伴神经损害脊柱侧后凸畸形患者脊髓内移后路矫形术后神经电生理变化

目的:观察伴神经功能损害脊柱侧后凸畸形患者脊髓内移后路矫形术后神经电生理变化和功能转归。方法:2005年1月~2014年1月在我院接受脊髓内移、脊柱后路矫形内固定术治疗伴神经损害的脊柱侧后凸畸形患者14例,女6例,男8例;年龄22.0±14.5岁(6~53岁)。术前均表现为双下肢麻木,其中7例伴行走不稳;双下肢病理征均为阳性。神经功能Frankel分级:C级5例,D级9例。胸弯11例,胸腰弯3例,后凸顶椎均位于侧凸顶椎区内。术前冠状面主弯Cobb角为76.9°±33.2°(65°~100°),后凸Cobb角为71.5°±31.8°(41°~125°)。采用加拿大XLTEK肌电诱发电位仪分别于术前和术后1周检测14例患者的体感诱发电位(SEP),术中行SEP和运动诱发电位(MEP)监测。在MRI上测量顶椎区凸侧脊髓外缘至椎管内缘距离,计算脊髓内移距离。结果:术前胫后神经SEP P40的波幅与峰潜伏期为1.67±0.38μV和38.96±2.51ms,术中为1.69±0.36μV和38.15±2.14ms,术中与术前比较波幅与峰潜伏期均无显著性变化(P0.05)。术后冠状面主弯Cobb角矫正率为(50.3±20.6)%(14.5%~85%),后凸Cobb角矫正率为(39.0±17.7)%(20.8%~57.9%);顶椎区脊髓位置平均内移2.3±1.6mm(0.6~4.4mm)。术后1周时胫后神经SEP P40波幅与潜伏期为2.10±0.35μV和35.54±2.12ms,与术前比较明显改善(P0.05)。神经功能均有明显改善。结论:脊髓内移后路矫形内固定治疗伴神经损害的脊柱侧后凸畸形术后患者神经电生理指标和神经功能均明显改善。     

生长棒撑开术中经颅刺激运动诱发电位和体感诱发电位监测的应用价值

目的:分析生长棒撑开术中经颅刺激运动诱发电位(MEP)和体感诱发电位(SEP)神经功能监测的应用价值。方法:回顾性分析2010年10月~2015年1月我院进行的65例141次生长棒撑开手术,在生长棒撑开术中,运用MEP和SEP进行神经功能监测。MEP监测采用经颅刺激C3、C4,记录外周肌源性MEP,SEP监测采用刺激双侧胫后神经,记录电极采用Cz-CPz。阳性诊断标准:与基线相比,MEP波幅下降75%,SEP波幅下降50%或潜伏期延长10%。结果:141例次撑开手术中成功获得具有监护价值且重复性较好MEP 139例次,检出率98.6%,全程失败2例次(占1.4%);SEP成功监测140例次,检出率99.3%,失败1例(占0.7%)。所有患者均能成功记录到一种以上的诱发电位。本组141例次手术中未出现MEP及SEP监测阳性。所有患儿术后神经系统检查均无异常发现,神经功能监测结果均为真阴性。结论:生长棒撑开术是简单安全的手术操作,但是,运用MEP和SEP进行术中神经功能监测可以为生长棒撑开术提供客观的安全评估指标。     

