A comparative study of brain-stem auditory evoked potentials and blink reflexes in posterior fossa tumor patients

Brain-stem auditory evoked potentials (BAEP's) and blink reflexes (BR's) were recorded from 40 patients with clinical and radiological evidence of posterior fossa tumors. They were examined in three groups according to the anatomical location of the lesion: Group A included 15 patients with midline tumors; Group B included 14 patients with cerebellar hemispheric tumors; and Group C included 11 patients with cerebellopontine angle (CPA) tumors. More of the 40 patients had BAEP abnormalities (32) than BR abnormalities (24). All of the 11 patients with CPA tumors had some kind of BAEP and BR abnormalities. The 14 patients with cerebellar tumors showed the next most frequent abnormalities: 12 related to the BAEP's and seven to the BR's. The 15 patients with midline tumors showed the least number of abnormalities: nine related to BAEP's and six to the BR's. In the analysis of BAEP wave latencies and interpeak latencies, a wave III latency delay occurred in all groups; latencies of waves IV and V were more significantly delayed in patients with CPA and cerebellar hemispheric tumors, and the interpeak latencies of waves III-V and I-V were markedly prolonged only in patients with CPA tumors (p less than 0.01). In all tumor groups, early response (R1) of BR's was significantly delayed in comparison to a healthy volunteer control group (p less than 0.01), but R1 was more pronounced in cases of CPA tumors when compared with the other tumor groups. Although significant delays in direct and consensual late reflex components (R2) of BR's were noted in comparison to the control group, this delay could not differentiate one tumor group from another. In can be concluded that, while these tests reflect the functions of different cranial nerves and brain-stem tracts, BAEP monitoring is more sensitive than BR testing for the detection of brain-stem involvement in posterior fossa tumors. Cerebellopontine angle tumors almost always cause severe abnormalities in both tests. Cerebellar hemispheric tumors and midline tumors cause fewer changes in both BAEP's and BR's.     

The blink reflex before and after percutaneous glycerol rhizotomy in patients with trigeminal neuralgia — a prospective study of 28 patients

Summary The blink reflex was prospectively studied in 28 patients with trigeminal neuralgia, prior-to and following percutaneous glycerol rhizotomy to the Gasserian ganglion. Fifteen patients (54%) had varying degrees of sensory loss in the trigeminal nerve distribution already before glycerol injection. Three more patients developed sensory loss following glycerol injection. Thus following glycerol injection 18 patients had graded sensory loss.Pre-injection the blink reflex showed abnormal R1 wave in 57% patients, while direct and consensual R2 waves were abnormal in 43% and 48%, respectively. Post-injection R1 wave was abnormal in 64% patients. Direct R2 waves were abnormal in 33% patients. Thus clinical findings of sensory loss correlated well with pre- and post-injection blink reflex abnormality.Postoperatively R1 and ipsilateral R2 latencies from the side of the injection deteriorated and consensual R2 latency improved, thus, signifying better function on the contralateral side following reflief of pain by glycerol rhizotomy.     

Electromyographic assessment of blink reflexes correlates with a clinical scale of depth of sedation/anaesthesia and BIS during propofol administration

BACKGROUND: General anaesthesia is characterized by loss of consciousness, amnesia and obtundation of reflex responses to noxious stimuli. Quantifying the blink reflex may reflect the depression of reflex arches induced by anaesthetics and thus being informative on the anaesthetic state. METHODS: The relation between the electrically evoked blink reflexes and the depth of sedation and anaesthesia induced with intravenous propofol was investigated. Twenty patients received propofol by target-controlled infusion to create a stepwise deepening of sedation and anaesthesia. Depth of anaesthesia was assessed using the observer's assessment of anaesthesia and sedation (OAAS) scale, and by bispectral EEG analysis (BIS). Probit analysis was used to estimate the predicted propofol effect site concentrations producing unconsciousness, no response to noxious stimulation, and loss of blink reflex components. RESULTS: Latency of the first (R1) and second (R2) blink component increased, whereas duration and area decreased with increasing depth of sedation and anaesthesia. A reasonably strong correlation between OAAS and the areas of R1 and R2 components was found (Spearman's rho = 0.92 and 0.89). The areas of R1 and R2 and the OAAS also correlated with BIS (Spearman's rho = 0.91, 0.88 and 0.90). EC(50) and EC(95) for loss of R1 were 2.8 (95% CI: 2.5-3.2) micro g/ml and 4.6 (95% CI: 4.1-5.5) micro g/ml, respectively. CONCLUSIONS: Our results suggest that the differential sensitivity of the components of the blink reflex could be useful in monitoring depth of sedation and light levels of anaesthesia during the administration of propofol. Both OAAS and BIS correlate similarly with the blink reflex components.     

