Health Technology Assessment report on the presurgical evaluation and surgical treatment of drug-resistant epilepsy

Socio-economic impact of epilepsy in Italy

The World Health Assembly recognizes the growing economic and societal burden of neurological disorders, a leading cause of disability and the second cause of mortality in the world. In this context we analysed the socio-economic impact of epilepsy in Italy with a specific focus on hospitalizations and costs related to disability pensions (DPs) and ordinary disability allowances. In the case of epilepsy, between 2009 and 2015 we observed an alarming increasing trend for DPs (+26%), indicating that substantial expenses must be supported throughout the patients' lifetimes by both the social security system and the National Health Service (NHS) on top of the impact on caregivers. We also analysed the hospital expenditure on epilepsy through the information available in the Hospital Discharge Cards between 2015 and 2018. Almost all admissions (76% ordinary hospitalizations, 24% day hospitals) were acute (95%), followed by rehabilitation (4%) and long-term care (1%). The cost of acute and ordinary hospitalizations was by far the highest in 2018, the last year of analysis. This large expense due to hospitalizations could be reduced through the implementation of different organizational and management approaches. Our recommendation is that the policy maker should consider the best approach to ensure an early diagnosis for patients and provide early access to drugs and/or surgery. Finally, the adoption of new innovative treatments should improve effectiveness and, at the same time, reduce the expense of the NHS, of the social system as a whole, with a tangible improvement in patients' quality of life.

Interpretable EEG seizure prediction using a multiobjective evolutionary algorithm

Seizure prediction might be the solution to tackle the apparent unpredictability of seizures in patients with drug-resistant epilepsy, which comprise about a third of all patients with epilepsy. Designing seizure prediction models involves defining the pre-ictal period, a transition stage between inter-ictal brain activity and the seizure discharge. This period is typically a fixed interval, with some recent studies reporting the evaluation of different patient-specific pre-ictal intervals. Recently, researchers have aimed to determine the pre-ictal period, a transition stage between regular brain activity and a seizure. Authors have been using deep learning models given the ability of such models to automatically perform pre-processing, feature extraction, classification, and handling temporal and spatial dependencies. As these approaches create black-box models, clinicians may not have sufficient trust to use them in high-stake decisions. By considering these problems, we developed an evolutionary seizure prediction model that identifies the best set of features while automatically searching for the pre-ictal period and accounting for patient comfort. This methodology provides patient-specific interpretable insights, which might contribute to a better understanding of seizure generation processes and explain the algorithm’s decisions. We tested our methodology on 238 seizures and 3687 h of continuous data, recorded on scalp recordings from 93 patients with several types of focal and generalised epilepsies. We compared the results with a seizure surrogate predictor and obtained a performance above chance for 32% patients. We also compared our results with a control method based on the standard machine learning pipeline (pre-processing, feature extraction, classifier training, and post-processing), where the control marginally outperformed our approach by validating 35% of the patients. In total, 54 patients performed above chance for at least one method: our methodology or the control one. Of these 54 patients, 21 (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\approx$$\end{document}≈38%) were solely validated by our methodology, while 24 (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\approx$$\end{document}≈44%) were only validated by the control method. These findings may evidence the need for different methodologies concerning different patients.

[Modified posterior quadrant disconnection in surgical treatment of drug-resistant epilepsy in a patient with left temporal and occipital lobe malformation]

Adults with large multilobar lesions of temporal, parietal and occipital lobes of the dominant hemisphere suffering from drug-resistant epilepsy were considered inoperable for a long time.

OBJECTIVE

To demonstrate favorable postoperative outcome in a patient with massive periventricular heterotopia of the left temporal and occipital lobes complicated by drug-resistant epilepsy.

MATERIAL AND METHODS

We analyzed localization of the brain malformation (massive periventricular heterotopia) and its relationship with surrounding structures in a 38-year-old patient considering preoperative MRI, functional MRI and MR tractography data. Quality of modified posterior quadrant disconnection was assessed within a day and 6 months after surgery in accordance with MRI data. Transcranial stimulation, direct cortical and subcortical monopolar stimulation were used for intraoperative monitoring of corticospinal tract. We also assessed neurological status and linguistic testing data before surgery, 4 days and 6 months after surgery.

RESULTS

Modified posterior disconnection of temporal, parietal and occipital lobes was performed. Intraoperative neurophysiological cortical mapping (asleep-awake-sedation protocol) verified localization of Wernicke's area. There was an expected right-sided homonymous hemianopsia in postoperative period without speech disorders. Postoperative outcome Engel grade 1A under anticonvulsant therapy was obtained.

CONCLUSION

The authors report successful surgical treatment of massive malformation of the left temporal, parietal and occipital lobes and literature review devoted to this issue.

The 50th anniversary of the Italian League Against Epilepsy (Lega Italiana Contro l’Epilessia)

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We describe the 50-year history of the Italian League Against Epilepsy (LICE).

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LICE promotes high-quality epilepsy care, education and research into epilepsy.

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LICE maintains close relations with ILAE and other professional societies.

This article was prepared to outline the article collection submitted on behalf of Lega Italiana Contro l’Epilepsia, or LICE, for the 50th anniversary of the founding of the ILAE Italian Chapter, and provides a brief summary of the history, with its landmark achievements and challenges. LICE is a multidisciplinary, inclusive, educational, informative and multifaceted organization. Initially in 1955 and then formally in 1972, LICE was born in Milano, with the mission to devote itself to people suffering with epilepsy and by promoting appropriate treatment and care, integration into society, to promote and pursue all kinds of activities designed to achieve those aims. The LICE is currently composed of more than 1000 members including neurologists, pediatric neurologists, neurosurgeons, neurophysiologists, and neuropsychologists who function throughout Italy dealing mainly or exclusively with the diagnosis and treatment of people with epilepsy.

