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About 30% of people with epilepsy (PWE) are drug-resistant. Those with focal seizures may be suitable for epilepsy surgery. Those not amenable to resective surgery can be considered for vagus nerve stimulation (VNS). However, after operative procedures, around 50% of patients continue to experience seizures. A multi-center retrospective study assessing perampanel effectiveness and tolerability for PWE who have undergone surgical resection and/or VNS implantation was performed. The primary outcome was ≥50% reduction in seizure frequency while secondary outcomes included side effects (SEs), dose-related effectiveness, and toxicity. The median perampanel dose was 6 mg. Only one PWE became seizure free. A ≥50% decrease in seizure frequency was observed in 52.8% of the post-resection group and 16.9% of the VNS group ( p

Clinical Features Which Predict Neuronal Surface Autoantibodies in New-Onset Focal Epilepsy: Implications for Immunotherapies McGinty RN, Handel A, Moloney T, et al. J Neurol Neurosurg Psychiatry. 2020;92(3):291-294. doi:10.1136/jnnp-2020-325011Objective:To generate a score which clinically identifies surface-directed autoantibodies in adults with new-onset focal epilepsy and evaluate the value of immunotherapy in this clinical setting.Methods:Prospective clinical and autoantibody evaluations in a cohort of 219 consecutive patients with new-onset focal epilepsy.Results:A total of 10.5% (23/219) of people with new-onset focal epilepsy had detectable serum autoantibodies to known or novel cell surface antigenic targets. Nine of 23 with autoantibodies were diagnosed with encephalitis, by contrast to 0/196 without autoantibodies (P < .0001). Multivariate analysis identified 6 features which predicted autoantibody positivity (area under the curve = 0.83): age ≥54 years, ictal piloerection, lowered self-reported mood, reduced attention, magnetic resonance imaging limbic system changes, and the absence of conventional epilepsy risk factors. Eleven (79%) of 14 patients with detectable autoantibodies, but without encephalitis, showed excellent long-term outcomes (modified Rankin Score = 0) despite no immunotherapy. These outcomes were superior to those of immunotherapy-treated patients with confirmed autoantibody-mediated encephalitis (P < .05).Conclusions:Seizure semiology, cognitive and mood phenotypes, alongside inflammatory investigation findings, aid the identification of surface autoantibodies among unselected people with new-onset focal epilepsy. The excellent immunotherapy-independent outcomes of autoantibody-positive patients without encephalitis suggest immunotherapy administration should be guided by clinical features of encephalitis, rather than autoantibody positivity. Our findings suggest that, in this cohort, immunotherapy-responsive seizure syndromes with autoantibodies largely fall under the umbrella of autoimmune encephalitis. Antibodies Contributing to Focal Epilepsy Signs and Symptoms Score. de Bruijn M, Bastiaansen AEM, Mojzisova H, et al. Ann Neurol. 2021;89(4):698-710. doi:https://doi.org/10.1002/ana.26013.Objective:Diagnosing autoimmune encephalitis (AIE) is difficult in patients with less fulminant diseases such as epilepsy. However, recognition is important, as patients require immunotherapy. This study aims to identify antibodies in patients with focal epilepsy of unknown etiology and to create a score to preselect patients requiring testing.Methods:In this prospective, multicenter cohort study, adults with focal epilepsy of unknown etiology, without recognized AIE, were included, between December 2014 and December 2017, and followed for 1 year. Serum, and if available cerebrospinal fluid, were analyzed using different laboratory techniques. The ACES score was created using factors favoring an autoimmune etiology of seizures (AES), as determined by multivariate logistic regression. The model was externally validated and evaluated using the Concordance (C) statistic.Results:We included 582 patients, with median epilepsy duration of 8 years (interquartile range = 2-18). Twenty (3.4%) patients had AES, of whom 3 had anti-leucine-rich glioma inactivated 1, 3 had anti-contactin-associated protein-like 2, 1 had anti-N-methyl-d-aspartate receptor, and 13 had antiglutamic acid decarboxylase 65 (enzyme-linked immunosorbent assay concentrations >10 000 IU/mL). Risk factors for AES were temporal magnetic resonance imaging hyperintensities (odds ratio [OR] = 255.3, 95% CI = 19.6-3332.2, P < .0001), autoimmune diseases (OR = 13.31, 95% CI = 3.1-56.6, P = .0005), behavioral changes (OR = 12.3, 95% CI = 3.2-49.9, P = .0003), autonomic symptoms (OR = 13.3, 95% CI = 3.1-56.6, P = .0005), cognitive symptoms (OR = 30.6, 95% CI = 2.4-382.7, P = .009), and speech problems (OR = 9.6, 95% CI = 2.0-46.7, P = .005). The internally validated C-statistic was 0.95 and 0.92 in the validation cohort (n = 128). Assigning each factor 1 point, an antibodies contributing to focal epilepsy signs and symptoms (ACES) score ≥2 had a sensitivity of 100% to detect AES, and a specificity of 84.9%.Interpretation:Specific signs point toward AES in focal epilepsy of unknown etiology. The ACES score (cutoff ≥ 2) is useful to select patients requiring antibody testing.

