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Objective: Focal cortical dysplasia (FCD) is the most common etiology of surgically‐remediable epilepsy in children. Eighty‐seven percent of patients with FCD develop epilepsy (75% is pharmacoresistant epilepsy [PRE]). Focal to bilateral tonic–clonic (FTBTC) seizures are associated with worse surgical outcomes. We hypothesized that children with FCD‐related epilepsy with FTBTC seizures are more likely to develop PRE due to lesion interaction with restricted cortical neural networks. Methods: Patients were selected retrospectively from radiology and surgical databases from Children's National Hospital. Inclusion criteria: 3T magnetic resonance imaging (MRI)–confirmed FCD from January 2011 to January 2020; ages 0 days to 22 years at MRI; and 18 months of documented follow‐up. FCD dominant network (Yeo 7‐network parcellation) was determined. Association of FTBTC seizures with epilepsy severity, surgical outcome, and dominant network was tested. Binomial regression was used to evaluate predictors (FTBTC seizures, age at seizure onset, pathology, hemisphere, lobe) of pharmacoresistance and Engel outcome. Regression was used to evaluate predictors (age at seizure onset, pathology, lobe, percentage default mode network [DMN] overlap) of FTBTC seizures. Results: One hundred seventeen patients had a median age at seizure onset of 3.00 years (interquartile range [IQR].42–5.59 years). Eighty‐three patients had PRE (71%); 34 had pharmacosensitive epilepsy (PSE) (29%). Twenty patients (17%) had FTBTC seizures. Seventy‐three patients underwent epilepsy surgery. Multivariate regression showed that FTBTC seizures are associated with an increased risk of PRE (odds ratio [OR] 6.41, 95% confidence interval [CI] 1.21–33.98, p =.02). FCD hemisphere/lobe was not associated with PRE. Percentage DMN overlap predicts FTBTC seizures. Seventy‐two percent (n = 52) overall and 53% (n = 9) of patients with FTBTC seizures achieved Engel class I outcome. Significance: In a heterogeneous population of surgical and non‐operated patients with FCD‐related epilepsy, the presence of FTBTC seizures is associated with a tremendous risk of PRE. This finding is a recognizable marker to help neurologists identify those children with FCD‐related epilepsy at high risk of PRE and can flag patients for earlier consideration of potentially curative surgery. The FCD‐dominant network also contributes to FTBTC seizure clinical expression. [ABSTRACT FROM AUTHOR]

Objective: Reorganization of the language network from typically left‐lateralized frontotemporal regions to bilaterally distributed or right‐lateralized networks occurs in anywhere from 25%–30% of patients with focal epilepsy. In patients who have been recently diagnosed with epilepsy, an important question remains as to whether it is the presence of seizures or the underlying epilepsy etiology that leads to atypical language representations. This question becomes even more interesting in pediatric samples, where the typical developmental processes of the language network may confer more variability and plasticity in the language network. We assessed a carefully selected cohort of children with recent‐onset epilepsy to examine whether it is the effects of seizures or their underlying cause that leads to atypical language lateralization. Methods: We used functional magnetic resonance imaging (fMRI) to compare language laterality in children with recently diagnosed focal unaware epilepsy and age‐matched controls. Age at epilepsy onset (age 4 to 6 years vs age 7 to 12 years) was also examined to determine if age at onset influenced laterality. Results: The majority of recent‐onset patients and controls exhibited left‐lateralized language. There was a significant interaction such that the relationship between epilepsy duration and laterality differed by age at onset. In children with onset after age 6, a longer duration of epilepsy was associated with less left‐lateralized language dominance. In contrast, in children with onset between 4 and 6 years of age, a longer duration of epilepsy was not associated with less left language dominance. Significance: Our results demonstrate that although language remained largely left‐lateralized in children recently diagnosed with epilepsy, the impact of seizure duration depended on age at onset, indicating that the timing of developmental and disease factors are important in determining language dominance. [ABSTRACT FROM AUTHOR]