Brainstem auditory evoked potential combined with high resolution cranial base CT can optimize the diagnosis of auditory nerve injury

PurposeAuditory nerve injury is one of the most common nerve injury complications of skull base fractures. However, there is currently a lack of auxiliary examination methods for its direct diagnosis. The purpose of this study was to find a more efficient and accurate means of diagnosis for auditory nerve injury.MethodsThrough retrospectively analyzing the results of brainstem auditory evoked potential (BAEP) and high-resolution CT (HRCT) in 37 patients with hearing impairment following trauma from January 1, 2018 to July 31, 2020, the role of the two inspection methods in the diagnosis of auditory nerve injury was studied. Inclusion criteria were patient had a clear history of trauma and unilateral hearing impairment after trauma; while exclusion criteria were: (1) severe patient with a Glasgow coma scale score ≤5 because these patients were classified as severe head injury and admitted to the intensive care unit, (2) patient in the subacute stage admitted 72 h after trauma, and (3) patient with prior hearing impairment before trauma. According to Goodman's classification of hearing impairment, the patients were divided into low/medium/severe injury groups. In addition, patients were divided into HRCT-positive and negative groups for further investigation with their BAEP results. The positive rates of BEAP for each group were observed, and the results were analyzed by Chi-square test (p < 0.05, regarded as statistical difference).ResultsA total of 37 patients were included, including 21 males and 16 females. All of them were hospitalized patients with GCS score of 6–15 at the time of admission. The BAEP positive rate in the medium and severe injury group was 100%, which was significantly higher than that in the low injury group (27.27%) (p < 0.01). The rate of BEAP positivity was significantly higher in the HRCT-positive group (20/30, 66.7%) than in the HRCT-negative group (1/7, 14.3%) (p < 0.05). Twenty patients (54.05%) were both positive for BEAP and HRCT test, and considered to have auditory nerve damage. Six patients (16.22%) were both negative for BEAP and HRCT test, and 10 patients (27.03%) were BAEP-negative but HRCT-positive: all the 16 patients were considered as non-neurological injury. The rest 1 case (2.70%) was BAEP-positive but HRCT-negative, which we speculate may have auditory nerve concussion.ConclusionBy way of BAEP combining with skull base HRCT, we may improve the accuracy of the diagnosis of auditory nerve injury. Such a diagnostic strategy may be beneficial to guiding treatment plans and evaluating prognosis.     

Brainstem auditory evoked response and vestibulo-ocular reflex in severe head injury patients

Summary During follow-up of 485 adult patients with mainly mild head injury 27% of the patients were unemployed after an observation period of 3–5 years (mean 4.0 years). The length of sick leave during the last 3 years was longer than for a control group. Reduced physical capacity and time of sick leave during the last 3 years were the variables which were most closely associated with unemployment at follow-up. The long term family life, contact with friends and income were less favourable in the head injured patients than in the control group.     

桥小脑角区肿瘤的显微外科手术治疗及预后分析

目的 探讨桥小脑角区肿瘤的显微外科手术治疗方式、方法及预后分析.方法 回顾性分析65例桥小脑角区肿瘤显微外科手术方式、方法及预后.结果 本组肿瘤全切除58例,面神经解剖保留51例,随访1～3 a,面瘫恢复30例,部分恢复8例,无肿瘤复发.结论 娴熟的显微镜下手术技巧及熟熟练掌握相关解剖知识,在切除肿瘤的同时,能最大限度...     

Measurements of brain-stem auditory evoked potentials in patients with spontaneous intracerebral hemorrhage

Brain-stem auditory evoked potentials (BAEP's) were recorded in 19 patients with spontaneous intracerebral hemorrhage. More than half of the patients were deeply comatose. There was no correlation between BAEP changes and different types of spontaneous intracerebral hemorrhage or between BAEP's and coma grading by the Glasgow Coma Scale. However, BAEP's were a significant prognostic aid in these cases and useful in indicating the level of the brain-stem lesion.     