吸入不同浓度七氟醚复合麻醉对青少年脊柱侧弯矫形术患者体感诱发电位的影响

目的 探讨吸入不同浓度七氟醚复合麻醉对青少年脊柱侧弯矫形术患者体感诱发电位(SEP)的影响.方法 择期全麻下行脊柱侧弯矫形手术的青少年患者45例,性别不限,年龄12～17岁,体重指数15 ～ 23 kg/m2,采用随机数字表法,将其随机分为3组(n=15):低、中、高浓度七氟醚组(S1组、S2组和S3组).静脉注射芬太尼4μg/kg、咪达唑仑0.03 mg/kg、异丙酚2.0 mg/kg和罗库溴铵0.6 mg/kg麻醉诱导,气管插管后进行机械通气.静脉输注异丙酚8 mg·kg-1·h-1、瑞芬太尼0.25mg· kg-1·min -1维持麻醉.3组手术开始后分别吸入1.8％、4.0％、6.0％七氟醚10 min,记录SEP显著抑制的发生情况;分别于吸入七氟醚前和吸入七氟醚10 min时记录胫后神经SEP的P40潜伏期、P40-N50波幅、P40波形改变时间和停止七氟醚吸入后P40波形恢复时间,计算P40潜伏期延长百分比和P40-N50波幅降低百分比.结果 S1组、S2组和S3组SEP显著抑制发生率分别为80％、100％和100％(P＞0.05).与S1组比较,S2组和S3组P40潜伏期延长百分比和P40-N50波幅降低百分比升高,P40波形改变时间缩短,P40波形恢复时间延长(P＜0.05);与S2组比较,S3组P40-N50波幅降低百分比升高,P40波形改变时间缩短,P40波形恢复时间延长(P＜0.05).结论 1.8％、4.0％、6.0％七氟醚复合麻醉均可抑制青少年脊柱侧弯矫形术患者SEP,不宜用于临床上需行SEP监测的手术.     

异丙酚复合芬太尼对患者拇短展肌运动诱发电位的影响

目的 探讨异丙酚复合芬太尼对患者拇短展肌运动诱发电位(MEP)的影响.方法 择期普通外科手术患者11例,ASA Ⅰ或Ⅱ级,年龄26～48岁.以第6颈椎棘突为刺激线圈的中点进行磁刺激,周期20s.试验Ⅰ:经30 s匀速静脉注射异丙酚2mg/kg.记录给药即刻至患者出现睁眼或体动反应期间右拇短展肌MEP波幅的基础值、最低值和最后值,及其对应的潜伏期,以及波幅下降至最低值的时间(时程).试验Ⅱ:试验Ⅰ结束后30 min,经大隐静脉依次匀速注射异丙酚2 mg/kg和芬太尼5 μg/kg,每种药物注射时间为30 s.记录给药即刻开始拇短展肌MEP波幅的基础值、最低值和最后值,及其对应的潜伏期,以及时程,记录时间为360 s.结果 与基础值比较,两试验拇短展肌MEP波幅的最低值和最后值降低(P<0.01);与试验Ⅰ比较,试验Ⅱ拇短展肌MEP波幅的最后值降低(P<0.05).结论 与静脉注射异丙酚比较,异丙酚复合芬太尼对患者拇短展肌MEP的抑制作用更强.     

Chiari Ⅰ型畸形手术前后的诱发电位研究

[目的]研究Chiari Ⅰ型畸形患者手术前后的诱发电位的变化规律，观察手术前脊髓空洞的程度与诱发电位变化之间的关系。[方法]对2003年10月-2004年9月收治的15例Chiari Ⅰ型畸形患者，采取寰枕减压术、硬膜成形术。手术前第1～3d和手术后第10—14d分别检测BAEP、SEP、MEP，然后对这些患者经过6个月的随访，进行脊髓功能JOA评分和MRI复查。[结果]15例Chiari Ⅰ型畸形患者手术前14例SEP、MEP异常，手术后临床症状均有所缓解，脊髓功能JOA改善率为60．3％，MRI复查显示脊髓空洞明显缩小、诱发电位SEP检测P40-N22、N20-N13潜伏期与MEP检测中枢传导时间CMCT值和BAEP检测Ⅰ—Ⅴ峰间期，三者测的值比术前均缩短，差异有显著性。同时发现Chiari畸形患者的SEP与MEP检查测得皮层值术后比术前缩短，差异有显著性，而外周神经传导时间术后与术前比较却没有任何变化。[结论]诱发电位可以作为评价Chiari Ⅰ型畸形手术前后效果的客观而相对准确的检查方法。     

