脑皮层运动诱发电位实验研究

目的探讨对脑中央区皮层进行皮层电位诱发的最佳刺激参量。方法使用皮层电极在10只新西兰雄兔中央后回感觉皮层对应部位记录N20-P25波,沿中央后回运动区皮层向前移动电极直至记录到一个波型相反、波幅相近、位相倒置的波型(P20-N25波),定为运动中枢刺激点。使用不同刺激参量直接刺激该点,在上肢掌长肌记录运动诱发电位(MEP)。结果10只新西兰雄兔均记录到N20-P25波和P20-N25波,并成功诱发MEP。各组高频串刺激的刺激电流阈值均低于单波刺激,差异有统计学意义(P<0.05)。结论MEP是一种安全、有效的监测方法;高频串刺激在脑中央区皮层MEP监护中优于单波刺激;当串刺激参量限于一定范围(时程0.2～0.3 ms,频率300～500 Hz,方波个数3～5个)时,均能安全、有效地诱导出皮层MEP。     

联合应用Co—SEP、MEP和ECoG监测指导功能区继发性癫痫手术

目的：探讨联合应用诱发电位和皮层脑电监测技术对功能区继发性癫痫外科手术的指导作用。方法：对14例中央区病变的继发性癫痫患者在术中行皮层体感诱发电位（Co—SEP）及皮层电刺激运动诱发电位（MEP）检查以定位脑功能区;皮层脑电图（ECoG）监测界定致痫灶皮层区域。结景：14例均通过Co—SEP位相倒置界定中央沟位置,并电刺激中央前回,分别于口轮匝肌、大鱼际肌、小鱼际肌及趾短屈肌处引出MEP,以此指导的手术在切除病变及致痫组织时避开中央区的损害;并在ECoG监测下指导病灶周围致痫区皮层的手术治疗。术后观察1-2周,患者癫痫发作均较前明显减少或消失;2／14例（14．29％）术后出现一过性失语或肢体无力,余病例无神经功能障碍。结论：术中联合应用Co—SEP、MEP和ECoG监测指导重要脑功能区继发性癫痫手术是安全有效的,可为手术提供成功的保障。     

多点刺激法和递增法运动单位数目估计在肌萎缩侧索硬化患者中的比较

目的 比较多点刺激法和递增法运动单位数目估计(MUNE)在肌萎缩侧索硬化(ALS)患者中的差异.方法 60例肌萎缩侧索硬化患者和60名健康人进行多点刺激法和递增法运动单位数目估计.表面记录电极置于拇短展肌.多点刺激法:刺激电极分别于腕,腕上6 cm,肘,肘上6 cm四点刺激正中神经,以超强刺激诱发最大波幅M波;然后从0刺激开始逐渐增加刺激强度直到出现可辨认的单个运动单位电位,逐渐增大刺激强度,记录3个递增的M波.递增法:刺激电极在腕点刺激正中神经,以超强刺激诱发最大M波值,之后自阈强度刺激开始,逐渐增加刺激强度,收集10个递增的M波.结果 正常对照组拇短展肌运动单位数目估计(MUNE)结果:228±30(多点刺激法,相关系数为0.88～0.91,变异系数13.20%～15.24%);198±26(半自动递增法,相关系数为0.86,变异系数13.30%～15.65%).ALS患者拇短展肌MUNE结果为64±6(多点刺激法);59±7(半自动递增法).结论 此两种运动单位数目估计检测方法可重复性良好,可用于肌萎缩侧索硬化患者的监测.     

神经电生理监测技术联合神经导航技术在大脑中央区病变手术中的应用

目的探讨神经电生理监测技术联合神经导航技术在大脑中央区病变手术治疗中的应用价值。方法对11例大脑中央区病变患者,在手术中选择性应用神经导航和神经电生理监测技术（头皮体感诱发电位、皮质体感诱发电位、头皮运动诱发电位、头皮直接皮质电刺激）定位功能区,显微操作下切除病灶。结果术中行神经导航8例（其中4例行基于锥体束成像的功能神经导航）;行头皮体感诱发电位监测7例,1例波幅下降,调整操作后恢复;行皮质体感诱发电位监测8例,5例能记录到位相倒置波形或主波渐变波形;行头皮运动诱发电位监测2例,直接皮层刺激共4例,1例能引发肢体运动和（或）肌电反应。病变全部切除8例,近全切除1例,大部分切除2例。术后有8例患者症状改善,3例症状无恶化,所有患者均未出现新发神经功能障碍。结论在大脑中央区病变手术中,神经电生理监测技术联合神经导航技术可精确定位病灶和重要感觉运动功能区,能有效提高手术效果,保障手术安全,减少术后神经功能缺失。     

