重症肌无力伴Lambert-Eaton肌无力综合征8例分析

目的探讨重症肌无力(MG)合并Lambert—Eaton肌无力综合征(LEMS)的临床特点。方法回顾性分析8例MG合并LEMS患者的发病形式、首发症状、1临床表现和实验室及辅助检查。结果8例患者均慢性或亚急性起病，首发症状表现为双下肢无力4例(50％)。四肢无力4例(50％)，经过症状有球麻痹1例，睑下垂1例，面肌受累及呼吸困难各1例；8例患者伴癌6例(75％)，其中5例(62.5％)为肺癌；所有患者新斯的明试验( )，重复神经电刺激均示低频(2Hz、3Hz、5Hz)衰减(17％～40％)，高频(20Hz、30Hz)递增(200％～881％)。结论对以双下肢无力首发的MG，均应考虑到LEMS或合并LEMS的可能，常规行重复神经电刺激，确诊为LEMS后，应常规行胸部CT和／或腹部B超检查以早期发现肿瘤。     

糖皮质激素治疗重症肌无力早期致病情加重的临床观察

目的观察甲基强的松龙冲击疗法(MPPT)治疗重症肌无力(MG)早期导致一过性肌无力加重的作用.方法对MPPT治疗的36例MG患者于治疗前及治疗后肌无力加重时分别进行临床评分、低频重复电刺激、血清AChRAb滴度检查.结果MPPT治疗MG后,1周时临床显效率58%,4周时临床显效率为78%,有效率为94%;部分患者出现一过性肌无力加重;加重后低频重复电刺激波幅递减幅度较加重前明显增加(P<0.05),而血清AChRAb滴度无明显变化(P>0.05).结论MPPT治疗MG,56%患者早期可出现不同程度的一过性肌无力加重,其中轻～中度加重占65%,重度加重占35%,14%累及呼吸肌,6%出现MG危象;加重多出现于治疗后的1～7(3±2)d,持续时间1～18(4±3)d;早期一过性肌无力加重可能与激素直接抑制神经-肌接头处传递有关.     

50例重症肌无力患者近端神经低频重复电刺激的比较

对50例确诊为重症肥无力（MG）患者腹神经和副神经低频（3Hz、5Hz）重复电刺激（RNS）结果表明，在不同频率刺激下，所有患者腋神经的平均衰减幅度均大于副神经的平均衰减幅度，50例患者腋神经RNS均为阳性，而副神经RNS阳性者仅33例，说明应用RNS检查诊断MG时，腋神经的敏感性高于副神经。此外，对两种检查方法及其结果的可靠性进行了讨论。     

糖皮质激素冲击治疗后重症肌无力早期一过性加重的机制研究

目的 探讨糖皮质激素冲击(GI)治疗后重症肌无力(MG)早期一过性加重的机制.方法 选取2012年1月～2013年6月诊治的125例MG患者,并给予GI治疗,统计分析并进行治疗前后临床评分和血清抗胆碱受体抗体滴度(AchR-Ab)、免疫球蛋白IgG和补体C3水平、肌电图检测.结果 GI治疗MG后,7天有效率为57.78％,28天有效率为75.56％,其中肌无力一过性加重发生率为36.0％;肌无力加重后患者临床绝对评分明显高于加重前,差异具有统计学意义(P＜0.05);桡神经和腋神经低频重复电刺激波幅递减程度明显高于加重前,差异具有统计学意义(P＜0.05);加重前后患者血清AchR-Ab、IgG和C3水平差异均无统计学意义(P＞0.05).结论 GI治疗MG后,具有早期一过性加重发生的风险,这可能与激素抑制神经递质的传递有关,但与体内抗体、补体水平变化无关.     

重症肌无力并发胸腺外霍奇金淋巴瘤一例

临床资料患者男性,26岁.以"左上眼睑下垂、复视11年,呼吸困难4d,加重1d"于2008年2月16日入院.患者于11年前无诱因出现左上眼睑下垂、复视,晨轻暮重,无四肢乏力、饮水呛咳、吞咽困难等,重复神经电刺激未见明显异常,诊断"重症肌无力(MG)".     