节段性血管阻断对脊髓传导功能的影响

目的 :探讨阻断节段性血管对脊髓传导功能的影响 ,分析节段性血管阻断时脊髓缺血的高危因素。方法 :对31例胸段脊柱侧凸前路凸侧开胸患者游离节段性血管 ,在距离椎间孔 2 0cm处阻断T5～T1 1的节段性血管 ,于阻断前 5min ,阻断后 2、7、1 2及 1 7min分别记录SEP ,用基本波形、P40潜伏期、P40波幅 (峰 峰 ,峰 基 )对SEP的变化进行评价。结果 :P40波幅 (峰 峰 )在阻断 2min时显著降低 ,平均下降 0 64μV(2 6 1 2 % ) ,而P40潜伏期在 2min及7min显著延长 ,分别延长 1 2 2ms(3 39% )和 0 81ms(2 76 % )。SEP波形在血管阻断后 2、7、1 2及 1 7min时无明显变化 ,均为Ⅲ级或Ⅳ级。结论 :脊柱侧凸前路手术中 ,对于无血管畸形的患者 ,阻断单侧多根节段性血管可暂时影响脊髓传导功能 ,主要发生在阻断后前 7min内 ,此后脊髓传导功能恢复正常 ,并不导致临床上脊髓缺血性功能损害。     

右美托咪啶-异丙酚-芬太尼复合麻醉对颈椎手术病人体感诱发电位及运动诱发电位的影响

目的 评价右美托咪啶-异丙酚-芬太尼复合麻醉对颈椎手术病人体感诱发电位及运动诱发电位的影响.方法 择期全麻下行颈椎手术的病人36例,随机分为2组(n=18):异丙酚-芬太尼复合麻醉组(C组)和右美托咪啶-异丙酚-芬太尼复合麻醉组(D组).麻醉诱导:TCI异丙酚,血浆靶浓度为2μg/ml,静脉注射芬太尼1～2μg/kg,意识消失后经口置入喉罩进行通气.意识消失后D组经10 min静脉注射右美托咪啶0.5μg/kg,随后以0.5μg·kg-1·h-1的速率静脉输注至术毕,C组给予等容量生理盐水.分别于给予右美托咪啶前及静脉输注右美托咪啶10 min时记录体感诱发电位P15-N20波的波幅和潜伏期,并记录运动诱发电位的未引出情况.结果 与C组比较,D组P15-N20波的波幅和潜伏期差异无统计学意义(P＞0.05);两组运动诱发电位未引出率均为0.结论 右美托咪啶-异丙酚-芬太尼复合麻醉对颈椎手术病人体感诱发电位及运动诱发电位无影响.     

脊髓髓外冲击负荷后脊髓血流与诱发电位变化的相关研究

[目的] 研究脊髓髓外冲击负荷对脊髓血流及诱发电位的影响,探讨脊髓损伤后脊髓血流与诱发电位变化的规律,以及它们之间的相关性.[方法] 选用雄性SD大鼠120只,随机分为4组,每组30只,A组为假手术组,B、C、D为实验组,在大鼠T10椎板处分别给予10、15、20 N的椎板外冲击负荷.术后0 min,1、6 h,1、6、12、24 d时间点测量冲击负荷位置的脊髓白质、灰质血流以及SEP、MEP测量,进行相关性分析.[结果] 脊髓内灰质白质的血流表现出随冲击负荷的增加而减小的趋势.A组脊髓血流及SEP、MEP无明显变化,B组脊髓血流及SEP、MEP出现一过性降低然后恢复正常,两组之间无明显差异.C、D组脊髓血流及SEP、MEP均表现为持续下降后再缓慢的回升的规律性变化,其中C组在24 d恢复正常,D组在24 d时仍然低于正常,经统计学分析脊髓血流与诱发电位具有明显的相关性.[结论] 椎板外冲击负荷通过改变脊髓血流来影响脊髓的功能,并且脊髓血流和诱发电位有明显的相关性.     

