糖尿病患者颅神经亚临床损害的瞬目反射及脑干听觉诱发电位研究

目的：探讨瞬目反射及脑干听觉诱发电位(BAEP)对糖尿病患者颅神经亚临床损害的诊断价值。方法：对150例糖尿病患者及50名健康志愿者进行双侧瞬目反射和BAEP检查。结果：瞬目反射和BAEP均检查200人、400侧次，两项检查在糖尿病患者中总的阳性率为31．3％，远高于临床症状、体征的阳性率(6％)。瞬目反射中R2、R2′潜伏期和R1-R2波间期延长最为明显，BAEP的异常则以V波潜伏期延长最常见。结论：瞬目反射与BAEP检查能够可靠的检测糖尿病患者颅神经和脑干受损的早期及亚临床损害。     

痉挛性斜颈脑干听觉诱发电位临床分析

目的探讨痉挛性斜颈患者脑干听觉诱发电位的功能变化。方法比较分析30例痉挛性斜颈患者及30例正常对照患者(颈部向右侧扭转)脑干听觉诱发电位双侧Ⅰ/Ⅴ波高比及Ⅰ～Ⅲ、Ⅲ～Ⅴ波间期的差异。结果病例组脑干听觉诱发电位双侧的Ⅰ～Ⅲ、Ⅲ～Ⅴ波间期正常,斜颈同侧的Ⅰ～Ⅲ波间期较对侧延长,差异有统计学意义(P<0.05);双侧Ⅲ～Ⅴ波间期及Ⅰ/Ⅴ波高比比较差异无统计学意义(P>0.05)。正常对照组颈部向右侧扭转时双侧比较Ⅰ～Ⅲ波间期、Ⅲ～Ⅴ波间期、Ⅰ/Ⅴ波高比比较差异无统计学意义(P>0.05)。结论脑干听觉诱发电位双侧Ⅰ～Ⅲ、Ⅲ～Ⅴ波间期正常提示脑干上部传导通路结构正常,斜颈扭转方向的同侧Ⅰ～Ⅲ波间期较对侧延长提示同侧的传导通路功能异常。     

无定位体征的脑干腔隙性梗塞

部分脑干腔隙性梗塞（腔梗）患者，因无定位体征而常常被误诊为椎基底动脉供血不足（Ｖ－ＢＡＩ）。为了对这些患者作出早期诊断，以利治疗及对预后的估计，对２１例无定位体征的脑干腔梗组（Ａ组）与３０例Ｖ－ＢＡＩ（Ｂ组）患者的临床表现、ＣＴ、ＭＲＩ、经颅多普勒超声（ＴＣＤ）及脑干听觉诱发电位（ＢＡＥＰ）进行比较分析。结果表明：Ａ组以持续症状为主，治疗效果较差，其ＴＣＤ改变不如Ｂ组明显，而ＢＡＥＰ的Ⅲ、Ⅴ波峰潜伏期（ＰＬ）及Ⅲ～Ⅴ波峰间潜伏期（ＩＰＬ）延长比Ｂ组明显。结论：凡症状持续、疗效较差、ＴＣＤ改变不显著而ＢＡＥＰ示听神经中枢段障碍明显者，要高度怀疑脑干腔梗。ＭＲＩ是脑干腔梗可靠而敏感的检查手段。     

脑干血管病的脑干三叉神经诱发电位的研究

目的：探讨脑干血管病的脑干三叉神经诱发电位（BTEP）改变及其临床价值。方法：对28例脑干脑血管（出血12例,梗死16例）进行BTEP检测,同时检测干听觉诱发电位（BAEP）,并结合临床资料进行分析。结果：28例脑干血管病患者BTEP正常7例、异常21例（75％）,其中双侧异常13例、单侧异常8例,异常BTEP主要表现为T3、T5波形消失、波幅低下,或峰潜伏期延长,T1－T3、T1－T5波同期延长,BTEP的变化与病情相关,,且较BAEP更灵敏。结论：BTEP可作为评价脑干血管病引起的脑干细胞损伤的可靠电生理学方法。     

