Inequities in access to pediatric epilepsy surgery: a bioethical framework

Connectomic profiling and Vagus nerve stimulation Outcomes Study (CONNECTiVOS): a prospective observational protocol to identify biomarkers of seizure response in children and youth

INTRODUCTION

Vagus nerve stimulation (VNS) is a neuromodulation therapy that can reduce the seizure burden of children with medically intractable epilepsy. Despite the widespread use of VNS to treat epilepsy, there are currently no means to preoperatively identify patients who will benefit from treatment. The objective of the present study is to determine clinical and neural network-based correlates of treatment outcome to better identify candidates for VNS therapy.

METHODS AND ANALYSIS

In this multi-institutional North American study, children undergoing VNS and their caregivers will be prospectively recruited. All patients will have documentation of clinical history, physical and neurological examination and video electroencephalography as part of the standard clinical workup for VNS. Neuroimaging data including resting-state functional MRI, diffusion-tensor imaging and magnetoencephalography will be collected before surgery. MR-based measures will also be repeated 12 months after implantation. Outcomes of VNS, including seizure control and health-related quality of life of both patient and primary caregiver, will be prospectively measured up to 2 years postoperatively. All data will be collected electronically using Research Electronic Data Capture.

ETHICS AND DISSEMINATION

This study was approved by the Hospital for Sick Children Research Ethics Board (REB number 1000061744). All participants, or substitute decision-makers, will provide informed consent prior to be enrolled in the study. Institutional Research Ethics Board approval will be obtained from each additional participating site prior to inclusion. This study is funded through a Canadian Institutes of Health Research grant (PJT-159561) and an investigator-initiated funding grant from LivaNova USA (Houston, TX; FF01803B IIR).

Transformer-Based High-Frequency Oscillation Signal Detection on Magnetoencephalography From Epileptic Patients

High-frequency oscillations (HFOs), observed within 80–500 Hz of magnetoencephalography (MEG) data, are putative biomarkers to localize epileptogenic zones that are critical for the success of surgical epilepsy treatment. It is crucial to accurately detect HFOs for improving the surgical outcome of patients with epilepsy. However, in clinical practices, detecting HFOs in MEG signals mainly depends on visual inspection by clinicians, which is very time-consuming, labor-intensive, subjective, and error-prone. To accurately and automatically detect HFOs, machine learning approaches have been developed and have demonstrated the promising results of automated HFO detection. More recently, the transformer-based model has attracted wide attention and achieved state-of-the-art performance on many machine learning tasks. In this paper, we are investigating the suitability of transformer-based models on the detection of HFOs. Specifically, we propose a transformer-based HFO detection framework for biomedical MEG one-dimensional signal data. For signal classification, we develop a transformer-based HFO (TransHFO) classification model. Then, we investigate the relationship between depth of deep learning models and classification performance. The experimental results show that the proposed framework outperforms the state-of-the-art HFO classifiers, increasing classification accuracy by 7%. Furthermore, we find that shallow TransHFO (< 10 layers) outperforms deep TransHFO models (≥10 layers) on most data augmented factors.

Development of a Pediatric Epilepsy Program: Analysis of Early Multidimensional Outcomes

Background A Pediatric Epilepsy Program was instituted in Manitoba in 2016. This report seeks to describe changes in the management of pediatric epilepsy patients in Manitoba since the inception of this Program, to provide an early analysis of local outcomes, and to present a framework for further program development.

Methods Data was collected for patients treated both before and after inception of the Program. Caregivers completed questionnaires on quality of life and program satisfaction. An online database was created to capture demographic information, seizure and quality of life outcomes, and caregiver satisfaction ratings. Descriptive statistics were used to summarize the results.

Results Prior to commencement of the Program, 16 patients underwent vagal nerve stimulator (VNS) insertion. At last follow-up, 6.25% of patients achieved Engel class I outcome, 75% achieved class III outcome, and 18.75% were classified as class IV. Following inception of the Program, 11 patients underwent resective procedures and 3 underwent VNS insertions. At last follow-up, 78.6% of patients achieved Engel class I outcome, 14.3% achieved class III outcome, and 7.1% were classified as class IV. Since inception of the Program, the average Quality of Life in Childhood Epilepsy Questionnaire-55 score measuring patient quality of life was (59.7 ± 23.2)/100. The average Care-Related Quality of Life-7D score measuring caregiver quality of life was (78.3 ± 18.6)/100. Caregiver satisfaction had an average rating of (9.4 ± 0.8)/10.

