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Poststroke epilepsy is a major ischaemic/haemorrhagic stroke complication. Seizure recurrence risk estimation and early therapeutic intervention are critical, given the association of poststroke epilepsy with worse functional outcomes, quality of life and greater mortality. Several studies have reported risk factors for seizure recurrence; however, in poststroke epilepsy, the role of EEG in predicting the risk of seizures remains unclear. This multicentre observational study aimed to clarify whether EEG findings constitute a risk factor for seizure recurrence in patients with poststroke epilepsy. Patients with poststroke epilepsy were recruited from the PROgnosis of POst-Stroke Epilepsy study, an observational multicentre cohort study. The enrolled patients with poststroke epilepsy were those admitted at selected hospitals between November 2014 and June 2017. All patients underwent EEG during the interictal period during admission to each hospital and were monitored for seizure recurrence over 1 year. Board-certified neurologists or epileptologists evaluated all EEG findings. We investigated the relationship between EEG findings and seizure recurrence. Among 187 patients with poststroke epilepsy (65 were women with a median age of 75 years) admitted to the lead hospital, 48 (25.7%) had interictal epileptiform discharges on EEG. During the follow-up period (median, 397 days; interquartile range, 337–450 days), interictal epileptiform discharges were positively correlated with seizure recurrence (hazard ratio, 3.82; 95% confidence interval, 2.09–6.97; P < 0.01). The correlation remained significant even after adjusting for age, sex, severity of stroke, type of stroke and generation of antiseizure medications. We detected periodic discharges in 39 patients (20.9%), and spiky/sharp periodic discharges were marginally associated with seizure recurrence (hazard ratio, 1.85; 95% confidence interval, 0.93–3.69; P = 0.08). Analysis of a validation cohort comprising 187 patients with poststroke epilepsy from seven other hospitals corroborated the association between interictal epileptiform discharges and seizure recurrence. We verified that interictal epileptiform discharges are a risk factor for seizure recurrence in patients with poststroke epilepsy. Routine EEG may facilitate the estimation of seizure recurrence risk and the development of therapeutic regimens for poststroke epilepsy.

Motivated by the challenges raised by diagnosing poststroke epilepsy (PSE), especially in nonmotor onset seizure (non-MOS), we aimed to investigate the features of non-MOS, including seizure sequences, patient characteristics, and electrophysiological and imaging findings in PSE.This observational cohort study enrolled patients with PSE whose seizure onset was witnessed. According to the International League Against Epilepsy (ILAE) 2017 seizure classification, we classified seizure-onset symptoms into the non-MOS and MOS groups. We compared the different clinical characteristics between the two groups.Between 2011 and 2018, we enrolled 225 patients with PSE (median age, 75 years), consisting of 97 (43%) with non-MOS and 128 (57%) with MOS. Overall, 65 (67%) of the patients without MOS had no subsequent convulsions. Multivariable logistic regression analysis showed significant associations of non-MOS with absence of poststroke hemiparesis (adjusted odds ratio [OR], 1.88; 95% confidence interval [CI], 1.03-3.42), frontal stroke lobe lesions (OR, 2.11; 95% CI, 1.14-3.91), and putaminal stroke lesions (OR, 2.51; 95% CI, 1.22-5.18) as negative indicators. Postictal single-photon emission computed tomography (SPECT) detected prolonged hyperperfusion in the temporal lobe more frequently in the non-MOS than in the MOS group (48% vs 31%; p = .02). The detection rate was higher than spikes/sharp waves in scalp electroencephalography, both in the non-MOS group (72% vs 33%; p .001) and the MOS group (68% vs 29%; p .001).This study provides the clinical features of non-MOS in patients with PSE. Compared with the patients with MOS, patients with non-MOS showed less likely subsequent convulsive seizures, highlighting the clinical challenges. Postictal perfusion imaging and negative indicators of the non-MOS type may help diagnose and stratify PSE.

BACKGROUND Benign adult familial myoclonus epilepsy (BAFME) is one of the diseases that cause cortical myoclonus (CM) with giant somatosensory evoked potentials (SEPs). There are no useful diagnostic biomarkers differentiating BAFME from other CM diseases. OBJECTIVE To establish reliable biomarkers including high-frequency oscillations (HFOs) with giant SEPs for the diagnosis of BAFME. METHODS This retrospective case study included 49 consecutive CM patients (16 BAFME and 33 other CM patients) who exhibited giant P25 or N35 SEPs. SEPs were processed by a band-pass filter of 400-1000 Hz to analyze HFOs. Clinical and SEP findings were compared between (1) BAFME and other CM groups and (2) patients with presence and absence of P25-HFOs (HFOs superimposed on giant P25). The diagnostic power of each factor for BAFME was calculated. RESULTS All 16 BAFME patients showed SEP P25-HFOs with significantly higher occurrence (P