17例重症肌无力患者的重复神经电刺激检查结果分析

目的 分析重症肌无力患者不同神经重复电刺激的阳性率。方法 对17例重症肌无力患者31例神经做低频和高频率重复电刺激测定。结果 面神经重复电刺激阳性率大于尺神经。3Hz和5Hz频率刺激波幅衰减最大。结论 尺神经 面神经重复电刺激可提高重症肌无力诊断的阳性率。     

儿童重症肌无力56例重复神经电刺激检测分析

目的探讨儿童重症肌无力(MG)重复神经电刺激(RNS)特点及临床应用价值。方法应用肌电图/诱发电位仪对56例MG患儿分别进行双侧面神经、腋神经及尺神经1Hz、3Hz、5Hz、10Hz频率电刺激,观察其复合肌肉动作电位(CMAP)第4波与第1波比较的波幅降低百分比,比较患儿不同MG类型、不同神经以及面神经不同频率刺激的RNS阳性率,分析5Hz刺激面神经时各型患儿CMAP幅值衰减的变化及不同分型与幅值衰减的相关性。结果 56例MG患儿共检测270条神经,RNS总阳性率为73.21%(41/56)。Ⅰa型、Ⅰb型、Ⅱa型MG类型RNS阳性率分别为62.96%(17/27)、75.00%(12/16)、92.31%(12/13),组间两两比较差异均有统计学意义(均P0.05)。面神经、腋神经、尺神经RNS阳性率分别为73.21%(41/56)、60.87%(14/23)、8.93%(5/56),组间两两比较差异均有统计学意义(均P0.05)。1、3、5、10 Hz电刺激时面神经RNS阳性率分别为42.86%(24/56)、53.57%(30/56)、58.93%(33/56)、23.21%(13/56),组间两两比较,1Hz、3Hz、5Hz电刺激时RNS阳性率均高于10Hz电刺激时(均P0.05),3 Hz、5 Hz电刺激时RNS阳性率均高于1 Hz电刺激时(均P0.05),3Hz电刺激时与5Hz电刺激时比较RNS阳性率差异无统计学意义(P0.05)。5 Hz刺激时Ⅰa型、Ⅰb型、Ⅱa型患儿面神经RNS衰减的幅值分别为(19.14±3.27)%、(24.55±5.34)%、(52.13±10.49)%,组间两两比较差异均有统计学意义(均P0.05),并且3型患儿面神经RNS衰减的幅值与患儿分型有相关性(r=0.744,P=0.000)。结论 RNS是一项无痛无创、相对不需要患儿配合、敏感度较高的电生理检查,客观性较强且能量化观察指标;3Hz、5Hz电刺激时面神经RNS检测阳性率较高;儿童检测操作方法的改进有助于提高其阳性率。     

全身型重症肌无力的临床和电生理特点分析

目的 探讨不同亚型全身型重症肌无力(Myasthenia gravis,MG)临床和电生理特点之间的区别,并分析电生理结果与疾病严重程度的相关性。方法 回顾性分析2016年7月至2020年7月在香港大学深圳医院神经内科就诊或住院的101例全身型MG患者的临床和电生理资料,按照其临床特点,分为早发乙酰胆碱受体(Acetylcholine receptor,AchR)抗体阳性全身型MG组(52例)、晚发AchR抗体阳性全身型MG组(23例)、胸腺瘤型MG组(22例)和肌肉特异性受体酪氨酸激酶(Muscle-specific receptor tyrosine kinase,MuSK)抗体阳性型MG组(4例),比较不同亚组MG患者的人口学特点、重症肌无力评分(Quantitative Myasthenia Gravis score,QMGs)、美国重症肌无力协会(MG Foundation America,MGFA)临床分级、重复神经电刺激(Repetitive nerve stimulation,RNS)结果,分析RNS结果与QMGs之间的相关性。结果 非MuSK抗体阳性全身型MG中,早发AchR抗体阳性全身型MG女性患者所占比率最高(71. 2%vs 65. 2%vs 36. 4%,P 0. 05),胸腺瘤型MG呼吸肌/球部肌肉受累为主患者所占比率最高(28. 8%vs 43. 5%vs 63. 6%,P 0. 05),早发AchR抗体阳性全身型MG被检肌肉RNS均为阳性患者所占比率最高(44. 2%vs 17. 4%vs 22. 7%,P 0. 05),QMGs与RNS最大波幅下降比率、RNS总波幅下降比率呈明显正相关关系(P 0. 01); MuSK抗体阳性全身型MG,其中重度受累患者所占比率、呼吸肌/球部肌肉受累为主患者所占比率均较高(均为75%),而被检肌肉RNS均为阳性患者所占比率较低(0%)。结论 不同亚型全身型MG的人群分布、性别占比、主要受累肌肉、受累肌肉受累程度及分布范围均具有显著的差别,这在全身型MG的分型诊断方面具有很大的参考价值;其RNS结果与疾病严重程度具有高度相关性,提示RNS在全身型MG的病情评估方面具有重要临床价值。     