Objective There is little detailed phenotypic characterization of bilateral hippocampal sclerosis (HS). We therefore conducted a multicenter review of people with pharmacoresistant epilepsy and bilateral HS to better determine their clinical characteristics. Methods Databases from 11 EPIGEN centers were searched. For identified cases, clinicians reviewed the medical notes, imaging, and electroencephalographic (EEG), video-EEG, and neuropsychometric data. Data were irretrievably anonymized, and a single database was populated to capture all phenotypic information. These data were compared with phenotyped cases of unilateral HS from the same centers. Results In total, 96 patients with pharmacoresistant epilepsy and bilateral HS were identified (43 female, 53 male; age range = 8-80 years). Twenty-five percent had experienced febrile convulsions, and 27% of patients had experienced status epilepticus. The mean number of previously tried antiepileptic drugs was 5.32, and the average number of currently prescribed medications was 2.99; 44.8% of patients had cognitive difficulties, and 47.9% had psychiatric comorbidity; 35.4% (34/96) of patients continued with long-term medical therapy alone, another 4 being seizure-free on medication. Sixteen patients proceeded to, or were awaiting, neurostimulation, and 11 underwent surgical resection. One patient was rendered seizure-free postresection, with an improvement in seizures for 3 other cases. By comparison, of 201 patients with unilateral HS, a significantly higher number (44.3%) had febrile convulsions and only 11.4% had experienced status epilepticus. Importantly, 41.8% (84/201) of patients with unilateral HS had focal aware seizures, whereas such seizures were less frequently observed in people with bilateral HS, and were never observed exclusively (P = .002; Fisher's exact test). Significance The current work describes the phenotypic spectrum of people with pharmacoresistant epilepsy and bilateral HS, highlights salient clinical differences from patients with unilateral HS, and provides a large platform from which to develop further studies, both epidemiological and genomic, to better understand etiopathogenesis and optimal treatment regimes in this condition.

Key content Epilepsy is the most common serious neurological problem encountered in pregnancy; however, women with epilepsy are often not referred to high-risk pregnancy services. The 2015 Mothers and Babies: Reducing Risk through Audits and Confidential Enquiries across the UK (MBRRACE-UK) report on maternal mortality highlights that the care of pregnant women with epilepsy requires urgent improvement. The two most recently available guidelines (Scottish Intercollegiate Guidelines Network and Royal College of Obstetricians and Gynaecologists guidelines) require comparative critical appraisal. Collaboration between general practitioners, specialist epilepsy nurses/midwives, obstetricians, obstetric physicians, neurologists and anaesthetists is vital to ensure optimal standardised management. Learning objectives To understand the role of pre-conception counselling: to include advice on seizure control, anti-epileptic drugs (AEDs) and pre-conception folic acid. To understand the risk factors associated with poor outcomes in pregnant women with epilepsy. To understand the risks associated with specific types of AEDs: mono- and polytherapy. To understand the issues regarding the titration of AEDs during pregnancy, postnatal and breastfeeding periods. To understand the importance of a multidisciplinary antenatal, intrapartum and postnatal schedule of care and special considerations. Ethical issues When should we advise women to avoid pregnancy? When, how and by whom should AEDs be modified? Are women with epilepsy aware of the risk of sudden unexpected death in epilepsy in pregnancy?

