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Network neuroscience applied to epilepsy holds promise to map pathological networks, localize seizure generators, and inform targeted interventions to control seizures. However, incomplete sampling of the epileptic brain because of sparse placement of intracranial electrodes may affect model results. In this study, we evaluate the sensitivity of several published network measures to incomplete spatial sampling and propose an algorithm using network subsampling to determine confidence in model results. We retrospectively evaluated intracranial EEG data from 28 patients implanted with grid, strip, and depth electrodes during evaluation for epilepsy surgery. We recalculated global and local network metrics after randomly and systematically removing subsets of intracranial EEG electrode contacts. We found that sensitivity to incomplete sampling varied significantly across network metrics. This sensitivity was largely independent of whether seizure onset zone contacts were targeted or spared from removal. We present an algorithm using random subsampling to compute patient-specific confidence intervals for network localizations. Our findings highlight the difference in robustness between commonly used network metrics and provide tools to assess confidence in intracranial network localization. We present these techniques as an important step toward translating personalized network models of seizures into rigorous, quantitative approaches to invasive therapy.

Objective: To predict one‐year seizure freedom, using a combination of relevant clinical variables, following stereotactic laser amygdalohippocampotomy for mesial temporal lobe epilepsy in a series of 101 patients. Methods: Eight predictors of seizure freedom were selected based on their association with medial temporal lobe epilepsy: (1) MRI evidence of mesial temporal sclerosis (MTS); (2) unitemporal interictal epileptiform discharges; (3) absence of generalized tonic–clonic seizures; (4) history of febrile seizures; (5) onset of epilepsy ≤16 years; (6) absence of an auditory, visual, or vertiginous aura; and (7) unitemporal ictal onset; (8) unitemporal PET hypometabolism. We compared four multivariate models: "MTS," using just evidence of MTS; "FULL," using all eight binary predictors; "AIC" using backwards selection of variables; and "SCORE," using a 0‐to‐8‐point ordinal score awarding one point for each binary predictor. Results: In univariate analysis, significant predictors for seizure freedom were evidence of mesial temporal sclerosis (p = 0.011, Fisher exact) and unitemporal interictal discharges (p = 0.005). For multivariate prediction (using leave one‐out cross‐validation), the ordinal SCORE model had a significantly higher area under the curve (AUC 0.70) than the other three models: MTS (AUC 0.54, p = 0.002, Delong's test), FULL (AUC 0.62, p = 0.003), or AIC (AUC 0.53, p < 0.001). Interpretation: An ordinal score incorporating eight independent binary clinical variables predicted seizure freedom better on novel data than a model using MTS alone, a full multivariate model, or a backwards selected model. The ordinal score model represents a simple clinical heuristic to identify which patients should be offered minimally invasive laser surgery. [ABSTRACT FROM AUTHOR]

The piriform cortex (PC) is part of the olfactory system, principally receiving input from the lateral olfactory tract and projecting to downstream components of the olfactory network, including the amygdala. Based on preclinical studies, PC is vulnerable to injury and can be easily kindled as an onset site for seizures. While the role of PC in human epilepsy has been studied indirectly and the subject of speculation, cases of demonstrated PC seizure onset from direct intracranial recording are rare. We present a pediatric patient with drug-resistant focal reflex epilepsy and right mesial temporal sclerosis with habitual seizures triggered by coconut aroma. The patient underwent stereoelectroencephalography with implantation of olfactory cortices including PC, through which we identified PC seizure onset, mapped high-frequency activity associated with presentation of olfactory stimuli and performance on cognitive tasks, and reproduced habitual seizures via cortical stimulation of PC. Coconut odor did not trigger seizures in our work with the patient. Surgical workup resulted in resection of the patient's right amygdala, PC, and mesial temporal pole, following which she has been seizure free for 20 months without functional decline in cognition or smell. Histological findings from resected tissue showed astrogliosis and subpial gliosis. [ABSTRACT FROM AUTHOR]

Mapping of cortical functions is critical for the best clinical care of patients undergoing epilepsy and tumor surgery, but also to better understand human brain function and connectivity. The purpose of this review is to explore existing and potential means of mapping higher cortical functions, including stimulation mapping, passive mapping, and connectivity analyses. We examine the history of mapping, differences between subdural and stereoelectroencephalographic approaches, and some risks and safety aspects, before examining different types of functional mapping. Much of this review explores the prospects for new mapping approaches to better understand other components of language, memory, spatial skills, executive, and socio-emotional functions. We also touch on brain-machine interfaces, philosophical aspects of aligning tasks to brain circuits, and the study of consciousness. We end by discussing multi-modal testing and virtual reality approaches to mapping higher cortical functions. [ABSTRACT FROM AUTHOR]

