Rasmussen encephalitis: long-term outcome after surgery

Structural signatures of language reorganization after left hemispherotomy in patients with Rasmussen's encephalitis

Rasmussen's encephalitis (RE) is a rare neurological disorder affecting a single cerebral hemisphere, often requiring hemispherotomy as a curative treatment. While significant brain plasticity occurs due to the pathology and surgical intervention, the mechanisms underlying cognitive functioning in the remaining hemisphere remain poorly understood. This multiple-case study longitudinally investigates neurocognitive reorganization in childhood after left hemispherotomy for RE and identifies structural patterns in the right hemisphere associated with language recovery. Indeed, the mechanisms that allow the right hemisphere to support language, after left hemispherotomy remain unclear. Cognitive trajectories were analyzed in three RE patients, and their cortical thickness (CT) changes were compared with data from a publicly available cohort of 393 healthy subjects. Language neuropsychological scores and T1-weighted MRI data were assessed in the healthy right hemisphere before hemispherotomy, one year, and five years post-surgery. Specifically, principal component analysis, structural covariance, and graph theory approaches were employed to investigate language network organization in patients and controls. Results reveal diverse language recovery trajectories among the three patients. Regarding CT, three potential signatures associated with favorable language outcomes were identified: (1) normal or below-normal CT values in cortical regions; (2) a more associative and integrative organization of the language network; and (3) increased global efficiency. These preliminary longitudinal findings provide novel insights into the mechanisms of neurocognitive reorganization following left hemispherotomy in childhood. By emphasizing structural patterns linked to favorable postoperative language recovery, this study highlights their value for guiding future research and clinical interventions.

Rasmussen Encephalitis: Clinical Features, Pathophysiology, and Management Strategies-A Comprehensive Literature Review

Rasmussen encephalitis (RE) is a rare and progressive form of chronic encephalitis that typically affects one hemisphere of the brain and primarily occurs in pediatric individuals. The current study aims to narratively review the literature about RE, including historical information, pathophysiology, and management of this condition. RE often occurs in individuals with normal development, and it is estimated that only a few new cases are identified each year in epilepsy centers. Approximately 10% of cases also occur in adolescents and adults. The hallmark feature of RE is drug-resistant focal seizures that can manifest as epilepsia partialis continua. Also, patients with RE usually develop motor and cognitive impairment throughout the years. Neuroimaging studies show progressive damage to the affected hemisphere, while histopathological examination reveals T-cell-dominated encephalitis with activated microglial cells and reactive astrogliosis. The current therapy guidelines suggest cerebral hemispherotomy is the most recommended treatment for seizures in RE, although significant neurological dysfunction can occur. Another option is pharmacological management with antiseizure medications and immunomodulatory agents. No significant progress has been made in understanding the pathophysiology of this condition in the last decades, especially regarding genetics. Notably, RE diagnosis still depends on the criteria established by Bien et al., and the accuracy can be limited and include genetically different individuals, leading to unexpected responses to management.

Insights on cognitive reorganization after hemispherectomy in Rasmussen's encephalitis. A narrative review

Rasmussen's encephalitis is a rare neurological pathology affecting one cerebral hemisphere, therefore, posing unique challenges. Patients may undergo hemispherectomy, a surgical procedure after which cognitive development occurs in the isolated contralateral hemisphere. This rare situation provides an excellent opportunity to evaluate brain plasticity and cognitive recovery at a hemispheric level. This literature review synthesizes the existing body of research on cognitive recovery following hemispherectomy in Rasmussen patients, considering cognitive domains and modulatory factors that influence cognitive outcomes. While language function has traditionally been the focus of postoperative assessments, there is a growing acknowledgment of the need to broaden the scope of language investigation in interaction with other cognitive domains and to consider cognitive scaffolding in development and recovery. By synthesizing findings reported in the literature, we delineate how language functions may find support from the right hemisphere after left hemispherectomy, but also how, beyond language, global cognitive functioning is affected. We highlight the critical influence of several factors on postoperative cognitive outcomes, including the timing of hemispherectomy and the baseline preoperative cognitive status, pointing to early surgical intervention as predictive of better cognitive outcomes. However, further specific studies are needed to confirm this correlation. This review aims to emphasize a better understanding of mechanisms underlying hemispheric specialization and plasticity in humans, which are particularly important for both clinical and research advancements. This narrative review underscores the need for an integrative approach based on cognitive scaffolding to provide a comprehensive understanding of mechanisms underlying the reorganization in Rasmussen patients after hemispherectomy.

