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。     

Source derivation of the brain-stem auditory evoked potential

This study described the results of applying source derivation to the brain-stem auditory evoked potential. Unilateral stimulation gives rise to current sinks, associated with waves I and III, which are located in the vicinity of the ipsilateral mastoid. Waves II and V are associated with a pair of current sinks which appear bilaterally in the vicinity of each mastoid.     

The relation between visual hallucinations and visual evoked potential in Parkinson disease

OBJECTIVE: The pathophysiology of hallucinations in Parkinson disease is poorly understood. This study investigated the relation between visual hallucination and visual evoked potentials (VEPs) in Parkinson disease. METHODS: Nineteen patients with Parkinson disease were studied. The authors divided patients into 2 groups: patients with visual hallucinations (VH group) and those without visual hallucinations (no-VH group). VEPs using a checkerboard stimulus were recorded under a drug-free state. RESULTS: On multivariate regression analysis, only the average P100 latency was selected and remained significant after the backward elimination method. CONCLUSION: The authors demonstrated a close association between visual hallucinations and elongated VEP latency in Parkinson disease. VEPs may become one of the predictors for visual hallucination.     

Maturation of the brain-stem auditory evoked potential in premature infants

Patterns of development and extent of variability of the brain-stem auditory evoked potential (BAEP) are described in 52 healthy premature infants and 50 normal term newborns with reliable conceptional ages. Binaural and monaural stimulation are compared. Serial studies of individual prematures are emphasized and demonstrate that the most consistent and least variable measures are the monaurally derived interpeak intervals. All the BAEP parameters studied mature including wave form, relative amplitude, peak and interpeak intervals, but there is far more variability in preterms than in term infants or adults, even when infants are carefully matched for conceptional age. As term is approached, BAEP variability decreases substantially, suggesting that near term the BAEP becomes a more reliable indicator of neurologic function. The variability of the BAEP in the normal preterm limits its usefulness in determining neurologic dysfunction in individual high risk infants. Nevertheless, the BAEP may still prove useful for defining group differences among infants and could provide an objective measure of those factors influencing neurologic development. Serial change in the BAEP is a specific parameter which we believe merits further study in premature infants as an index of neurologic maturation.     

Neuroanatomic correlations with the late waves of the brain-stem auditory evoked potential

The goal of this study was to investigate the neuroanatomic correlations of the late waves (VI-VIII) of the BAEP. Patients (N = 55) with clinical evidence of a CVA were compared to a normal control group (N = 85). Latencies of greater than 3 S.D. from the means of the normal group were considered abnormal. CT and MRI scans provided evidence of the lesions. For the 14 patients who had normal BAEPs, the sizes of lesions were significantly smaller than for those with abnormal tests. Evidence shows that an abnormal wave VI was related to an ipsilateral cortical lesion and an abnormal wave VIII was related to a lesion in the internal capsule-corpus striatum.     

Does selective attention influence the brain-stem auditory evoked potential?

We have re-examined the problem of selective attention in relation to brain-stem auditory evoked potentials (BAEPs). We compared BAEPs recorded in the relaxed individual with those elicited during visual attention and during auditory attention. Particular emphasis was placed on the use of a demanding visual task to ensure appropriately sustained levels of concentration by the subject for the durations of the tests. We measured the latency of wave I, the wave I-V interval and the amplitudes of waves I and V in 16 subjects in each of the conditions but could find no effect attributable to changes in states of attention. We conclude that there is no evidence for the actions of gating or switching mechanisms at early stages of the auditory pathways.     

Magnetic resonance imaging and brain-stem auditory evoked potentials in neuro-Behcet's disease

We studied central nervous system lesions in patients with neuro-Behcet's disease using magnetic resonance imaging (MRI) of the brain and recording of brain-stem auditory evoked potentials (BAEPs). MRI revealed abnormal findings in seven of eight patients. MRI studies demonstrated extensive regions with high intensity signal in the brain stem and/or basal ganglia on T2-weighted images obtained during the acute stage of the disease in three patients. One of these patients had a strongly gadolinum-enhanced round lesion in the lower pons. In four of the other five patients with chronic disease, brain-stem atrophy was observed on T1-weighted images. Atrophic changes were more severe in the brain stem than in the cerebellum. Abnormal BAEPs were observed in three patients and consisted of prolongation of interpeak latency of waves III-V and defects of wave III or V. Abnormal BAEPs were recorded in patients with severe inflammatory changes or progression of atrophic changes in the brain stem. Our findings show that MRI and BAEPs are useful in detecting the presence and assessing the degree of neurological involvement in patients with neuro-Behcet's disease.     

Emergence of the brain-stem auditory evoked potential in the premature lamb.