Introduction Literature on New-Onset Refractory Status Epilepticus (NORSE) is scarce and management is guided mainly by retrospective reports, short case series or expert opinions. We aimed to add to the pool of the available data by retrospectively reviewing seven cases of NORSE cases admitted to our hospital over the last five years between January 2014 and March 2019. Methods Fully anonymised data from medical charts, EEG reports, imaging reports, laboratory test results, types of antiepileptic medications, intravenous anaesthetic therapy, and immune therapies received was collected, along with response to treatment, length of hospital stay and outcome at discharge. Results The mean age was 43.5 ± 23.8 years (range 18–75) and three patients were females. Prodromal symptoms consisted mainly of fever (4/7), headache (4/7) and self terminating seizures (7/7), before presenting with status epilepticus. Initial imaging findings were abnormal in 3/7 and CSF analysis in 3/7. All patients underwent intermittent EEG recordings, mainly for titration or tapering of the anaesthetic agents, with the initial goal of achieving burst suppression and cessation of electrographic seizures. Our index case spent the longest time in therapeutic burst suppression (102 days) and remained on thiopentone for 214 days. The mean duration of NICU stay was 88 ± 85.4 days (range 4–225 days) while the mean duration of hospital stay was 113.8 ± 111.2 days (range 17–292). Conclusions The management of patients with NORSE remains challenging, often requiring multiple intravenous anaesthetic treatments, leading to complicated and prolonged hospital and intensive care unit stays but good outcome remains possible.

Purpose: To explore the retention rates and the efficacy and tolerability of perampanel (PER) by using monthly real life data for a period of 12 months. Methods: Longitudinal outcomes of (PER) usage were assessed using actuarial statistics in an observational nonrandomised multicentre study of 181 people with epilepsy (PWE) refractory to first and second line drugs. Graded seizure outcomes, toxicity and the dose of PER were recorded for each month. Results: PWE were followed for a mean of 15.1 months. The total cumulative probability for retention on PER at 12 months was 61.7% and for ≥50% improvement was 38.2%. Most improvements in seizure control occurred soon after initiation of PER, 17% by one month, 32% by six months and 38% by twelve months, and mostly at low doses 53% on 2 mg and 90% up to 6 mg. Improvements, when they occurred, were sustained. The most common side effects were neuropsychiatric, occurring in 28%. The emergence of side effects did not appear to be dose related. Although people with intellectual disability (ID) were more likely to remain on PER they did not show improved seizure control and also reported more side effects. Patients treated with VNS and PER had a worse outcome. Conclusion: Overall around a third of people showed a useful, response to PER therapy. The response to PER is noted usually early in the treatment and for the majority of the patients for doses up to 8 mg.

Our primary objective was to better discern features that can differentiate people with 'mixed' symptomatology from those who experience epileptic seizures (ES) or functional/psychogenic nonepileptic seizures (PNES) alone, in a population of patients referred for video-telemetry. We wished to see if we could establish the prevalence of PNES in this population of interest as well as compare both objective (e.g. videotelemetry reports and heart rate measurements) and subjective, patient-centered measures (reported symptoms and experiences).Data were sourced from a database of all video-telemetry patients admitted to the John Radcliffe Hospital (Oxford, UK) between 1st Jan 2014 and 31st Jan 2016; video-electroencephalogram (vEEG) reports for the above patients; neurology clinic letters; multidisciplinary Team (MDT) reports; psychology assessments and patient notes for all vEEG patients referred for surgical work up. Mixed cases with a dual ES/PNES diagnosis were carefully evaluated again by the Consultant Neurologist under whose care each respective patient was, through case-by-case evaluation of EEG and telemetry reports. We compared mean heart rate during attacks captured on vEEG, number of physical symptoms reported, episode length, and postictal confusion between the three groups (ES; PNES; ES and PNES (mixed)). We evaluated the groups in terms of demographic and psychological parameters as well as prescription of anti-seizure medication. Pearson correlation significance was examined at 95% level of significance for p-values corrected for multiple comparisons.Overall, mixed cases reported experiencing a significantly lower number of physical symptoms compared to PNES cases (p = 0.018). The heart rate of PNES cases was significantly lower than that of mixed cases during the attacks (p = 0.003). ES patients exhibited the highest heart rate of all three groups and a greater degree of postictal confusion (adjusted p = 0.003 and p 0.001, respectively) compared to those with PNES. There was no statistically significant difference in episode length between mixed and ES cases, while PNES patients had significantly longer episode duration (p = 0.021) compared to the mixed group. We noted that 81.6% of PNES patients were taking at least one anti-seizure medication.Patients with mixed seizures seem to be part of a spectrum between ES and PNES cases. Mixed cases are more similar to the ES group with regard to episode length and number of symptoms reported. In the PNES cohort, we found an over-reporting of ictal symptoms (e.g. palpitations, diaphoresis) disproportionate to recorded heart rate, which is lower in PNES than in epileptic attacks. This seems consistent with PNES cases experiencing a degree of impaired interoceptive processing, as part of a functional disorder spectrum. We noted that there was tendency for overmedication in the PNES group. The need for 'de-prescribing' should be addressed with measures that include better liaison with the community care team. With regard to potential autonomic dysregulation in the mixed cases, it might be interesting to see if vagus nerve stimulation could be accompanied by normalization of cardiovascular physiology parameters for people with both epileptic and psychogenic nonepileptic seizures.