脑干听觉诱发电位在血管性痴呆的应用价值

目的 探讨脑干听觉诱发电位(BAEP)在血管性痴呆患者应用价值.方法 选择200例血管性痴呆患者进行脑干听觉诱发电位(BAEP)检测分析.结果 脑干听觉诱发电位显示研究组III、V波潜伏期(PL)和I～III、III～V、I～V波峰间潜伏期(IPL)及(III～V)/(I～III)比值均高于对照组,差异有统计学意义(P<0.01).结论 脑干听觉诱发电位可客观的反映听觉系统和脑干功能状况,预防疾病进一步发展,对血管性痴呆的临床诊疗及预后均有价值.     

脑干听觉诱发电位在不典型脑干梗死患者中的应用价值

目的探讨脑干听觉诱发电位(BAEP)在不典型脑干梗死患者中的特点及临床价值。方法使用肌电图诱发电位仪对86例不典型脑干梗死患者进行BAEP检查且与其MRI、CT结果比较。结果 86例不典型脑干梗死患者的BA-EP42例异常,异常率48.8%。MRI、CT无1例异常(P<0.01)。结论 BAEP能够间接评估不典型脑干梗死患者的供血情况,给临床诊断与治疗提供客观依据。     

橄榄脑桥小脑萎缩脑干听觉诱发电位研究

本文对３５例橄榄脑桥小脑萎缩（ＯＰＣＡ）患者和３９例正常人进行脑干听觉诱发电位（ＢＡＥＰ）检查，结果发现ＯＰＣＡ病人ＢＡＥＰ异常１５例，阳性率４３％，主要异常是Ⅰ～Ⅲ峰间潜伏期延长和Ⅰ～Ⅴ波潜伏期双耳差值增大（Ｐ＜０．０５），提示ＯＰＣＡ主要电生理异常在听神经至桥脑下段之间，此外，还发现脑干电生理异常率与疾病严重程度和ＣＴ脑干萎缩程度有关。     

后循环短暂脑缺血发作患者BAEP及BR检测报告分析

目的探讨脑干听觉诱发电位（BAEP）和瞬目反射（BR）检查对于后循环短暂脑缺血发作患者脑干功能受损的诊断价值。方法选择66例后循环短暂脑缺血发作患者（TIA组），分别行BAEP和BR检查，观察BAEP波形及各波潜伏期（PL）、峰间潜伏期（IPL），计算BR各成分平均潜伏期，并与40例健康者作对照。结果TIA组中BAEP检出脑干异常48例（72.7％），BR检出脑干异常50例（75.8％），两者联合检测脑干异常60例（90.9％）。结论BAEP与BR均能敏感地反映脑干的病变，两者从不同的解剖路径反映了脑干病变的病理生理基础，有助于定位诊断。     

后循环梗死患者的BAEP、BR、TCR变化的临床意义

目的探讨后循环梗死（PCI）患者脑干听觉诱发电位（BAEP）、瞬目反射（BR）、三叉神经-颈反射（TCR）三种电生理变化。方法选择50例经头颅MRI检查证实为PCI患者,分别行BAEP、BR、TCR检查。BAEP观察其波形,Ⅰ、Ⅲ、Ⅴ峰波潜伏期（PL）、峰波间期（IPL）、波幅（Amp）;BR观察R1、R2、R2’波平均潜伏期、波幅;TCR观察各成分潜伏期、波幅、A值。结果 50例中,BAEP检查异常45例,异常率90%,异常主要表现为Ⅲ、Ⅴ波PL延长,Ⅲ～ⅤIPL大于Ⅰ～ⅢIPL,Ⅰ/Ⅴ波幅大于1。BR检查异常42例,异常率84%,异常主要表现为R1、R2、R2’波PL延长,R2、R2’波幅下降。TCR检查仅5例异常,异常率10%,头颅MRI显示多为延髓梗死。结论 BAEP、BR两种电生理检查方法能较好反映PCI患者脑干功能异常;TCR电生理检查方法异常率低,但对延髓梗死检查有特异性。三者联合应用可提供重要参考价值。     

