Brainstem auditory evoked potentials in postconcussion syndrome

Brainstem auditory evoked potentials (BAEPs) were recorded from 55 patients with postconcussion syndrome (PCS) to elicit evidence of an organic and subclinical brainstem disorder. Fifteen patients (27.3%) showed abnormal responses unilaterally or bilaterally, especially for one or more interpeak latencies prolonged beyond the upper 99% confidence limits. Other 9 patients had borderline responses. The BAEP alterations were not correlated either with dizziness at the time of recording, or with vestibular troubles in the routine caloric test. Though BAEP abnormalities may be present a long time after injury, we found an improvement of responses in the majority of 14 re-tested patients. These data show that BAEP can give an objective demonstration of a reversible brainstem disorder in patients with PCS.

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Sommario I potenziali evocati acustici del tronco cerebrale (BAEP) sono stati registrati in 55 pazienti affetti da sindrome soggettiva postcraniotraumatica (PCS), per evidenziare un possibile danno organico subclinico del tronco cerebrale. Quindici pazienti (27.3%) hanno mostrato risposte alterate unilateralmente o bilateralmente, soprattutto a causa della presenza di una o più latenze interpicchi oltre i limiti fiduciali superiori del 99%. Altri 9 pazienti hanno mostrato risposte borderline. Non sono state ritrovate correlazioni tra il reperto di BAEP alterati e la presenza di vertigini all'atto dell'esame, né con il comportamento dell'esame vestibolare. Benché le alterazioni del BAEP si possano osservare anche a distanza di molti mesi dal trauma, la maggioranza dei pazienti con BA EP alterati, ad un secondo esame ha mostrato un miglioramento della risposta. Tali dati dimostrano che i BAEP sono in grado, in alcuni pazienti affetti da PCS, di evidenziare un danno organico del tronco cerebrale, passibile di regressione.

     

Prognostic evaluation of brainstem hematomas: the role of CT scan and brainstem auditory evoked potentials

Abstract– 6 cases of brainstem hematoma were studied utilizing CT scan and brainstem auditory evoked potential (BAEP) recordings. CT scan did not contribute to an early discrimination between primary and secondary hematomas. Size of the hematoma and the presence of blood in the CSF did not represent evident signs in differentiating benign from unfavourable brainstem hematomas or hemorrhages. BAEP recordings showed the presence of electrophysiological anomalies at the level of the lesion, demonstrating that bleeding as well as tumor in the brainstem can provoke a focal damage.     

Contralateral evoked brainstem auditory potentials as an indicator of intraoperative brainstem manipulation in cerebellopontine angle tumors

Abstract

Brainstem auditory evoked potentials (BAEP) were studied during operations to remove acoustic tumors using the retromastoid approach. BAEP were elicited from the side contralateral to the tumor, and changes in the latencies of peaks III and V of the BAEP were compared with changes in cardiovascular parameters throughout the operation. When the changes in the determined cardiovascular parameters were related to surgical manipulations, the related changes in the latencies of peaks III and V of the BAEP were more consistent than the changes in the cardiovascular parameters and they tended to occur earlier than the changes noted in the cardiovascular parameters. [Neurol Res 1996; 18: 528-540]     

Brainstem auditory evoked potentials in tuberous sclerosis

Brainstem auditory evoked potentials were recorded in 4 subjects and pattern reversal evoked potentials in 1 subject, all with tuberous sclerosis. Alterations were found (absence or delay of components and prolonged interpeak intervals) which may suggest impaired nervous conduction also at brainstem level in patients with tuberous sclerosis.

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Sommario Sono stati registrati i potenziali evocati auditivi troncoencefalici in 4 soggetti con sclerosi tuberosa, in uno di essi sono stati registrati anche i potenziali evocati visivi da pattern reversal. Sono state ritrovate alterazioni delle risposte (assenza o ritardo di alcune componenti ed intervalli interpicco prolungati) che possono suggerire l'esistenza di una conduzione nervosa alterata anche a livello del tronco dell'encefalo nei pazienti con sclerosi tuberosa.