Classical views of the medial temporal lobe (MTL) have established that it plays a crucial role in long‐term memory (LTM). Here we demonstrate, in a sample of patients who have undergone anterior temporal lobectomy for the treatment of pharmacoresistant epilepsy, that the MTL additionally plays a specific, causal role in short‐term memory (STM). Patients (n=22) and age‐matched healthy control participants (n=26) performed a STM task with a sensitive continuous report measure. This paradigm allowed us to examine recall memory for object identity, location and object‐location binding, independently on a trial‐by‐trial basis. Our findings point to a specific involvement of MTL in object‐location binding, but, crucially, not retention of either object identity or location. Therefore the MTL appears to perform a specific computation: binding disparate features that belong to a memory. These results echo findings from previous studies, which have identified a role for the MTL in relational binding for LTM, and support the proposal that MTL regions perform such a function for both STM and LTM, independent of the retention duration. Furthermore, these findings and the methodology employed here may provide a simple, sensitive and clinically valuable means to test memory dysfunuction in MTL disorders.

We performed a retrospective review of progressive multifocal leukoencephalopathy (PML) in 30 patients, all of whom were HIV positive (1.6% of all HIV patients admitted for the study period). PML was the first AIDS illness in 53% of patients. The median CD4 count was 30 cells/μl. Unifocal disease as determined by clinical examination occurred in 60%, by computed tomography in 50% and by magnetic resonance imaging in 27%. Hemiparesis and cerebellar ataxia were the commonest presenting clinical syndromes (60% and 43%). Most imaging revealed low density, non-enhancing lesions without mass effect. Definitive or suggestive pathological diagnosis by light and electron microcopy and in situ hybridization was made in 80% of biopsied patients. No one pathological method was definitive in all cases. Nineteen patients commenced treatment with cytosine arabinoside (ara-C). The median survival of the whole group was 4 weeks (range 1–120; mean 12.6 weeks), with four patients surviving for more than 24 weeks. A CD4 count of more than 50 cells/μl was significantly associated with improved survival (12 weeks versus 4 weeks if CD4 count was less than 50). As a whole treatment with ara-C did not significantly improve survival although there appeared to be individual exceptions.

Summary In 1916, von Economo first described encephalitis lethargica (EL), a CNS disorder presenting with pharyngitis followed by sleep disorder, basal ganglia signs (particularly parkinsonism) and neuropsychiatric sequelae. Since the 1916‐1927 epidemic, only sporadic cases have been described. Pathological studies revealed an encephalitis of the midbrain and basal ganglia, with lymphocyte (predominantly plasma cell) infiltration. The EL epidemic occurred during the same time period as the 1918 influenza pandemic, and the two outbreaks have been linked in the medical literature. However, von Economo and other contemporary scientists thought that the 1918 influenza virus was not the cause of EL. Recent examination of archived EL brain material has failed to demonstrate influenza RNA, adding to the evidence that EL was not an invasive influenza encephalitis. By contrast, the findings of intrathecal oligoclonal bands (OCB) and beneficial effects of steroid treatments have provoked the hypothesis that EL may be immune-mediated. We have recently seen 20 patients with a similar EL phenotype, 55% of whom had a preceding pharyngitis. The patients had remarkable similarity to the historical descriptions of EL: sleep disorder (somnolence, sleep inversion or insomnia), lethargy, parkinsonism, dyskinesias and neuropsychiatric symptoms. CSF examination commonly showed elevated protein and OCB (75 and 69% respectively). Investigation found no evidence of viral encephalitis or other recognized causes of rapid-onset parkinsonism. MRI of the brain was normal in 60% but showed inflammatory changes localized to the deep grey matter in 40% of patients. We investigated the possibility that this phenotype could be a postinfectious autoimmune CNS disorder, and therefore similar to Sydenham’s chorea. Anti-streptolysin-O titres were elevated in 65% of patients. Furthermore, western immunoblotting showed that 95% of EL patients had autoantibodies reactive against human basal ganglia antigens. These antibodies were also present in the CSF in four patients tested. By contrast, antibodies reactive against the basal ganglia were found in only 2‐4% of child and adult controls (n = 173, P < 0.0001). Rather than showing polyspecific binding, these antibodies bound to common neural autoantigens of molecular weight 40, 45, 60 and 98 kDa. Regional tissue comparisons showed that the majority of these autoantigens were specific to or enriched in CNS tissue. Immunohistochemistry with secondary staining localized antibody binding to neurons rather than glial populations. Further investigation is required to determine whether these antibodies affect neuronal function (i.e. whether they are pathogenic anti-neuronal antibodies). Histopathology in one case demonstrated striatal encephalitis with perivenous Band T-lymphocytic infiltration. We believe an EL-like syndrome is still prevalent, and propose that this syndrome may be secondary to autoimmunity against deep grey matter neurons.