Advances in functional imaging have provided noninvasive techniques to probe brain organization of multiple constructs including language and memory. Because of high overall rates of agreements with older techniques, including Wada testing and cortical stimulation mapping ( CSM), some have proposed that those approaches should be largely abandoned because of their invasiveness, and replaced with noninvasive functional imaging methods. High overall agreement, however, is based largely on concordant language lateralization in series dominated by cases of typical cerebral dominance. Advocating a universal switch from Wada testing and cortical stimulation mapping to functional magnetic resonance imaging (f MRI) or magnetoencephalography ( MEG) ignores the differences in specific expertise across epilepsy centers, many of which often have greater skill with one approach rather than the other, and that Wada, CSM, f MRI, and MEG protocols vary across institutions resulting in different outcomes and reliability. Specific patient characteristics also affect whether Wada or CSM might influence surgical management, making it difficult to accept broad recommendations against currently useful clinical tools. Although the development of noninvasive techniques has diminished the frequency of more invasive approaches, advocating their use to replace Wada testing and CSM across all epilepsy surgery programs without consideration of the different skills, protocols, and expertise at any given center site is ill-advised. A PowerPoint slide summarizing this article is available for download in the Supporting Information section . [ABSTRACT FROM AUTHOR]

The timing and developmental factors underlying the establishment of language dominance are poorly understood. We investigated the degree of lateralization of traditional frontotemporal and modulatory prefrontal-cerebellar regions of the distributed language network in children ( n = 57) ages 4 to 12-a critical period for language consolidation. We examined the relationship between the strength of language lateralization and neuropsychological measures and task performance. The fundamental language network is established by four with ongoing maturation of language functions as evidenced by strengthening of lateralization in the traditional frontotemporal language regions; temporal regions were strongly and consistently lateralized by age seven, while frontal regions had greater variability and were less strongly lateralized through age 10. In contrast, the modulatory prefrontal-cerebellar regions were the least strongly lateralized and degree of lateralization was not associated with age. Stronger core language skills were significantly correlated with greater right lateralization in the cerebellum. Hum Brain Mapp 35:270-284, 2014. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The Common Data Element (CDE) Project was initiated in 2006 by the National Institute of Neurological Disorders and Stroke (NINDS) to develop standards for performing funded neuroscience-related clinical research. CDEs are intended to standardize aspects of data collection; decrease study start-up time; and provide more complete, comprehensive, and equivalent data across studies within a particular disease area. Therefore, CDEs will simplify data sharing and data aggregation across NINDS-funded clinical research, and where appropriate, facilitate the development of evidenced-based guidelines and recommendations. Epilepsy-specific CDEs were established in nine content areas: (1) Antiepileptic Drugs (AEDs) and Other Antiepileptic Therapies (AETs), (2) Comorbidities, (3) Electrophysiology, (4) Imaging, (5) Neurological Exam, (6) Neuropsychology, (7) Quality of Life, (8) Seizures and Syndromes, and (9) Surgery and Pathology. CDEs were developed as a dynamic resource that will accommodate recommendations based on investigator use, new technologies, and research findings documenting emerging critical disease characteristics. The epilepsy-specific CDE initiative can be viewed as part of the larger international movement toward 'harmonization' of clinical disease characterization and outcome assessment designed to promote communication and research efforts in epilepsy. It will also provide valuable guidance for CDE improvement during further development, refinement, and implementation. This article describes the NINDS CDE Initiative, the process used in developing Epilepsy CDEs, and the benefits of CDEs for the clinical investigator and NINDS. [ABSTRACT FROM AUTHOR]

Presents the highlights of the annual meeting of the American Epilepsy Society held in Philadelphia, Pennsylvania. Date of the event; Participant of the meeting; Program and activities of the congress; Theme of the convention.

Imaging plays an increasingly important role in the evaluation of children with complex partial seizures. Most partial epilepsy, especially of temporal lobe origin, begins during childhood. Structural imaging with high-resolution MRI can help identify the etiology of partial seizure disorders in many children. MRI studies also show the more widespread effect of seizures on brain structure. Progressive volume loss of the hippocampal formation in some patients with temporal lobe epilepsy provides evidence that continued seizures may be associated with progressive neuronal injury. FDG-PET studies show regional decreases in glucose consumption in the cortical zone from which seizures arise. Functional abnormalities often are more extensive than the seizure focus. Studies in children with recent-onset epilepsy show that metabolic abnormalities are considerably less common than in adults with partial epilepsy, supporting the notion that in some patients there may be progressive metabolic changes that occur with continued seizures. Functional MRI may be used to identify language areas in children with partial epilepsy. fMRI language tasks reliably identify the dominant hemisphere for language dominance when compared to the intracarotid amytal procedure. Tests of verbal fluency and semantic decision identify frontal lobe language areas, while reading text paradigms and auditory passage paradigms are better for identifying temporal language areas. A panel of paradigms is best used to identify language areas in children being considered for epilepsy surgery. fMRI is a valuable tool for elucidating the impact of chronic neurologic disease states on the functional organization of language networks during development. MRDD Research Reviews 6:220–226, 2000. Published 2000 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]