Motor cortex stimulation in the treatment of central and neuropathic pain

BACKGROUND: Motor cortex stimulation has been proposed for the treatment of central pain. METHODS: Thirty-two patients with refractory central and neuropathic pain of peripheral origin were treated by chronic stimulation of the motor cortex between May 1993 and January 1997. The mean follow-up was 27.3 months. The first 24 patients were operated on according to the technique described by Tsubokawa. The last 13 cases (8 new patients and 5 reinterventions) were operated on by a technique including localization by superficial CT reconstruction of the central region and neuronavigator guidance. The position of the central sulcus was confirmed by the use of intraoperative somatosensory evoked potentials. The somatotopic organization of the motor cortex was established preoperatively by studying the motor responses at stimulation of the motor cortex through the dura. RESULTS: Ten of the 13 patients with central pain (77%) and 10 of the 12 patients with neuropathic facial pain experienced substantial pain relief (83.3%). One of the three patients with post-paraplegia pain was clearly improved. A satisfactory result was obtained in one patient with pain related to plexus avulsion and in one patient with pain related to intercostal herpes zoster. None of the patients developed epileptic seizures. CONCLUSIONS: Our results confirm that chronic stimulation of the motor cortex is an effective method in treating certain forms of refractory pain.     

体感诱发电位与运动诱发电位在胸椎结核手术中联合应用的价值

目的探讨皮层体感诱发电位(CSEP)和经头颅电刺激运动诱发电位(TES-MEP)在胸椎结核患者术中联合应用的价值。方法对27例胸椎结核患者行术中CSEP+TES-MEP联合监护。术中持续观察CSEP及TES-MEP波幅及潜伏期变化,出现波幅下降50%、潜伏期延长10%或刺激强度高于初始刺激强度100 V仍未引出者,停止手术并对症处理。结果 CSEP监测成功率为100.0%(27/27),TES-MEP监测成功率为92.6%(25/27),联合监测成功率为92.6%(25/27),CSEP阳性1例,TES-MEP阳性7例,其中,CSEP+TES-MEP均为阳性的1例,CSEP阴性而TES-MEP阳性6例,术后神经功能损伤1例。结论胸椎结核患者术中联合运用CSEP和TES-MEP监测,排除各种干扰因素后,能准确地反映术中脊髓功能状况,提高监护效果。     

Combined monitoring of evoked potentials during microsurgery for lesions adjacent to the brainstem and intracranial aneurysms

Background Neurophysiologic monitoring during surgery is to prevent permanent neurological injury resulting from surgical manipulation. To improve the accuracy and sensitivity of intraoperative neuromonitoring, combined monitoring of transcranial electrical stimulation motor evoked potentials (TES-MEPs), somatosensory evoked potentials (SSEPs) and brainstem auditory evoked potentials (BAEPs) was attempted in microsurgery for lesions adjacent to the brainstem and intracranial aneurysms.Methods Monitoring of combined TES-MEPs with SSEPs was attempted in 68 consecutive patients with lesions adjacent to the brainstem as well as intracranial aneurysms. Among them, 31 patients (31 operations, 28 of posterior cranial fossa tumors, 3 of posterior circulation aneurysms) were also subjected to monitoring of BAEPs. The correlation of monitoring results and clinical outcome was studied prospectively.Results Combined monitoring of evoked potentials (EPs) was done in 64 (94.1％) of the 68 patients. MEPs monitoring was impossible for 4 patients (5.9%). No complication was observed during the combined monitoring in all the patients. In 45 (66.2%) of the 68 patients, EPs were stable, and they were neurologically intact. Motor dysfunction was detected by MEPs in 8 patients, SSEPs in 5, and BAEPs in 4, respectively. Conclusions A close relationship exists between postoperative motor function and the results of TES-MEPs monitoring. TES-MEPs are superior to SSEPs and BAEPs in detecting motor dysfunction, but combined EPs serve as a safe, effective and invasive method for intraoperative monitoring of the function of the motor nervous system. Monitoring of combined EPs during microsurgery for lesions adjacent to the brainstem and intracranial aneurysms may detect potentially hazardous maneuvers and improve the safety of subsequent procedures.     