重症肌无力患者电生理检查的特点

目的分析重症肌无力(myasthenia gravis,MG)患者重复神经刺激(repetitive nerve stimulation,RNS)和针电极肌电图(needle electrode electromyography,NEMG)检查结果的特点,探求电生理检查结果对于MG诊断的临床意义。方法收集2009年²013年南京鼓楼医院神经科住院的50例MG患者的电生理资料进行分析研究。结果 50例MG患者中RNS检查结果阳性者40例(80%)。其中Ⅱ、Ⅲ和Ⅳ型阳性率较高,均超过90%;而Ⅰ型阳性率远低于其余3型,仅为40%,其差异有统计学意义(P<0.01)。对不同神经RNS结果进行分析发现,刺激腋神经、面神经和尺神经时RNS阳性率分别为:60%、58%和16%;腋神经、面神经阳性率远高于尺神经,其差异有统计学意义(P<0.01)。NEMG检查结果示,58%的患者呈肌源性损害表现,且随年龄增长,异常率升高。结论 RNS技术是诊断MG可靠的电生理方法,以面神经及近端腋神经异常率较高;MG患者容易出现肌源性损害,且与年龄有关,NEMG的使用有利于发现MG患者的肌源性损害,为临床诊断和治疗提供帮助。     

临床神经电生理学在重症肌无力诊断及研究中的应用

<正>重症肌无力(myasthenia gravis,MG)是主要累及骨骼肌突触后膜上的乙酰胆碱受体(AChR),并由相应抗体(AChRab)介导的自身免疫性疾病。由于神经-肌肉接头(NMJ)冲动传递发生障碍,从而导致肌无力。临床神经电生理技术的发展,特别是重复神经电刺激(repetitive nerve stimulation,RNS)、单纤维     

Trigeminal nerve repetitive stimulation in myasthenia gravis

The aim of this study was to evaluate the utility of repetitive nerve stimulation (RNS) of the trigeminal nerve in assessing patients with myasthenia gravis (MG). In 26 normal controls and 21 patients with myasthenia gravis (MG), 2-Hz repetitive stimulation of the trigeminal nerve was performed using a monopolar needle for percutaneous nerve stimulation and recording over the surface of the masseter. In the MG patients, repetitive stimulation of the ulnar, spinal accessory, and facial nerves was also performed. The mean percent decrement in the compound muscle action potential (CMAP) amplitude among the different nerves at rest were: ulnar, 4.3%; spinal accessory, 10.1%; facial, 14%; and trigeminal, 17.3%. The facial nerve demonstrated abnormal decrement in 57% of all patients, compared with the spinal accessory (48%), trigeminal (43%), and ulnar (20%) nerves. All patients tolerated trigeminal RNS better than or as well as facial RNS. The study demonstrates that trigeminal RNS is a safe, reliable, efficient, and well-tolerated technique that provides another cranial nerve-muscle combination that can be used to supplement repetitive stimulation of other limb or cranial nerves in the evaluation of patients with bulbar or generalized MG.     

重症肌无力患者临床绝对评分和电生理检查的相关性研究

目的研究重症肌无力(MG)患者临床绝对评分和电生理检查结果的相关性。方法61例MG患者在进行临床绝对评分之后依次进行桡、腋、副和面神经低频重复电刺激(RNS)和伸指总肌单纤维肌电图(SFEMG)检查。通过SPSS10．0软件分析临床绝对评分与RNS和SFEMG结果的相关性。结果临床绝对评分与桡、腋、副和面神经低频RNS的波幅衰减程度之间均呈显著正相关；临床绝对评分与SFEMG结果中的平均jitter值、异常电位对比例和阻滞电位对比例之间呈非常显著正相关，而与正常电位对比例之间呈非常显著负相关。结论临床绝对评分的高低与电生理的检查结果间有很好的一致性，能够比较准确、客观地反映MG病情的严重程度。     

The accessory nerve repetitive nerve stimulation test: a valuable second-line test in myasthenia gravis

The diagnostic usefulness of the accessory nerve repetitive nerve stimulation (RNS) test was evaluated in 100 patients with myasthenia gravis (MG). The test was easy to perform and reliable at the low rates of stimulation. A higher diagnostic sensitivity was found in the accessory nerve RNS test than in the ulnar nerve RNS test on either the abductor digiti quinti or flexor carpi ulnaris muscles, especially in mild generalized MG. Diagnostic sensitivity was significantly increased when RNS test results for three muscles were combined, especially in mild generalized MG and sero-positive MG. In a small number of cases only the ulnar or accessory nerve RNS test was abnormal. There was a good correlation between electrophysiological and clinical severity of MG in the accessory nerve RNS test Thus, we conclude that the accessory nerve RNS test is a valuable second-line test and its greatest usefulness is in cases of mild generalized MG.     