     

Visual and auditory evoked potentials in the early diagnosis and follow-up of neurosarcoidosis

Visual and brainstem auditory evoked potentials (VEPs, BAEPs) were recorded in 23 patients with neurosarcoidosis. Eight patients (35%) had abnormal BAEPs, and 10 (43%) had abnormal VEPs. Four of the 8 patients with abnormal BAEPs had facial paresis, one had impaired memory and only 3 had symptoms and signs compatible with brainstem lesion. Seven of the patients with abnormal VEPs had no visual symptoms. These findings suggest that BAEP and VEP can reveal subclinical nervous system involvement in sarcoidosis and can also help in the early diagnosis of neurosarcoidosis. Successive recordings of 5 patients showed that BAEP and VEP were useful in the follow-up of these patients.     

Changes in auditory P300 event-related potentials and brainstem evoked potentials in diabetes mellitus

To investigate the influence of diabetes mellitus on higher cognitive functions electrophysiologically, we studied auditory P300 event-related potentials (P300) in 40 NIDDM patients, taking into account wave I-V latencies (I-V) in auditory brainstem evoked potentials, clinical parameters and head MRI findings. Compared with 20 controls, diabetics had significantly longer P300 and I-V latencies. P300 latencies in diabetics correlated with neither I-V. HbA₁, blood glucose levels, nor disease duration. Of the 13 diabetics investigated neuroradiologically, four had lacunar infarcts with prolonged electrophysiological values. The remaining nine had normal MRI scans, but their physiological parameters were still significantly longer than those of controls. These findings suggest that NIDDM can independently alter higher cognitive and the central auditory pathway functions. Our data also suggest that these alterations occur regardless of the recent metabolic derangement and disease duration. Cerebrovascular ischemia, if present, also appears to contribute in part to cognitive alterations.     

精神发育迟滞的脑体感诱发电位（附50例分析）

作者对５０例诊断为精神发育迟滞儿童进行体感诱发电位（ＳＥＰ）检查，将其结果与临床资料、ＥＥＧ、智商及脑ＣＴ扫描作对照研究。结论认为ＳＥＰ对精神发育迟滞儿童的诊断有重要意义，异常率达８２％，无创伤，无痛苦，亦可作为观察疗效和估价预后的一项客观指标，较一般常规的客观神经系统检查更敏感。     

Detection of brainstem lesions in multiple sclerosis: comparison of brainstem auditory evoked potentials with nuclear magnetic resonance imaging

Topographical information provided by brainstem auditory evoked potentials (BAEPs) was investigated in 43 patients by comparison with cerebral nuclear magnetic resonance imaging (NMR). Lesions in the region of the brainstem auditory pathways were demonstrated by BAEPs in 44.2%, and in 39.5% by NMR. As regards brainstem levels, in 15/21 (71.4%) with abnormal findings at least one lesion was verified by NMR-matched BAEP results. The study confirms the topographical information provided by the BAEPs on the different levels of the brainstem, but not the assumption that generation of the BAEPs is predominantly ipsilateral. BAEPs retain their importance for the detection of disseminated lesions in the diagnosis of multiple sclerosis (MS) in the era of expensive imaging methods.     

脑干听觉诱发电位及体感诱发电位在重型颅脑损伤患者预后评估中的作用

目的 分析探讨脑干听觉诱发电位(BAEP)及体感诱发电位(SEP)与重型颅脑损伤病人预后的关系.方法 对33 例重型颅脑损伤患者早期行BAEP 及SEP 测定并进行动态监测,同时行头颅CT 检查并记录GCS 评分.结果 BAEP 及SEP 预测预后的敏感性、特异性、准确性均较高.BAEP、SEP 异常程度低,则预后较好;异常程度高,则预后不良.结论 BAEP、SEP 可以比较准确地评估重型颅脑损伤患者的预后.     

Selective attention differentially affects brainstem auditory evoked potentials of electrodermal responders and nonresponders

Brainstem auditory evoked potentials (BAEPs) were recorded in adult male chronic schizophrenics on maintenance neuroleptic therapy, drug-free alcoholics, and normal subjects. Subjects were subdivided into electrodermal responders (Rs) and nonresponders (NRs). Attention was directed toward auditory or visual stimuli. Independent of diagnosis, latencies of BAEP wave V were longer in NRs when visual rather than auditory stimuli were attended to, while there was no task effect for Rs. This finding is interpreted as a sign of excessive selective filtering of auditory stimuli in NRs. In the alcoholic NRs, wave I-V conduction times were longer than those in any other subgroup, possibly indicating retarded neural transmission.     