电刺激运动诱发电位(MEP)临床研究进展

 运动诱发电位(motor evoked potential,MEP)应用于临床已有二十多年的历史,其中电刺激MEP广泛地应用于运动神经系统疾病的诊断和术中监护。随着监测技术和麻醉技术的进步,电刺激MEP术中监测的价值和可靠性进一步提高,应用范围越来越广,安全性也得到不断改善。但目前仍存在一些问题,如缺乏统一的预警标准,多学科的合作不足等。本文就MEP术中应用的现状、安全性及麻醉对它的影响进行综述。     

电刺激与损毁兔中脑导水管周围灰质不同部位对皮层牙髓诱发电位及其针刺抑制效应的影响

以电刺激牙髓引起兔皮层体感区诱发电位作为痛反应指标,观察中脑导水管周围灰质(PAG)不同部位对痛反应及针刺镇痛的影响。实验结果表明,电刺激PAG外侧区或腹侧区,均引起诱发电位的抑制,且以在腹侧区的作用最显著,刺激背侧区则未见明显影响。在损毁PAG腹侧区后,电针对皮层诱发电位的抑制作用显著减弱或消失,而损毁外侧区及背侧区后,电针的抑制作用未见明显变化。。     

脊髓病变的运动诱发电位研究及其应用探讨

目的 探讨脊髓病变的运动诱发电位（ＭＥＰ）及其临床应用。方法 采用经颅和椎骨的电刺激技术检查１９例脊髓病变患者上下肢的ＭＥＰ反应。结果 对锥体束产生压迫和（或）破坏的病变、可造成潜伏时和中枢运动传导时间延长,波幅降低。下肢异常比上肢异常明显。异常改变在肢体的分布与病变部位密切相关。结论 ＭＥＰ可作为脊髓病变的神经电生理诊断手段。     

颈髓慢性病变对磁刺激运动诱发电位的影响

目的：探索磁刺激运动诱发电位（ＭＥＰ）在颈髓髓内和髓外病变中的诊断价值。方法：对３７例颈髓病患者进行前瞻性临床调查,包括颈椎病（ｎ＝２１）,颈椎管狭窄症（ｎ＝６）,颈椎及颈髓肿瘤（ｎ＝６）和脊髓空洞症（ｎ＝４）,和对照组２０例,结果：３１例髓外病变者,１９例（６１．３％）上肢拇展短肌（ＡＰＢ）中枢运动传导速度（ＣＭＣＴ）异常,２１例（６７．７％）下肢胫骨前肌（ＡＴ）ＣＭＣＴ异常;６例髓内病变者,２     

Evoked spinal cord potentials monitored at thoracoabdominal region after trans-intercostal stimulation

To investigate the feasibility of a novel recording method for trans-intercostal evoked spinal cord potentials (Tic-ESCPs) and the properties of the waveforms, the potentials were recorded and analyzed in an animal model. In two beagle dogs, Tic-ESCPs were recorded at the left twelfth intercostal to fourth lumbar nerves following stimulation at the left eleventh intercostal nerve, either with or without the use of a muscle relaxant. The amplitude and latency of the Tic-ESCP waves were then measured and compared with those of conventional transcranial spinal motor evoked potentials (MEPs). Tic-ESCPs could be obtained at any nerve, with or without the use of a muscle relaxant. The Tic-ESCP waveform was clear and simple, consisting of a small positive (P1) wave and a subsequent large negative (N1) wave. As the site of recording moved farther from the stimulation site, the N1 amplitudes were reduced and the P1 latency was prolonged. Under muscle relaxation, the N1 amplitudes were reduced, and the P1 latencies were shorter. As compared with MEPs, Tic-ESCPs could be evoked by a weaker stimulus, the N1 amplitude was smaller, and the P1 latency was shorter. Tic-ESCP recording was feasible either with or without the use of a muscle relaxant. The Tic-ESCPs showed simple and clear waveforms with smaller stimulations. Therefore, Tic-ESCPs may be useful for intraoperative spinal cord monitoring.     