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.

Identifying the epileptogenic zone by four non-invasive imaging techniques versus stereo-EEG in MRI-negative pre-surgery epilepsy patients

OBJECTIVE

We evaluated four imaging techniques, i.e. Electroencephalography (EEG)-functional Magnetic Resonance Imaging (MRI) (EEG-fMRI), High-resolution EEG (HR-EEG), Magnetoencephalography (MEG) and 2-[18F]fluoro-2-deoxy-D-glucose positron emission tomography (PET), for the identification of the epileptogenic zone (EZ) in 41 patients with negative MRI, candidate to neurosurgery.

METHODS

For each technique, results were compared to the Stereo-EEG. Diagnostic measures were calculated with respect to the post-surgical outcome, either for all the patients (39/41, two patients excluded) and for the subgroup of patients with the EZ involving more than one lobe (20/41).

RESULTS

When considered individually, each functional technique showed accuracy values ranging 54,6%-63,2%, having PET, MEG and HR-EEG higher sensitivity, and EEG-fMRI higher specificity. In patients with multilobar epileptogenic zone, functional techniques achieved the best accuracies (up to 80%) when three techniques, including EEG-fMRI, were considered together.

CONCLUSIONS

The study highlights the accuracy of a combination of functional imaging techniques in the identification of EZ in MRI negative focal epilepsy. The best diagnostic yield was obtained if the combination of PET, MEG (or HR-EEG as alternative), EEG-fMRI were considered together.

SIGNIFICANCE

The functional imaging techniques may improve the presurgical workup of MRI negative focal epilepsy, if epileptogenic zone involves more than one lobe.

Methodology, outcome, safety and in vivo accuracy in traditional frame-based stereoelectroencephalography

Background

Stereoelectroencephalography (SEEG) is an established diagnostic technique for the localization of the epileptogenic zone in drug-resistant epilepsy. In vivo accuracy of SEEG electrode positioning is of paramount importance since higher accuracy may lead to more precise resective surgery, better seizure outcome and reduction of complications.

Objective

To describe experiences with the SEEG technique in our comprehensive epilepsy center, to illustrate surgical methodology, to evaluate in vivo application accuracy and to consider the diagnostic yield of SEEG implantations.

Methods

All patients who underwent SEEG implantations between September 2008 and April 2016 were analyzed. Planned electrode trajectories were compared with post-implantation trajectories after fusion of pre- and postoperative imaging. Quantitative analysis of deviation using Euclidean distance and directional errors was performed. Explanatory variables for electrode accuracy were analyzed using linear regression modeling. The surgical methodology, procedure-related complications and diagnostic yield were reported.

Results

Seventy-six implantations were performed in 71 patients, and a total of 902 electrodes were implanted. Median entry and target point deviations were 1.54 mm and 2.93 mm. Several factors that predicted entry and target point accuracy were identified. The rate of major complications was 2.6%. SEEG led to surgical therapy of various modalities in 53 patients (69.7%).

Conclusions

This study demonstrated that entry and target point localization errors can be predicted by linear regression models, which can aid in identification of high-risk electrode trajectories and further enhancement of accuracy. SEEG is a reliable technique, as demonstrated by the high accuracy of conventional frame-based implantation methodology and the good diagnostic yield.

Pregnane X Receptor Not Nuclear Factor-kappa B Up-regulates P-glycoprotein Expression in the Brain of Chronic Epileptic Rats Induced by Kainic Acid

Drug-resistance epilepsy (DRE) is attributed to the brain P-glycoprotein (P-gp) overexpression. We previously reported that nuclear factor-kappa B (NF-κB) played a critical role in regulating P-gp expression at the brain of the acute seizure rats. This study was extended further to investigate the interaction effect of NF-κB and pregnane X receptor (PXR) on P-gp expression at the brain of chronic epileptic rats treated with carbamazepine (CBZ). The chronic epileptic models were induced by the micro-injection of kainic acid (KA) into rats' hippocampus. Subsequently, the successful models were treated with different intervention agents of CBZ; PMA(a non-specific PXR activity inhibitor) or PDTC(a specific NF-κB activity inhibitor) respectively. The expression levels of P-gp and its encoded gene mdr1a/b were significantly up-regulated on the brain of KA-induced chronic epilepsy rats or the epilepsy rats treated with CBZ for 1 week, meanwhile with a high expression of PXR. The treatment of PMA dramatically reduced both PXR and P-gp expressions at the protein and mRNA levels in the chronic epilepsy brain. By compared to the epilepsy model group, the P-gp expression was not markedly attenuated by the inhibition of NF-κB activity with PDTC treatment, nevertheless with a decrease of NF-κB expression in this intervention group. Higher levels of proinflammatory cytokines(IL-1β, IL-6, TNF-α) were found both in the brain tissue and the serum in the epilepsy rats of each group. There was a declined trend of the pro-inflammatory cytokines expression of the PDTC treatment group but with no statistical significance. This study demonstrates for the first time that P-gp up-regulation is due to increase PXR expression in the chronic phase of epilepsy, differently from that NF-κB signaling may induce the P-gp expression in the acute seizure phase. Our results offer insights into the mechanism underlying the development of DRE using or not using CBZ treatment.