Background The role of B cells in the pathogenesis of multiple sclerosis (MS) is a subject of much research. We report a case of a MS patient who presented with subacute diffuse lesions in the limbic system and short-term memory loss. Case presentation A male patient had experienced numbness in the left upper extremity at the age of 17 years, but this disappeared without treatment. At 19 years-of-age, he developed subacute short-term memory loss followed by paralysis and sensory disturbance in the left upper and lower extremities. Magnetic resonance brain fluid-attenuated/T2-weighted imaging showed diffuse high-intensity lesions in the medial parts of both temporal lobes, and spotty multiple lesions in the periventricular and subcortical white matter. Twenty days later, a new lesion was observed around the right putamen, and the temporal lesions had disappeared. A symptomatic cervical lesion with gadolinium enhancement was observed at C3. This lesion involved just one vertebral segment. Cerebrospinal fluid analysis showed no pleocytosis or elevated protein levels, but did show oligoclonal immunoglobulin G bands. No antibodies against aquaporin-4 or myelin oligodendrocyte glycoprotein were detected in the serum, and anti-N-methyl-D-aspartate receptor was not detected in the cerebrospinal fluid. We diagnosed the patient with MS despite the atypical diffuse lesions in the limbic system and the short-term memory loss. Corticosteroid medication effectively treated the symptoms in his extremities and his impaired memory. Conclusions The present case shows that cortical lesions can occur in MS patients and might be induced by B cell-mediated mechanisms.

Objective To elucidate the effects of perampanel (PER) on refractory cortical myoclonus for dose, etiology and somatosensory-evoked potential (SEP) findings. Methods We examined 18 epilepsy patients with seizure and cortical myoclonus. Based on data accumulated before and after PER treatment, correlations among clinical scores in myoclonus and activities of daily life (ADL); early cortical components of SEP; and PER blood concentration, were analyzed. Results PER (mean dose: 3.2 ± 2.1 mg/day) significantly improved seizures, myoclonus and ADL and significantly decreased the amplitude of and prolonged latency of giant SEP components. The degree of P25 and N33 prolongations (23.8 ± 1.6 to 24.7 ± 1.7 ms and 32.1 ± 4.0 to 33.7 ± 3.4 ms) were significantly correlated with improved ADL score (p = 0.019 and p = 0.025) and blood PER concentration (p = 0.011 and p = 0.025), respectively. Conclusions Low-dose PER markedly improved myoclonus and ADL in patients with refractory cortical myoclonus. Our results suggest that SEP, particularly P25 latency, can be used as a potential biomarker for assessing the objective effects of PER on intractable cortical myoclonus. Significance In this study, PER lessened the degree of synchronized discharges in the postsynaptic neurons in the primary motor cortex.

Patient 1 was a 40-year-old man, who suffered from right leg myoclonus 1 week after an episode of fever and headache. Myoclonus disappeared 4 months after administration of clonazepam. Patient 2 was a 42-year-old man, who suffered from right leg myoclonus, attacks of speech arrest and a generalized tonic-clonic seizure. His symptoms disappeared after steroid-pulse therapy, but right leg myoclonus and episodic impairment of consciousness recurred within a month. He underwent another steroid-pulse therapy and his symptoms disappeared. In both patients, cerebrospinal fluid (CSF) study showed pleocytosis and elevated protein level, electrophysiological study showed cortical reflex by stimulation of the right tibial nerve, and brain MRI showed the high intensity area in the left parietal lobe. In addition, on electroencephalogram (EEG) spikes at vertex preceded myoclonic jerk of the right tibialis anterior muscle in both patients. These findings indicate that focal cortical reflex myoclonus was accompanied by acute central nervous system (CNS) infection. Furthermore, in both patients, autoantibody against glutamate receptor subunits e2 was detected both in serum and CSF, which also suggest that autoimmune mechanism contributed in the pathophysiology of acute development of focal cortical reflex myoclonus.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a hereditary and progressive small-vessel disease caused by NOTCH3 mutations, pathologically characterized by the degeneration of vascular mural cells, white matter changes, and ischemic strokes. Recently, dysautoregulation has received increasing attention regarding the pathogenesis of stroke in CADASIL. Here, we report a CADASIL case with a novel Cys323Trp mutation in the NOTCH3 gene, which suggests a close relationship between hemodynamic factors and clustering of cerebral infarctions in CADASIL. A 47-year-old male patient presented with internal border-zone infarcts in the bilateral hemispheres and was diagnosed with CADASIL by the presence of granular osmiophilic material and the accumulation of the Notch3 extracellular domain around small vessels. A literature review revealed 7 reports of similar CADASIL cases with clustering of cerebral infarctions related to blood pressure fluctuations. Not only large-artery stenosis but also small-vessel pathologies potentiate watershed infarctions, which might be triggered by hemodynamic fluctuation due to cerebral dysautoregulation.

Spinocerebellar ataxia type 2 (SCA2), an autosomal dominant cerebellar disorder belonging to the polyglutamine (polyQ) diseases, is characterized by progressive ataxia, slow saccadic eye movement, hyporeflexia, peripheral neuropathy, and pyramidal and extrapyramidal signs.1 The cause of SCA2 is a CAG repeat expansion, sometimes interrupted by CAA within, in ATXN2 on chromosome 12q24.2,3 Previous reports have shown that the presence of 33 or more heterozygous trinucleotide repeats is pathogenic, whereas 14 to 31 repeats is normal.3,4 We report a case of late-onset SCA2 with homozygous alleles of 31 trinucleotide repeats in ATXN2 .