileptogenic zones-and lesions-localized distant from eloquent cortex and, thus, fully resectable predispose for seizure control. Acute postsurgical seizures are critical markers of seizure recurrence that should lead to prompt reevaluation.

The utility of arterial spin labeling in the presurgical evaluation of poorly defined focal epilepsy in children.

The authors sought to assess the utility of arterial spin labeling (ASL) perfusion 3T-MRI for the presurgical evaluation of poorly defined focal epilepsy in pediatric patients. Pseudocontinuous ASL perfusion 3T-MRI was performed in 25 consecutive children with poorly defined focal epilepsy. ASL perfusion abnormalities were detected qualitatively by visual inspection and quantitatively by calculating asymmetry index (AI) maps and significant z-score cluster maps based on successfully operated cases. ASL results were prospectively compared to scalp EEG, structural 3T-MRI, FDG-PET, ictal/interictal SPECT, magnetoencephalography (MEG), and intracranial recording results, as well as the final surgically proven epileptogenic zone (EZ) in operated patients who had at least 1 year of good (Engel class I/II) seizure outcome and positive histopathology results. Qualitative ASL perfusion abnormalities were found in 17/25 cases (68%), specifically in 17/20 MRI-positive cases (85.0%) and in none of the 5 MRI-negative cases. ASL was concordant with localizing scalp EEG findings in 66.7%, structural 3T-MRI in 90%, FDG-PET in 75%, ictal/interictal SPECT in 62.5%, and MEG in 75% of cases, and with intracranial recording results in 40% of cases. Eleven patients underwent surgery; in all 11 cases the EZ was surgically proven by positive histopathology results and the patient having at least 1 year of good seizure outcome. ASL results were concordant with this final surgically proven EZ in 10/11 cases (sensitivity 91%, specificity 50%). All 10 ASL-positive patients who underwent surgery had positive surgical pathology results and good long-term postsurgical seizure outcome at a mean follow-up of 39 months. Retrospective quantitative analysis based on significant z-score clusters found 1 true-positive result that was missed by qualitative analysis and 3 additional false-positive results (sensitivity 100%, specificity 23%). ASL supports the hypothesis regarding the EZ in poorly defined focal epilepsy cases in children. Due to its convenience and noninvasive nature, the authors recommend that ASL be added routinely to the presurgical MRI evaluation of epilepsy. Future optimized quantitative methods may improve the diagnostic yield of this technique.

Consequences of mesial temporal sparing temporal lobe surgery in medically refractory epilepsy

ObjectiveWe compared long-term seizure outcome, neuropsychological outcome, and occupational outcome of anterior temporal lobectomy (ATL) with and without sparing of mesial structures to determine whether mesial sparing temporal lobectomy prevents memory decline and thus disability, with acceptable seizure outcome. MethodsWe studied patients (n = 21) and controls (n = 21) with no evidence of mesial temporal sclerosis (MTS) on MRI who had surgery to treat drug-resistant epilepsy. Demographic and pre- and postsurgical clinical characteristics were compared. Patients had neuropsychological assessment before and after surgery. Neuropsychological analyses were limited to patients with left-sided surgery and available data (n = 14 in each group) as they were at risk of verbal memory impairment. The California Verbal Learning Test II (CVLT-II) (sum of trials 1–5, delayed free recall) and the Logical Memory subtest of the Wechsler Memory Scale III or IV (WMS-III or WMS-IV) (learning and delayed recall of prose passages) were used to assess verbal episodic learning and memory. Seizure and occupational outcomes were assessed. ResultsThe chance of attaining seizure freedom was similar in the two groups, so sparing mesial temporal structures did not lessen the chance of stopping seizures. Sparing mesial temporal structures mitigated the extent of postoperative verbal memory impairment, though some of these individuals suffered decline as a consequence of surgery. Occupational outcome was similar in both groups. SignificanceMesial temporal sparing resections provide a similar seizure outcome as ATL, while producing a better memory outcome. Anterior temporal lobectomy including mesial structure resection did not increase the risk of postoperative disability.