Beyond the Pump: A Narrative Study Exploring Heart Memory

The field of organ transplantation, particularly heart transplantation, has brought to light interesting phenomena challenging traditional understandings of memory, identity, and consciousness. Studies indicate that heart transplant recipients may exhibit preferences, emotions, and memories resembling those of the donors, suggesting a form of memory storage within the transplanted organ. Mechanisms proposed for this memory transfer include cellular memory, epigenetic modifications, and energetic interactions. Moreover, the heart's intricate neural network, often referred to as the "heart brain," communicates bidirectionally with the brain and other organs, supporting the concept of heart-brain connection and its role in memory and personality. Additionally, observations from hemispherectomy procedures highlight the brain's remarkable plasticity and functional preservation beyond expectations, further underscoring the complex interplay between the brain, body, and identity. However, ethical and philosophical questions regarding the implications of these findings, including the definition of death and the nature of personal identity, remain unresolved. Further interdisciplinary research is needed to unravel the intricacies of memory transfer, neuroplasticity, and organ integration, offering insights into both organ transplantation and broader aspects of neuroscience and human identity. Understanding these complexities holds promise for enhancing patient care in organ transplantation and deepens our understanding of fundamental aspects of human experience and existence.

The Important Role of Hemispherotomy for Rasmussen Encephalitis: Clinical and Functional Outcomes

BACKGROUND

Rasmussen encephalitis (RE) is characterized by pharmacoresistant epilepsy and progressive neurological deficits concurrent with unilateral hemispheric atrophy. Evidence of an inflammatory autoimmune process has been extensively described in the literature; however, the precise etiology of RE is still unknown. Despite data supporting a beneficial effect of early immunosuppressive and immunomodulatory interventions, surgical disconnection of the affected hemisphere is considered the treatment of choice for these patients. The aim of this study was to report a series of children and adolescents who underwent hemispheric surgery (HS) for the treatment of RE, analyzing their clinical, electrographic, and neuroimaging features pre-operatively, as well as their postoperative status, including seizure and functional outcomes.

METHODS

All patients with RE who underwent HS in the Epilepsy Surgery Center (CIREP) of the University Hospital of Ribeirão Preto Medical School, between 1995 and 2020 were retrospectively reviewed. Preoperative and postoperative analyses included gender; age at epilepsy onset; seizure semiology; seizure frequency; interictal and ictal electroencephalographic (EEG) findings; age at surgery; duration of epilepsy; surgical complications; duration of follow-up; histopathological findings; and postoperative seizure, cognitive, and functional outcomes.

RESULTS

Forty-four patients were evaluated. Mean age at seizure onset and epilepsy duration was 6 years and 2.5 years, respectively. Mean age at surgery was 9 years, with an average follow-up ranging from 3 months to 23 years. All patients presented with severe epilepsy and distinct neurological abnormalities on MRI. Before HS, different degrees of abnormal intellectual performance as well as hemiparesis were seen in 86% and 90%, respectively. Histopathology examination confirmed this diagnosis in 95% patients. At the last follow-up, 68% of patients were seizure free, and 70% were classified as Engel Class I or II. Postoperatively, the cognitive status remained unchanged in 64% of patients. Likewise, the gross motor function remained unchanged in 54% of patients and 74% had functional hand ability after HS.