We present a 19-year-old woman with severe encephalitis and raised intracranial pressure requiring decompressive craniectomy. Her clinical features were consistent with encephalitis in the context of acute primary Epstein-Barr virus (EBV) infection (infectious mononucleosis). Serology, bone marrow aspirate and PCR of blood and cerebrospinal fluid confirmed the diagnosis. She was treated with corticosteroids and aciclovir. She was critically unwell for 3 weeks, requiring artificial ventilation but eventually made a good recovery. EBV encephalitis is uncommon, making the diagnosis and decisions about clinical management challenging.

Understanding functional plasticity in memory networks associated with temporal lobe epilepsy (TLE) is central to predicting memory decline following surgery. However, the extent of functional reorganization within memory networks remains unclear. In this preliminary study, we used novel analysis methods assessing network‐level changes across the brain during memory task performance in patients with TLE to test the hypothesis that hippocampal functions may not readily shift between hemispheres, but instead may show altered intra‐hemispheric organization with unilateral damage. In addition, we wished to relate functional differences to structural changes along specific fibre pathways associated with memory function. Nine pre‐operative patients with intractable left TLE and 10 healthy controls underwent functional MRI during complex scene encoding. Diffusion tensor imaging was additionally performed in the same patients. In our study, we found no evidence of inter‐hemispheric shifts in memory‐related activity in TLE using standard general linear model analysis. However, tensor independent component analysis revealed significant reductions in functional connectivity between bilateral MTL, occipital and left orbitofrontal regions among others in left TLE. This altered orbitofrontal activity was directly related to measures of fornix tract coherence in patients (P < 0.05). Our results suggest that specific fibre pathways, potentially affected by MTL neurodegeneration, may play a central role in functional plasticity in TLE and highlight the importance of network‐based analysis approaches. Relative to standard model‐based methods, novel objective functional connectivity analyses may offer improved sensitivity to subtle changes in the distribution of memory functions relevant for surgical planning in TLE. Hum Brain Mapp, 2009. © 2009 Wiley‐Liss, Inc.

We report a case of thyrotoxicosis associated with chorea and detectable anti-phospholipid antibodies in which a structural abnormality could not be detected on routine imaging but cerebral perfusion single photon emission computed tomography scans suggested a reversible alteration of basal ganglia perfusion. The pathophysiological mechanisms of phospholipid antibody causing chorea in thyrotoxicosis are discussed.

Short-term (STM) and long-term memory (LTM) have largely been considered as separate brain systems reflecting fronto-parietal and medial temporal lobe (MTL) functions, respectively. This functional dichotomy has been called into question by evidence of deficits on aspects of working memory in patients with MTL damage, suggesting a potentially direct hippocampal contribution to STM. As the hippocampus has direct anatomical connections with the thalamus, we tested the hypothesis that damage to thalamic nuclei regulating cortico-cortical interactions may contribute to STM deficits in patients with hippocampal dysfunction. We used diffusion-weighted magnetic resonance imaging-based tractography to identify anatomical subdivisions in patients with MTL epilepsy. From these, we measured resting-state functional connectivity with detailed cortical divisions of the frontal, temporal, and parietal lobes. Whereas thalamo-temporal functional connectivity reflected LTM performance, thalamo-prefrontal functional connectivity specifically predicted STM performance. Notably, patients with hippocampal volume loss showed thalamic volume loss, most prominent in the pulvinar region, not detected in patients with normal hippocampal volumes. Aberrant thalamo-cortical connectivity in the epileptic hemisphere was mirrored in a loss of behavioral association with STM performance specifically in patients with hippocampal atrophy. These findings identify thalamo-cortical disruption as a potential mechanism contributing to STM deficits in the context of MTL damage.

