创伤后应激障碍患者视觉和听觉诱发电位研究

目的：探讨军人创伤后应激障碍(PTSD)患者视觉诱发电位(VEP)和听觉诱发电位(AEP)的变异及其临床应用价值。方法：应用脑诱发电位仪、症状自评量表(SCL-90)和事件影响量表(IES)对58例军人PTSD患者(患者组)和52名健康军人(对照组)进行VEP和AEP检测以及SCL-90和IES评定，并于治疗3．5个月时进行临床随访。结果：患者组治疗前与对照组比较，VEP的Cz脑区P2和Pz脑区P3波幅显著降低，AEP的Cz脑区P2波幅降低、P3波幅显著增高，Pz脑区P2潜伏期显著延迟；SCL-90总分与IES总分及其大部分因子分显著升高。患者组治疗后，VEP和AEP的变异指标以及SCL-90与IES总分及其各因子分均恢复至正常值范围内；治疗前后VEP和AEP指标变异的差值分别与部分精神症状的减分率呈显著性相关。结论：PTSD患者诱发电位变异特点与精神症状改善相关，有一定的临床应用价值。     

卡马西平对诱发电位的影响及意义

目的研究长期口服卡马西平治疗癫对诱发电位的影响,并讨论其意义。方法选择尚未治疗的癫病人31例作为试验组;以性别、年龄与癫组相匹配的健康正常人26例作为对照组。两组先分别做脑干听觉诱发电位(BAEP)、事件相关电位P300、视觉诱发电位(VEP)和体感诱发电位(SEP),之后癫组开始卡马西平治疗,服药一年后再作上述各项检查。结果癫组病人治疗前各项电生理学指标与正常对照组相比无显著性差异;癫组卡马西平治疗后各项电生理指标与治疗前相比BAEP各波、P300以及VEP的P100波潜伏期均显著延长;SEP的潜伏期无显著变化。结论神经电生理学检查可以早期发现长期服用卡马西平导致的亚临床毒性。     

军人创伤后应激障碍患者认知性电位变化及其与精神症状的关系

目的　探讨军人创伤后应激障碍(PSTD)患者认知性电位(CEP)的特征和治疗缓解后变化及其与精神症状的关系。方法　应用美国Nicolet Bravo型脑诱发电位仪,对 66 例发病期及其 60 例康复期 PTSD患者进行关联性负变(CNV)、视觉诱发电位(VEP)和听觉诱发电位(AEP)测定,并进行症状自评量表(SCL -90)和事件影响量表(IES)评定。结果　患者组发病期与对照组比较,CNV/M1、VEP/P2 和 AEP/N2 潜伏期延迟(P<0.01或0.05),CNV/M2 和AEP/P3 波幅增高(P<0.01),命令信号后负变化(PINV)出现率增高(P<0.01),SCL-90和IES总分及其部分因子分升高(P<0.01),且 CEP指标与 SCL 90 及 IES总分及其部分因子分显著相关(P<0.01 或 0.05)。患者组康复期 CNV/M1、VEP/P2 和 AEP/N2 潜伏期,CNV/M2、AEP/P3 波幅,PINV出现率以及SCL- 90和IES总分及其部分因子分均恢复至正常值内(与发病期比较P<0.01或0.05,与对照组比较 P>0.05)且治疗前后 CEP指标差值与 SCL 90 及 IES总分及其部分因子减分率显著相关(P<0.01或0.05)。结论　CNV、VEP与AEP的变化可能是PTSD的状态标志。     

Difference in P300 latency in two types of leukoaraiosis

P300 examination was performed in patients with periventricular leukoaraiosis and in patients with leukoaraiosis in the centrum semiovale. Ten patients with periventricular leukoaraiosis, ten patients with leukoaraiosis in centrum semiovale and ten age-matched controls without leukoaraiosis were studied. The P300 was measured with an evoked potential recorder using an oddball paradigm. The mini-mental state examination score was significantly lower and the P300 latency was significantly longer in the leukoaraiosis in the centrum semiovale group than in the periventricular leukoaraiosis group and the control group. Leukoaraiosis in centrum semiovale may be related to dementia and the prolongation of P300 latency. Received: 23 April 1997 Received in revised form: 27 June 1997 Accepted: 12 August 1997     

