神经电生理定量评价大鼠脊髓损伤

[目的]评价神经电生理监测在大鼠脊髓损伤(SCI)中的意义。[方法] 50只雌性健康SD大鼠随机分成5组,每组10只。分别为假手术组,Allen's打击制备SCI 40 g·cm组、60 g·cm组、80 g·cm组和100 g·cm组。监测体感诱发电位(SEP)和经颅电刺激运动诱发电位(MEP);同时进行大鼠运动功能评分(BBB)。[结果]随损伤程度的增加,SEP和MEP潜伏期显著延长、波幅减小。损伤后各时间点,不同组别间潜伏期和波幅的差异均有统计学意义(P0.05);100 g·cm损伤后SEP和MEP波消失。随着打击程度的加重,BBB评分明显下降(P0.05)。损伤程度分组与评价指标均有显著相关性(P0.05),Spearman秩相关的R值依次为MEP潜伏期、MEP波幅、BBB评分、SEP潜伏期、SEP波幅。[结论]通过神经电生理监测指标,特别是MEP,可以准确客观地判断SCI的严重程度。     

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…     

体感诱发电位在颈椎病前后路联合手术中的监护作用

目的分析皮层体感诱发电位（somatosensory evoked potential,SEP）在颈椎病前后路联合手术中的监护及判断颈椎病预后的价值。方法对60例颈椎病患者前后路联合手术进行术中SEP监护,分析患者手术前、后的JOA评分及术前、术中、术终及恢复期的SEP变化,了解SEP变化与神经功能恢复之间的关系。结果15例（30．0％）术中潜伏期缩短或波幅增大,以上病人术后脊髓功能恢复良好,26例（52．0％）术前、术中、术终几乎无变化,8（16．0％）术中波幅有轻度下降,潜伏期轻度延长,术终又恢复到接近术前水平,1例（2．0％）术中有波幅下降和潜伏期延长,术后症状加重。术后随访SEP有潜伏期缩短或波幅明显增高的患者,临床症状改善明显。结论术中SEP的变化与患者的脊髓功能恢复有一定的关系。SEP可以作为颈椎病前后路联合手术的监护及预后判断的指标。     

脊髓前动脉损伤后运动诱发电位变化与病理学对照研究

目的：观察脊髓前动脉损伤后运动诱发电位（MEP）变化规律，以及相应的病理演变。方法：以浓犬为实验动物，采用颈前路手术入路，损伤脊髓前动脉。肉眼、镜下观察脊髓病理演变过程，测定脊髓前动脉损伤前、后MEP潜伏期，同时按Tarlov法测定肌力。结果：脊髓前动脉损伤后出现轴索断裂，髓鞘呈气球样空泡，脊髓水肿、出血，运动神经元变性坏死等病理性变化，脊髓前动脉损伤后立即出现不完全性肢体瘫痪，MEP潜伏期明显延长，3d后MEP的潜伏期有所恢复。结论：MEP对脊髓缺血性损伤后病理变化较敏感，MEP能准确地反遇脊髓缺血性损伤后运动功能的变化。     

NGF、BDNF基因修饰的BMSCs静脉注射治疗脊髓损伤

[目的]探讨神经生长因子（nerve growth factor，NGF）和脑源性神经生长因子（brain derived nerve growth factor，BDNF）基因修饰的骨髓基质细胞（bone marrow stem cells，BMSCs）静脉移植治疗脊髓损伤。[方法]SD大鼠制备成脊髓损伤动物模型。随机分为损伤对照组（A组）、BMSCs静脉移植组（B组）、NGF、BDNF基因修饰的BMSCs静脉移植组（C组）、正常对照组（D组）。治疗后2、6、10周，每组动物分别进行联合行为评分（GBS）、运动诱发电位（MEP）、感觉诱发电位（SEP）检查、双下肢功能测定（爬坡试验），评价脊髓损伤功能恢复情况。[结果]随时间的延长，C组GBS、MEP、SEP及下肢功能明显改善。与其他组相比较，差异有显著性，P〈0．05。[结论]NGF、BDNF基因修饰的BMSCs静脉移植能部分恢复损伤脊髓的功能。     