脑外伤后综合征患者脑电图和脑干听觉诱发电位异常分析

目的探讨脑外伤后综合征（PTBS）的脑电图（EEG）、脑干听觉诱发电位（BAEP）特点。方法对本院2005年9月至2010年10月门诊及住院就诊的659例患者诊断为PTBS行EEG和BAEP检查,并与662名健康志愿者的EEG、BAEP作对照分析。结果 PTBS病患EEG轻度异常533例（80.9%）,中度异常6例（0.9%）,重度异常0例（0%）。与正常组比,有显著差异（P〈0.01）。PTBS病患检测BAEP结果显示,BAEPI波潜伏期与对照组相比差异无显著意义（P〉0.05）。BAEP其他波潜伏期及峰间期均延长,与对照组有显著差异（P〈0.001）。EEG异常越重,BAEP异常率越高,BAEP异常也越明显。结论 EEG与BAEP联合应用,可以评估脑外伤患者的预后。     

A three-dimensional and volume determination of tumors of the cerebellopontine angle

We propose a new technique to accurately determine the volume of cerebellopontine angle (CPA) tumors. It has been determined that the measurement of the long axis in a slice plane of the CPA tumor does not adequately measure the total growth of the tumor. Volume measurements are more accurate indicators of the mass of the tumor.     

Improvement in brainstem auditory evoked potentials after suboccipital decompression in patients with chiari I malformations

OBJECT: The optimal treatment for patients with symptoms related to Chiari I malformation remains controversial. Although a suboccipital decompression with duraplasty is most commonly performed, there may be a subset of patients who improve in response to bone decompression alone. In an initial attempt to identify such patients, we performed a continuous study of intraoperative brainstem auditory evoked potentials (BAEPs) in patients undergoing a standard decompression with duraplasty and compared conduction times at three different time points: 1) baseline while the patient is supine (before positioning); 2) immediately after opening of the bone and release of the atlantooccipital membrane (that is, the dural band); and 3) after opening of the dura mater. METHODS: Eleven children and young adults (mean age 9.8 years) with symptoms related to Chiari I malformation underwent suboccipital decompression and duraplasty with intraoperative monitoring of BAEPs and somatosensory evoked potentials (SSEPs). Six patients (55%) had associated syringomyelia. At baseline, the I to V interpeak latency (IPL) for both sides (total 21 BAEPs) was 4.19 +/- 0.22 msec (mean +/- standard deviation). After complete bone decompression and before the dura mater was opened, the I to V IPL decreased to 4.03 +/- 0.25 msec (p = 0.0005). When the dura was opened, however, no further decrease in the I to V IPL was detected (4.03 +/- 0.25 msec; p = 0.6). The SSEPs remained stable throughout the procedure. CONCLUSIONS: In children and young adults undergoing suboccipital decompression with duraplasty for Chiari I malformation, the vast majority of improvement in conduction through the brainstem occurs after bone decompressionand division of the atlantooccipital membrane, rather than after opening of the dura. Additional studies are needed to establish whether the improvement seen with BAEP monitoring during bone decompression will predict long-term clinical improvement in these patients.     

小骨窗显微手术切除大型桥小脑角肿瘤及神经功能保护

目的探讨大型（直径≥3cm）桥小脑角肿瘤的小骨窗显微手术切除方法及神经功能保护。方法回顾性分析经乙状窦后入路小骨窗显微手术切除的32例大型桥小脑角肿瘤患者的临床资料,肿瘤全切除28例（87．5％）,次全切除4例（12．5％）。结果本组无手术死亡病例。面神经解剖保留率为93．8％（30／32）,面神经功能（House—BrackmannI、Ⅱ级）保留率为78．1％（25／32）,听神经解剖保留率为87．5％（28／32）,听力保留率68．8％（22／32）。结论采用乙状窦后入路小骨窗显微手术切除大型桥小脑角肿瘤是一种安全、有效的手术方法,在保留神经功能完整性的前提下应尽量切除肿瘤。     