体温过高对豚鼠耳蜗电图-脑干听觉诱发电位综合波的影响

目的：探讨体温过高对耳蜗电图-脑干听觉诱发电位综合波(ECochG-BAEP SW)的影响。方法：计算机平均叠加技术记录豚鼠脑干听觉诱发电位(BAEP)、耳蜗电图(ECochG)和：ECochG—BAEP SW，体表物理升温法逐步升高豚鼠体温，观察3组电位波形、波峰潜伏期(PL)、波峰间潜伏期(IPL)和波幅的变化。结果：随体温升高(36℃至42℃)，ECochG-BA：EPSW波形始终兼具BAEP和ECochG的特点，有十分突出的1波，其波幅为BA：EP的I波波幅的数倍，且明显大于ECochG的N1波波幅；与BAEP和ECochG一致，ECochG-BAEPSW的PL和IPL随体温升高而逐渐缩短；与BAEP的Ⅰ，Ⅱ，Ⅲ波和ECochG的N1，N2，N3波波幅相似，ECochG-BAEP SW的1，2波波幅也在体温过高至40℃后开始出现显著降低。结论：体温过高对豚鼠ECochG-BAEPSW的影响与BAEP和ECochG相似，且其波形始终兼具两者特点。     

Effects of carbamazepine and valproate on brainstem auditory evoked potentials in epileptic children

Brainstem auditory evoked potentials (BAEPs) were recorded in 18 epileptic children receiving carbamazepine and 10 epileptic children receiving valproate. BAEPs were recorded before the administration of antiepileptic drugs (AEDs) and 13 months later during which the children received AEDs. Statistical analysis of peak latencies and interpeak intervals of waves I–III–V were made. Carbamazepine treatment resulted in prolongation of peak latencies of waves I–III–V and interpeak intervals I–III and I–V. Valproate monotherapy, on the other hand, caused no consistent changes on BAEP. On the basis of these results we suggest that chronic carbamazepine therapy exerts a suppressive influence on the auditory pathways, both peripherally at the level of the cochlea and/or auditory nerve, and centrally at the brainstem.     

Characteristics of brainstem auditory evoked potentials of students studying folk dance★

BACKGROUND： Previous experiments have demonstrated that brainstem auditory evoked potential is affected by exercise, exercise duration, and frequency.
OBJECTIVE： Comparing the brainstem auditory evoked potential of students studying folk dance to students studying other subjects. DESIGN： Observational contrast study.
SETTING： Physical Education College, Shandong Normal University PARTICIPANTS： Fifty-five female students were enrolled at Shandong Normal University between September and December in 2005, including 21 students that studied folk dance and 34 students that studied other subjects. The age of the folk dance students averaged （19 ± 1） years and dance training length was （6.0 ± 1.5） years. The students that studied other subjects had never taken part in dance training or other physical training, and their age averaged （22 ± 1） years, body height averaged （162 ± 5） cm, body mass averaged （51 ± 6） kg. All subjects had no prior ear disease or history of other neurological disorders. All students provided informed consent for the experimental project.
METHODS： The neural electricity tester, NDI-200 （Shanghai Poseidon Medical Electronic Instrument Factory） was used to examine and record Brainstem Auditory Evoked Potential values of the subjects during silence, as well as to transversally analyze the Brainstem Auditory Evoked Potential values. The electrode positions were cleaned and degreased with soapy water, followed by ethanol. The selected bipolar electrodes were situated on the head： recording electrodes were placed at the Baihui acupoint, and the reference electrode was placed at the mastoid of the measured ear, with grounding electrodes in the center of the forehead. Brainstem Auditory Evoked Potential values were elicited by monaural stimulation of a ＂click＂ though an earphone; the other ear was sheltered by the white noise. The click intensity was 102 db, the stimulation frequency was 30 Hz, the bandpass filters were 1 000-3 000 Hz, the sensitivity     

Brainstem auditory evoked potentials in syndromes of decerebration,the bulbar syndrome and in central death