SEP与MEP对脊髓功能的监测作用

随着影像学技术的快速发展,磁共振成像可准确提供更多的信息,直接评价脊髓损伤范围和程度,从而提高了脊髓型颈椎病(CSM)确诊率。但颈椎退变引起脊髓受压并不一定伴随脊髓病变,且大部分MRI显示椎管狭窄的患者既无脊髓损伤的临床症状也无电生理的改变[1]。王新家等[2]发现脊髓电生理特性的改变与病理变化以及功能变化相一致;并发现躯体感觉诱发电位(SEP)与运动诱发电位(MEP)的潜伏期与椎管侵占率、CBS功能评分呈正相关。Maertens等[3]发现MEP与SEP在脊髓型颈椎病的异常率分别为93%和73%。因此MEP与SEP是比影像学诊断和临床检查脊…     

不同意识状态对脑电双频指数和听觉诱发电位指数与异丙酚效应室浓度关系的影响

目的观察不同意识状态对脑电双频指数（BIS）和听觉诱发电位指数（AEPI）与异丙酚效应室浓度关系的影响。方法择期行腹腔镜胆囊手术病人20例，ASAⅠ或Ⅱ级，靶控输注异丙酚麻醉诱导，初始效应室靶浓度1．0μg／ml，以1．0μg／ml递增，至5μg／ml时，静脉注射罗库溴铵0．06mg／kg行气管插管，气管插管后以效应室靶浓度3μg／ml维持麻醉，切皮前调为6μg／ml。术中维持血液动力学平稳，术毕停止靶控输注异丙酚。记录麻醉诱导期和苏醒期效应室靶浓度平衡后BIS、AEPI；意识消失前1min、后1min、睁眼前1min、后1min时BIS和AEPI。结果麻醉诱导期BIS和AEPI与异丙酚效应室浓度均呈负相关，意识消失前BIS和AEPI与异丙酚效应室浓度呈负相关；意识消失后BIS与异丙酚效应室靶浓度呈负相关。异丙酚效应室浓度0、1、2μg／ml比较，异丙酚效应室浓度3、4、5、6μg／ml时AEPI降低，随着异丙酚效应室浓度的升高BIS逐渐下降（P〈0．05），睁眼后1min AEPI高于睁眼前1min（P〈0．05）。结论BIS与异丙酚效应室浓度的相关性不受意识状态的影响，AEPI监测无意识状态到意识恢复的变化比BIS灵敏。     

TMS—MEP与CSEP诊断脊髓损伤的作用比较

目的比较脊髓损伤后经颅磁刺激运动诱发电位和皮层体感诱发电位检测的诊断价值。方法 １５只家猫脊髓部分切断和６９例ＳＣＩ的ＭＥＰ和ＣＳＥＰ检测。结果 ＭＥＰ对脊髓前柱损伤，前后柱混合损伤和肌力异常极敏感，对后柱损伤不敏感；而ＣＳＥＰ对脊髓后柱损伤，前后柱混合损伤和关节位置觉异常十分敏感，对前柱伤却相反。     

Usefulness and Pitfalls of Intraoperative Spinal Motor Evoked Potential Recording by Direct Cortical Electrical Stimulation

Summary ? Objective. The aim of this study is to investigate the usefulness and problems with spinal motor evoked potential (MEP) recording, especially the reasons for failed recording. We report our personal experience over the last 8 years in patients with lesions adjacent to the primary motor cortex. Methods. MEP records of 50 consecutive patients were retrospectively reviewed. MEP was recorded by a catheter electrode inserted in the cervical epidural space. Stimulation electrodes were placed on the cortical surface during surgery. SEP recording was also performed in 29 of 50 patients. Results. MEP was obtained in 40 cases, and SEP was recorded in all 29 cases. The central sulcus was identified in 93% of patients in whom both MEP and SEP were performed, whereas in only 86% of patients who underwent only MEP. The main reason for MEP failure were inadequate exposure of the motor cortex, pre-existing hemiparesis and technical errors. Postoperative deterioration of motor function was closely related to intra-operative MEP changes. Conclusion. MEP is a useful tool to determine the motor cortex and to predict postoperative motor function. However, precise pre-operative craniotomy planning and combination with intra-operative SEP is essential to reduce the MEP failure.     