Conclusion Access to epilepsy surgery has significantly improved for children in Manitoba and has led to favorable, early multidimensional outcomes. Structural organization, funding, and multidisciplinary engagement are necessary for program sustainability and growth.

Ethical considerations in the surgical and neuromodulatory treatment of epilepsy

Surgical resection and neuromodulation are well-established treatments for those with medically refractory epilepsy. These treatments entail important ethical considerations beyond those which extend to the treatment of epilepsy generally. In this paper, the authors explore these unique considerations through a framework that relates foundational principles of bioethics to features of resective epilepsy surgery and neuromodulation. The authors conducted a literature review to identify ethical considerations for a variety of epilepsy surgery procedures and to examine how foundational principles in bioethics may inform treatment decisions. Healthcare providers should be cognizant of how an increased prevalence of somatic and psychiatric comorbidities, the dynamic nature of symptom burden over time, the individual and systemic barriers to treatment, and variable sociocultural contexts constitute important ethical considerations regarding the use of surgery or neuromodulation for the treatment of epilepsy. Moreover, careful attention should be paid to how resective epilepsy surgery and neuromodulation relate to notions of patient autonomy, safety and privacy, and the shared responsibility for device management and maintenance. A three-tiered approach-(1) gathering information and assessing the risks and benefits of different treatment options, (2) clear communication with patient or proxy with awareness of patient values and barriers to treatment, and (3) long-term decision maintenance through continued identification of gaps in understanding and provision of information-allows for optimal treatment of the individual person with epilepsy while minimizing disparities in epilepsy care.

Underrepresented Populations in Pediatric Epilepsy Surgery

As awareness of pediatric epilepsy increases, accompanied by advancements in technology and research, it is important to identify certain types of patients that are overlooked for surgical management of epilepsy. Identifying these populations will allow us to study and elucidate the factors contributing to the underutilization and/or delayed application of surgical interventions. Demographically, African-American and Hispanic patients, as well as patients of certain Asian ethnicities, have relatively lower rates of undergoing epilepsy surgery than non-Hispanic and white patients. Among patients with epilepsy, those with higher odds of seizure-freedom following surgery are more likely to be referred for surgical evaluation by their neurologists, with the most common diagnosis being lesional focal epilepsy. However, patients with multifocal or generalized epilepsy, genetic etiologies, or normal (non-lesional) brain magnetic resonance imaging (MRI) are less likely be to referred for evaluation for resective surgery. With an increasing number of high-quality imaging modalities to help localize the epileptogenic zone as well as new techniques for both curative and palliative epilepsy surgery, there are very few populations of patients and/or types of epilepsy that should be precluded from evaluation to determine the suitability of epilepsy surgery. Ultimately, a clearer understanding of the populations who are underrepresented among those considered for epilepsy surgery, coupled with further study of the underlying reasons for this trend, will lead to less disparity in access to this critical treatment among patients with epilepsy.

Epilepsy Surgery in Children

Epilepsy in children continues to present a major medical and economic burden on society. Left untreated, seizures can present the risk of sudden death and severe cognitive impairment. It is understood that primary care providers having concerns about abnormal movements or behaviors in children will make a prompt referral to a trusted pediatric neurologist. The authors present a brief introduction to seizure types, classification, and management with particular focus on what surgery for epilepsy can offer. Improved seizure control and its attendant improvements in quality of life can be achieved with timely referral and intervention.

From vision to action: Canadian leadership in ethics and neurotechnology

This chapter explores the complex neuroethical aspects of neurosurgery and neuromodulation in the context of Canadian healthcare and innovation, as seen through the lens of the Pan Canadian Neurotechnology Ethics Consortium (PCNEC). Highlighted are key areas of ethical focus, each with its own unique challenges: technical advances, readiness and risk, vulnerable populations, medico-legal issues, training, and research. Through an exploration of Canadian neurotechnological practice from these various clusters, we provide a critical review of progress, describe opportunities to address areas of debate, and seek to foster ethical innovation. Underpinning this comprehensive review are the fundamental principles of solution-oriented, practical neuroethics, with beneficence and justice at the core. In our view, it is a moral imperative that neurotechnological advancements include a delineation of ethical priorities for future guidelines, oversight, and interactions.

