Thalamocortical Hodology to Personalize Electrical Stimulation for Focal Epilepsy.

Targeted electrical stimulation to specific thalamic regions offers a therapeutic approach for patients with refractory focal and generalized epilepsy who are not candidates for resective surgery. However, clinical outcome varies significantly, in particular for focal epilepsy, influenced by several factors, notably the precise anatomical and functional alignment between cortical regions generating epileptic discharges and the targeted thalamic stimulation sites. Here we hypothesized that targeting thalamic nuclei with precise anatomical and functional connections to epileptic cortical areas (an approach that we refer to as hodological matching) could enhance neuromodulatory effects on focal epileptic discharges.

Structural connectivity changes in focal epilepsy: Beyond the epileptogenic zone.

Objective: Epilepsy is recognized increasingly as a network disease, with changes extending beyond the epileptogenic zone (EZ). However, more studies of structural connectivity are needed to better understand the behavior and nature of this condition.

Methods: In this study, we applied differential tractography, a novel technique that measures changes in anisotropic diffusion, to assess widespread structural connectivity alterations in a total of 42 patients diagnosed with medically refractory epilepsy (MRE), including 27 patients with focal epilepsy and 15 patients with multifocal epilepsy that were included to validate our hypothesis.

Safety of Concomitant Cortical and Thalamic Stereoencephalography Explorations in Patients With Drug-Resistant Epilepsies.

Background And Objectives: Intracranial electrophysiology of thalamic nuclei has demonstrated involvement of thalamic areas in the propagation of seizures in focal drug-resistant epilepsy. Recent studies have argued that thalamus stereoencephalography (sEEG) may aid in understanding the epileptogenic zone and treatment options. However, the study of thalamic sEEG-associated hemorrhage incidence has not been investigated in a cohort study design.

Functional profile of perilesional gray matter in focal cortical dysplasia: an fMRI study.

Objectives: We aim to investigate the functional profiles of perilesional gray matter (GM) in epileptic patients with focal cortical dysplasia (FCD) and to correlate these profiles with FCD II subtypes, surgical outcomes, and different antiseizure medications (ASMs) treatment response patterns.

Methods: Nine patients with drug-responsive epilepsy and 30 patients with drug-resistant epilepsy (11 were histologically confirmed FCD type IIa, 19 were FCD type IIb) were included. Individual-specific perilesional GM and contralateral homotopic GM layer masks were generated.

Challenging Cortical Explorations in Difficult-to-Localize Seizures: The Rationale and Usefulness of Perisylvian Paralimbic Explorations With Orthogonal Stereoelectroencephalography Depth Electrodes.

Background And Objective: Stereoelectroencephalography (SEEG) is an invasive monitoring method designed to define and localize the epileptogenic zone (EZ) and explore the putative network responsible for the electroclinical seizures using anatomo-functional-electroclinical correlations. When indicated by semiology in selected patients, exploration of both limbic and paralimbic (PL) regions is indispensable. However, the PL cortex is located in deep and highly vascularized areas in proximity to the anterior Sylvian fissure and middle cerebral artery branches.

Stereoelectroencephalography-guided laser ablation in neocortical epilepsy: Electrophysiological correlations and outcome.

Objective: We aimed to study the correlation between seizure outcomes in patients with drug-resistant epilepsy (DRE) who underwent laser interstitial thermal therapy (LITT) and stereoelectroencephalographic electrophysiologic patterns with respect to the extent of laser ablation.

Methods: We retrospectively analyzed 16 consecutive DRE patients who underwent LITT. A seizure onset zone (SOZ) was obtained from multidisciplinary patient management conferences and again was confirmed independently by two epileptologists based on conventional analysis.

Trans-Interhemispheric Stereoelectroencephalography Depth Electrode Placement for Mesial Frontal Lobe Explorations in Medically Refractory Epilepsy: A Technical Note and Case Series.

Background: Stereoelectroencephalography (SEEG) is an established and safe methodology for extra-operative invasive monitoring in patients with medical refractory epilepsy. SEEG has several advantages such as the ability to record deep cortical structures, mapping the epileptogenic zone in a three-dimensional manner, and analyze bihemispheric regions without the need for bilateral craniotomies. In patients with bilateral hemispheric hypotheses, especially the mesial surface of frontal lobes, bilateral lead placement is compulsory to further define and localize the epileptogenic zone.

Epileptic seizures in patients with anti-IgLON5 disease.

Background: Anti-IgLON5 is a rare neurologic disease that can present with epileptic seizures. However, epileptic seizures have not been characterized and are underreported. We aimed to investigate the clinical characteristics and demographics of epileptic seizures in patients with anti-IgLON5 disease.

Focal thalamocortical circuit abnormalities in sleep related epilepsy caused by focal cortical dysplasia type II.

Purpose To investigate the variations of the thalamocortical circuit between the focal cortical dysplasia (FCD) type II patients with sleep-related epilepsy (SRE) and those without SRE (non-SRE). Methods Patients with epilepsy who had histologically proven FCD type II were enrolled. Those without diffusion tensor image and 3-dimensional (3D) T1 MRI sequences were excluded.