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。     

兔脊髓分级缺血-再灌注损伤对体感诱发电位的影响

目的 了解不同程度脊髓缺血-再灌注损伤与体感诱发电位（SEP）、神经功能评分及脊髓病理改变的关系。方法 将40只新西兰大耳白兔随机均分为4组，假手术组、缺血30min组、缺血45min组和缺血60min组。采用腹主动脉阻断法建立兔脊髓缺血-再灌注损伤模型，分别于缺血前、缺血5、10min、再灌注15、30min、1、2、24和48h监测SEP。于再灌注6、12、24和48h进行神经功能评分，再灌注48h进行脊髓病理学观察。结果 阻断腹主动脉血流30、45和60min后开放分别表现为轻、中、重度缺血-再灌注损伤脊髓的病理学改变特点。脊髓轻度缺血-再灌注损伤中SEP波幅和潜伏期分别于再灌注15和30min时恢复至缺血前水平（P〉0．05）；脊髓中度缺血-再灌注损伤中SEP波幅和潜伏期分别于再灌注30min和再灌注1h恢复至缺血前水平（P〉0．05）；脊髓重度缺血-再灌注损伤中SEP波幅和潜伏期分别明显下降和延长，与其他各组组间比较差异有统计学意义（P〈0.01）。各组神经功能评分组间比较差异均有统计学意义（P〈0. 01）。结论 脊髓缺血-再灌注损伤中SEP波幅较潜伏期恢复迅速。术中SEP监测能够敏感而准确地反映缺血-再灌注损伤中脊髓功能的变化，可为临床应用提供实验依据。     

大鼠不同程度高位颈脊髓损伤后膈肌运动诱发电位变化特点

目的了解不同程度高位颈髓损伤后大鼠膈肌运动诱发电位（MEP）的变化特点,分析以MEP评价高位颈髓损伤中MEP预测呼吸功能预后的价值。方法采用改良Allen法,分别以30gcf、50gcf、80gcf和100gcf冲量打击40只SD大鼠C3、4颈髓,造成不同程度的高位颈髓损伤。于伤前及伤后1个月连续记录膈肌MEP。观察MEP潜伏期及波幅的变化特点。同时采股动脉血,进行pH值、氧分压、二氧化碳分压及血氧饱和度的监测,了解不同程度的高位颈髓损伤大鼠呼吸功能的变化。分析不同程度的高位颈髓损伤后膈肌MEP潜伏期及波幅值的变化与呼吸功能预后的相关性。结果大鼠高位颈髓损伤前膈肌MEP波形稳定,通常包括1个正向波峰和负向波峰,其潜伏期和波幅平均值分别为（3．13±0.29）ins和（6．78±3．48）mv。不同程度高位颈髓损伤后MEP潜伏期不同程度改变,损伤越重,潜伏期越长。潜伏期变化与呼吸功能恢复显著相关。当MEP潜伏期延长超过101％时,呼吸功能很难恢复。结论MEP能较为客观、敏感地反映高位颈髓损伤后呼吸功能损伤程度,可以作为判断呼吸功能预后的可靠指标。     

体感诱发电位在颈椎病手术监护中的应用

目的：分析皮层体感诱发电位(somatosensory evoked potential,SEP)在颈椎病术中监护的应用价值及其在判断颈椎病预后中的作用。方法：对75例颈椎病患者术中行SEP监护，分析患者手术前、后的JOA评分及术前、术中、术终及恢复期的SEP变化，了解SEP变化与神经功能恢复之间的关系。结果：14例(18．7％)术中波幅有轻度下降，潜伏期轻度延长，术终又恢复到接近术前水平，51例(68％)术前、术中、术终几乎无变化，9例(12％)术中有明显恢复，以上多数病人功能恢复良好；1例(1．3％)术中有波幅下降和潜伏期延长，术后症状加重。在症状改善明显患者中，术后随访SEP均有潜伏期缩短或波幅明显增高。结论：SEP的变化与患者的神经功能恢复有一定的关系。SEP可以作为颈椎病术中监护及预后判断的指标。     