皮层电极监测、图像融合和术中磁共振精确镜下导航技术在切除功能区癫痫灶的应用

目的 探讨颅内皮层电极监测、图像融合和术中磁共振精确导航技术在切除功能区癫痫灶的应用价值.方法 回顾分析25 例应用皮层电极监测、图像融合和术中磁共振精确导航技术外科治疗的顽固性癫痫病例,第1 次手术,根据动态视频脑电图监测结果,埋置颅内皮层电极与可能癫痫放电区域,术后进行皮层脑电监测、皮层电刺激定位躯体运动区,绘制病灶与功能区关系图,而后将CT、MRI、MEG 或PET 图像融合,在术中MRI 镜下导航行致痫病灶的精确切除.结果 25 例第1 次术后成功实施皮层电刺激,准确定位癫痫病灶周边的运动功能区.将患者的MRI、MEG 或PET 图像进行融合,20 例在术中MRI 镜下导航将术前所确定的癫痫灶全部切除,5 例因病灶与功能区有部分重叠,行癫痫灶部分切除,残余少许皮层小功率热灼.1 例术后出现一过性对侧肢体功能障碍,所有患者术后无永久神经功能缺失.结论 颅内皮层电极监测对癫痫灶的精确定位意义重大,而图像融合和术中MRI 镜下导航为患者癫痫灶的精确切除和功能区保护提供了强有力的技术支持.     

枕骨大孔区病变与运动诱发电位的研究

目的：了解枕骨大孔区病变运动诱发电位表现，方法；对经核磁共振（ＭＲＩ）证实的５１例枕骨大孔区病变患者，进行了电刺激运动诱发电位（ＭＥＰ）测试。结果：枕骨大孔区病变患者ＭＥＰ异常率为９４．１％，表现为潜伏期延长，中枢运动的传导时间（ＣＭＣＴ）延长，波幅降低，枕骨大孔区肿瘤中，颈延型肿瘤的ＭＥＰ异常较延颈型肿瘤的ＭＥＰ异常更显著，腹侧肿瘤的ＭＥＰ异常较侧后方的ＭＥＰ异常更显著。结论：ＭＥＰ改变较临床评     

枕骨大孔区髓外肿瘤患者的电刺激运动诱发电位研究

探讨枕骨大孔区髓外肿瘤患者的电刺激运动诱发电位表现。方法对经核磁共振影像（ＭＲＩ）证实的２２例枕骨大孔区髓外肿瘤患者进行了电刺激运动诱发电位（ＭＥＰ）测试。结果枕骨大孔区髓外肿瘤患者的ＭＥＰ异常率为９５．５％,表现为潜伏期延长,中枢运动传导时间（ＣＭＣＴ）延长,波幅降低。ＭＥＰ的异常表现与肿瘤部位有关。结论ＭＥＰ改变较临床评估更为敏感,且能客观定量地反映运动功能的损害程度。ＭＥＰ可预测预后,能作为评价手术效果的客观指标     

Three core techniques in surgery of neuroepithelial tumors in eloquent areas: awake anaesthesia, intraoperative direct electrical stimulation and ultrasonography

Background  The goal of surgery in the treatment of intrinsic cerebral tumors is to resect the maximum tumor volume, and to spare the eloquent areas. However, it is difficult to discover the eloquent areas intraoperatively due to individual anatomo-functional variability both for sensori-motor and language functions. Consequently, the surgery of intrinsic cerebral tumors frequently results in poor extent of resection or permanent postoperative deficits, or both, and remains a difficult problem for neurosurgeons.

Methods  From January 2003 to January 2010, 112 patients with neuroepithelial tumors in/close to the eloquent areas were operated on under awake anesthesia with the intraoperative direct electrical stimulation for functional mapping of the eloquent areas. The extent of the tumors was verified by intraoperative ultrasonography. The maximal resection of the tumors and minimal damage of the eloquent areas were the surgical goal of all patients.

Results  Totally 356 cortical sites in 99 patients were detected for motor response by intraoperative direct electrical stimulation, 50 sites in 16 patients for sensory, 72 sites in 48 patients for language. Sixty-six patients (58.9%) achieved total resection, 34 (30.4%) subtotal and 12 (10.7%) partial. Fifty-eight patients (51.8%) had no postoperative deficit, while 37 patients (33.0%) had transitory postoperative paralysis, 26 patients (23.2%) with transitory postoperative language disturbance and 3 patients (2.7%) with permanent neurological deficits. No patient complained of pain recollection following operation.

Conclusions  Awake anesthesia, intraoperative direct electrical stimulation and ultrasonography are three core techniques for the resection of intrinsic cerebral tumors near the eloquent areas. This new concept allows an improvement in the quality of surgery for neuroepithelial tumors in/adjacent to eloquent areas.