Correlation of electrophysiologic findings in neural muscular atrophy

In a collective of 22 patients (18 adults, 4 children) with the clinical diagnosis of peroneal muscular atrophy the correlation of various neurophysiological parameters was examined. These included electromyography, motor and sensory nerve conduction velocity, visual (VEP), acoustic (AEP) and somatosensory (SEP) evoked potentials and conventional EEG. In all cases we found a high correlation between the findings of nerve conduction velocities and somatosensory evoked responses. Acoustic evoked potentials were examined in 18 cases and showed 10 pathological findings; visual evoked responses were also examined in 18 cases and produced 5 pathological findings. If nerve conduction velocity measurements are possible, SEP examinations are superfluous as they do not provide additional information. On the other hand, VEP and AEP testing is warrented in all cases to document the impairment of central nervous pathways.     

Alteration of early components of the visual evoked potential in amyotrophic lateral sclerosis

Evoked potentials were recorded in three different visual experiments in 14 patients with amyotrophic lateral sclerosis (ALS) and 14 matched control subjects. Control subjects’ evoked potentials (EPs) were characterized by an initial positivity in the 90–140 ms range (P1) at the temporo-occipital site. This component was absent from the group average of the ALS patients as well as the individual patients’ EPs. As the P1 is known to emanate from inferior occipito-temporal areas, this finding provides electrophysiological evidence for a cortical involvement in ALS including visual areas. Received: 9 September 1997 Received in revised form: 18 November 1997 Accepted: 24 November 1997     

Visual evoked potential abnormalities in dementia with Lewy bodies

ObjectivesVisuo-perceptual deficits and visual hallucinations (VHs) are common disturbances in patients with dementia with Lewy bodies (DLB) and those with Parkinson’s disease (PD). In particular, delays in visual evoked potential (VEP), reversed by l-dopa administration, have previously been observed in PD patients. Impairment in metabolic functions of dopaminergic amacrine cells within the inner plexiform layer of the retina has been largely documented and has been posited as the underlying cause of visual and retinal alterations in PD. The aims of the present study were to investigate the presence of VEP abnormalities in DLB patients, as compared to a PD control group, and to assess the presence of significant correlations between neurophysiological measures and clinical symptoms (i.e., presence of visuospatial deficits and/or visual hallucinations).MethodsFifteen DLB patients and fifteen matched PD patients underwent pattern reversal before and after l-dopa administration, and a short neuropsychological assessment.ResultsIn DLB patients, we observed delay of the P100 latency to foveal stimuli in both eyes compared to normative values. Compared to PD, DLB patients showed higher values of the P100 latency for foveal stimulation from the right eye prior to l-dopa administration (p = 0.018). No correlations between VEP alterations, visuo-spatial deficit and visual hallucinations were found.DiscussionOur findings demonstrated a longer P100 delay in DLB than in PD patients, especially along the right visual pathway. In contrast to previous studies, which focused on a dopaminergic pre-geniculate impairment of visual pathways, our evidence suggests that other mechanisms, possibly relying on thalamic involvement, which is known to be dysfunctional in DLB, can interfere with VEP abnormalities.     

Visual evoked potentials and the P300 component in different courses of the posttraumatic vegetative state

The late latency components of visual evoked potentials (VEP) and the component P300 AEP were analyzed to evaluate their informative value in the process of mental function restoration in patient after long-term traumatic coma. VEP components with latencies of 70 to 320 msec were studied in 24 patients. Topographical mapping of the power of the study VEP components and components P300 was made by the peak amplitude. Long-term VEP components and component P300 were examined by the method of three-dimensional localization of equivalent dipole sources. In 16 patients with positive tendencies in the condition there was a stable localization of the maximum VEP power in the parietal, sagittal, and occipital regions, component P300 showed its maximum amplitude in the central and parietal regions in the left hemisphere. Eight patients with negative tendencies in the status had the maximum VEP and component P300 in the frontal and temporal regions, predominantly in the right hemisphere. The paper shows it important to evaluate not only time-amplitude parameters and analyzes the tomographic features of its formation in dynamics.     