CONCLUSIONS

Considering the progressive damage course of RE, hemispheric surgery should be offered to pediatric patients. It has manageable risks and results in good seizure outcome, and the preoperative functional status of these children is often preserved (even when the left hemisphere is involved), thus improving their quality of life.

Long-term seizure outcome and mobility after surgical treatment for Rasmussen encephalitis in children: A single-center experience

OBJECTIVE

Rasmussen Encephalitis (RE) is a rare inflammatory neurodegenerative disease associated with refractory seizures, hemiparesis, and cognitive deterioration, due to lateralized cortical atrophy. Hemispheric surgery (hemispherotomy) is the mainstay of treatment, but its unavoidable motor deficits and lack of long-term data regarding seizure outcomes can make patients and families apprehensive to undergo this procedure. The present study aimed at analyzing the results of surgical treatment for RE from a motor and epilepsy standpoint, and mitigate such concerns.

METHODS

Clinical and operative data were retrospectively collected from medical records of pharmacoresistant patients treated with functional hemispherectomy at a tertiary reference center for epilepsy surgery, during a 24-year period (1996-2020). Variables such as age of epilepsy onset, seizure semiology, seizure frequency, immunomodulatory therapy, age at surgery, duration of epilepsy, surgical procedures and complications, number of medications used preoperatively and postoperatively were described and statistically analyzed.

RESULTS

Forty-three (43) patients were included in this study. Mean age of epilepsy onset was 6.14 years, the average interval between epilepsy onset and hemispherotomy was 2.21 years. and the mean age at surgery was 8.28 years. Thirty patients (69.7%) were Engel I at their last follow-up, of whom 23 (56.4%) were Engel Ia, within a mean follow-up of 11.3 years. Duration of epilepsy, seizure frequency, and age at surgery, among others, did not correlate with seizure outcome, except the use of immunotherapy which led to worse outcomes (p < .05). Also, after surgery, motor functionality was significantly recovered (i.e., most patients returned to their previous status) with time.

SIGNIFICANCE

This study tackled some issues regarding the surgical treatment of this disease, particularly showing that hemispherotomy is safe and leads to potentially recoverable disability of motor functions while providing high rates of effective and long-lasting seizure control; therefore, early surgical indication should be warranted once medical refractoriness has been established.

Hemispherotomy Revised: A complication overview and a systematic review meta-analysis

Introduction

Hemispherectomy/hemispherotomy has been employed in the management of catastrophic epilepsy. However, initial reports on the associated mortality and morbidity raised several concerns regarding the technique's safety. Their actual, current incidence needs to be systematically examined to redefine hemispherotomy's exact role.

Research question

Our current study examined their incidence and evaluated the association of the various hemispherotomy surgical techniques with the reported complications.

Material & methods

A PRISMA-compliant systematic review and meta-analysis was performed. We searched PubMed, Scopus, and Web of Science until December 2022. Fixed- and random-effects models were employed. Egger's regression test was used for estimating the publication bias, while subgroup analysis was utilized for defining the role of the different hemispherotomy techniques.

Results

We retrieved a total of 37 studies. The overall procedure mortality was 5%, with a reported mortality of 7% for hemispherectomy and 3% for hemispherotomy. The reported mortality has decreased over the last 30 years from 32% to 2%. Among the observed post-operative complications aseptic meningitis and/or fever occurred in 33%. Hydrocephalus requiring a shunt insertion occurred in 16%. Hematoma evacuation was necessary in 8%, while subgaleal effusion in another 8%. Infections occurred in 11%. A novel post-operative cranial nerve deficit occurred in 11%, while blood transfusion was necessary in 28% of the cases.

Discussion and conclusion

Our current analysis demonstrated that the evolution from hemispherectomy to hemispherotomy along with neuroanesthesia advances, had a tremendous impact on the associated mortality and morbidity. Hemispherotomy constitutes a safe surgical procedure in the management of catastrophic epilepsies.