     

胸椎脊髓损伤电生理和临床感觉检查的进展

胸椎脊髓损伤电生理检查主要集中在颅磁刺激器引出运动诱发电位(MEP),有小鱼际肌群MEP、立干肌MEP、肋间肌MEP和腹内斜肌MEP,检查完全和不完全脊髓损伤病例损伤平面上及下方的立干肌,可检出损伤平面以下临床上尚无恢复迹象、而有电生理恢复的立干肌,同时显示同侧立干肌、腹内斜肌受同侧未交叉纤维的皮质脊髓束支配情况.临床感觉检查中的皮肤电刺激感知阈检查比2点鉴别试验准确,对脊髓损伤患者的损伤平面上及下行定量感觉检查包括震动感阈值、轻触觉、温觉检查,疼痛和皮肤轴突感觉反射,在完全和不完全脊髓损伤患者,损伤平面以上温觉有改变,其阈值升高.     

Electrocorticography with direct cortical stimulation for a left temporal glioma with intractable epilepsy

ELECTROCORTICOGRAPHY (ECoG),the intraoperative recording of cortical potentials,has played an important role in the surgical management of patients with medically intractable epilepsy.This technique is useful in epilepsy surgery to delineate margins of epileptogenic zones,guide resection,and evaluate completeness of resection.1 About one third of the patients with intractable epilepsy have obvious causes,such as tumor,sclerosis,or vascular malformation.However,the presence of tumor in the eloquent cortex like speech area makes it challenging to completely resect the tumor.ECoG-based surgery in conjunction with direct cortical stimulation in such cases helps surgical resection of tumor with no functional tissue affected,producing good surgical outcome.This report describes a case treated with ECoG-based surgery in combination with direct cortical stimulation.     

Surgical strategies for glioma involving language areas

Background Successful treatment of gliomas in or adjacent to language areas constitutes a major challenge to neurosurgery. The present study was performed to evaluate the procedure of language mapping via intraoperative direct cortical electrical stimulation under awake anaesthesia when performed prior to resective glioma surgery. Methods Thirty patients with gliomas and left-hemisphere dominance and, who underwent language mapping via intraoperative direct cortical electrical stimulation under awake anaesthesia before resective glioma surgery, were analyzed retrospectively. All patients had tumors in or adjacent to cortical language areas. The brain lesions were removed according to anatomic-functional boundaries with preservation of areas of language function. Both preoperative and postoperative functional findings were evaluated. Results Intraoperative language areas were detected in 20 patients but not in four patients. Language mapping failure for reasons attributable to the anaesthesia or to an intraoperative increase in intracranial pressure occurred in six cases. Seven patients presented with moderate or severe language deficits after six months of follow-up. Total resection was achieved in 14 cases, near-total resection in 12 cases and subtotal resection in four cases. Conclusions Intraoperative cortical electrical stimulation is an accurate and safe approach to identification of the language cortex. Awake craniotomy intraoperative cortical electrical stimulation, in combination with presurgical neurological functional imaging to identify the anatomic-functional boundaries of tumor resection, permits extensive tumor excision while preserving normal language function and minimizing the risk of postoperative language deficits.     

Preoperative blood oxygen level-dependent functional magnetic resonance imaging in patients with gliomas involving the motor cortical areas

Background Blood oxygen level-dependent （BOLD） functional magnetic resonance imaging （fMRI） plays an important role in identifying functional cortical areas of the brain, especially in patients with gliomas. This study aimed to assess the value of fMRI in presurgical planning and functional outcome of patients with gliomas in the motor cortical areas. Methods Twenty-six patients with gliomas in the motor cortex were recruited in the study. Before operation, fMRI was performed in each patient to obtain the mapping of bilateral hands area on the primary sensorimotor cortex. This examination was performed on a 3.0T scanner with a bilateral hands movement paradigm. During microsurgery under awake anesthesia, the motor area was identified using direct electrical stimulation and compared with preoperative mapping. Finally the tumor was resected as much as possible with the motor cortex preserved in each patient. Karnofsky performance status （KPS） was evaluated in all patients before and after operation. Results Twenty-three patients showed a successful fMRI mapping. Among them, 19 were calssified to be grade Ⅲ; 4, grade Ⅱ; 3, grade Ⅰ. The operation time was about 7 hours in the 23 patients, 8.5 hours in the other 3. The pre-and postoperative KPS score was 82.3±8.6 and 94.2±8.1, respectively. Conclusions Preoperative fMRI of the hand motor area shows a high consistency with intraoperative cortical electronic stimulation. Combined use of the two methods shows a maximum benefit in surgical treatment.