Focal Cortical Surface Cooling is a Novel and Safe Method for Intraoperative Functional Brain Mapping

Electric cortical stimulation (ECS) has been the gold standard for intraoperative functional mapping in neurosurgery, yet it carries the risk of induced seizures. We assess the safety of focal cortical cooling (CC) as a potential alternative to ECS. We reviewed 40 patients (13 with tumor and 27 with mesial temporal lobe epilepsy) who underwent intraoperative CC at the University of Iowa Hospital and Clinics (CC group), of whom 38 underwent ECS preceding CC. Intraoperative and postoperative seizure incidence, postoperative neurologic deficits, and new postoperative radiographic findings were collected to assess CC safety. Fifty-five patients who underwent ECS mapping without CC (ECS-alone group) were reviewed as a control cohort. Another 25 patients who underwent anterior temporal lobectomy (ATL) without CC or ECS (no ECS/no CC-ATL group) were also reviewed to evaluate long-term effects of CC. Seventy-nine brain sites in the CC group were cooled, comprising inferior frontal gyrus (44%), precentral gyrus (39%), postcentral gyrus (6%), subcentral gyrus (4%), and superior temporal gyrus (6%). The incidence of intraoperative seizure(s) was 0% (CC group) and 3.6% (ECS-alone group). The incidence of seizure(s) within the first postoperative week did not significantly differ among CC (7.9%), ECS-alone (9.0%), and no ECS/no CC-ATL groups (12%). There was no significant difference in the incidence of postoperative radiographic change between CC (7.5%) and ECS-alone groups (5.5%). Long-term seizure outcome (Engel I+II) for mesial temporal epilepsy did not differ among CC (80%), ECS-alone (83.3%), and no ECS/no CC-ATL groups (83.3%). CC when used as an intraoperative mapping technique is safe and may complement ECS.

Long-term seizure, comorbidity and socioeconomic outcomes of patients with convulsive epilepsy in rural West China

PurposeThis study aimed to investigate the long-term outcomes of patients with convulsive epilepsy in rural West China and to explore potential related factors. MethodsPatients who were provided Phenobarbital as a treatment and followed-up monthly were enrolled from the Convulsive Epilepsy Control and Management Program in West China. Their clinical and demographic information were obtained from the program database and a questionnaire. Seizure outcomes, comorbidities, annual income, marital status, employment and quality of life (QOL) were evaluated as long-term outcomes. Logistic regression was used to analyze the related factors. ResultsOf 473 eligible patients with a median follow-up time of nearly 7 years, 312 (66 %) had one-year terminal remission. A total of 320 (67.7 %) patients had a low annual income (<5000 Yuan), and 198 (41.9 %) patients reported a comorbidity. Among 460 patients of marriageable age, 137 (29.8 %) were unmarried. 60.4 % (333) patients reported improved QOL. Time of follow-up, seizure frequency during early treatment, compliance, annual cost for epilepsy treatment and annual income were related to the seizure outcome. Baseline seizure frequency was associated with comorbidities. Sex, annual cost for epilepsy treatment and seizure outcomes were associated with annual income. Age, sex and age at onset were correlated with current marital status. Compliance and taking traditional Chinese medicine were associated with QOL. ConclusionThe prognosis of epilepsy goes beyond being seizure-free. Comorbidities, income and marriage outcomes in resource-poor areas are less promising. Systematic management considering prognosis-related factors for epilepsy by a collaboration of health providers and society is needed.

International consensus classification of hippocampal sclerosis and etiologic diversity in children with temporal lobectomy

IntroductionThe distribution of hippocampal sclerosis (HS) subtypes, according to the classification of the International League Against Epilepsy (ILAE), has been reported mainly in adult patients. We aimed to review the pathological findings in children who had anterior temporal lobectomy accompanied with amygdalohippocampectomy, in view of the current classification, and evaluate postsurgical outcome with respect to HS subtypes in childhood. MethodsSeventy children who underwent temporal resections for treatment of medically refractory epilepsy, with a minimum follow-up of 2 years, were included; the surgical hippocampus specimens were re-evaluated under the HS ILAE classification. ResultsNeuropathological evaluations revealed HS type 1 in 38 patients (54.3%), HS type 2 in 2 (2.8%), HS type 3 in 21 patients (30%), and no HS in 9 patients (12.9%). Of 70 patients, 23 (32.9%) had dual pathology, and the most common pattern was HS type 3 with low-grade epilepsy-associated brain tumors (LEAT). The distribution of HS types with respect to age revealed that HS type 3 and no HS subgroups had significantly more patients younger than 12 years, compared with those of HS type 1 (90.5%, 77.8% vs 47.4%, respectively). History of febrile seizures was higher in HS type 1. Prolonged/recurrent febrile seizures were most common in patients 12 years and older, whereas LEAT was the most common etiology in patients under 12 years of age (p < 0.001). Patients with HS type 1 had longer duration of epilepsy and an older age at the time of surgery compared with patients with HS type 3 and no HS (p: 0.031, p: 0.007). At final visit, 74.3% of the patients were seizure-free. Seizure outcome showed no significant difference between pathological subtypes. ConclusionsOur study presents the distribution of HS ILAE subtypes in an exclusively pediatric series along with long-term seizure outcome. The study reveals that the leading pathological HS subgroup in children is HS type 1, similar with adult series. Hippocampal sclerosis type 2 is significantly less in children compared with adults; however, HS type 3 emerges as the second most predominant group because of dual pathology, particularly LEAT. Further studies are required regarding clinicopathological features of isolated HS in pediatric cohort. Seizure-free outcome was favorable and similar in all HS types in children. The proportion of HS types may be better defined in pediatric patients with temporal resections, as the current HS ILAE classification becomes more widely used, and may help reveal the surgical and cognitive outcome with respect to HS types.