体感诱发电位联合运动诱发电位监测在颈动脉内膜剥脱术中的应用

目的评估在颈动脉内膜剥脱术中(carotid endarterectomy,CEA)中采用体感诱发电位(somatosensory evoked potential,SSEP)与运动诱发电位(motor evoked potential,MEP)联合监测的方案对于预防术中脑缺血发生的准确性。方法选择因颈动脉狭窄择期拟行CEA患者90例,男71例,女19例,年龄18~80岁,ASAⅡ或Ⅲ级。术中监测SSEP和MEP,记录颈内动脉阻断前、颈动脉阻断时、阻断期间及开放后直至术毕SSEP和MEP波幅和潜伏期。评估术后5d内神经功能缺失情况,以发生神经功能缺失作为评判术中脑缺血发生的金标准。结果本研究中14例(15.6%)患者发生术后神经功能缺失。SSEP预测脑缺血发生的灵敏度79%、特异度92%;MEP预测脑缺血发生的灵敏度86%、特异度89%、SSEP+MEP联合监测的灵敏度为79%、特异度99%。结论在颈动脉内膜剥脱术中,体感诱发电位预测脑缺血发生的特异度高,运动诱发电位灵敏度高;二者联合监测可提高监测的特异性,弥补单一监测的不足。     

Somatosensory and Motor Evoked Potentials in Patients with Tumours in the Spinal Canal

Summary  Motor and sensory evoked potentials were recorded in 27 patients with expanding spinal tumour. The patients were divided into 2 groups: I. tumours at the level of the spinal cord [18] and II. at the level of the cauda equina [9]. On the basis of the localization of the tumour, midline and lateral subgroups were distinguished.  The latencies of motor evoked potentials were prolonged in most of the patients, even those without paresis, in both groups. The motor evoked potentials detected subclinical motor lesions in 7 patients. All patients but one manifested sensory deficits, which could not be shown with the somatosensory evoked potentials.  Significantly more prolonged cortical motor latencies were found in most of the patients with a laterally located tumour on the tumour side than contralaterally, whereas in somatosensory evoked potentials this difference was not apparent.  On the basis of these observations, we concluded that motor evoked potentials, 1. could more reliably detect the neural deficit than somatosensory evoked potentials; 2. could show the side where the tumour was located; 3. proved useful in the detection of subclinical motor lesions. The general conclusion may be drawn that this electrophysiological method can provide useful information for the surgeon.     

普鲁卡因对上肢短潜伏期体感诱发电位的影响

目的：探讨静滴普鲁卡因对短潜伏期体感诱发电位（ＳＬＳＥＰ）的影响。方法;对上肢感觉传导无异常的病人１５例,分别观察静脉滴注普鲁卡因前以及滴注１％普鲁卡因２０ｍｇ．ｋｇ＾０－１．ｈ＾－１１０分钟、４０ｍｇ．ｋｇ＾－１、ｈ．＾－１５分钟和６０ｍｇ．ｋｇ＾－１．ｈ＾－１５分钟的上肢ＳＬＳＥＰ,比较Ｎ１４,Ｎ２０,Ｐ２３各波的潜伏期,Ｎ１４－Ｎ２０波间潜伏期（ＣＣＴ）以及Ｎ２０Ｐ－Ｐ２０的峰间值。结果：Ｓ     

A study of motor and sensory evoked potentials in chronic cauda equina compression of the dog