Brain-stem auditory evoked potentials (BAEPs) were elicited by bone conducted stimuli in the very immature lamb following delivery, wherein liquid ventilation techniques were utilized to control cardiopulmonary and acid-base conditions, independent of umbilical-placenta support. Unlike previous studies of the in utero fetal lamb in which the BAEP could not be elicited by earphone delivered stimuli until 117 days gestation, our results demonstrate that the BAEP emerges at least as early as 106 days gestation in the lamb and consists of a full complement of readily discernible and reproducible wave forms. In addition, the results demonstrate substantial maturation of the BAEP from 106 to 122 days gestation during which time there is a significant decrease in absolute and interpeak latencies with an increase in developmental age. It is concluded that the ability to elicit the BAEP utilizing bone conduction at this early stage of gestation is related to improved stimuli delivery. Furthermore, this study demonstrates the feasibility and flexibility afforded by liquid ventilation and bone conduction BAEP techniques to study brain-stem function at particularly vulnerable stages of development.     

创伤后应激障碍患者的脑干诱发电位分析

目的：探讨创伤后应激障碍（PTSD）患者的脑干听觉诱发电位（BAEP）变异特点及其与心身症状的关系。方法：对54例PTSD患者进行BAEP检测和心身症状评定,分析BAEP与心身症状的相关性,并与健康人作比较。结果：PTSD患者Pz脑区Ⅲ、Ⅴ波绝对潜伏期和Ⅰ～Ⅲ波间期均延迟,Ⅲ～Ⅴ波间期缩短,Ⅴ／Ⅰ波波幅比下降;症状自评量表（SCL-90）的总分及其躯体化、强迫、抑郁、焦虑因子分,事件影响量表（IES）的总分及其回避、闯入因子分显著高于对照组;Pz脑区BAEP各波的观察指标与大部分心身症状的相关有显著性意义。结论：BAEP检测为PTSD患者的临床辅助诊断提供了一种敏感、客观的电生理学手段。     

Normal brain-stem auditory evoked potentials with abnormal latency-intensity studies in patients with acoustic neuromas

Brain-stem auditory evoked potentials (BAEPs) are highly sensitive for detecting acoustic neuromas but false-negative results occur. We studied BAEPs preoperatively in 39 cases of acoustic neuroma. Absolute and interpeak latencies ipsilateral to the tumor, and interaural latency differences, were normal in four patients with small tumors. In three of these, however, results of latency-intensity studies were abnormal. In one patient, the latency-intensity result became normal postoperatively. If acoustic neuroma is suspected, and BAEPs are normal by usual criteria, latency-intensity functions should be examined to maximize chances of detecting a small tumor.     

Processing and analysis techniques for brain-stem auditory evoked potentials with localization of brain-stem lesions

A computer assisted method of exact automatic measurement of BAEPs, mainly for the purpose of localization of brain-stem lesions, is described. The method presents analogue curves with superimposed confidence regions for the amplitudes and peak latencies of separate waves. The numerical output presents peak latencies, amplitudes, interpeak time intervals and central conduction times, all with normative values (60 healthy subjects), and +/- 2 and +/- 3 S.D. intervals and automatic labelling of pathological parameters (outside the chosen statistical limits). With the exception of the identification of separate waves in the often greatly distorted pathological BAEP the whole processing and display of the results are fully automatic.     

Correlation between a unilateral midbrain-pontine lesion and abnormalities of brain-stem auditory evoked potential

Brain-stem auditory evoked potentials (BAEPs) were evaluated over a 39 day period in a patient with a unilateral pontine-midbrain lesion verified by CAT scan and at autopsy. Waves I, II and III were present on the side of lesion, whereas all 5 waves were present on the side opposite the lesion. The findings suggest that the BAEPs may be obtained with only an intact ipsilateral auditory pathway. Crossing fibers in the trapezoid body also appear to make contributions to the normal generation of wave V.     

Effects of cocaine on the brain-stem auditory evoked potential in the Long-Evans rat

The present study examined the effects of an acute psychoactive dose of cocaine hydrochloride (HCl) in the rat, using the brain-stem auditory evoked potential (BAEP) as an objective, quantitative measure of this substance's effects on brain and auditory electrophysiology. The animals were 8 adult Long-Evans rats (4 female, 4 male). BAEPs were recorded from skull screw electrodes during a baseline period as well as 30-90 min after cocaine HCl treatment (10 mg/kg, i.p.). Normothermia was maintained to control for possible temperature-related effects. Cocaine's effects on the BAEP were examined over a broad range of stimulus intensities (intensity profiles) and repetition rates (rate profiles). Cocaine prolonged latencies of several BAEP components at low stimulus intensities and shortened these latencies at high stimulus intensities. The average BAEP threshold was also increased by cocaine treatment. These results were not strong, but were suggestive of a recruitment type change in auditory function. Cocaine treatment had no convincing effects on the BAEP as a function of stimulus repetition rate.     