Multiple hippocampal transections for refractory pediatric mesial temporal lobe epilepsy: seizure and neuropsychological outcomes.

Temporal lobe epilepsy (TLE) is the most common focal epilepsy across adult and pediatric age groups. It is also the most amenable to surgery, with excellent long-term seizure outcome. Most TLE cases have an epileptogenic zone in the mesial temporal structures, namely the hippocampus. Resecting the dominant hippocampus has been shown to be associated with significant verbal memory deficits, especially in patients with intact verbal memory scores presurgically. Multiple hippocampal transection (MHT) is a relatively new surgical technique designed to interrupt the longitudinal hippocampal circuitry involved in seizure propagation yet preserve the circular fibers involved in memory function. This technique has been used to treat mesial TLE in both dominant- and nondominant-hemisphere cases, almost exclusively in adults. It has been applied to normal and sclerotic hippocampi. In this study, information on 3 pediatric patients who underwent MHT for mesial TLE at Children's Wisconsin between 2017 and 2018 is included. Clinical, electroencephalographic, and neuropsychological features and outcomes are described in detail. MRI revealed a tumor in the amygdala with a normal hippocampus in 1 patient and hippocampal sclerosis in 2 patients. All patients underwent stereoelectroencephalography confirming the involvement of the hippocampus in seizure onset. MHTs were completed under intraoperative monitoring, with amygdala and temporal tip resection in all patients due to early spread to these regions. All patients had excellent seizure outcomes at 1 year, and 2 of the 3 patients remain seizure free at last follow-up (range 20-36 months), all with stable or improved neuropsychological profiles, including verbal memory. MHT is a relatively new surgical procedure designed to preserve essential memory circuitry while disrupting seizure propagation pathways in the hippocampus. A growing body of literature shows good seizure and neuropsychological results, but mainly in adults. This is the first series of MHTs used exclusively in children at one medical center, showcasing excellent seizure control and preservation of neuropsychological functioning. One of the patients is also the first described to have MHT in the setting of an amygdalar tumor abutting the hippocampus, further expanding the pathological setting in which MHT can be used effectively.

Predictors of Outcome in Juvenile Myoclonic Epilepsy.

BackgroundJuvenile myoclonic epilepsy (JME) is the most common idiopathic generalized epilepsy syndrome, accounting for 10% of all epilepsy. However, there is limited information regarding the predictors of seizure outcome. The aim of this study was to determine the predictors of seizure outcome in JME patients.MethodsA population-based retrospective study of JME patients who were treated at the Department of Neurology of affiliated Zhongshan Hospital, Xiamen University from 2008 to 2013.ResultsSixty-three patients (30 women and 33 men) were enrolled in this study. The median age at seizure onset was 14 years old, and the average duration of epilepsy was 5 years. The onset of JME at age <16 years was found in 63.5% of patients. The epileptiform runs ≥3 s were observed in 35.8% patients. Febrile seizure was noted in 28.9% of patients. Among 63 patients, 40 patients (63.5%) had remission. Multivariate analysis identified the following factors as significant predictors of seizure outcome: the onset of JME at age <16 years, epileptiform runs ≥3 s runs, and febrile seizure.ConclusionThe onset of JME at age <16 years, febrile seizures and epileptiform runs ≥3 s might be associated with poor long-term seizure outcome in patients with JME.