Automatic and Accurate Epilepsy Ripple and Fast Ripple Detection via Virtual Sample Generation and Attention Neural Networks

About 1% of the population around the world suffers from epilepsy. The success of epilepsy surgery depends critically on pre-operative localization of epileptogenic zones. High frequency oscillations including ripples (80-250 Hz) and fast ripples (250-500 Hz) are commonly used as biomarkers to localize epileptogenic zones. Recent literature demonstrated that fast ripples indicate epileptogenic zones better than ripples. Thus, it is crucial to accurately detect fast ripples from ripples signals of magnetoencephalography for improving outcome of epilepsy surgery. This paper proposes an automatic and accurate ripple and fast ripple detection method that employs virtual sample generation and neural networks with an attention mechanism. We evaluate our proposed detector on patient data with 50 ripples and 50 fast ripples labeled by two experts. The experimental results show that our new detector outperforms multiple traditional machine learning models. In particular, our method can achieve a mean accuracy of 89.3% and an average area under the receiver operating characteristic curve of 0.88 in 50 repeats of random subsampling validation. In addition, we experimentally demonstrate the effectiveness of virtual sample generation, attention mechanism, and architecture of neural network models.

Epilepsy surgery in low- and middle-income countries: A scoping review

BACKGROUND

Epilepsy surgery is an important treatment option for people with drug-resistant epilepsy. Surgical procedures for epilepsy are underutilized worldwide, but it is far worse in low- and middle-income countries (LMIC), and it is less clear as to what extent people with drug-resistant epilepsy receive such treatment at all. Here, we review the existing evidence for the availability and outcome of epilepsy surgery in LMIC and discuss some challenges and priority.

METHODS

We used an accepted six-stage methodological framework for scoping reviews as a guide. We searched PubMed, Embase, Global Health Archives, Index Medicus for South East Asia Region (IMSEAR), Index Medicus for Eastern Mediterranean Region (IMEMR), Latin American & Caribbean Health Sciences Literature (LILACS), African Journal Online (AJOL), and African Index Medicus (AIM) to identify the relevant literature.

RESULTS

We retrieved 148 articles on epilepsy surgery from 31 countries representing 22% of the 143 LMIC. Epilepsy surgery appears established in some of these centers in Asia and Latin America while some are in their embryonic stage reporting procedures in a small cohort performed mostly by motivated neurosurgeons. The commonest surgical procedure reported was temporal lobectomies. The postoperative seizure-free rates and quality of life (QOL) are comparable with those in the high-income countries (HIC). Some models have shown that epilepsy surgery can be performed within a resource-limited setting through collaboration with international partners and through the use of information and communications technology (ICT). The cost of surgery is a fraction of what is available in HIC.

CONCLUSION

This review has demonstrated the availability of epilepsy surgery in a few LMIC. The information available is inadequate to make any reasonable conclusion of its existence as routine practice. Collaborations with international partners can provide an opportunity to bring high-quality academic training and technological transfer directly to surgeons working in these regions and should be encouraged.

A screening tool to identify surgical candidates with drug refractory epilepsy in a resource limited settings

OBJECTIVES

Access to epilepsy surgery remains a considerable challenge in contemporary healthcare systems. Given the limitations in resources and demand for Epilepsy Monitoring Unit (EMU) assessments, information that can be used to expedite the process is of great value. The purpose of this study was to identify variables prior to EMU admission that may be associated with candidacy for prospective epilepsy surgery.

METHODS

This was a prospective study conducted at the Department of Neurology, All India Institute of Medical Sciences, New Delhi, India. We identified two subgroups of patients from 501 drug refractory epilepsy (DRE) patients admitted in EMU of Neurology Department, AIIMS from 2006 onwards following validation of proposed tool in 40 patients. They on subsequent investigations were either cleared or not cleared for epilepsy surgery. A tool consisting of variables likely to predict surgical candidacy in persons with DRE in Indian settings was developed for identification of patients who might benefit from an early epilepsy surgery evaluation.

RESULTS

Statistical analysis revealed significant differences between the two groups for several variables. Non-surgical candidates had non-disabling seizures, seizures improved with a combination of drugs, had little/no AEDs side effects and had near normal or normal scalp EEG and MRI brain.

SIGNIFICANCE

Using the best available evidence, we developed a decision making tool which can provide a comprehensive quick guide for determining candidacy for epilepsy surgery evaluations in resource limited settings. Given the demand for EMU assessments, information that can be used to expedite the process is of value.