阴茎勃起障碍病人神经诱发电位146例临床分析

本文对１４６例阴茎勃起障碍病人的阴部神经诱发电位（ＰｕｄｅｎｄａｌＥＰｓ）进行了检测分析，其中骨盆骨折３１例，腰椎骨折１１例，盆腔手术９例，高血压１６例，糖尿病１７例，严重手淫６２例。分析结果：阴部皮层体感神经诱发电位（ＣＰＥＰ）、骶髓反射时（ＳＲＬ）和生殖皮层运动诱发电位（ＣＭＥＰ）总体异常率在骨盆骨折、腰椎损伤、盆腔手术、高血压、糖尿病及严重手淫组分别为５１．６１％、５４．５５％、７７．７７％、３１．２５％、４７．０５和３２．２６％，超强度电流刺激在骨盆骨折、腰椎损伤、盆腔手术、高血压、糖尿病及严重手淫组依次为５５．５５％、４５．５４％、４１．１７％、３８．７０％、３０．６０％和６．２５％。研究结果表明：在骨盆骨折、腰椎损伤、盆腔手术及糖尿病人，其ＰｕｄｅｎｄａｌＥＰｓ异常率及超强度刺激率都相当高。提示在这些病人中阴部神经受损的机率较高，而ＰｕｄｅｎｄａｌＥＰｓ检测将有助于阴茎勃起障碍的病因学诊断     

Neuropsychological findings in patients with intraventricular tumors

BACKGROUND: Intraventricular tumors are quite rare and become symptomatic with hydrocephalus-related signs such as headache, double vision, and seizures. Also, most of the patients show neuropsychological deficits, especially memory problems and lack of attention. METHODS: We reviewed the charts and computed tomographic/magnetic resonance images of 15 patients with tumors of the lateral and third ventricle, who were also examined by a neuropsychologist pre- and postoperatively. Neuropsychological testing included tests of attention, memory, executive functions, and concentration. RESULTS: Between 1995 and 2003, 7 patients with colloid cysts of the third ventricle (3 men, 4 women; mean age, 38 years), 5 patients with meningiomas of the lateral ventricle (2 men, 3 women; mean age, 51 years), and 3 patients with astrocytomas and ependymoma (2 men, 1 woman; mean age, 38 years) were treated. All patients with colloid cysts and meningiomas showed mental changes, especially attention and memory deficits. Symptoms improved markedly after surgical intervention. The 3 patients with astrocytoma and ependymoma showed normal results pre- and postoperatively. CONCLUSION: Neuropsychological testing is very useful in patients with intraventricular lesions and important for follow-up examinations. It should be included in every workup examination in this small patient group.     

青少年特发性脊柱侧凸患者体感诱发电位的特点及与Cobb角的关系

Objective To investigate the abnormality of somatosensory evoked potentials (SEPs) in adolescent idiopathic scoliosis (AIS) with different curve magnitudes, and to explore its effect on the etiopathogenesis of AIS. Methods Posterior tibial nerve SEPs were evaluated on 489 young operative treated AIS patients with a Cobb angle > 40°and 45 age-matched healthy control individuals. Absence of SEPs waveforms, prolongation of peek latency or asymmetrical peek latency were defined as pathological change. Base on the control reference, the incidence of pathological SEPs was determined in AIS group. The association of abnormal SEPs and curve severity for MS patients was also assessed. Results Peek latency corrected for body height was slightly longer in AIS patients than in controls, however, with no significant difference. Interside difference of latency was significantly larger in AIS patients. Abnormal SEPs were found in 166 of 489 AIS patients. Among these, 17 (10.2%) showed absent waveforms, 50 (30.1%) had unilateral latency prolongation, 38 (22.9%) had bilateral latency prolongation, and 120 (72.3%) showed significant interside difference. Statistical analysis failed to show a correlation between abnormal SEPs and the curve severity of spinal deformity. Conclusion Disorder of somatosensory pathways does exist in a subgroup of AIS patients, and it might be a primary factor other than secondary change, and could play an import role in the etiopathogenesis of AIS.     

青少年特发性脊柱侧凸患者体感诱发电位的特点及与Cobb角的关系

目的 分析不同Cobb角青少年特发性脊柱侧凸(AIS)体感诱发电位(SEP)的异常模式,探讨其在AIS发病机制中的作用.方法 回顾性分析2001年9月至2007年9月治疗的489例AIS患者(AIS组)的术前SEP的峰潜伏期及左、右侧峰潜伏期差值,并与45例年龄匹配的健康青少年(对照组)的SEP相比较.SEP波形消失、峰潜伏期延长及峰潜伏期不对称定义为SEP异常的标准.计算AIS组SEP异常发生率,并分析SEP异常与侧凸严重程度的相关性.结果 AIS组峰潜伏期(身高校正)较对照组略高,但无统计学意义.AIS组左右侧峰潜伏期差值显著高于对照组.489例AIS中SEP异常者共有166例,其中波形单侧或双侧消失17例(10.2%),单侧潜伏期延长50例(30.1%),两侧均延长38例(22.9%),两侧不对称120例(72.3%).根据不同侧凸严重程度分组分析,结果提示SEP异常与侧凸严重程度无关.结论 部分AIS患者存在体感传导通路异常,其可能为AIS的原发性因素,可能在AIS的发病机制中起着重要的作用.     