Health Technology Assessment Report on Vagus Nerve Stimulation in Drug-Resistant Epilepsy

Background: Vagus nerve stimulation (VNS) is a palliative treatment for medical intractable epileptic syndromes not eligible for resective surgery. Health technology assessment (HTA) represents a modern approach to the analysis of technologies used for healthcare. The purpose of this study is to assess the clinical, organizational, financial, and economic impact of VNS therapy in drug-resistant epilepsies and to establish the congruity between costs incurred and health service reimbursement. Methods: The present study used an HTA approach. It is based on an extensive detailed bibliographic search on databases (Medline, Pubmed, Embase and Cochrane, sites of scientific societies and institutional sites). The HTA study includes the following issues: (a) social impact and costs of the disease; (b) VNS eligibility and clinical results; (c) quality of life (QoL) after VNS therapy; (d) economic impact and productivity regained after VNS; and (e) costs of VNS. Results: Literature data indicate VNS as an effective treatment with a potential positive impact on social aspects and on quality of life. The diagnosis-related group (DRG) financing, both on national and regional levels, does not cover the cost of the medical device. There was an evident insufficient coverage of the DRG compared to the full cost of implanting the device. Conclusions: VNS is a palliative treatment for reducing seizure frequency and intensity. Despite its economic cost, VNS should improve patients' quality of life and reduce care needs.

Left hemispherectomy in older children and adolescents: outcome of cognitive abilities

PURPOSE

Hemispherectomy is an effective treatment option for pharmacoresistant epilepsy. Nevertheless, when high cortical functions are at risk during the presurgical evaluation, especially for older children, and for the left hemisphere, despite good seizure outcome, the anticipated decrease of cognitive functions may prevent a decision to perform surgery. The objective of this study is to report the cognitive outcome, based on verbal and performance intelligence skills, in a series of older children and adolescents who underwent left hemispherectomy, analyzing the risks (residual cognitive deficit) and benefits (seizure reduction) of surgery.

METHODS

We retrospectively analyzed pre- and postoperative clinical and neuropsychological data from our patients who underwent left hemispherectomy, aged between 6 and 18 years.

RESULTS

We included 15 patients, with a mean follow-up of 3.1 years, 12 patients (80%) were Engel I, and the other three were classified as Engel II, III, and IV. Nine patients were tested by Wechsler Scales of Intelligence; postsurgically all but one kept the same intellectual levels; verbal intelligence quotient (VIQ) remained unchanged in 13 and improved in one, whereas performance intelligence quotient (PIQ) decreased in four patients. Both Total Vineland and communication scores of Vineland Adaptive Behavior Scales were obtained in six patients: in all, scores were classified as deficient adaptive functioning pre- and postoperatively, remaining unchanged.

CONCLUSION

The evaluation of the remaining intellectual abilities after left hemispherectomy in older children and adolescents is useful to discuss the risks and benefits of this surgery, enabling better and safer decisions regarding surgical indications and timing.

The Dilemma of Hemispherectomy for Rasmussen's Encephalitis in a Neurologically Intact Child

Rasmussen's encephalitis is a rare drug-resistant focal epilepsy characterized by progressive hemiparesis, hemianopia, and cognitive decline. Hemispherectomy is currently the only known treatment that can be curative, though expected to cause postoperative motor and visual deficits in children and adolescents. To date, medical treatment with antiseizure medications and immunosuppressive agents can only offer partial, delayed, or temporary alleviation of symptoms. Hence, patients and families are often faced with the difficult decision to consider the possibility of seizure freedom at the cost of incurring permanent deficits. Here, we discussed the unique ethical issues when faced with a cure that can cause harm, and also discussed a shared decision-making approach guided by informed consent, principles of autonomy, and patient-centered values.

Impact of epilepsy surgery on quality of life and burden of caregivers in children and adolescents

OBJECTIVE

The objective of this study was to analyze the impact of pediatric epilepsy surgery on the quality of life (QOL), determining whether patients improve, worsen, or maintain their preoperative patterns, as it relates to the burden of caregivers, as well as evaluating potential related factors, from both the children and caregivers perspectives.