2型糖尿病对急性脑梗死患者脑干听觉诱发电位及预后的影响

目的探讨2型糖尿病对急性脑梗死患者脑干听觉诱发电位(BAEP)及神经功能的影响。方法选择急性期脑梗死患者154例,包括2型糖尿病合并脑梗死患者(DMCI)74例和非糖尿病脑梗死患者(NDMCI)80例,全部患者发病72h内均行BAEP检查和美国国立卫生院卒中量表(NIHSS)评分。结果 DMCI组与NDMCI组患者BAEP异常率分别为81.2%和63.8%,差异有统计学意义(P0.05);DMCI组患者BAEP主波潜伏期和波间期均较NDMCI组患者明显延长(P0.05);2组患者BAEP异常率与NIHSS评分呈正相关。结论 2型糖尿病加重急性期脑梗死患者脑干功能损伤,BAEP可作为急性期脑梗死患者预后的有效评估指标。     

Electrophysiological brain stem investigations in idiopathic narcolepsy

Narcolepsy is associated with various rapid eye movement (REM) sleep abnormalities. Distinct brain stem areas seem to play a prominent role in REM sleep regulation. Recent magnetic resonance imaging (MRI) studies have led to conflicting findings concerning the presence of structural brain stem lesions in patients with idiopathic narcoleptic syndrome. However, multimodal electrophysiological brain stem investigations may reveal functional brain stem abnormalities even in the absence of MRI abnormality. Therefore we investigated brain stem function in 12 idiopathic narcoleptic patients by systematically studying tegmental brain stem pathways. All of the patients met the diagnostic criteria of the International Classification of Sleep Disorders, with typical changes in polysomnography and the multiple sleep latency test. Electrophysiological investigations comprised masseter reflex, blink reflex, masseter inhibitory reflex, early auditory evoked potentials and electrooculography with vestibular testing. In no patient were electrophysiological brain stem abnormalities observed. Our findings do not support the existence of a relevant brain stem lesion in narcoleptic patients with normal neurological status. Received: 23 September 1997 Received in revised form: 23 January 1998 Accepted: 10 February 1998     

Auditory brain stem response and electrically elicited blink reflex in handicapped children

The auditory brain stem response and the blink reflex were studied in 35 handicapped children in order to evaluate brain stem function. The auditory brain stem response and the blink reflex were abnormal in 20 and 16 cases, respectively. Of these, 14 had both auditory brain stem response and blink reflex abnormalities. The prevalence of auditory brain stem response and blink reflex abnormalities was high in severely handicapped children with difficulty in chewing or swallowing. The blink reflex was abnormal in four of 32 sides with a normal auditory brain stem response and 15 of 23 sides with an abnormal auditory brain stem response threshold, which reflects hearing loss or brain stem dysfunction. We conclude that the combined application of these two noninvasive tests is useful not only to delineate the extent of brain stem lesions but also to determine whether or not patients with an abnormal auditory brain stem response threshold have brain stem dysfunction.     

Auditory brain stem potentials in chronic alcohol intoxication and alcohol withdrawal

Auditory brain stem evoked responses were in unrestrained rats during periods of acute and chronic alcohol intoxication, alcohol withdrawal, and recovery. Acute alcohol administration altered the auditory brain stem potentials by a prolongation of both peak latency and central conduction time, beginning with early peaks. Similar but lesser effects affecting only the latter peaks were observed during chronic alcohol intoxication. By contrast, alcohol withdrawal resulted in a decrease in the peak latencies of auditory brain stem potentials and a facilitation of central conduction time. Recovery of the auditory brain stem potentials to the normal form required at least three to four weeks. The present study provides the first quantitative data, to our knowledge, on manifestations of alcohol tolerance and withdrawal.     

