立体定向脑电(stereo-EEG,sEEG)的癫痫间期高频振荡(High Frequency Oscillations,HFOs)与癫痫灶高度相关,广泛用于难治性癫痫切除术前定位中,但HFOs易与高频伪迹等混淆,自动辨识精度低,临床上仍依赖人工辨识,长程sEEG数据量巨大,人工...立体定向脑电(stereo-EEG,sEEG)的癫痫间期高频振荡(High Frequency Oscillations,HFOs)与癫痫灶高度相关,广泛用于难治性癫痫切除术前定位中,但HFOs易与高频伪迹等混淆,自动辨识精度低,临床上仍依赖人工辨识,长程sEEG数据量巨大,人工辨识耗时费力易出错,急需HFOs高精度自动识别方法。考虑sEEG具有非线性、非平稳以及多维sEEG之间具有一致相关性等特点,本文提出基于最小二乘-多维经验模态分解(Least Square-Multivariate Empirical Mode Decomposition,LS-MEMD)的HFOs快速自动识别方法。本文基于临床1680段HFOs和1720段高频伪迹测试了该算法的性能,且与小波变换、经验模态分解等方法比较,证明了所提方法具有更高的准确率和更低的误检率。展开更多
The YDT1625-11 microphone andTeyuer wall-screen type stereomusical system is made by the BeijingKing Cat Acoustics Equipment Factory withmulti-patent technology. It is noted for itsthinness, full range of frequency ba...The YDT1625-11 microphone andTeyuer wall-screen type stereomusical system is made by the BeijingKing Cat Acoustics Equipment Factory withmulti-patent technology. It is noted for itsthinness, full range of frequency bands, andlow distortion The super-thin geontetric form offersconvenience for users. The frequency bandscover a wide acoustic field from low to highfrequencies. The distortion is lower than theinternational first step index, favourable forthe design and manufacture of the acousticsystem. The fine driving system raises therigidity of the diaphragm, the value of dynamicand the radiating conditions of excitationsource.展开更多
Objective: To characterise flash visual evoked potentials(FVEPs) in 20 patient s with Creutzfeldt-Jacob disease (CJD),and assess the relationships between spo ntaneous EEG patterns and the responses to individual stim...Objective: To characterise flash visual evoked potentials(FVEPs) in 20 patient s with Creutzfeldt-Jacob disease (CJD),and assess the relationships between spo ntaneous EEG patterns and the responses to individual stimuli. Methods: We analy sed the shape and time course of periodic sharp wave complexes(PSWCs) and respon ses to 1 Hz flashes. In nine patients, we applied an algorithm based on an autor egressive model with exogenous input (ARX) to estimate responses to individual r andom flashes and their interaction with PSWCs. Results:The FVEPs included P1 an d N1 components in all patients, and the P2 peak in 18. Eight patients showed gi ant FVEPs (N1-P2 > 60 V), all of whom had an MM polymorphism in codon129 of the prion protein gene; in seven cases, the presence of giant FVEPs correlated with a prominent and almost continuous periodic EEG pattern. Giant N1-P2 abnormally spread on the anterior scalp regions, and had a different waveform distribution from that of the PSWCs. In five patients with a normal or slightly enlarged ave rage N1-P2 amplitude, single sweep (ARX) analysis revealed a period of relative refractoriness following individual PSWCs. In four patients with‘giant’FVEPs, the individual responses occurred regardless of the interval between the stimul us and previous PSWC, but their amplitude had an inverse relationship with the i nterval length.Conclusions: Giant responses to flash stimuli are a common findin g in CJD patients (40%of our cases). Single sweep ARX analysis showed that PSWC s were followed by a period of partial refractoriness, which prevented most of t he individual responses to flashes, but not giant FVEPs. The association between prominent spontaneous paroxysms and giant FVEPs suggests that both are due to a common hyperexcitable change favouring neuronal synchronisation. Significance: Our data contribute to clarifying the debated problem of the occurrence of giant FVEPs in CJD and their relationships with the spontaneous periodic EEG pattern.展开更多
文摘The YDT1625-11 microphone andTeyuer wall-screen type stereomusical system is made by the BeijingKing Cat Acoustics Equipment Factory withmulti-patent technology. It is noted for itsthinness, full range of frequency bands, andlow distortion The super-thin geontetric form offersconvenience for users. The frequency bandscover a wide acoustic field from low to highfrequencies. The distortion is lower than theinternational first step index, favourable forthe design and manufacture of the acousticsystem. The fine driving system raises therigidity of the diaphragm, the value of dynamicand the radiating conditions of excitationsource.
文摘Objective: To characterise flash visual evoked potentials(FVEPs) in 20 patient s with Creutzfeldt-Jacob disease (CJD),and assess the relationships between spo ntaneous EEG patterns and the responses to individual stimuli. Methods: We analy sed the shape and time course of periodic sharp wave complexes(PSWCs) and respon ses to 1 Hz flashes. In nine patients, we applied an algorithm based on an autor egressive model with exogenous input (ARX) to estimate responses to individual r andom flashes and their interaction with PSWCs. Results:The FVEPs included P1 an d N1 components in all patients, and the P2 peak in 18. Eight patients showed gi ant FVEPs (N1-P2 > 60 V), all of whom had an MM polymorphism in codon129 of the prion protein gene; in seven cases, the presence of giant FVEPs correlated with a prominent and almost continuous periodic EEG pattern. Giant N1-P2 abnormally spread on the anterior scalp regions, and had a different waveform distribution from that of the PSWCs. In five patients with a normal or slightly enlarged ave rage N1-P2 amplitude, single sweep (ARX) analysis revealed a period of relative refractoriness following individual PSWCs. In four patients with‘giant’FVEPs, the individual responses occurred regardless of the interval between the stimul us and previous PSWC, but their amplitude had an inverse relationship with the i nterval length.Conclusions: Giant responses to flash stimuli are a common findin g in CJD patients (40%of our cases). Single sweep ARX analysis showed that PSWC s were followed by a period of partial refractoriness, which prevented most of t he individual responses to flashes, but not giant FVEPs. The association between prominent spontaneous paroxysms and giant FVEPs suggests that both are due to a common hyperexcitable change favouring neuronal synchronisation. Significance: Our data contribute to clarifying the debated problem of the occurrence of giant FVEPs in CJD and their relationships with the spontaneous periodic EEG pattern.