An 18-year-old woman had a partial seizure affecting the left arm with secondary generalization. There was no history of seizures. Her mother recalled that the patient sustained a head injury as a 3-week-old neonate, falling from the sofa onto …

Introduction Autoantibodies against the extracellular domains of the voltage-gated potassium channel (VGKC) complex proteins, leucine-rich glioma-inactivated 1 (LGI1) and contactin-associated protein-2 (CASPR2), are found in patients with limbic encephalitis, faciobrachial dystonic seizures, Morvan’s syndrome and neuromyotonia. However, in routine testing, VGKC-complex-antibodies without LGI1- or CASPR2-reactivities (‘double-negative’) are commoner than LGI1- or CASPR2-specificities. Therefore, the target (s) and clinical associations of double-negative antibodies need to be determined. Methods Sera (n=1131) from several clinically-defined cohorts were tested for IgG-radioimmunoprecipitation of 125I-aDTX-labelled VGKC-complexes, 125I-aDTX and 125I-aDTX-labelled Kv1-subunits, live hippocampal neuron reactivity, and by cell-based assays using Kv1-subunits, LGI1 and CASPR2. Results VGKC-complex-antibodies were found in 162 of 1131 (14%) sera. Ninety of these (56%) had antibodies targeting the extracellular domains of LGI1 or CASPR2. Of the remaining 72 double-negative sera, ten (14%) immunoprecipitated 125I-aDTX itself, and 27 (38%) bound to solubilized co-expressed Kv1.1/1.2/1.6 subunits and/or Kv1.2 subunits alone, at levels proportionate to VGKC-complex-antibody levels (r=0.57, p=0.0017). The Kv1-precipitating samples only bound to permeabilised Kv1-expressing HEK cells. These intracellular Kv1-antibodies mainly associated with non-immune disease aetiologies, poor longitudinal clinical-serological correlations, and a limited immunotherapy-response. Conclusions Double-negative VGKC-complex-antibodies are often directed against cytosolic epitopes of Kv1-subunits, and occasionally against non-mammalian aDTX. These are not neuronal-surface antibodies. They consequently lack pathogenic potential, and do not in themselves support use of immunotherapies. VGKC-complex radioimmunoassay testing should cease; antibodies against LGI1 and CASPR2 provide greater specificity and sensitivity.

Medical students are increasingly turning to the website YouTube as a learning resource. This study set out to determine whether the videos on YouTube accurately depict the type of seizures that a medical student may search for. Two consultant epileptologists independently assessed the top YouTube videos returned following searches for eight terms relating to different categories of seizures. The videos were rated for their technical quality, concordance of diagnosis with an epileptologist-assigned diagnosis, and efficacy as a learning tool for medical education. Of the 200 videos assessed, 106 (63%) met the inclusion criteria for further analysis. Technical quality was generally good and only interfered with the diagnostic process in 8.5% of the videos. Of the included videos, 40.6–46.2% were judged to depict the purported diagnosis with moderate agreement between raters (75% agreement, κ = 0.50). Of the videos returned after searching “tonic–clonic seizure”, 28.6–35.7% were judged to show nonepileptic seizures with almost perfect interrater agreement (92.9% agreement, κ = 0.84). Of the videos returned following the search “pseudoseizure”, 77.8–88.9% of videos were judged to show nonepileptic seizures with substantial agreement (88.9% agreement, κ = 0.61). Across all search terms, 19.8–33% of videos were judged as potentially useful as a learning resource, with fair agreement between raters (75.5% agreement, κ = 0.38). These findings suggest that the majority of videos on YouTube claiming to show specific seizure subtypes are inaccurate, and YouTube should not be recommended as a learning tool for students. However, a small group of videos provides excellent demonstrations of tonic–clonic and nonepileptic seizures, which could be used by an expert teacher to demonstrate the difference between epileptic and nonepileptic seizures.

In the healthy human brain, evidence for dissociable memory networks along the anterior–posterior axis of the hippocampus suggests that this structure may not function as a unitary entity. Failure to consider these functional divisions may explain diverging results among studies of memory adaptation in disease. Using task-based and resting functional MRI, we show that chronic seizures disrupting the anterior medial temporal lobe (MTL) preserve anterior and posterior hippocampal-cortical dissociations, but alter signaling between these and other key brain regions. During performance of a memory encoding task, we found reduced neural activity in human patients with unilateral temporal lobe epilepsy relative to age-matched healthy controls, but no upregulation of fMRI signal in unaffected hippocampal subregions. Instead, patients showed aberrant resting fMRI connectivity within anterior and posterior hippocampal-cortical networks, which was associated with memory decline, distinguishing memory-intact from memory-impaired patients. Our results highlight a critical role for intact hippocampo-cortical functional communication in memory and provide evidence that chronic injury-induced functional reorganization in the diseased MTL is behavioral inefficient.