Brain-stem auditory evoked potential abnormalities with unilateral brain-stem lesions demonstrated by magnetic resonance imaging

We correlated the brain-stem auditory evoked potential (BAEP) abnormalities in 24 patients with discrete unilateral brain-stem lesions demonstrated by magnetic resonance imaging. In 18 patients who had BAEP abnormalities either confined to or more severe on stimulation of one ear, the lesion on magnetic resonance imaging was in the brain stem ipsilateral to the corresponding ear. Mesencephalic lesions produced amplitude abnormalities of the IV/V complex while pontine lesions resulted in abnormalities of earlier components (wave II and/or III). Prolongation of the I-III interpeak latency tended to occur with pontine lesions and of the III-V interpeak latency with mesencephalic lesions. Unilateral brain-stem lesions, particularly at the mesencephalic level, often produced BAEP abnormalities on both ipsilateral and contralateral monaural stimulation.     

Effect of L-dopa on visual evoked potential in patients with Parkinson's disease

In 47 patients with Parkinson's disease, we studied the visual evoked potential (VEP) using the pattern-reversal checkerboard (CBVEP) and the grating (GVEP) stimuli before and after 3 months of L-dopa therapy. The P100 latency in both CBVEP and GVEP was prolonged before L-dopa therapy, usually commensurate with the degree of motor disability. Clinical improvement of the parkinsonian state after L-dopa therapy was associated with shortening of the P100 latency in CBVEP, but not significantly in GVEP.     

59例听神经瘤患者脑干听觉诱发电位分析

目的 分析听神经瘤(acoustic neuroma,AN)患者的脑干听觉诱发电位的变化特征及健侧耳峰间期改变.方法 对59例听神经瘤(AN)患者进行脑干听觉诱发电位(BAEP)检测,测定Ⅰ、Ⅲ、Ⅴ波潜伏期(PL)、峰间期(IPL),双耳PL、IPL之间差值(ILD)等数值.结合MRI、CT影象学资料进行分析,并与36例健康者对照.结果 AN组与正常对照组BAEP各波PL、IPL测值比较差异有极显著性(P＜0.01).AN患侧BAEP异常率98.3%(58/59);主要表现:①Ⅰ、Ⅲ、Ⅴ波缺失;②Ⅲ、Ⅴ波PL延长;③Ⅰ～Ⅲ、Ⅲ～Ⅴ、Ⅰ～Ⅴ波IPL延长.AN患者健侧BAEP的异常率69.5%(41/59),主要表现:①Ⅴ波PL延长;②Ⅲ～Ⅴ及Ⅰ～Ⅴ波IPL延长;③Ⅲ～Ⅴ/Ⅰ～Ⅲ波IPL比值＞1.肿瘤直径＞2cm,BAEP的异常率有显著提高.不同大小肿瘤组间健侧BAEP测值比较:健侧Ⅴ波PL差异有显著性(P＜0.05),Ⅲ～Ⅴ及Ⅰ～ⅤIPL差异有极显著性(P＜0.01).结论 BAEP对AN诊断具有重要意义,它为病变提供了定位诊断依据,尤其健侧Ⅲ～Ⅴ/Ⅰ～Ⅲ波IPL比值异常,是脑干受压的敏感指标.     

脑干听觉诱发电位在小脑卒中应用的价值探讨

对２８例小脑卒中患者进行脑干听觉诱发电位（Ｂｒａｉｎｓｔｅｒｎａｕｄｉｔｏｒｙｅｖｏｋｅｄｐｏｔｅｎｔｉａｌ，ＢＡＥＰ）检测研究，其中小脑出血１９例，小脑梗塞９例，结果发现：ＢＡＥＰ在小脑卒中的异常为８５．７１％，且主要发生在病灶侧，部分病例可累及双侧。主要以Ⅲ，Ⅴ波ＰＬ及Ｉ～Ⅲ，Ｉ～ⅤＩＰＬ延长，ＢＡＥＰ在出血及梗塞的定性上无参考价值，随着病情的好转，ＢＥＡＰ亦逐渐恢复正常。     

Age-dependent amplitude variation of brain-stem auditory evoked potentials

Normative amplitude values of brain-stem auditory evoked potential (BAEP) components are given for normally hearing subjects at 1, 10, 30, 50 and 70 years of age, with an intragroup age variation of only +/- 6 months. Under these circumstances amplitude standard deviations decreased to less than 20% of the mean values. In contrast with the reduced evolution of latency with age, BAEP amplitude (for components I-V) undergoes a greater oscillation during ontogeny. With the exception of component I, it increased markedly from 1 year to 10 years of age and decreased thereafter constantly up to 50 years, with a mean rate of 10 nV yearly. The decrease slowed down between 50 and 70 years. The amplitude differences between the subgroups are highly significant statistically (P less than 0.01). Possible reasons for these changes are discussed.