急性颈椎过伸伤伴中央脊髓综合征运动诱发电位特征及其与脊髓损伤程度的关系研究

目的研究颈椎过伸伤伴中央脊髓综合征(CCS)患者急性期运动诱发电位(MEP)特征及其与脊髓损伤程度的关系。方法回顾性分析2018年12月至2021年7月同济大学附属同济医院骨科收治的45例急性颈椎过伸伤伴CCS(观察组)患者资料和20例健康志愿者(健康对照组)资料。采用magpro x100型磁刺激仪对观察组患者和健康对照组受试者进行经颅磁刺激诱发的MEP检查, 在双侧拇短展肌进行记录。对比健康对照组, 描述观察组患者MEP波形的潜伏期、波幅及运动阈值的特点;分析观察组患者MEP潜伏期与脊髓损伤程度[美国脊髓损伤协会(ASIA)总分、运动功能(上肢运动评分UEMS)]的关系;根据MEP诱发状态不同, 将观察组患者分为静息组(n=19)、易化组(n=18)、无波形组(n=8), 比较组间的脊髓损伤程度(ASIA总分)和脊髓功能独立性(SCIM-Ⅲ得分), 并分析MEP诱发状态与脊髓损伤程度(ASIA总分)的关系。结果与健康对照组相比, 观察组患者MEP潜伏期[(30.16±6.32)ms]更长、波幅[(0.54±0.30)mV]更小、运动阈值(65%±11%)更高, 差异均有统计学意义(...     

早期手术减压对损伤脊髓caspase-3表达的影响

目的探讨大鼠脊髓损伤后不同减压时间对大鼠脊髓细胞caspase-3表达的影响。方法将动物分为:大鼠脊髓挫伤即刻手术减压组(A组),大鼠脊髓挫伤2小时手术减压组(B组),大鼠脊髓挫伤8小时手术减压组(C组),大鼠脊髓挫伤24小时手术减压组(D组)。手术后1、3、7、14、28天对脊髓损伤区进行细胞凋亡caspase-3蛋白表达的测定(免疫组化法),采用计算机图像分析技术,进行定量分析。并用行为学和电生理检查观察大鼠功能恢复情况。结果A、B、C、D四组中均发现凋亡caspase-3蛋白阳性表达细胞,图象分析发现,各组凋亡细胞caspase-3免疫反应阳性细胞表达顺序为D>C>B>A,与大鼠后肢功能恢复有平行的变化趋势。结论大鼠脊髓损伤早期手术减压能抑制脊髓损伤后的细胞凋亡,促进大鼠后肢功能恢复。     

经颅刺激运动诱发电位联合体感诱发电位监测在特发性脊柱侧凸矫形手术中应用的研究

背景：特发性脊柱侧凸手术治疗中神经功能障碍是最应受到关注的并发症,术中神经功能监测可帮助早期发现可能的神经功能损伤。目的：分析联合应用经颅刺激运动诱发电位（TcMEP）和体感诱发电位（SEP）的多模式术中神经功能监测在特发性脊柱侧凸矫形手术中对预测医源性神经功能损害的作用。方法：在特发性脊柱侧凸矫形手术中,运用TcMEP和（或）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％。结果：112例特发性脊柱侧凸患者中,联合MEP、SEP监测的检出率为100％。MEP监测阳性6例,假阳性1例。1例出现一过性神经功能障碍。MEP的监测敏感性为100％,特异性为99％;SEP监测敏感性50％,特异性为100％;联合MEP、SEP监测的敏感性、特异性均为100％。结论：特发性脊柱侧凸矫形手术中MEP＋SEP的术中神经功能监测可提高监测敏感性及特异性,可预测术中神经功能损伤事件的发生。MEP是多模式监测的基础,SEP是重要补充。单独应用MEP监测在特发性脊柱侧凸患者手术中有应用前景。     

Spinal cord contusion in the rat: somatosensory evoked potentials as a function of graded injury

A weight-drop technique was used to produce mild, moderate, or severe spinal cord contusive injury in rats. At 4 weeks after injury, somatosensory evoked potentials (SEPs) were recorded with silver ball electrodes placed over the somatosensory cortex of anesthetized rats to measure the response to sciatic nerve stimulation. Both SEP area and amplitude were measured and were highly correlated with each other. Both indices of the SEP correlated inversely with the height of the weight drop and directly with the degree of residual function assessed at 4 weeks after injury. Measures of residual function consisted of a motor score, inclined plane test, and a combined behavioral score based on several neurologic functions. No correlation between latency of the SEP with degrees of contusive injury was observed. The data indicate that the SEP can be used as one criterion in the assessment of the severity of a lesion in a rat model of a graded spinal cord injury.     