Evoked potential correlates of Post-Traumatic Stress Disorder in refugees with history of exposure to torture

The presence and magnitude of information processing deviations associated with Post-Traumatic Stress Disorder (PTSD) are far from being well-characterized. In this study we assessed the auditory and visually evoked cerebral responses in a group of Iraqi refugees who were exposed to torture and developed PTSD (N = 20), Iraqi refugees who had been exposed to similar trauma but did not develop PTSD (N = 20), and non-traumatized controls matched for age, gender, and ethnicity (N = 20). We utilized two paired-stimulus paradigms in auditory and visual sensory modalities, respectively. We found significantly smaller amplitudes of both the auditory P50 and the visual N75 responses in PTSD patients compared to controls, reflecting decreased response to simple sensory input during a relatively early phase of information processing (interval 50–75 ms post stimulus). In addition, deficient suppression of the P50/N75 response to repeating stimuli at this early stage in both modalities is indicative of difficulty in filtering out irrelevant sensory input. Among associations between electrophysiological and clinical measures, a significant positive correlation was found between dissociation score and P50 S1 amplitudes (p = 0.024), as well as stronger auditory P50 gating correlated with higher quality-of-life index scores (p = 0.013). In addition, smaller amplitudes of N150 visual evoked response to S1 showed a significant association with higher avoidance scores (p = 0.015). The results of this study highlight the importance of early automatic auditory and visual evoked responses in probing the information processing and neural mechanisms underlying symptomatology in PTSD.     

The spectrum of Jansky-Bielschowsky disease.

A series of five patients with a variant type of Jansky-Bielschowsky disease is presented. The disease initiated between four and a half and seven years with mental and slight motor symptoms. The additional neurological symptoms and signs, i.e. visual failure, retinal degeneration, ataxia, myclonia and epilepsy developed in all children before the age of ten years. The present series differs from our previous series of 16 cases especially in regard of neurophysiological findings (photic spikes, high visual evoked potential, VEP and high somatosensory evoked potential, SEP). VEP became abnormally high between 8.0 and 9.5 years instead of being an early finding as in the previous series. Photic spikes appeared also later in the present series. Electromicroscopic investigation revealed cytosomes with fingerprint profiles (FP) in the autonomic ganglion cells and cytosomes with both FP and curvilinear (CP) profiles in many extraneural cells including smooth muscle, Schwann cells, capillary endothelium and macrophages. In the light of our 21 Finnish patients and the literature, the spectrum of Jansky-Bielschowsky disease seems to be much wider than previously assumed. The diagnosis should be based on clinical, ophthalmological, neurophysiological and ultrastructural findings. Repeated neurophysiological studies may be necessary.     

Neurophysiological and CSF immunological study of 19 patients affected by acute idiopatic optic neuritis

We studied 19 patients affected by acute idiopatic optic neuritis (ON), with neurophysiological tests: visual (VEP), somatosensory (SSEP), acoustic (ABR) evoked potentials and study of the blink reflex (BR), and with cerebrospinal fluid (CSF) examination, in order to detect "silent" lesions in the central nervous system (CNS) and/or immunological alterations, suggestive of multiple sclerosis (MS). The percentage of cases with at least one altered CSF IgG parameter (IgG index, IgG synthesis/day and IgG oligoclonal bands) has been higher than that of cases with one or more altered neurophysiological tests, regardless of the apparently intact eye VEP. If we also included this last test, the 2 percentages become identical. The validity of these tests in predicting the evolution of ON in MS is discussed.     

术中视觉诱发电位监测对视觉通路保护的研究

目的对累及视路的肿瘤,术中应用视觉诱发电位(VEP)监测技术,监测视路的传导功能,为保护术后视觉功能提供实时的电生理传导依据。方法对16例累及视路的颅内肿瘤及颅骨病变,术中监测视觉诱发电位,比较术中视觉诱发电位变化和术后视力改变的关系。结果(1)12例引出稳定、可重复的VEP电位。其中3例术中VEP波幅上升50%以上,潜伏期缩短10%,术后视力均较术前明显提高;5例术中VEP波幅下降小于50%,潜伏期延长10%以内,术后视力轻度下降3例,明显下降1例,基本同前1例;4例VEP波幅下降大于50%,潜伏期延长10%以上,术后视力明显下降3例,轻度下降1例。(2)4例术中未引出VEP,术后视力均明显下降。(3)术中VEP波幅下降大于和小于50%的两组,术后视力明显下降率经X2检验,P<0.05,差异有统计学意义。结论视觉诱发电位监测可以术中及时发现视路的传导功能,为术者判断视觉功能提供了客观、实时的电生理传导依据。VEP波幅下降50%可以作为视路传导功能严重受损、术后视力可能严重下降的警戒参考点。     