Abnormal cortical and brain stem plasticity in Gilles de la Tourette syndrome

We investigated primary motor cortex and brain stem plasticity in patients with Gilles de la Tourette syndrome. The study group comprised 12 patients with Gilles de la Tourette syndrome and 24 healthy subjects. Patients were clinically evaluated using the Yale Global Tic Severity Scale. We tested cortical plasticity by conditioning left primary motor cortex with intermittent or continuous theta‐burst stimulation in 2 separate sessions. Test stimulation consisted of 20 motor‐evoked potentials recorded from right first interosseous muscle before and after theta‐burst stimulation. We also tested brain stem plasticity by conditioning the right supraorbital nerve with facilitatory electric high‐frequency stimulation delivered at the same time as the late response of the blink reflex or inhibitory high‐frequency stimulation delivered before the late response on 2 separate sessions. Test stimulation consisted of 10 blink reflexes from the right orbicularis oculi muscle before and after high‐frequency stimulation. After intermittent theta‐burst stimulation, motor‐evoked potential amplitudes in healthy subjects increased significantly but remained unchanged in patients. Similarly, after continuous theta‐burst stimulation, motor‐evoked potential amplitudes decreased significantly in healthy subjects but did not in patients. After facilitatory high‐frequency stimulation, the blink reflex late response area in healthy subjects increased, whereas after inhibitory high‐frequency stimulation, it decreased. Conversely, in patients, both interventions left the blink reflex late response area unchanged. The lack of the expected inhibitory and facilitatory changes in motor‐evoked potential amplitudes and blink reflex late response area suggests that abnormal plasticity in the primary motor cortex and brain stem play a role in the pathophysiology of Gilles de la Tourette syndrome. © 2011 Movement Disorder Society     

Bilaterally recorded brain stem auditory evoked responses. Their asymmetric abnormalities and lesions of the brain stem.

Simultaneous bilateral recordings (C3 to A1 and C4 to A2) of brain stem auditory evoked responses have been studied in 67 supratentorial lesions, nine midbrain lesions, 21 intrinsic pontine lesions, and 23 extrinsic compressions of the pons. The responses in supratentorial lesions showed completely normal records. In midbrain lesions, wave V was specifically altered. As wave 1 has been shown to be a far-field seventh nerve potential, and wave V the midbrain potential, waves II to IV can be inferred to originate in the central auditory pathway between the seventh nerve and the midbrain. Alterations of waves II to IV correlated well with localization of pontine lesions, and asymmetric alterations of the bilaterally recorded responses were associated with unilateral lesions of the brain stem auditory pathway and/or lesions of the crossed auditory projections.     

Electrophysiologic study of Fisher syndrome

Electrophysiologic studies were performed on a 6-year-old girl with Fisher syndrome. We recorded several evoked potentials in this patient: visual evoked potentials, auditory brainstem responses, auditory evoked potentials, short-latency somatosensory evoked potentials, blink reflex elicited by photic stimuli (photo-evoked eyelid microvibration), blink reflex elicited by auditory stimuli (auditory evoked eyelid microvibration), and motor nerve conduction velocity. In our study, photo-evoked eyelid microvibration response was not obtainable; laterality was indicated in visual evoked potential and electroencephalographic studies, and the remaining evoked potentials demonstrated normal responses. The results obtained from the brainstem reflex (photo-evoked eyelid microvibration) suggest that the pathologic focus of Fisher syndrome is located in the midbrain, particularly in the pretectum. It is expected that the combined use of these electrophysiologic techniques may facilitate differentiation between Fisher and Guillain-Barré syndromes.     

