Summary
Purpose: We report a multicenter, double‐blind, randomized trial of bilateral stimulation of the anterior nuclei of the thalamus for localization‐related epilepsy.
Methods: Participants ...were adults with medically refractory partial seizures, including secondarily generalized seizures. Half received stimulation and half no stimulation during a 3‐month blinded phase; then all received unblinded stimulation.
Results: One hundred ten participants were randomized. Baseline monthly median seizure frequency was 19.5. In the last month of the blinded phase the stimulated group had a 29% greater reduction in seizures compared with the control group, as estimated by a generalized estimating equations (GEE) model (p = 0.002). Unadjusted median declines at the end of the blinded phase were 14.5% in the control group and 40.4% in the stimulated group. Complex partial and “most severe” seizures were significantly reduced by stimulation. By 2 years, there was a 56% median percent reduction in seizure frequency; 54% of patients had a seizure reduction of at least 50%, and 14 patients were seizure‐free for at least 6 months. Five deaths occurred and none were from implantation or stimulation. No participant had symptomatic hemorrhage or brain infection. Two participants had acute, transient stimulation‐associated seizures. Cognition and mood showed no group differences, but participants in the stimulated group were more likely to report depression or memory problems as adverse events.
Discussion: Bilateral stimulation of the anterior nuclei of the thalamus reduces seizures. Benefit persisted for 2 years of study. Complication rates were modest. Deep brain stimulation of the anterior thalamus is useful for some people with medically refractory partial and secondarily generalized seizures.
Summary Neonatal seizures are a neurological emergency and prompt treatment is required. Seizure burden in neonates can be very high, status epilepticus a frequent occurrence, and the majority of ...seizures do not have any clinical correlate. Detection of neonatal seizures is only possible with continuous electroencephalogram (EEG) monitoring. EEG interpretation requires special expertise that is not available in most neonatal intensive care units (NICUs). As a result, a simplified method of EEG recording incorporating an easy-to-interpret compressed trend of the EEG output (amplitude integrated EEG) from one of the EEG output from one or two channels has emerged as a popular way to monitor neurological function in the NICU. This is not without limitations; short duration and low amplitude seizures can be missed, artefacts are problematic and may mimic seizure-like activity and only a restricted area of the brain is monitored. Continuous multichannel EEG is the gold standard for detecting seizures and monitoring response to therapy but expert interpretation of the EEG output is generally not available. Some centres have set up remote access for neurophysiologists to the cot-side EEG, but reliable interpretation is wholly dependent on the 24 h availability of experts, an expensive solution. A more practical solution for the NICU without such expertise is an automated seizure detection system. This review outlines the current state of the art regarding cot-side monitoring of neonatal seizures in the NICU.
West syndrome (WS), or infantile spasms, is a rare type of epilepsy that usually appears in the 1st year of life. It is characterized by a specific type of seizure called a spasm, which involves ...sudden, brief jerks of the arms, legs, or trunk. These spasms can occur in clusters and may be accompanied by other seizure types. The cause of WS is not clear, but it is thought to be related to abnormal brain development or damage. In some cases, it may be associated with genetic mutations or other underlying conditions such as Down syndrome or tuberous sclerosis. Early diagnosis and treatment are important, as untreated WS can lead to developmental delays and intellectual disability. In this article, a 2-year and 7-month-old male was diagnosed with WS; his hearing evaluation was carried out to assess the impact of syndrome on audition. Audiological test battery was used which reveals hearing sensitivity within normal limits in both the ears. Speech and language skills development were delayed.
Summary
Objective
Intracranial electroencephalography (EEG), performed presurgically in patients with drug‐resistant and difficult‐to‐localize focal epilepsy, samples only a small fraction of brain ...tissue and thus requires strong hypotheses regarding the possible localization of the epileptogenic zone. EEG/fMRI (functional magnetic resonance imaging), a noninvasive tool resulting in hemodynamic responses, could contribute to the generation of these hypotheses. This study assessed how these responses, despite their interictal origin, predict the seizure‐onset zone (SOZ).
Methods
We retrospectively studied 37 consecutive patients who underwent stereo‐EEG (SEEG) and EEG/fMRI that resulted in significant hemodynamic responses. Hemodynamic response maps were co‐registered to postimplantation anatomic imaging, allowing inspection of these responses in relation to SEEG electrode's location. The area containing the most significant t‐value (primary cluster) explored with an electrode was assessed for concordance with SEEG‐defined SOZ. Discriminant analysis was performed to distinguish the primary clusters having a high probability of localizing the SOZ.