MATERIAL AND METHODS

This is a retrospective study of children and adolescents who underwent epilepsy surgery and were evaluated through clinical data, videoelectroencephalogram (V-EEG), neuroimaging findings, neuropsychological testing, and aspects of QOL. These assessments were performed prior to surgery and after six months and two years of follow-up. Quality of life was assessed with epilepsy-specialized questionnaires, namely Questionnaire health-related quality of life for children with epilepsy (QVCE-50), Autoquestionnaire Qualité de Vie Enfant Image Scale (AUQUEI), Quality of life in epilepsy inventory for adolescents (QOLEI-AD-48); and burden of caregivers with Burden Interview - ZARIT scale. Postoperative changes in QVCE-50 were quantified using measures of the analysis of variance (ANOVA MR) for comparison of the difference between the three times of the scale and domains.

RESULTS

Fifty patients were enrolled. Of these, 27 (54%) were male, with a mean age at surgery of 8.2 years (range: 1-18 years). Thirty-five patients (70%) were Engel I and one was Engel II (2%) at six months of follow-up, whereas 28 (56%) were Engel I and 32 (64%) were Engel I or II at two years of follow-up. Preoperatively, 21 (42%) presented with moderate or severe intellectual disability. Postoperative cognitive evaluations at the two-year follow-up showed 18 (36%) maintained similar deficits. The QVCE-50 showed postoperative improvement in the two-year follow-up period, but not at six months after surgery. Postoperative improvements were associated mainly with better seizure outcome. Autoperception evaluations were limited because of the clinical and cognitive severity of patients. The burden of caregivers was quoted as mild to moderate and remained unchanged postoperatively.

CONCLUSIONS

Children and adolescents with surgically treated epilepsy reach a good seizure outcome, stabilize in intellectual and adaptive functions, and have an increase in QOL, from the caregiver's perspective. Nevertheless, their burden remains unchanged. Seizure outcome is the main factor for improvement in the QOL. The upgrading of structured questionnaires and QOL instruments specific to pediatric epilepsy can be helpful to assess patient- and caregiver-reported surgical outcomes, allowing for better planning of therapeutic approaches.

Seizure outcomes in children with Rasmussen's encephalitis undergoing resective or hemispheric epilepsy surgery: an individual participant data meta-analysis

OBJECTIVE

The objective of this study was to perform an individual participant data meta-analysis to identify preoperative factors associated with a good seizure outcome in children with Rasmussen's encephalitis (RE) undergoing resective or hemispheric epilepsy surgery.

METHODS

Electronic databases (PubMed, Web of Science, CINAHL) were searched with no language or date restrictions to identify cohort studies of consecutive participants undergoing resective surgery that reported seizure outcomes. The authors recorded all preoperative factors that could plausibly be associated with seizure outcomes and used Cox regression analysis to identify which of these variables were associated with seizure freedom (i.e., Engel class I).

RESULTS

Of 720 citations, 19 articles reporting on 187 participants were eligible. Seizure freedom (Engel class I) was observed in 113 participants (60.4%). On univariate analyses, younger age at disease onset (hazard ratio [HR] 0.906, p = 0.001), younger age at surgery (HR 0.928, p < 0.001), shorter time to surgery (HR 0.921, p = 0.001), and hemispherectomy (HR 0.283, p < 0.001) were all associated with longer time to postoperative seizure recurrence. Additionally, multivariable analysis including the aforementioned variables showed that younger age at surgery (HR 0.946, p = 0.043) and hemispherectomy (HR 0.297, p < 0.001) were independently and significantly associated with a greater time to seizure recurrence and longer duration of seizure freedom.

CONCLUSIONS

The majority of pediatric patients undergoing resective or hemispheric surgery for RE achieve good seizure outcome. Although small retrospective cohort studies are inherently prone to bias, the best available evidence utilizing individual participant data suggests hemispheric surgery and younger age at surgery are associated with good seizure outcomes following epilepsy surgery. Large, multicenter observational studies with long-term follow-up are required to evaluate the risk factors identified in this review.