Objective: Magnetic resonance imaging (MRI)–guided laser interstitial thermal therapy (MRg‐LITT) is an alternative to open epilepsy surgery. We assess safety and effectiveness of MRg‐LITT for extratemporal lobe epilepsy (ETLE) in patients who are considered less favorable for open resection. Methods: We retrospectively reviewed sequential cases of patients with focal ETLE who underwent MRg‐LITT between 2012 and 2019. Epileptogenic zones were determined from standard clinical and imaging data ± stereoelectroencephalography (SEEG). Standard stereotactic techniques, MRI thermometry, and a commercial laser thermal therapy system were used for ablations. Anatomic MRI was used to calculate ablation volumes. Clinical outcomes were determined longitudinally. Results: Thirty‐five patients with mean epilepsy duration of 21.3 ± 12.2 years underwent MRg‐LITT for focal ETLE at a mean age 36.4 ± 12.7 years. A mean 2.59 ± 1.45 trajectories per patient were used to obtain ablation volumes of 8.8 ± 7.5 cm3. Mean follow‐up was 27.3 ± 19.5 months. Of 32 patients with >12 months of follow‐up, 17 (53%) achieved good outcomes (Engel class I + II) of whom 14 (44%) were Engel class I. Subgroup analysis revealed better outcomes for patients with lesional ETLE than for those who were nonlesional, multifocal, or who had failed prior interventions (P =.02). Of 13 patients showing favorable seizure‐onset patterns (localized low voltage fast activity or rhythmic spiking on SEEG) prior to ablation, 9 (69%) achieved good outcomes, whereas only 3 of 11 (27%) who show other slower onset patterns achieved good outcomes. Minor adverse events included six patients with transient sensorimotor neurologic deficits and four patients with asymptomatic hemorrhages along the fiber tract. Major adverse events included one patient with a brain abscess that required stereotactic drainage and one patient with persistent hypothalamic obesity. Three deaths—two seizure‐associated and one suicide—were unrelated to surgical procedures. Significance: MRI‐guided laser interstitial thermal therapy (or MRg‐LITT) was well‐tolerated and yielded good outcomes in a heterogeneous group of ETLE patients. Lesional epilepsy and favorable seizure‐onset patterns on SEEG predicted higher likelihoods of success. [ABSTRACT FROM AUTHOR]

Patients with drug-resistant epilepsy often require surgery to become seizure-free. While laser ablation and implantable stimulation devices have lowered the morbidity of these procedures, seizure-free rates have not dramatically improved, particularly for patients without focal lesions. This is in part because it is often unclear where to intervene in these cases. To address this clinical need, several research groups have published methods to map epileptic networks but applying them to improve patient care remains a challenge. In this study we advance clinical translation of these methods by: (i) presenting and sharing a robust pipeline to rigorously quantify the boundaries of the resection zone and determining which intracranial EEG electrodes lie within it; (ii) validating a brain network model on a retrospective cohort of 28 patients with drug-resistant epilepsy implanted with intracranial electrodes prior to surgical resection; and (iii) sharing all neuroimaging, annotated electrophysiology, and clinical metadata to facilitate future collaboration. Our network methods accurately forecast whether patients are likely to benefit from surgical intervention based on synchronizability of intracranial EEG (area under the receiver operating characteristic curve of 0.89) and provide novel information that traditional electrographic features do not. We further report that removing synchronizing brain regions is associated with improved clinical outcome, and postulate that sparing desynchronizing regions may further be beneficial. Our findings suggest that data-driven network-based methods can identify patients likely to benefit from resective or ablative therapy, and perhaps prevent invasive interventions in those unlikely to do so. [ABSTRACT FROM AUTHOR]