Intraoperative somatosensory evoked potential monitoring in scoliosis

During surgical correction of scoliosis, 63 patients had somatosensory evoked potential (SEP) monitoring of the spinal cord. Tibial nerves were unilaterally stimulated, and the potentials were recorded from the midcervical spine with surface and epidural needle electrodes. Over 85% had no significant change in their SEP and no postoperative neurologic deficits. Eleven percent had a significant change in their potential (amplitude decrease of greater than 60% and/or latency increase of greater than 2.5 msec) with no neurologic complications. One patient had a significant potential change and temporary postoperative sensory deficits did occur. One additional patient experienced postoperative neurologic complications but had no SEP change. This single false negative case, however, was clinically significant only for motor dysfunction, which is not monitored by the SEP. When changes in patient core temperature were compared to changes in SEP amplitude and latency, an intraoperative decrease in core temperature increased SEP latency and decreased amplitude, which may explain in part the false positive rate of the procedure.     

术中无肌松全静脉麻醉用于联合神经电生理监护脊柱手术的可行性

［摘要］ 目的 比较全静脉麻醉下术中使用或不使用肌松药对脊柱手术中联合神经电生理监测结果的影响,探讨安全有效的神经电生理监测麻醉方案。方法 选择拟行联合神经电生理监测的择期脊柱手术病人 40 例,分为A、B两组。两组病人均采用丙泊酚、瑞芬太尼和右美托咪定全凭静脉麻醉,A组病人术中使用小剂量阿曲库铵维持肌松,B组病人术中不使用肌松药。同时监测体感诱发电位（SEP）和运动诱发电位（MEP）评判脊髓功能。记录术中不同时间点两组病人的生命体征和SEP和MEP的波幅和潜伏期,同时记录经颅电刺激时病人是否出现剧烈体动和自主呼吸。比较两组病人术毕后麻醉苏醒时间和质量。结果 两组病人不同时间点的生命体征差异无统计学意义。两组病人的SEP的波幅和潜伏期差异无统计学意义,MEP的潜伏期差异无统计学意义,MEP的波幅差异有显著性统计学意义。两组病人在电刺激时均无自主呼吸和剧烈体动发生。结论 术中不使用肌松药的全静脉麻醉方案可安全有效地用于行神经电生理监测的脊柱手术,并且在电生理监测信号质量和术后苏醒方面具有明显优势。     

大剂量维生素C联合小剂量甲基强的松龙对脊髓损伤后脊髓病理生理变化的影响

[目的]探讨脊髓受压及减压后,大剂量维生素C(vitaminC)联合小剂量甲基强的松龙(MP)对脊髓灰质血流量,体感诱发电位(SEP),组织学变化,运动功能的影响.[方法]36只犬随机分为3组,每组12只.A组于SEP消失后5min静脉注射MP 30 mg/kg,以5.4 mg (kg·h)输液泵静脉注射;B组于SEP消失后5min以同样方式注射vitaminC 200 mg/kg+ MP 10 mg/kg,减压后12 h,24h各注射vitaminC 200 mg/kg;C组于SEP消失后5min静脉注射0.9％氯化钠,同样以5.4 mg(kg·h)输液泵静脉注射.均持续90 min后减压,期间检测SEP及脊髓灰质血流量,减压后3h重复检测,并进行改良Tarlov评分.减压后28 d通过病理组织学分析确定损伤的范围.[结果]在持续压迫期间A组4只犬出现了SEP,B组5只犬出现了SEP,C组无一出现.减压后A组有2只犬出现SEP,B组有2只犬出现SEP,C组有1只犬出现SEP.三组犬中出现SEP的脊髓灰质血流量明显高于没有出现SEP的犬(P＜0.05).A、B组脊髓灰质血流量明显高于C组(P＜0.05).A、B组动物后肢的运动功能可以较快恢复,C组不能恢复.A、B组脊髓损伤范围与C组具有显著性差异,病理改变与SEP及脊髓血流量具有相关性,与运动功能的恢复具有相关性.[结论]大剂量维生素C与小剂量甲基强的松龙联合应用在神经功能保护及恢复方面提供了显著持续的作用,可能增加了脊髓局部的血流量.维生素C可以部分替代甲基强的松龙对于脊髓损伤的作用.     

体感诱发电位评价家兔脊髓冲击伤模型的神经机能变化

目的 探讨脊髓冲击伤前后的体感诱发电位的变化,评价家兔神经机能的改变程度.方法 应用改良霍普金森杠杆设备根据冲击波的压力不同(0.40 MPa,0.60 MPa,0.80 MPa)建立不同损伤程度的胸T9-T10脊髓冲击伤模型,12 h后用体感诱发电位仪分别计测家兔脊髓冲击伤前后的体感诱发电位,利用分析软件对诱发电位P...     