Occipital lobe epilepsies (OLEs) manifest with occipital seizures from an epileptic focus within the occipital lobes. Ictal clinical symptoms are mainly visual and oculomotor. Elementary visual hallucinations are common and characteristic. Postictal headache occurs in more than half of patients (epilepsy-migraine sequence). Electroencephalography (EEG) is of significant diagnostic value, but certain limitations should be recognized. Occipital spikes and/or occipital paroxysms either spontaneous or photically induced are the main interictal EEG abnormalities in idiopathic OLE. However, occipital epileptiform abnormalities may also occur without clinical relationship to seizures particularly in children. In cryptogenic/symptomatic OLE, unilateral posterior EEG slowing is more common than occipital spikes. In neurosurgical series of symptomatic OLE, interictal EEG abnormalities are rarely strictly occipital. The most common localization is in the posterior temporal regions and less than one-fifth show occipital spikes. In photosensitive OLE, intermittent photic stimulation elicits (1) spikes/polyspikes confined in the occipital regions or (2) generalized spikes/polyspikes with posterior emphasis. In ictal EEG, a well-localized unifocal rhythmic ictal discharge during occipital seizures is infrequent. A bioccipital field spread to the temporal regions is common. Frequency, severity, and response to treatment vary considerably from good to intractable and progressive mainly depending on underlying causes.

A 49-year-old white man returned urgently to the UK after spending 3 months in Goa. He had a several week history of vomiting, weight loss, a widespread desquamating skin rash, and symptoms and signs of a progressive painful sensorimotor neuropathy. He had a mild normocytic anaemia and lymphopenia. Nerve conduction studies revealed a severe predominantly axonal large fibre sensorimotor neuropathy, confirmed on subsequent sural nerve biopsy. Once he had left Goa most of his symptoms started to rapidly settle although the neuropathic symptoms remained severe. Arsenic poisoning was suspected. A spot urine arsenic concentration was 300 microg/l, confirming the diagnosis. He was treated with chelation therapy. Deliberate arsenic poisoning was highly likely.

Right hemisphere activation during functional imaging studies of language has frequently been reported following left hemisphere injury. Few studies have anatomically characterized the specific right hemisphere structures engaged. We used functional MRI (fMRI) with verbal fluency tasks in 12 right-handed patients with left temporal lobe epilepsy (LTLE) and 12 right-handed healthy controls to localize language-related activity in the right inferior frontal gyrus (RIFG). During the phonemic task, LTLE patients activated a significantly more posterior region of the right anterior insula/frontal operculum than healthy controls (P = 0.02). Activation of the left inferior frontal gyrus (LIFG) did not differ significantly between the two groups. This suggests that, following left hemisphere injury, language-related processing in the right hemisphere differs from that with a functionally normal left hemisphere. The localization of activation in the left and right inferior frontal gyri was determined with respect to the anatomical sub-regions pars opercularis (Pop), pars triangularis (Ptr) and pars orbitalis (Por). In the LIFG, both healthy controls (8 out of 12) and LTLE patients (9 out of 12) engaged primarily Pop during phonemic fluency. Activations in the RIFG, however, were located mostly in the anterior insula/frontal operculum in both healthy controls (8 out of 12) and LTLE patients (8 out of 12), albeit in distinct regions. Mapping the locations of peak voxels in relation to previously obtained cytoarchitectonic maps of Broca's area confirmed lack of homology between activation regions in the left and right IFG. Verbal fluency-related activation in the RIFG was not anatomically homologous to LIFG activation in either patients or controls. To test more directly whether RIFG activation shifts in a potentially adaptive manner after left hemisphere injury, fMRI studies were performed in a patient prior to and following anatomical left hemispherectomy for the treatment of Rasmussen's encephalitis. An increase in activation magnitude and posterior shift in location were found in the RIFG after hemispherectomy for both phonemic and semantic tasks. Together, these results suggest that left temporal lobe injury is associated with potentially adaptive changes in right inferior frontal lobe functions in processing related to expressive language.