不同类型急性脑卒中患者视觉诱发电位分析

目的观察急性脑卒中患者视觉诱发电位（VEP）改变特点,评价其对于脑功能监测的价值。方法对58例脑梗死、27例脑出血和11例蛛网膜下腔出血患者,检测发病后不同时期（1～12d）VEP和血清神经元特异性烯醇化酶（NSE）改变,结合中国卒中量表评分（CSS）、Barthel指数、Glasgow—Pittsburgh昏迷量表评分以及颅脑影像学检查结果,分析与临床神经功能缺失的关系。25例年龄和性别匹配的正常人作为对照。结果幕下脑出血患者视觉诱发电位（VEP）异常率显著高于幕上脑出血患者（P〈0．01）,后循环脑梗死患者VEP异常率显著高于前循环脑梗死患者（P〈0．01）;脑出血患者VEP—P100峰潜伏期与其血清NSE水平及CSS评分呈正相关（P〈0．01）。结论急性脑卒中患者VEP异常变化可客观反映病情严重程度和病情变化,对后循环病变价值较大。     

Effects of visual contrast on visual evoked potentials and Doppler signal

We studied visually evoked cerebral blood flow responses (VEFR) and visual evoked potentials (VEP) to different visual contrasts and analysed the relationship between them. The records were made from 35 healthy volunteers aged 38.6 +/- 10.1 years. The stimulus was a black-and-white checkerboard with visual contrasts (VC) of 1%, 10% and 100%. The VEFR were measured in the posterior cerebral artery using transcranial Doppler, and the VEP were recorded from the occipital leads. We found the relationship between visual contrast and VEFR (r = 0.79, P < 0.01) as well as between visual contrast and VEP (r = 0.71, P < 0.01). We also found moderate association between the VEP and the VEFR (r = 0.69, P < 0.01). The analysis of the regression slopes between two different age subgroups (P < 0.01) did not show a significant difference (P = 0.020). We concluded that a simultaneous recording of VEFR and VEP to visual contrasts could allow an assessment of neurovascular coupling in humans.     

Dissecting the cellular contributions to early visual sensory processing deficits in schizophrenia using the VESPA evoked response

Electrophysiological research has shown clear dysfunction of early visual processing mechanisms in patients with schizophrenia. In particular, the P1 component of the visual evoked potential (VEP) is substantially reduced in amplitude in patients. A novel visual evoked response known as the VESPA (Visual Evoked Spread Spectrum Analysis) was recently described. This response has a notably different scalp topography from that of the traditional VEP, suggesting preferential activation of a distinct subpopulation of cells. As such, this method constitutes a potentially useful candidate for investigating cellular contributions to early visual processing deficits. In this paper we compare the VEP and VESPA responses between a group of healthy control subjects and a group of schizophrenia patients. We also introduce an extension of the VESPA method to incorporate nonlinear processing in the visual system. A significantly reduced P1 component was found in patients using the VEP (with a large effect size; Cohen's d=1.6), while there was no difference whatsoever in amplitude between groups for either the linear or nonlinear VESPA. This pattern of results points to a highly specific cellular substrate of early visual processing deficits in schizophrenia, suggesting that these deficits are based on dysfunction of magnocellular pathways with parvocellular processing remaining largely intact.     