Failure of motor evoked potentials to predict neurologic outcome in experimental thoracic aortic occlusion

Motor evoked potential monitoring was tested as an alternative to somatosensory evoked potential monitoring in evaluating spinal cord function during thoracic aortic occlusion in dogs. Twenty-seven animals underwent 60 minutes of cross-clamping of the proximal descending thoracic aorta with (n = 18) or without (n = 9) cerebrospinal fluid drainage. Spinal cord blood flow was measured with microspheres, and neurologic outcome was evaluated at 24 hours with Tarlov's scoring system. Cerebrospinal fluid drainage improved neurologic outcome (p less than 0.05). Motor evoked potentials recorded over the lumbar spinal cord were lost in 9 of 20 dogs with ischemic cord injury and were not lost in any of the 7 dogs that were neurologically normal. Somatosensory evoked potential were lost in 19 of 20 paraplegic/paraparetic dogs and lost in 3 of 7 normal dogs (p less than 0.01). After reperfusion, motor evoked potentials returned in all nine neurologically injured dogs that lost the potentials and were still present at 24 hours. Changes in amplitude, latency, or time until loss or return of motor evoked potentials or somatosensory evoked potentials did not predict neurologic injury. Loss of somatosensory evoked potentials had a high sensitivity (95%) but had low specificity (67%) because of peripheral nerve ischemia. Loss of motor evoked potentials recorded from the spinal cord had high specificity (100%) but a low sensitivity (46%) and was therefore not a reliable predictor of neurologic injury. Return of motor evoked potentials during reperfusion did not correlate with functional recovery. Motor evoked potentials stimulated in the cortex and recorded from the spinal cord had low overall accuracy (59%).(ABSTRACT TRUNCATED AT 250 WORDS)     

Motor and Somatosensory Evoked Potentials Are Well Maintained in Patients Given Dexmedetomidine during Spine Surgery

Background: Many commonly used anesthetic agents produce a dose-dependent amplitude reduction and latency prolongation of evoked responses, which may impair diagnosis of intraoperative spinal cord injury. Dexmedetomidine is increasingly used as an adjunct for general anesthesia. Therefore, the authors tested the hypothesis that dexmedetomidine does not have a clinically important effect on somatosensory and transcranial motor evoked responses.

Methods: Thirty-seven patients were enrolled and underwent spinal surgery with instrumentation during desflurane and remifentanil anesthesia with dexmedetomidine as an anesthetic adjunct. Upper- and lower-extremity transcranial motor evoked potentials and somatosensory evoked potentials were recorded during four defined periods: baseline without dexmedetomidine; two periods with dexmedetomidine (0.3 and 0.6 ng/ml), in a randomly determined order; and a final period 1 h after drug discontinuation. The primary outcomes were amplitude and latency of P37/N20, and amplitude, area under the curve, and voltage threshold for transcranial motor evoked potential stimulation.

Results: Of the total, data from 30 patients were evaluated. Use of dexmedetomidine, as an anesthetic adjunct, did not have an effect on the latency or amplitude of sensory evoked potentials greater than was prespecified as clinically relevant, and though the authors were unable to claim equivalence on the amplitude of transcranial motor evoked responses due to variability, recordings were made throughout the study in all patients.     

Somatosensory evoked potentials and spinal cord perfusion pressure are significant predictors of postoperative neurologic dysfunction

Paraplegia after thoracoabdominal aneurysm repair can occur in 3% to 40% of patients. This study investigated the efficacy of cerebrospinal fluid (CSF) drainage to protect the spinal cord during aortic cross-clamping (AXC) and the interrelationship between drainage, spinal cord perfusion pressure (SCPP), and changes in somatosensory evoked potentials (SEP) in a canine model of spinal cord ischemia. SCPP was defined as the mean distal aortic pressure minus the CSF pressure. In the experimental group, CSF was drained before AXC. SEP changes were quantitated as time to latency increase of 10% (L-10) and time to complete SEP loss. Drainage of CSF had no significant effect on the distal aortic pressure but significantly increased SCPP from 9.4 to 21.8 mm Hg and decreased the incidence of postoperative neurologic injury. Ischemic SEP changes were highly significant predictors of postoperative neurologic injury, occurring more than two times earlier in the paralyzed and paraparetic animals. Dogs without neurologic injury had significantly higher SCPP, delayed L-10 time, and delayed SEP loss.