Summary The results are reported of serial brainstem auditory evoked potentials recordings in 51 patients with decerebration and bulbar syndrome. In contrast to the stability of latencies of single components of the potential in healthy subjects, patients with decerebration syndromes show considerable instability and an increase in the latency of all the components of the potential. In 34 decerebrate patients the P-I latency and the interpeak latencies for the medullo-pontine and ponto-mesencephalic segments as well as the central conduction time were significantly increased. There was marked reduction of the amplitude of P-V and P-III and deformation of the single components of the potential with widening and smoothing. The amplitude ratios A-V to A-I and A-III to A-I were significantly decreased. The findings are interpreted as due to mesencephalic and pontine functional disturbance during decerebration. The brainstem auditory evoked potential can be used to estimate the time of brain death. Possible causes of misinterpretation are discussed.This study was supported by Deutsche Forschungsgemeinschaft, SFB 32     

脑干听觉诱发电位在弥漫性轴索损伤中的应用

目的探讨脑干听觉诱发电位(BAEP)在弥漫性轴索损伤(DAI)的临床诊断及预后评估的价值。方法对52例DAI患者进行。BAEP反复测定,动态观察病情转化过程中BAEP各波的变化。结果①本研究中CT 对DAI的检出率为28．8％,BAEP总异常率为73．1％,经x2检验,两者差别有统计学意义。②在本研究中病例组 BAEP与对照组行t检验比较,两者差别有统计学意义。③BAEP分级与GCS、GOS的相关系数分别为-0．51022、 -0．5539,BAEP分级与GCS及GOS之间呈明显的负相关(P<0．0001)。结论BAEP可从电生理角度评价脑干的功能状态,有助于临床对脑干损伤的诊断、病情监测、疗效评估和预后判断。BAEP是评价DAI患者中脑干损伤后脑干功能和患者预后的客观指标。     

脑干听觉诱发电位在听阈正常的语言发育迟缓患儿中的意义

目的 探讨脑干听觉诱发电位（BAEP）在听阈正常而语言发育迟缓患儿中的变化规律及应用价值.方法 分析100例听阈正常而语言发育迟缓患儿BAEP的变化规律;按年龄分组比较两个年龄段之间各波的延长时间.结果 （1）BAEP正常10例,异常90例,BAEP表现为Ⅰ、Ⅴ波潜伏期（PL）延长,Ⅲ~Ⅴ、Ⅰ~Ⅴ波峰间期（IPL）延长;（2）随着年龄增长,Ⅴ波PL与Ⅲ~Ⅴ波IPL延长时间越长.结论 Ⅰ波、Ⅴ波延长对早期诊断听阈正常而语言发育迟缓患儿具有一定的意义,说明即使听阈正常也可能存在听觉传导通路异常,且随着年龄增加,脑干上段受损越严重.     

脑干听觉诱发电位改变对Binswanger病的评估价值

目的用脑干听觉诱发电位方法检测Binswanger病的脑功能改变。方法对20例BD病患者、20例非痴呆脑血管病患者、20例老年健康人同时进行脑干听觉诱发电位（BAEP）检查。结果BAEP异常：BD病10例（50％），非痴呆脑血管病2例（10％），经统计学检查BD组BAEP与健康组、非痴呆脑血管病组有显著性差异，非痴呆脑血管病组与健康组无显著性差异。结论BAEP异常反应BD病患者有脑干功能受损和弥漫性脑功能障碍，并可作为BD病患者脑功能损害检查敏感指标，以及与非痴呆脑血管病患者鉴别诊断的一个辅助检查方法。     

Middle latency auditory evoked potentials (MLAEPs) in (MS)

Middle latency auditory evoked potentials (MLAEPs) were studied in 30 definite multiple sclerosis (MS) patients in addition to brain-stem auditory evoked potentials (BAEPs). BAEP abnormalities were detected in 18 (60%) patients. MLAEPs were abnormal in 22 (73%) of them. In 15 patients BAEPs and MLAEPs were both abnormal. MLAEPs were found abnormal in 7 of the 12 patients with normal BAEPs. In 18 patients with abnormal BAEPs only 3 had normal MLAEPs. MLAEPs abnormalities are consistent with a rostral auditory pathway involvement. Therefore, they can be used in combination with BAEPs to examine the whole auditory system to improve the sensitivity.