OBJECTIVE: We sought to determine the incidence of seizures among patients treated with endovascular coil embolization for ruptured intracranial aneurysms because data on which to base antiepileptic drug (AED) prescriptions and advice to patients regarding driving motor vehicles and other high-risk activities are currently lacking. METHODS: We conducted a single-institute, single-operator observational study of 243 patients referred for endovascular treatment after aneurysmal subarachnoid hemorrhage. Prospective data collection was performed, and all successfully treated patients were followed. The incidence of seizures was compared with published surgical data, and logistic regression analysis of potential clinical associations was performed. Patients were followed for up to 7.7 years (mean follow-up period, 21.9 mo). RESULTS : Ictal seizures occurred at the time of subarachnoid hemorrhage in 26 (11%) of 243 patients and correlated with middle cerebral artery aneurysm location, loss of consciousness at ictus, and AED prescription. No patients experienced periprocedural seizures during their hospitalization. Seven of 233 successfully treated patients (3%) experienced seizures more than 30 days alter treatment: late seizures occurred de novo in four patients (1.7%) and in three patients (1.4%) were caused by preesisting epilipsy. Two patients (0.85%) who had de novo seizures developed epilepsy. Late seizures correlated with a history of previous seizures, the presence of a cerebrospinal fluid shunt, and the use of AEDs. CONCLUSION: The low incidence of seizures does not justify the use of prophylctic AED therapy after aneurysmal subarachnoid hemorrhage in patients treated solely with coil embolization, nor does it justify subsequent restrictions on the driving of motor vehicles if the patient is otherwise fit to drive.

Functional magnetic resonance imaging (fMRI), which allows non‐invasive mapping of human cognitive functions, has become an important tool for understanding language function. An understanding of component processes and sources of noise in the images is contributing to increased confidence in the reproductability of studies. This allows clinical applications, e.g., for pre‐surgical lateralisation of language functions in patients with temporal lobe epilepsy. fMRI is a sensitive method for mapping regions involved in language functions. We recently have applied it to study the effect of word surface form on reading with a comparison of responses to Chinese characters or alphabetical Pinyin. Interpretation of fMRI activations must be made with caution; fMRI suggests task‐associated activation, but does not independently confirm that such activity is necessary. However, complementary studies can be performed using transcranial magnetic stimulation (TMS), which can be used to interfere with brain activity in a specific region transiently for characterisation of the behavioural effects. We describe how TMS combined with fMRI has confirmed a role for the left inferior frontal cortex in semantic processing. Hum. Brain Mapping 18:239–247, 2003. © 2003 Wiley‐Liss, Inc.

Defining language lateralization is important to minimize morbidity in patients treated surgically for temporal lobe epilepsy (TLE). Functional magnetic resonance imaging (fMRI) offers a promising, noninvasive, alternative strategy to the Wada test. Here we have used fMRI to study healthy controls and patients with TLE in order to (i) define language-related activation patterns and their reproducibility; (ii) compare lateralization determined by fMRI with those from of the Wada test; and (iii) contrast different methods of assessing fMRI lateralization. Twelve healthy right-handed controls and 19 right-handed preoperative patients with TLE (12 left- and seven right-TLE) were studied at 3T using fMRI and a verbal fluency paradigm. A Wada test also was performed on each of the patients. Greater activation was found in several areas in the right hemisphere for the left-TLE group relative to controls or right-TLE patients. Relative hemispheric activations calculated based on either the extent or the mean signal change gave consistent results showing a more bihemispheric language representation in the left-TLE patients. There was good agreement between the Wada and fMRI results, although the latter were more sensitive to involvement of the nondominant right hemisphere. The reproducibility of the fMRI values was lowest for the more bihemispherically represented left-TLE patients. Overall, our results further demonstrate that noninvasive fMRI measures of language-related lateralization may provide a practical and reliable alternative to invasive testing for presurgical language lateralization in patients with TLE. The high proportion (33%) of left-TLE patients showing bilateral or right hemispheric language-related lateralization suggests that there is considerable plasticity of language representation in the brains of patients with intractable TLE.

Demonstration that contrast in magnetic resonance images can be generated based on differences in blood oxygenation has led to an explosion of interest in so-called functional magnetic resonance imaging (FMRI). FMRI can be used to map increases in blood flow that accompany local synaptic activity in the brain. The technique has proved remarkably sensitive and has been used to map a broad range of cognitive, motor and sensory processes in the brain entirely non-invasively. More recently, efforts have been made to extend this technique to the analysis of clinical problems. A major application is for presurgical localization of cerebral functions, e.g. in the surgical treatment of epilepsy. The technique also is beginning to provide information on functional consequences of abnormal brain development. Perhaps most exciting are applications to neurological impairments that are not associated with structural abnormalities, such as learning problems, dyslexia and movement disorders. It is possible that useful applications of FMRI may be found for directly mapping sites of action of CNS-active drugs. Although the extent of the potential clinical applications of this new brain mapping technique is not clear, the widespread availability of MRI scanners suggests that the technique should in some form soon become a routine tool in major neuroradiological centres.