Niemann-Pick disease refers to a group of autosomal recessive lipid storage disorders associated with a variable degree of neurological manifestations in addition to other organ involvement. Niemann-Pick disease is divided into types A-C. Of interest to neurologists is Niemann-Pick type C because of the association with neurological manifestations that are not confined to childhood. The clinical presentation of Niemann-Pick type C is variable, depending on age at onset. Neurological symptoms vary with age: hypotonia, delay in developmental motor milestones, falls, seizures, learning difficulties, ataxia with cognitive deficits and psychosis. The definitive diagnosis of Niemann-Pick type C requires demonstration of abnormal intracellular cholesterol trafficking using the filipin test. Therapeutic interventions are few but one that is of interest is miglustat, which has been approved for specific treatment of the neurological manifestations. It showed improvement in horizontal saccadic eye movement and a trend towards improvement or stabilisation in swallowing, hearing and walking. Niemann-Pick type C should be considered in patients with early-onset ataxia associated with progressive learning/cognitive difficulties even in the absence of vertical gaze palsy. [ABSTRACT FROM AUTHOR]

Spasticity is common in many neurological disorders, such as stroke and multiple sclerosis. It is part of the upper motor neurone syndrome manifesting as increased tone, clonus, spasms, spastic dystonia and co-contractions. The impact of spasticity varies from it being a subtle neurological sign to severe spasticity causing pain and contractures. Existing spasticity can be worsened by external factors such as constipation, urinary tract infections or pressure ulcers. Its management involves identification and elimination of triggers; neurophysiotherapy; oral medications such as baclofen, tizanidine and dantrolene; focal injection of botulinum toxin, alcohol or phenol, or baclofen delivered intrathecally through a pump; and surgical resection of selected dorsal roots of the spinal cord. This article reviews the current understanding of pathophysiology, clinical features and management of spasticity. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 51-year-old man numbness affecting his left side chin. It says that the man underwent a computed tomography (CT) scan of the chest, abdomen and pelvis which revealed a heterogeneous mass within the right lobe of his liver. It mentions that a hepatocellular carcinoma was confirmed with liver biopsy and he was offered a palliative care.

The conventional intracarotid amobarbital (Wada) test has been used to assess memory function in patients being considered for temporal lobe epilepsy (TLE) surgery. Minimally invasive approaches that target the medial temporal lobe (MTL) and spare neocortex are increasingly used, but a knowledge gap remains in how to assess memory and language risk from these procedures. We retrospectively compared results of two versions of the Wada test, the intracarotid artery (ICA-Wada) and posterior cerebral artery (PCA-Wada) approaches, with respect to predicting subsequent memory and language outcomes, particularly after stereotactic laser amygdalohippocampotomy (SLAH). We included all patients being considered for SLAH who underwent both ICA-Wada and PCA-Wada at a single institution. Memory and confrontation naming assessments were conducted using standardized neuropsychological tests to assess pre- to post-surgical changes in cognitive performance. Of 13 patients who initially failed the ICA-Wada, only one patient subsequently failed the PCA-Wada (p=0.003, two-sided binomial test with p 0 =0.5) demonstrating that these tests assess different brain regions or networks. PCA-Wada had a high negative predictive value for the safety of SLAH, compared to ICA-Wada, as none of the patients who underwent SLAH after passing the PCA-Wada experienced catastrophic memory decline (0 of 9 subjects, p <.004, two-sided binomial test with p 0 =0.5), and all experienced a good cognitive outcome. In contrast, the single patient who received a left anterior temporal lobectomy after failed ICA- and passed PCA-Wada experienced a persistent, near catastrophic memory decline. On confrontation naming, few patients exhibited disturbance during the PCA-Wada. Following surgery, SLAH patients showed no naming decline, while open resection patients, whose surgeries all included ipsilateral temporal lobe neocortex, experienced significant naming difficulties (Fisher's exact test, p <.05). These findings demonstrate that (1) failing the ICA-Wada falsely predicts memory decline following SLAH, (2) PCA-Wada better predicts good memory outcomes of SLAH for MTLE, and (3) the MTL brain structures affected by both PCA-Wada and SLAH are not directly involved in language processing.

