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1.
《Clinical neurophysiology》2019,130(12):2231-2237
ObjectiveThe clinical and neurophysiological characteristics of myoclonus in Angelman syndrome (AS) have been evaluated in single case or small cohorts, with contrasting results. We evaluated the features of myoclonus in a wide cohort of AS patients.MethodsWe performed polygraphic EEG-EMG recording in 24 patients with genetically confirmed AS and myoclonus. Neurophysiological investigations included jerk-locked back-averaging (JLBA), cortico-muscular coherence (CMC) and generalised partial directed coherence (GPDC). CMC and GPDC analyses were compared to those obtained from 10 healthy controls (HC).ResultsTwenty-four patients (aged 3–35 years, median 20) were evaluated. Sequences of quasi-continuous rhythmic jerks mostly occurred at alpha frequency or just below (mean 8.4 ± 1.4 Hz), without EEG correlate. JLBA did not show any clear transient preceding the jerks. CMC showed bilateral over-threshold CMC in alpha band that was prominent on the contralateral hemisphere in the patient group as compared to HC group. GPDC showed a significantly higher alpha outflow from both hemispheres toward activated muscles in the patient group, and a significantly higher beta outflow from contralateral hemisphere in the HC group.ConclusionsThese neurophysiological findings suggest a subcortical generator of myoclonus in AS.SignificanceMyoclonus in AS has not a cortical origin as previously hypothesised. 相似文献
2.
《Ultrasound in medicine & biology》2015,41(12):3172-3181
Fetal activity parameters such as movements, heart rate and the related parameters are essential indicators of fetal wellbeing, and no device provides simultaneous access to and sufficient estimation of all of these parameters to evaluate fetal health. This work was aimed at collecting these parameters to automatically separate healthy from compromised fetuses. To achieve this goal, we first developed a multi-sensor–multi-gate Doppler system. Then we recorded multidimensional Doppler signals and estimated the fetal activity parameters via dedicated signal processing techniques. Finally, we combined these parameters into four sets of parameters (or four hyper-parameters) to determine the set of parameters that is able to separate healthy from other fetuses. To validate our system, a data set consisting of two groups of fetal signals (normal and compromised) was established and provided by physicians. From the estimated parameters, an instantaneous Manning-like score, referred to as the ultrasonic score, was calculated and was used together with movements, heart rate and the associated parameters in a classification process employing the support vector machine method. We investigated the influence of the sets of parameters and evaluated the performance of the support vector machine using the computation of sensibility, specificity, percentage of support vectors and total classification error. The sensitivity of the four sets ranged from 79% to 100%. Specificity was 100% for all sets. The total classification error ranged from 0% to 20%. The percentage of support vectors ranged from 33% to 49%. Overall, the best results were obtained with the set of parameters consisting of fetal movement, short-term variability, long-term variability, deceleration and ultrasound score. The sensitivity, specificity, percentage of support vectors and total classification error of this set were respectively 100%, 100%, 35% and 0%. This indicated our ability to separate the data into two sets (normal fetuses and pathologic fetuses), and the results highlight the excellent match with the clinical classification performed by the physicians. This work indicates the feasibility of detecting compromised fetuses and also represents an interesting method of close fetal monitoring during the entire pregnancy. 相似文献
3.
《Clinical neurophysiology》2020,131(1):213-224
ObjectiveSystematically review the abnormalities in event related potential (ERP) recorded in Rett Syndrome (RTT) patients and animals in search of translational biomarkers of deficits related to the particular neurophysiological processes of known genetic origin (MECP2 mutations).MethodsPubmed, ISI Web of Knowledge and BIORXIV were searched for the relevant articles according to PRISMA standards.ResultsERP components are generally delayed across all sensory modalities both in RTT patients and its animal model, while findings on ERPs amplitude strongly depend on stimulus properties and presentation rate. Studies on RTT animal models uncovered the abnormalities in the excitatory and inhibitory transmission as critical mechanisms underlying the ERPs changes, but showed that even similar ERP alterations in auditory and visual domains have a diverse neural basis. A range of novel approaches has been developed in animal studies bringing along the meaningful neurophysiological interpretation of ERP measures in RTT patients.ConclusionsWhile there is a clear evidence for sensory ERPs abnormalities in RTT, to further advance the field there is a need in a large-scale ERP studies with the functionally-relevant experimental paradigms.SignificanceThe review provides insights into domain-specific neural basis of the ERP abnormalities and promotes clinical application of the ERP measures as the non-invasive functional biomarkers of RTT pathophysiology. 相似文献
4.