Experimental study of brain stem infarction in dogs--effect on BAEP, SSEP, blink reflex and EEG of perforator occlusion

Assessment of the lesion in the brain stem by evoked potentials has not been well established. We have already developed a model of brain stem ischemia by occluding the perforators of the posterior cerebral arteries of the dog. The ischemic lesions locates mainly in the ventral side of the midbrain. Using this model, we assessed brain stem function by brain stem auditory evoked potential (BAEP), surface- and depth-recorded (in medial lemniscus) short latency somatosensory evoked potential (SSEP), blink reflex (BR) and electroencephalography (EEG), and investigated the correlation between the electrophysiological abnormalities and the lesion in the brain stem. The studies were performed for 6 hours after perforator occlusion. Furthermore, depth-recorded SSEP and regional cerebral blood flow (rCBF) were measured under induced hypotension by withdrawal of arterial blood. BAEP did not change in 13 of 16 animals. Surface-recorded SSEP remained unchanged in all 6 animals. The results are probably due to the fact that the lesion does not involve the auditory and somatosensory pathways and the accompanying events such as edema does not affect the both pathways. Depth-recorded SSEP remained unchanged after occlusion and did not disappear even when rCBF fell below 10 ml/100 g/min. It may be suggested that the threshold for electrical failure in the brain stem is much lower than that in the cortex. In BR, R1 did not change but ipsilateral R2 became nearly invisible immediately after perforator occlusion in all animals. The fact that the ischemic lesion did not involve the pons and disturbed reticular formation in the midbrain may probably account for the remaining of R1 and the disappearance of ipsilateral R2.(ABSTRACT TRUNCATED AT 250 WORDS)     

Localizing brain stem lesions with brain stem auditory evoked potentials

Based on a survey of brain stem auditory evoked potentials (BAEPs) in animals and humans with localized brain stem lesions compared to the recognizability of BAEP components in normal materials, it was concluded that BAEP examination might localize lesions to a high or low level and diffusely within the brain stem. In 155 patients with multiple sclerosis, vascular disorders or other lesions from a neurological department, the involvement of the brain stem was clinically estimated to be negative, situated at a high or low level or diffuse. Correlation between location of the lesions assessed by clinical versus BAEP examination showed correspondence between negative and diffusely abnormal findings, but not with regard to levels within the brain stem. CT-scanning similarly failed to localize lesions to various levels. This was probably due to poorly circumscribed or widespread lesions. The main value of BAEP in neurological patients was to establish clinically silent lesions, especially in patients with multiple sclerosis and only spinal signs.     

Auditory brain stem evoked potentials: clinical promise of increasing stimulus rate

Auditory brain stem evoked potentials (ABEPs) were recorded from 10 adults and 10 children who where neurologically and audiometrically normal. ABEPs were recorded in response to 75 dB HL clicks presented at rates of 10/sec and 50/sec. Normative values were calculated for amplitude and latency, as well as for inter-peak amplitude ratio and a variety of inter-peak latency differences and interaural differences at the two stimulus presentation rates. Normative values of the effect of increasing stimulus rate were calculated as well. Measures of changes in ABEPs between stimulus rates of 50/sec and 10/sec were the only derived measures that were significantly different between our adult and child normal populations. In addition, 50 patients with various conditions affecting the brain stem were examined. Increasing stimulus presentation rate had a significant effect on detection of abnormality in ABEPs from the patients examined. Measures of changes in ABEPs between stimulus rates of 50/sec and 10/sec seemed to be sensitive to a subset of abnormalities in our patient population. The case histories of the patients indicate that the subset may be impaired synaptic function. Measures of the effect of rate on ABEPs may complement the traditional measures that are primarily sensitive to white matter lesions.     

Visual and brain stem auditory evoked responses in Wilson''s disease

Sensory evoked potentials were studied in 15 patients with Wilson's disease. Thirteen patients were investigated with pattern reversal visual stimulation. A prolonged P 100 latency of the VEP was present in 7 patients. Brain stem auditory responses were evoked in 12 patients. Prolongation of III-V and I-V interpeak latency was found in 8 patients. The evoked potential studies demonstrated subclinical disturbances in optic and caudal brainstem auditory pathways. Further studies are in progress to evaluate the role of these techniques in monitoring the therapy of newly diagnosed cases.