Objectives: Corpus callosotomy (CC) is used to reduce seizures, primarily in patients with generalized drug-resistant epilepsy (DRE). The invasive nature of the procedure contributes to underutilization despite its potential superiority to other palliative procedures. The goal of this study was to use a multi-institutional epilepsy surgery database to characterize the use of CC across participating centers., Methods: Data were acquired from the Pediatric Epilepsy Research Consortium (PERC) Surgery Database, a prospective observational study collecting data on children 0-18 years referred for surgical evaluation of DRE across 22 U.S. pediatric epilepsy centers. Patient, epilepsy, and surgical characteristics were collected across multiple CC modalities. Outcomes and complications were recorded and analyzed statistically., Results: Eighty-three patients undergoing 85 CC procedures at 14 participating epilepsy centers met inclusion criteria. Mean age at seizure onset was 2.3 years (0-9.4); mean age for Phase I evaluation and surgical intervention were 9.45 (.1-20) and 10.46 (.2-20.6) years, respectively. Generalized seizure types were the most common (59%). Complete CC was performed in 88%. The majority of CC procedures (57%) were via open craniotomy, followed by laser interstitial thermal therapy (LiTT) (20%) and mini-craniotomy/endoscopic (mc/e) (22%). Mean operative times were significantly longer for LiTT, whereas mean estimated blood loss was greater in open cases. Complications occurred in 11 cases (13%) and differed significantly between surgical techniques (p < .001). There was no statistically significant difference in length of postoperative stay across approaches. Mean follow-up was 12.8 months (range 1-39). Favorable Engel outcomes were experienced by 37 (78.7%) of the patients who underwent craniotomy, 10 (58.8%) with LiTT, and 12 (63.2%) with mc/e; these differences were not statistically significant., Significance: CC is an effective surgical modality for children with DRE. Regardless of surgical modality, complication rates are acceptable and seizure outcomes generally favorable. Newer, less-invasive, surgical approaches may lead to increased adoption of this efficacious therapeutic option for pediatric DRE., (© 2023 International League Against Epilepsy.)

Background and Objectives: Epilepsy education has been transformed over the past 2 decades, leading to a need for structured formative assessment tools. The American Epilepsy Society developed the Epilepsy Fellowship In-Training Examination (EpiFITE) to provide high-quality formative assessment for fellows, to stimulate program improvement, and to guide future learning and teaching. The aim of this study was to explore validity evidence for the EpiFITE in meeting these goals., Methods: Validity evidence was sought from multiple sources. The content of the examination was linked to the American Board of Psychiatry and Neurology blueprint for initial certification in epilepsy, and items were developed by trained experts. Internal structure was studied using internal consistency and item analysis. Surveys of fellows and fellowship directors focused on the examination experience (response process) and how results influenced fellow assessment, future learning, and program improvement (relationship to other variables and consequences)., Results: The EpiFITE was first administered in 2020, with 172 examinees from 67 programs. By 2022 (year 3), the EpiFITE was completed by 195 epilepsy fellows from 77 programs. The overall mean score of the examination was stable from year to year, and the committee predicted the difficulty of individual items with a high degree of accuracy. The examination had high internal consistency (Cronbach α 0.76-0.81). The median item discrimination index ranged from 0.17 in 2020 to 0.21 in 2022. Discrimination indices were lower (mean ≤0.10) for items that were either very easy or very difficult and significantly higher (mean >0.20) for other items. Program directors and epilepsy fellows agreed the examination questions were appropriate and agreed that the EpiFITE helped them identify areas for self-directed learning. Program directors also found the examination helpful in identifying areas of strength and areas for improvement within their programs., Discussion: There are several sources of evidence of the quality and validity of the EpiFITE. By exploring this validity evidence, we have identified several best practices in the development and evaluation of a subspecialty examination, and this experience could be helpful for developers of in-training examinations in other subspecialties., Competing Interests: The authors report no disclosures relevant to the manuscript. Go to Neurology.org/NE for full disclosures., (© 2023 American Academy of Neurology.)

The purpose of this review is to describe the functional anatomy of the precuneal cortex and outline some semiological features of precuneal seizures. The precuneal cortex is a structure that occupies the posterior medial portion of the parietal lobe, and it has broad cortical and subcortical connections. Neuroanatomical tracing, functional imaging, as well as electrical stimulation studies of humans and other primates have elucidated many complex integrative functions of the precuneus including visuo-spatial imagery, sensorimotor functions, and consciousness. Based on the understanding of its functions and connectivity, descriptions of potential seizure semiologies are hypothesized and compared to what is available in the literature. The latter is mostly in the form of case reports or case series. Seizures may involve simple or complex motor or sensory manifestations including abnormal eye movements, visual hallucinations, sensation of motion, or medial temporal-like seizures.