Pre- and postsurgical cognitive trajectories and quantitative MRI changes in Rasmussen syndrome

OBJECTIVE

To quantify the longitudinal cognitive trajectory, before and after surgery, of Rasmussen syndrome (RS), a rare disease characterized by focal epilepsy and progressive atrophy of one cerebral hemisphere.

METHOD

Thirty-two patients (mean age = 6.7 years; 17 male, 16 left hemispheres affected) were identified from hospital records. The changes in intelligence scores during 2 important phases in the patients' journey to treatment were investigated: (1) during the preoperative period (n = 28, mean follow-up 3.4 years) and (2) from before to after surgery (n = 21 patients, mean time to follow-up 1.5 years). A volumetric magnetic resonance imaging (MRI) analysis of longitudinal changes in gray matter volume was conducted in a subsample of 18 patients.

RESULTS

(1) IQ during the preoperative period: At baseline assessment (on average 2.4 years after seizure onset), the left RS group had lower verbal than nonverbal intellectual abilities, whereas the right group exhibited more difficulties in nonverbal than verbal intellect. Verbal and nonverbal scores declined during the follow-up in both groups, irrespective of the affected side. Hemispheric gray matter volumes declined over time in both groups in affected as well as unaffected hemispheres. (2) Postoperative IQ change: The left surgery group declined further in verbal and nonverbal intellect. The right group's nonverbal intellect declined after surgery, whereas verbal abilities did not. Patients with higher abilities preoperatively experienced large declines, whereas those with poorer abilities showed little change. Postoperative seizures negatively impacted on cognitive abilities.

SIGNIFICANCE

During the chronic phase of the disease, parallel decline of verbal and nonverbal abilities suggest progressive bilateral hemispheric involvement, supported by evidence from MRI morphometry. Postsurgical cognitive losses are predicted by greater presurgical ability and continuing seizures. A shorter duration from seizure onset to surgery could reduce the postoperative cognitive burden by minimizing the decline in functions supported by the unaffected hemisphere.

Surgical treatment for refractory epilepsy

The goal of any epilepsy surgery is to improve patient's quality of life by achieving seizure freedom or by reducing the frequency of severely debilitating seizures. To achieve this goal, non-invasive and invasive diagnostic methods must precisely delineate the epileptogenic zone (EZ), which is defined as the area that needs to be resected to obtain seizure freedom. At the same time, the correct identification of eloquent brain areas is inevitable to avoid new neurological deficits from surgery. In recent years, the technical advances in diagnostics have enabled us to achieve these goals in an increasing number of cases. As a consequence, and with new surgical treatment options available, the number of patients who might benefit from epilepsy surgery is constantly increasing. Especially in pediatric epilepsy, early surgical intervention is becoming frequently advocated as it has been shown to improve cognitive and behavioral outcome. Specialized epilepsy centers and multidisciplinary teams are required to provide adequate care and treatment. The goal of this review is to describe important diseases that are accessible to epilepsy surgery and to give an overview of current diagnostic methods. The focus lies on established as well as novel techniques in epilepsy surgery. The presurgical work-up and patient selection is outlined.

Language recovery after left hemispherotomy for Rasmussen encephalitis

PURPOSE

Hemispherotomy (H) is the gold standard treatment to cure epilepsy in Rasmussen encephalitis (RE). Linguistic prognosis after surgery remains the main issue when the dominant hemisphere is involved. The topic of the present research is to specify the long-term linguistic profile of the right hemisphere after left dominant H for RE.

METHODS

We followed 6 children 8.4 to 14.6 years of age who underwent left H for RE. Preoperatively, four children experienced aphasia, but for two, worsening occurred after surgery. Age at H ranged from 4.1 to 8.4 years. The mean duration of epilepsy was 1.2 years and 5.6 years for follow-up. Neuropsychological evaluation included longitudinal follow-up of intellectual efficiency measurement and a long-term outcome of language using various components of receptive and expressive oral speech with computerized tasks.