支架置入术对椎基底动脉系统短暂性脑缺血发作患者诱发电位的影响

目的 观察支架置入术能否改善椎基底动脉系统短暂性脑缺血发作（TIA）患者的亚临床症状。方法 11例症状性椎基底动脉狭窄的椎基底动脉系统TIA患者,支架置入术前后分别检测体感诱发电位（SEP）、脑干听觉诱发电位（BAEP）、视觉诱发电位（VEP）,记录各诱发电位的潜伏期及波幅。结果 （1）术前诱发电位均异常,主要表现为SEP N20及P40潜伏期异常,BAEPⅠ、Ⅲ、Ⅴ波潜伏期延长,VEP P100潜伏期延长。（2）与术前相比,术后1周BAEP表现为Ⅰ～Ⅲ波潜伏期缩短（P =0.046）、Ⅲ波幅升高（P =0.05）;SEP表现为N20潜伏期缩短（P =0.012）,N13～N20间期缩短（P =0.013）,P14～N20间期缩短（P =0.005）;VEP表现为 P100潜伏期缩短（P =0.022）。结论 支架置入术后,椎基底动脉系统TIA患者的SEP、BAEP、VEP好转,提示患者的亚临床症状恢复。     

The nervous system in early HIV infection: a prospective study through 7 years

In this study 28 patients with early stage HIV infection (CD4 >280 x 10(6)/l) were subjected to yearly examinations of the nervous system up to 7 years in order to detect any deterioration. Clinical neurological as well as neuropsychological performance was evaluated. The patients also underwent yearly neurophysiological tests (digital EEG, visual evoked potentials, somatosensory evoked potentials, auditory evoked potentials P300 and electroneurography). Every other year, SPECT with (99m)Tc-D,L-hexamethylpropylene amine oxime and brain MRI were performed. Originally, 38 patients were included in the study but only the results of 28 patients who complied with three of more yearly check-ups are presented. The results of yearly investigations of cerebrospinal fluid (CSF) have been presented earlier [Eur J Neurol4 (1997) 1]. All the patients showed signs of HIV in the CSF. Yet, no major deterioration in the neurological, psychological performance, neurophysiological or neuroimaging examinations could be discerned.     

Evoked potentials predict psychomotor development in neonates with normal MRI after hypothermia for hypoxic-ischemic encephalopathy

Objectives

To assess the prognostic role of evoked potentials (EP) in neonates with normal magnetic resonance imaging (MRI) after therapeutic hypothermia (TH) for hypoxic-ischemic encephalopathy (HIE).

Evaluation of preclinical onset in patients with the childhood form of cerebral adrenoleukodystrophy--usefulness of visual cognitive function and evoked potential tests

We examined both visual evoked potential (VEP) and neuropsychological tests in 18 patients with X-linked adrenoleukodystrophy (ALD). Patients consisted of 10 boys with apparent lesions in the posterior white matter on MR imaging, 3 with lesions in the frontal white matter area and 5 that were neurologically asymptomatic with no apparent brain MRI abnormalities. Almost all patients with posterior WM lesion showed patterns of lower PIQ than VIQ on WISC-III and lower scores on scales for simultaneous processing than for sequential processing on Kaufman Assesment Battery for Children (K-ABC). Four of 5 asymptomatic patients showed PIQ/VIQ patterns similar to those in the posterior group. Patients with a difference more than 13 between PIQ and VIQ also showed poor results on Frostig developmental test of visual perception (DTVP). There was a prolongation of the peak latency of P100 on flash VEP in many patients with posterior whitematter lesions, however, asymptomatic patients did not show any abnormality of P100 latency but there was an increased amplitude of N75-P100 on flash and pattern reversal stimuli VEP. One patient with abnormally high VEP (31.4 microV; + 3.6 SD) gradually improved to the normal range (11.4 microV; 0SD) after hematopoietic stem cell transplantation. These cognitive and neurophysiological examinations could be useful in the detection of preclinical onset of childhood ALD before the appearance of MRI lesions on MRI.     

Menkes'' disease: neurophysiological aspects.

The evolution of neurophysiological features including the electroencephalogram (EEG), electroretinogram (ERG), and visual evoked potentials (VEP) is reported in eight cases of Menkes' "kinky hair" disease. All EEGs were severely abnormal, with some characteristic features seen from 3-5 months of age, after the onset of clinical symptomatology. From the age of 5 months, the EEGs resembled hypsarrhythmic patterns. The ERG was not affected in any patient, but the VEP was either of low amplitude or completely absent in all but one of the six patients tested. All eight patients received copper injections without substantial effect on either the clinical course of the disease or the EEG features.