Epilepsy surgery beyond 50 years: Long-term seizure and cognitive outcomes

IntroductionSurgery is a well-demonstrated effective treatment for patients with refractory epilepsy. However, there are scarce data about the efficacy in older patients. Endpoint was to evaluate the outcome of epilepsy surgery in pharmacorresistant patients operated in middle-late adulthood. MethodsWe conducted a retrospective observational study including patients who underwent a epilepsy surgery at age ≥ 50. Presurgical clinical data, type of surgery, and postsurgical seizure outcome and neurological complications, including neuropsychological assessment were analyzed. Minimum post-surgical follow-up was 1 year. ResultsWe identified 38 patients (22 males, 17 females) out of 350 patients who underwent a resective surgery with curative intention in our Epilepsy Unit (12%). Median age at surgery was 56 years (50–69), with median epilepsy duration of 42 years (4–67). Neuroimaging showed focal epileptogenic lesions in 37 patients, mainly mesial temporal sclerosis (21). Presurgical neuropsychological evaluation was available in 38 patients: 35 had deficits, mostly in verbal or visual memory.Twenty-eight patients underwent standard temporal lobectomy with amygdalohippocampectomy, 7 lesionectomy and 4 lobectomy. Median follow-up was 4.46 years (1–9.75). A good outcome was achieved by 86.8% (28 Engel I; 5 Engel II); 5 patients were studied with SEEG, without any complications. None had postsurgical permanent neurological complications. From 22 patients with available post-surgical neuropsychological assessment, 16 scored lower than in pre-surgical one, mainly in memory domain. ConclusionSurgical treatment of long-term refractory epilepsy in patients ≥50 years can be effective and safe. Post-surgical memory decline is a frequent side effect, but with a low impact in daily life.

Clinical features and electroclinical evolution in 22 cases with epileptic spasms without hypsarrhythmia.

This study aimed to investigate the general presentation of epileptic spasms without hypsarrhythmia (ESwoH) and retrospectively determine whether there are differences in treatment effects related to ACTH therapy, long-term seizure outcome, and evolution of EEG features according to pre-treatment EEG patterns. According to the pattern of background activity, we divided our cohort into two groups: Group 1: normal background activity or with localized intermittent slow waves; Group 2: intermittent slow waves appearing generalized or in two or more lobes. Subjects included 22 children (Group 1: n=10; Group 2: n=12) diagnosed with ESwoH who received treatment from 2007 to 2017. The median age at onset of epileptic spasms was 5.5 months and the follow-up period lasted for 40.5 months. ACTH therapy was performed for seven patients from Group 1 and eight patients from Group 2. Only one patient from Group 2 responded to ACTH. Patients receiving effective treatments at early stages had excellent seizure outcome. Refractory cases included six patients in Group 1 and eight patients in Group 2; subsequent follow-up EEGs indicated hypsarrhythmia in one patient in Group 1 (17%) and six patients (75%) in Group 2, including one patient whose EEG pattern indicated progression to Lennox-Gastaut syndrome. Overall, ACTH is ineffective for patients with epileptic spasms without hypsarrhythmia. The EEG may indicate possible future development of hypsarrhythmia if epileptic spasms are resistant to treatment, especially in patients with diffuse slow waves on pre-treatment EEG. The efficacy of treatment introduced at early stages from onset may predict long-term seizure outcome.

Resective epilepsy surgery in tuberous sclerosis complex: a nationwide multicentre retrospective study from China

At least 50% of patients with tuberous sclerosis complex present with intractable epilepsy; for these patients, resective surgery is a treatment option. Here, we report a nationwide multicentre retrospective study and analyse the long-term seizure and neuropsychological outcomes of epilepsy surgery in patients with tuberous sclerosis complex. There were 364 patients who underwent epilepsy surgery in the study. Patients' clinical data, postoperative seizure outcomes at 1-, 4-, and 10-year follow-ups, preoperative and postoperative intelligence quotients, and quality of life at 1-year follow-up were collected. The patients' ages at surgery were 10.35 ± 7.70 years (range: 0.5-47). The percentage of postoperative seizure freedom was 71% (258/364) at 1-year, 60% (118/196) at 4-year, and 51% (36/71) at 10-year follow-up. Influence factors of postoperative seizure freedom were the total removal of epileptogenic tubers and the presence of outstanding tuber on MRI at 1- and 4-year follow-ups. Furthermore, monthly seizure (versus daily seizure) was also a positive influence factor for postoperative seizure freedom at 1-year follow-up. The presence of an outstanding tuber on MRI was the only factor influencing seizure freedom at 10-year follow-up. Postoperative quality of life and intelligence quotient improvements were found in 43% (112/262) and 28% (67/242) of patients, respectively. Influence factors of postoperative quality of life and intelligence quotient improvement were postoperative seizure freedom and preoperative low intelligence quotient. The percentage of seizure freedom in the tuberectomy group was significantly lower compared to the tuberectomy plus and lobectomy groups at 1- and 4-year follow-ups. In conclusion, this study, the largest nationwide multi-centre study on resective epilepsy surgery, resulted in improved seizure outcomes and quality of life and intelligence quotient improvements in patients with tuberous sclerosis complex. Seizure freedom was often achieved in patients with an outstanding tuber on MRI, total removal of epileptogenic tubers, and tuberectomy plus. Quality of life and intelligence quotient improvements were frequently observed in patients with postoperative seizure freedom and preoperative low intelligence quotient.