KEY FINDINGS

Preoperatively, verbal comprehension index (VCI) was dramatically decreased in 4/6 patients, and performance reasoning index (PRI) was low in 5/6 participants, demonstrating a global impact of RE itself. Postoperatively, all children recovered sufficiently to attend a regular VCI (above 70) in a mean of 5 years after H, and 5/6 recovered normal or adapted school. There was a dissociation in favor of VCI, while PRI decreased in 5/6 patients. We found a specific linguistic profile for these children recovering language in the right hemisphere: normal verbal comprehension, and weakness of grammatical judgment, word repetition, statement production, semantic verbal fluency and metaphonological abilities. Language recovery scores were statistically correlated with those of Working Memory Index.

SIGNIFICANCE

This study emphasizes for the first time the ability of the right hemisphere to functionally reorganize language over a long period of time following left H for RE. Syntactic abilities and phonology remain low and support the hypothesis of an early left hemispheric specialization. Nevertheless, lexico-semantic processes recover in the right hemisphere that could reflect a pre-existing potential of both hemispheres. Our results support a decision to proceed to H in classical left RE disease until the late childhood even if there is no complete aphasia before surgery. These data should be taken in account in the overall postoperative follow-up and rehabilitation strategy.

Rasmussen's encephalitis: A case report

Rasmussen's encephalitis (RE) is a rare neurological disorder of inflammatory aetiology characterised by encephalitis, intractable seizures, hemiparesis, variable motor deficits, and dementia. It is not commonly considered in the clinical differential diagnosis of a patient with a past history of a stroke-like episode presenting with status epilepticus. It is suspected mainly in children in whom the disease is more common. Here we report a case of an adult man presenting with a common symptom of seizure caused by Rasmussen's encephalitis.

Hemispherotomy in Rasmussen encephalitis: long-term outcome in an Italian series of 16 patients

Surgical disconnection of the affected hemisphere is considered the treatment of choice for Rasmussen encephalitis (RE), however few data on long-term outcomes after disconnective surgery are available. We report on long-term seizure, cognitive and motor outcomes after disconnective surgery in 16 (8 M, 8 F) RE patients. Pre- and post-operative evaluations included long-term video-EEG monitoring, MRI, assessment of motor function, and cognitive evaluation. Hemispherotomy, by various techniques was used to obtain functional disconnection of the affected hemisphere. The patients, of median current age 23.5 years, range 12-33, were operated on between 1993 and 2009. Median age at disease onset was 5.8 years (range 3-11.4). Median time from seizure onset to surgery was 3.8 years, range 8 months to 21 years. Post-surgical follow-up was a median of 9.5 years, range 3-20. At surgery all patients were receiving two or more antiepileptic drugs (AEDs). All but three patients were seizure-free at latest follow-up. AEDs had been stopped in ten patients; in the remaining six AEDs were markedly reduced. Postural control improved in all patients. Gain in cognitive functioning was significantly (p=0.002) related to disease duration. The long-term outcomes, in terms of seizure control, motor improvement, and cognitive improvement provide important support for disconnective surgery as first choice treatment for RE.

Epilepsy surgery series: a study of 502 consecutive patients from a developing country