报道52倒6个类型植物神经癫痫,重点分析了脑电图的变化,脑电图异常率100%,69.4%的病例出现两侧阵发性4~7Hzθ节律及6和14Hz阳性棘波,提示中线深部有功能紊乱,亦支持丘脑及脑干部有病变。此外蝶骨电极能提高脑电图对本病的阳性诊断率,值得采用。本文证明脑电图对植物神经性癫痫与非癫痫的鉴别诊断,具有肯定的价值。 相似文献
5.
目的:观察24小时动态脑电图与视频脑电图对癫发作类型鉴别的价值。方法:242例患者进行24小时视频脑电监测,陪同家属做记录。结果由两名医师判定,一人关闭视频进行分析作为动态脑电组。一人打开视频分析作为视频脑电组。结果:242例患者中63例临床发作伴癫样放电,视频脑电监测后符合例数53例(84%),动态脑电监测后符合例数39例(61·9%),有显著性差异。结论:视频脑电监测与动态脑电图对癫发作类型的鉴别有显著的差异,视频脑电图更准确。 相似文献
6.
EEGs of 42 patients with herpes zoster and 6 with herpes zoster-associated encephalitis were studied to characterize the nature and prevalence of EEG abnormalities in apparently uncomplicated herpes zoster. Thirty-one percent of herpes zoster patients had EEG changes with reduced rhythm frequency ranging from 7 to 2 Hz activity. Frontotemporal localization was observed in 54% of the abnormal EEGs. When compared to EEG in herpes zoster associated encephalitis, the findings were qualitatively the same, but tended to be more severe in the encephalitis cases. No effect of acyclovir on the EEG could be demonstrated. 相似文献
7.
Uta Lichter-Konecki Christian Benninger Werner E. Brandeis Peter Matthis Dieter Scheffner 《Pediatric hematology and oncology》1987,4(1):77-85
Thirteen children with acute lymphoblastic leukemia (ALL) were investigated before and during cytotoxic therapy. EEG findings were correlated with the clinical course and the therapy protocol and compared with normal data obtained from 295 healthy children. Frequency analysis of the background activity of the EEG revealed an initial slowing of the background activity prior to therapy and further slowing each time a combination of vincristine (VCR), daunorubicine (DAU) or adriblastine (ADR), prednisone (FRED), and L-asparaginase (L-ASP) was administered. The slowing of the background activity correlated only with the administration of these drugs. DAU, ADR, and FRED are not known to influence the EEG; therefore, VCR and L-ASP remain the primary candidates responsible for the central nervous system alteration. 相似文献
8.
9.
王翠欣 《现代电生理学杂志》2006,13(1):17-19
目的:探讨头痛、头痛型癫与脑电图(EEG)的相关性。方法:对22例发作性头痛的患儿,在头痛间期进行了常规EEG及动态脑电图(AEEG)检查,并对其临床与EEG改变进行了相关分析。结果:单纯发作性头痛而无癫发作或癫家族史,若EEG有典型癫样放电、抗癫治疗效果显著,可以诊断为头痛型癫;单纯发作性头痛而无癫发作或癫家族史,尽管EEG有典型癫样放电,但一般药物治疗有效,应诊断为偏头痛或血管性头痛更为合适。结论:EEG检查可为头痛与头痛型癫的筛选、诊断、治疗、转归及预后提供客观依据。 相似文献
10.
T. Hammen F. Kerling M. Schwarz A. Stadlbauer O. Ganslandt B. Keck B. Tomandl A. Dörfler H. Stefan 《European journal of neurology》2006,13(5):482-490
Up to 30% of patients with temporal lobe epilepsy (TLE) remain without remarkable changes in MRI. In this study we investigated the role of (1)H-MR spectroscopy ((1)H-MRS) in lateralizing the affected hemisphere in the mentioned patient group. Twenty-two consecutive patients diagnosed with TLE were investigated by high resolution MRI and (1)H-MRS. We examined the incidence and diagnostic accuracy of temporal metabolite alterations determined by Linear Combination of Model Spectra (L C Model) via water reference. Metabolite values of each hemisphere of TLE patients were compared with healthy controls. Results of metabolite alterations were related to intensive video EEG focus localization. Reduction of N-acetylaspartate + N-acetylaspartyl-glutamate (tNAA) in the affected hemisphere revealed identification in six of nine patients (66%) with unilateral TLE. Group comparison revealed a significant reduction of tNAA (6.1+/-0.8*) in the involved temporal lobe compared with controls (6.67+/-0.4*, P=0.026). Choline levels were significantly increased in the affected hemisphere (1.42+/-0.17*) compared with healthy controls (1.22+/-0.17*, P=0.035). The results of our study show that (1)H-MRS is able to identify the affected hemisphere of MRI negative TLE patients and can be used as an additive tool in multimodal focus localization. 相似文献