Predictors of Surgical Candidacy in 414 Epilepsy Patients Admitted to the EMU

Objectives:

Admission to an Epilepsy Monitoring Unit (EMU) is essential for pre-surgical evaluation of patients with medically-refractory epilepsy; however, prolonged referral times and resource limitations are significant access barriers. Therefore, identification of pre-EMU variables that predict potential surgical candidates can assist in the triage of patient admissions to the EMU.

Methods:

In this hypothesis-generating study, a retrospective analysis of patients admitted for pre-surgical evaluation to the Toronto Western Hospital EMU (2004-2011) was performed. Univariate and multivariate logistic regression was used to identify variables that could independently predict subsequent surgical candidacy following EMU evaluation.

Results:

Four hundred and fourteen patients were admitted to the EMU. Overall, 259 patients (62.5%) were identified as potential surgical candidates. One hundred and seven patients (25.8%) required invasive electroencephalogram (iEEG) implantations; of 75 patients consenting to iEEG analysis 39 underwent a subsequent resective procedure. Male patients and those with a lesion on MRI were 1.9 times more likely to be surgical candidates (95% CI 1.18-2.98 and 0.94-3.80, respectively), while patients with non-localizable seizures were seven times less likely (95% CI 0.02-1.25).

Conclusion:

In this retrospective, hypothesis-generating study male gender, presence of a lesion on MRI and localizable seizures on routine outpatient EEG analysis independently predicted subsequent resective epilepsy surgical candidacy in EMU patients. Upon validation by other studies, these variables may be considered by clinicians referring patients to the EMU in order to improve wait times and optimize patient care.

Priority setting in neurosurgery as exemplified by an everyday challenge

BACKGROUND

The allocation of limited healthcare resources poses a constant challenge for clinicians. One everyday example is the prioritization of elective neurosurgical operating room (OR) time in circumstances where cancellations may be encountered. The bioethical framework, Accountability for Reasonableness (A4R) may inform such decisions by establishing conditions that should be met for ethically-justifiable priority setting.

OBJECTIVE

Here, we describe our experience in implementing A4R to guide decisions regarding elective OR prioritization.

METHODS

The four primary expectations of the A4R process are: (1) relevance, namely achieved by support for the process and criteria for decisions amongst all stakeholders; (2) publicity, satisfied by the effective communication of the results of the deliberation; (3) challengeability through a fair appeals process; and (4) Oversight of the process to ensure that opportunities for its improvement are available.

RESULTS

A4R may be applied to inform OR time prioritization, with benefits to patients, surgeons and the institution itself. We discuss various case-, patient-, and surgeon-related factors that may be incorporated into the decision-making process. Furthermore, we explore challenges encountered in the implementation of this process, including the need for timely neurosurgical decision-making and the presence of hospital-based power imbalances.

CONCLUSION

The authors recommend the implementation of a fair, deliberative process to inform priority setting in neurosurgery, as demonstrated by the application of the A4R framework to allocate limited OR time.

Changing global trends in seizure outcomes following resective surgery for tuberous sclerosis in children with medically intractable epilepsy

Introduction. Tuberous sclerosis (TS) is the leading cause of genetic epilepsy worldwide. Here, we evaluate changes in seizure outcomes following resective epilepsy surgery in children with TS over time. Methods. A systematic review of the literature was performed to identify studies reporting seizure outcomes following resective epilepsy surgery in children with TS. Using an individual participant meta-analysis approach, seizure outcomes and associated covariates were combined. Multivariate logistic regression was used to determine significant associations between seizure outcomes and time of surgery. Results. Twenty studies from 1966 to present, yielding 186 participants, met the inclusion criteria for the study. On univariate analysis, there was a significant improvement in seizure outcomes in children who underwent resective epilepsy surgery within the last 15 years compared to older cohorts (chi-square 4.1; P = 0.043). On multivariate analysis, adjusting for length of followup, this trend was not significant (OR 0.52; 95% CI 0.23–1.17; P = 0.11). In the last 15 years, a greater proportion of younger children also underwent resective surgery compared to older cohorts (OR 0.93; 95% CI 0.89–0.97; P < 0.01). Conclusions. A trend towards improved seizure outcomes following resective surgery for TS was observed from 1966 to present on multivariate analysis.