Previous experimental studies have shown the effects of acute compression of the spinal cord and peripheral nerve roots. Recently, however, a few studies of chronic compression of the cauda equina in animal models have been reported. The purpose of this study was to determine the long-term electrophysiologic changes resulting from chronic compression of the cauda equina in dogs. An animal model of lumbar spinal stenosis was prepared according to Delamarter's method. Four experimental groups, each containing six dogs, were studied. One group underwent only laminectomy of the sixth and seventh lumbar vertbrae; these animals served as controls. In the three other groups, a laminectomy was performed and the cauda equina was constricted by 25%, 50%, and 75%, respectively, to produce chronic compression. Weekly neurologic examinations were carried out, and the neurologic deficits were graded using a modified Tarlov system. Sensory, and motor evoked potentials were recorded preoperatively, immediately after constriction, and at 2 weeks and 1, 2, and 3 months postoperatively. The animals in the control group showed no changes in sensory or motor evoked potentials. The dogs in which the cauda equina had been constricted by 25% showed no neurologic deficits and only mild changes in sensory and motor evoked potentials. The dogs in which the cauda equina had been constricted by 50% showed mild initial motor weakness, and major changes in the evoked potentials. The dogs in which the cauda equina had been constricted by 75% showed significant weakness, paralysis of the tail, and urinary incontinence; all dogs were partially recovered by the 3rd month, but all still showed neurogenic changes in the evoked potentials. Sensory and motor evoked potentials revealed neurologic abnormalities before the appearance of neurologic signs and symptoms. Constriction of more than 50% was the critical point that resulted in complete loss or reduction of the evoked potentials and in neurologic deficits. Dogs in which motor and sensory evoked potentials recovered also showed gradual disappearance of neurologic symptoms and signs. Recovery of motor evoked potentials in particular was associated with complete disappearance of neurologic symptoms and signs. For accurate prognosis in cases of chronic cauda equina compression, a combined diagnostic study of sensory and motor evoked potentials is recommended.     

Auditory evoked potential index: a quantitative measure of changes in auditory evoked potentials during general anaesthesia

We describe a novel index derived from the auditory evoked potential, the auditory evoked potential index, and we compare it with latencies and amplitudes related to clinical signs of consciousness and unconsciousness. Eleven patients, scheduled for total knee replacement under spinal anaesthesia, completed the study. The initial mean (SD) value of the auditory evoked potential index was 72.5 (11.2). During the first period of unconsciousness it decreased to 39.6 (6.9) and returned to 66.8 (12.5) when patients regained consciousness. Thereafter, similar values were obtained whenever patients lost and regained consciousness. Latencies and amplitudes changed in a similar fashion. From all parameters studied, Na latencies had the greatest overlap between successive awake and asleep states. The auditory evoked potential index and Nb latencies had no overlap. The consistent changes demonstrated suggest that the auditory evoked potential index could be used as a reliable indicator of potential awareness during propofol anaesthesia instead of latencies and amplitudes.     

Comparison of Single and Dual Monitoring during Carotid Endarterectomy

We compared the rate of selective shunt and pattern of monitoring change between single and dual monitoring in patients undergoing carotid endarterectomy (CEA). A total of 121 patients underwent 128 consecutive CEA procedures. Excluding five procedures using internal shunts in a premeditated manner, we classified patients according to the monitoring: Group A (n = 72), patients with single somatosensory evoked potential (SSEP) monitoring; and Group B (n = 51), patients with dual SSEP and motor evoked potential (MEP). Among the 123 CEAs, an internal shunt was inserted in 12 procedures (9.8%) due to significant changes in monitoring (Group A 5.6%, Group B 15.7%, p = 0.07). The rate of shunt use was significantly higher in patients with the absence of contralateral proximal anterior cerebral artery (A1) on magnetic resonance angiography (MRA) than in patients with other types of MRA (p <0.001). Significant monitor changes were seen in 16 (12.5%) in both groups. In four of nine patients in Group B, SSEP and MEP changes were synchronized, and in the remaining five patients, a time lag was evident between SSEP and MEP changes. In conclusion, the rate of internal shunt use tended to be more frequent in patients with dual monitoring than in patients with single SSEP monitoring, but the difference was not significant. Contralateral A1 absence may predict the need for a shunt and care should be taken to monitor changes throughout the entire CEA procedure. Use of dual monitoring can capture ischemic changes due to the complementary relationship, and may reduce the rate of false-negative monitor changes during CEA.