Purpose. To review the postoperative seizure outcomes of patients that underwent surgery for epilepsy at King Faisal Specialist Hospital & Research Centre (KFSHRC). Methods. A descriptive retrospective study for 502 patients operated on for medically intractable epilepsy between 1998 and 2012. The surgical outcome was measured using the ILAE criteria. Results. The epilepsy surgery outcome for temporal lobe epilepsy surgery (ILAE classes 1, 2, and 3) at 12, 36, and 60 months is 79.6%, 74.2%, and 67%, respectively. The favorable 12- and 36-month outcomes for frontal lobe epilepsy surgery are 62% and 52%, respectively. For both parietal and occipital epilepsy lobe surgeries the 12- and 36-month outcomes are 67%. For multilobar epilepsy surgery, the 12- and 36-month outcomes are 65% and 50%, respectively. The 12- and 36-month outcomes for functional hemispherectomy epilepsy surgery are 64.2% and 63%, respectively. According to histopathology diagnosis, mesiotemporal sclerosis (MTS) and benign CNS tumors had the best favorable outcome after surgery at 1 year (77.27% and 84.3%, resp.,) and 3 years (76% and 75%, resp.,). The least favorable seizure-free outcome after 3 years occurred in cases with dual pathology (66.6%). Thirty-four epilepsy patients with normal magnetic resonance imaging (MRI) brain scans were surgically treated. The first- and third-year epilepsy surgery outcome of 17 temporal lobe surgeries were (53%) and (47%) seizure-free, respectively. The first- and third-year epilepsy surgery outcomes of 15 extratemporal epilepsy surgeries were (47%) and (33%) seizure-free. Conclusion. The best outcomes are achieved with temporal epilepsy surgery, mesial temporal sclerosis, and benign CNS tumor. The worst outcomes are from multilobar surgery, dual pathology, and normal MRI.

Vagus nerve stimulation in refractory epilepsy: new indications and outcome assessment

Although vagus nerve stimulation (VNS) is an effective alternative option for patients with refractory epilepsy unsuitable for conventional resective surgery, predictors of a better control of seizure frequency and severity are still unavailable. This prospective study reports on 39 patients, including 4 children affected by epilepsia partialis continua (EPC), who underwent VNS for refractory epilepsy. The overall seizure frequency outcome was classified into three groups according to reduction rate: ≥75%, ≥50%, and <50%. Engel and McHugh classifications were also used. The median follow-up period was 36months. A seizure reduction rate ≥50% or EPC improvement was observed in 74% of the patients. Twenty-one out of 35 cases (60%) resulted in Engel classes II and III. Outcome, as defined by the McHugh scale, showed a responder rate of 71%. These results suggest that younger patient age and focal or multifocal epilepsy are related to a better seizure control and cognitive outcome. Vagus nerve stimulation could also be considered as an effective procedure in severe conditions, such as drug-refractory EPC.

Seizure and developmental outcomes after hemispherectomy in children and adolescents with intractable epilepsy

PURPOSE

The aim of this study is to describe a series of pediatric hemispherectomies, reviewing pathologic substrate, epilepsy characteristics and seizure outcome as well as developmental profiles, before and after surgery, in different domains.

METHODS

Seventeen patients with full pre-surgical work-up, minimum follow-up of 12 months, and at least one post-surgical neuropsychological evaluation were selected. Three had Rasmussen encephalitis (RE), five hemispheric malformations of cortical development (MCD), and nine hemispheric vascular lesions.

RESULTS

At latest follow-up, all patients with RE and 66.7 % of those with vascular lesions are in Engel's class I; in the latter group, pre-surgical independent contralateral EEG discharges statistically correlated with a worse seizure outcome. Patients with MCD showed the worst seizure outcome. Pre-surgical language transfer to the right hemisphere was confirmed in a boy with left RE, operated on at 6 years of age. Patients with MCD and vascular lesions already showed severe global developmental delay before surgery, which persists afterwards. A linear correlation was found between earlier age at surgery and better outcome in personal-social, gross motor, and adaptive domains, in the vascular lesions group. The case with highest cognitive improvement had continuous spike and wave during sleep on pre-surgical EEG.

CONCLUSIONS

Pathologic substrate was the main factor related with seizure outcome. In children with MCD and vascular lesions, although developmental progression is apparent, significant post-surgical improvements are restricted by the severity of pre-surgical neuropsychological disturbances and a slow maturation. Early surgery assessment is recommended to enhance the possibilities for a better quality of life in terms of seizure control, as well as better autonomy and socialization.