Contributions of Magnetoencephalography to Understanding Mechanisms of Generalized Epilepsies: Blurring the Boundary Between Focal and Generalized Epilepsies?

According to the latest operational 2017 ILAE classification of epileptic seizures, the generalized epileptic seizure is still conceptualized as "originating at some point within and rapidly engaging, bilaterally distributed networks." In contrast, the focal epileptic seizure is defined as "." Hence, one of the main concepts of "generalized" and "focal" epilepsy comes from EEG descriptions before the era of source localization, and a presumed simultaneous bilateral onset and bi-synchrony of epileptiform discharges remains a hallmark for generalized seizures.

Response to antiseizure medications in epileptic patients with malformation of cortical development.

Background: Malformation of cortical development (MCD) is one of the most common causes of pharmacoresistant epilepsy. Improving the knowledge of antiseizure medications (ASMs) treatment response in epileptic patients with MCD is crucial for optimal treatment options, either pharmacological therapy or non-pharmacological intervention.

Aim: To investigate the patterns of medical treatment outcome and the predictors for seizure freedom (SF) with ASM regimens in epilepsy caused by MCD.

Update on the Neuroimaging and Electroencephalographic Biomarkers of Epileptogenesis: A Literature Review.

Epilepsy is one of the most common debilitating neurological disorders that lead to severe socio-cognitive dysfunction. While there are currently more than 30 antiseizure medications available for the treatment and prevention of seizures, none address the prevention of epileptogenesis that leading to the development of epilepsy following a potential brain insult. Hence, there is a growing need for the identification of accurate biomarkers of epileptogenesis that enable the prediction of epilepsy following a known brain insult.

Perilesional white matter integrity in drug-resistant epilepsy related to focal cortical dysplasia.

Purpose: We aimed to investigate the differences of white matter (WM) between the focal cortical dysplasia (FCD) patients with drug-resistant epilepsy and those with drug-responsive epilepsy.

Methods: Thirty epileptic patients with MRI-identified or histologically proven FCD were consecutively enrolled. Fractional anisotropy (FA) and mean diffusivity (MD) of the ipsilateral perilesional WM and contralateral homotopic WM layer masks were computed and corrected by the FA/MD of the corresponding hemispheric WM.

Neurovascular networks in epilepsy: Correlating ictal blood perfusion with intracranial electrophysiology.

Perfusion patterns observed in Subtraction Ictal SPECT Co-registered to MRI (SISCOM) assist in focus localization and surgical planning for patients with medically intractable focal epilepsy. While the localizing value of SISCOM has been widely investigated, its relationship to the underlying electrophysiology has not been extensively studied and is therefore not well understood. In the present study, we set to investigate this relationship in a cohort of 70 consecutive patients who underwent ictal and interictal SPECT studies and subsequent stereo-electroencephalography (SEEG) monitoring for localization of the epileptogenic focus and surgical intervention.

Rare but life-threatening aspiration pneumonia related to initiation of clobazam therapy.

Clobazam (CLB) was approved in October 2011 by the United States FDA as an adjunctive therapy for the treatment of seizures associated with Lennox-Gastaut syndrome (LGS) in patients older than the age of 2. Due to its unique chemical design and selective binding to the alpha-2 GABA-receptor, CLB has a decreased tendency for sedation compared to other benzodiazepines. A recent literature review shows that sedation, hypersalivation (drooling), and behavior changes are the most common side effects of CLB.

The feasibility and value of extraoperative and adjuvant intraoperative stereoelectroencephalography in rolandic and perirolandic epilepsies.

Objective: The objective of this study was to illustrate the feasibility and value of extra- and intraoperative stereoelectroencephalography (SEEG) in patients who underwent resection in rolandic and perirolandic regions.

Methods: The authors retrospectively reviewed all consecutive patients with at least 1 year of postoperative follow-up who underwent extra- and intraoperative SEEG monitoring between January 2015 and January 2017.

Results: Four patients with pharmacoresistant rolandic and perirolandic focal epilepsy were identified, who underwent conventional extraoperative invasive SEEG evaluations followed by adjuvant intraoperative SEEG recordings.

Epilepsy imitator: tongue biting caused by sleep-related facio-mandibular myoclonus.

Purpose: Sleep-related facio-mandibular myoclonus(SRFMM) is a rare and under-recognized stereotyped parasomnia. SRFMM can present with isolated tongue biting, which can be misdiagnosed as epilepsy and sleep bruxism. We aimed to investigate the clinical characteristics and demographics of patients with SRFMM.

Epilepsy and Its Interaction With Sleep and Circadian Rhythm.

Growing evidence shows the bidirectional interactions between sleep, circadian rhythm, and epilepsy. Comprehending how these interact with each other may help to advance our understanding of the pathophysiology of epilepsy and develop new treatment strategies to improve seizure control by reducing the medication side effects and the risks associated with seizures. In this review, we present the overview of different temporal patterns of interictal epileptiform discharges and epileptic seizures over a period of 24 consecutive hours.