青少年特发性脊柱侧凸患者体感诱发电位的特点及与Cobb角的关系

Objective To investigate the abnormality of somatosensory evoked potentials (SEPs) in adolescent idiopathic scoliosis (AIS) with different curve magnitudes, and to explore its effect on the etiopathogenesis of AIS. Methods Posterior tibial nerve SEPs were evaluated on 489 young operative treated AIS patients with a Cobb angle > 40°and 45 age-matched healthy control individuals. Absence of SEPs waveforms, prolongation of peek latency or asymmetrical peek latency were defined as pathological change. Base on the control reference, the incidence of pathological SEPs was determined in AIS group. The association of abnormal SEPs and curve severity for MS patients was also assessed. Results Peek latency corrected for body height was slightly longer in AIS patients than in controls, however, with no significant difference. Interside difference of latency was significantly larger in AIS patients. Abnormal SEPs were found in 166 of 489 AIS patients. Among these, 17 (10.2%) showed absent waveforms, 50 (30.1%) had unilateral latency prolongation, 38 (22.9%) had bilateral latency prolongation, and 120 (72.3%) showed significant interside difference. Statistical analysis failed to show a correlation between abnormal SEPs and the curve severity of spinal deformity. Conclusion Disorder of somatosensory pathways does exist in a subgroup of AIS patients, and it might be a primary factor other than secondary change, and could play an import role in the etiopathogenesis of AIS.     

青少年特发性脊柱侧凸患者体感诱发电位的特点及与Cobb角的关系

Objective To investigate the abnormality of somatosensory evoked potentials (SEPs) in adolescent idiopathic scoliosis (AIS) with different curve magnitudes, and to explore its effect on the etiopathogenesis of AIS. Methods Posterior tibial nerve SEPs were evaluated on 489 young operative treated AIS patients with a Cobb angle > 40°and 45 age-matched healthy control individuals. Absence of SEPs waveforms, prolongation of peek latency or asymmetrical peek latency were defined as pathological change. Base on the control reference, the incidence of pathological SEPs was determined in AIS group. The association of abnormal SEPs and curve severity for MS patients was also assessed. Results Peek latency corrected for body height was slightly longer in AIS patients than in controls, however, with no significant difference. Interside difference of latency was significantly larger in AIS patients. Abnormal SEPs were found in 166 of 489 AIS patients. Among these, 17 (10.2%) showed absent waveforms, 50 (30.1%) had unilateral latency prolongation, 38 (22.9%) had bilateral latency prolongation, and 120 (72.3%) showed significant interside difference. Statistical analysis failed to show a correlation between abnormal SEPs and the curve severity of spinal deformity. Conclusion Disorder of somatosensory pathways does exist in a subgroup of AIS patients, and it might be a primary factor other than secondary change, and could play an import role in the etiopathogenesis of AIS.     

青少年特发性脊柱侧凸患者体感诱发电位的特点及与Cobb角的关系

Objective To investigate the abnormality of somatosensory evoked potentials (SEPs) in adolescent idiopathic scoliosis (AIS) with different curve magnitudes, and to explore its effect on the etiopathogenesis of AIS. Methods Posterior tibial nerve SEPs were evaluated on 489 young operative treated AIS patients with a Cobb angle > 40°and 45 age-matched healthy control individuals. Absence of SEPs waveforms, prolongation of peek latency or asymmetrical peek latency were defined as pathological change. Base on the control reference, the incidence of pathological SEPs was determined in AIS group. The association of abnormal SEPs and curve severity for MS patients was also assessed. Results Peek latency corrected for body height was slightly longer in AIS patients than in controls, however, with no significant difference. Interside difference of latency was significantly larger in AIS patients. Abnormal SEPs were found in 166 of 489 AIS patients. Among these, 17 (10.2%) showed absent waveforms, 50 (30.1%) had unilateral latency prolongation, 38 (22.9%) had bilateral latency prolongation, and 120 (72.3%) showed significant interside difference. Statistical analysis failed to show a correlation between abnormal SEPs and the curve severity of spinal deformity. Conclusion Disorder of somatosensory pathways does exist in a subgroup of AIS patients, and it might be a primary factor other than secondary change, and could play an import role in the etiopathogenesis of AIS.