Results
Thirty‐one patients had at least one study with primary cluster explored with an electrode, and 24 (77%) had at least one study with primary cluster concordant with the SOZ. Each patient could have multiple types of interictal discharge and therefore multiple studies. Among 59 studies from the 37 patients, 44 had a primary cluster explored with an electrode and 30 (68%) were concordant with the SOZ. Discriminant analysis showed that the SOZ is predictable with high confidence (>90%) if the primary cluster is highly significant and if the next significant cluster is much less significant or absent.
Significance
The most significant hemodynamic response to interictal discharges delineates the subset of the irritative zone that generates seizures in a high proportion of patients with difficult‐to‐localize focal epilepsy. EEG/fMRI generates responses that are valuable targets for electrode implantation and may reduce the need for implantation in patients in whom the most significant response satisfies the condition of our discriminant analysis.
•Advanced MRI can detect subtle epileptogenic lesions missed by conventional MRI.•Interictal PET, ictal SPECT can delineate epileptogenic regions even if MRI is normal.•Multimodal imaging can ...optimize presurgical detection of epileptic cortex.•Functional MRI can localize motor and speech regions and assist focus localization.•DTI helps in presurgical localization of motor fibers, language lateralization.
Children with epilepsy and normal structural MRI pose a particular challenge in localization of epileptic foci for surgical resection. Many of these patients have subtle structural lesions such as mild cortical dysplasia that can be missed by conventional MRI but may become detectable by optimized and advanced MRI acquisitions and post-processing. Specificity of objective analytic techniques such as voxel-based morphometry remains an issue. Combination of MRI with functional imaging approaches can improve the accuracy of detecting epileptogenic brain regions. Analysis of glucose positron emission tomography (PET) combined with high-resolution MRI can optimize detection of hypometabolic cortex associated with subtle cortical malformations and can also enhance presurgical evaluation in children with epileptic spasms. Additional PET tracers may detect subtle epileptogenic lesions and cortex with enhanced specificity in carefully selected subgroups with various etiologies; e.g., increased tryptophan uptake can identify epileptogenic cortical dysplasia in the interictal state. Subtraction ictal SPECT can be also useful to delineate ictal foci in those with non-localizing PET or after failed surgical resection. Presurgical delineation of language and motor cortex and the corresponding white matter tracts is increasingly reliable by functional MRI and DTI techniques; with careful preparation, these can be useful even in young and sedated children. While evidence-based pediatric guidelines are still lacking, the data accumulated in the last decade strongly indicate that multimodal imaging with combined analysis of MRI, PET, and/or ictal SPECT data can optimize the detection of subtle epileptogenic lesions and facilitate seizure-free outcome while minimizing the postsurgical functional deficit in children with normal conventional MRI.
Summary
The International League Against Epilepsy (ILAE) presents a revised operational classification of seizure types. The purpose of such a revision is to recognize that some seizure types can ...have either a focal or generalized onset, to allow classification when the onset is unobserved, to include some missing seizure types, and to adopt more transparent names. Because current knowledge is insufficient to form a scientifically based classification, the 2017 Classification is operational (practical) and based on the 1981 Classification, extended in 2010. Changes include the following: (1) “partial” becomes “focal”; (2) awareness is used as a classifier of focal seizures; (3) the terms dyscognitive, simple partial, complex partial, psychic, and secondarily generalized are eliminated; (4) new focal seizure types include automatisms, behavior arrest, hyperkinetic, autonomic, cognitive, and emotional; (5) atonic, clonic, epileptic spasms, myoclonic, and tonic seizures can be of either focal or generalized onset; (6) focal to bilateral tonic–clonic seizure replaces secondarily generalized seizure; (7) new generalized seizure types are absence with eyelid myoclonia, myoclonic absence, myoclonic–atonic, myoclonic–tonic–clonic; and (8) seizures of unknown onset may have features that can still be classified. The new classification does not represent a fundamental change, but allows greater flexibility and transparency in naming seizure types.
Summary
Gelastic seizures, usually with onset in early infancy, are the hallmark manifestation of hypothalamic hamartoma. This seizure type is directly generated by hamartoma itself, intrinsically ...epileptogenic because of its anatomofunctional organization. Other types of seizures, focal or generalized, may appear during the evolution, probably resulting from mechanisms of secondary epileptogenesis. Nevertheless, the clinical expression and the severity of the syndrome, ranging from a focal drug‐resistant epilepsy to a catastrophic generalized encephalopathy with severe cognitive and behavioral impairments, depends on the size and the site of attachment of the hamartoma. Early suspicion, timely diagnosis, and appropriate treatment are mandatory to reverse a potential catastrophic evolution of this condition.