Radial nerve repetitive stimulation in myasthenia gravis

The purpose of this study was to compare the diagnostic yield of repetitive radial nerve stimulation (RNS) while recording from extensor indicis proprius (EIP) to other commonly used muscle-nerve combinations in patients with myasthenia gravis (MG). Radial RNS with recording from EIP was performed in 20 controls and 20 patients with MG. It revealed an abnormal decrement at rest in 35% of patients compared to 11% with ulnar nerve stimulation, 64% with spinal accessory nerve stimulation, and 74% with facial nerve stimulation. Radial-EIP RNS is a reliable technique in the evaluation of MG and appears more sensitive than ulnar nerve RNS.     

Repetitive phrenic nerve stimulation in myasthenia gravis.

OBJECTIVE: In patients with MG it may be difficult to determine whether respiratory insufficiency is due to a defect in neuromuscular transmission. We therefore studied the clinical value of repetitive electrical stimulation of the phrenic nerve. METHODS: Repetitive phrenic nerve stimulation at 3 Hz was performed in 25 patients with MG. We recorded from the ipsilateral hemidiaphragm with surface electrodes before and after exercising the diaphragm for 10 and 90 seconds. The percent decrement of the negative peak (NP) area between the first and the fifth or sixth diaphragmatic compound muscle action potential (DCMAP) was analyzed and results compared with those from 10 healthy individuals. RESULTS: The mean +/- standard deviation percent change of the NP area in healthy individuals was -2.1 +/- 4.2%, with a normal cutoff of > or = 11%. Twelve patients (48%) had an abnormal decrement of DCMAP--9 had a decrement when the diaphragm was rested, 3 only after fatiguing of the diaphragm. The mean percent change in the 12 patients was 20% at rest, -18% after 10 seconds of exercise, and -23% after 90 seconds of exercise-a pattern consistent with MG. Repetitive stimulation of the accessory nerve with recording of the trapezius CMAP (TCMAP) was abnormal in nine patients (36%). The three patients with abnormal decrement of the DCMAP despite normal TCMAP had symptoms of dyspnea. CONCLUSIONS: Repetitive phrenic nerve stimulation studies are a promising tool in the diagnosis of respiratory muscle weakness in MG and should be part of electrophysiologic studies in patients with undiagnosed respiratory failure.     

Phrenic nerve studies predict survival in amyotrophic lateral sclerosis

Objective

Amyotrophic lateral sclerosis (ALS) is a severe neurodegenerative disease associated with short survival due to respiratory failure. We aimed to test the predictive value of the phrenic nerve motor response for survival, in a large population of ALS patients.

Methods

We included 254 ALS patients followed in our tertiary centre from 1997 to 2006, in whom phrenic nerve stimulation was performed according to the study inclusion and exclusion criteria. ALS was spinal onset in 175 and bulbar onset in 79 patients. The following features were recorded at entry: gender, age at presentation, onset region, diagnostic delay, forced vital capacity (FVC), ALS functional rating scale (ALS-FRS) including the respiratory subscore of the reviewed ALS-FRS and mean amplitude of motor responses by phrenic nerve stimulation (PhrenAmpl).

Results

Survival analysis was evaluated by Kaplan–Meier log-rank test and multivariate Cox proportional hazards. Independent factors negatively affecting survival were bulbar onset, short diagnostic delay, FVC and small PhrenAmpl for the total population. Small PhrenAmpl and short diagnostic delay were also independent factors for both spinal and bulbar-onset patients; age at onset and FVC were also independent predictors in bulbar-onset patients.

Conclusion

Phrenic nerve stimulation is a non-volitional test that can be performed quickly in most patients; it is a powerful predictor of survival in ALS.

Significance

Phrenic nerve stimulation should be considered as an additional test for respiratory assessment in ALS.     

Sensitivity of repetitive facial-nerve stimulation in patients with myasthenia gravis

Repetitive stimulation of the facial nerve is commonly performed in cases of suspected myasthenia gravis (MG) because bulbar weakness is often present, but the most sensitive facial muscle is unknown. We compared the sensitivity of repetitive nerve stimulation (RNS) to the frontalis and nasalis muscles in 244 patients with suspected MG. We found no difference in sensitivity of RNS when recording from these muscles in both ocular and generalized MG. In addition, we confirmed the low sensitivity of RNS for ocular (18%) or generalized (47%) MG. The specificity of facial RNS for both muscles was 100% and, in certain circumstances, may obviate the need for further diagnostic testing.     

REPETITIVE PHRENIC NERVE STIMULATION: USEFULNESS IN DIAGNOSTIC WORK-UP OF MIASTENIA GRAVIS (MG)

Cocito D., Isoardo G., Ciaramitaro P., Proto G., Testa M., Durelli L., Bergamasco B.
Dipartimento di Neuroscienze, Università di Torino
OBJECT : To evaluate sensitivity and specificity of repetitive nerve stimulation on diaphragm muscle stimulating phrenic nerve (RNS-DIAP) for diagnosis of MG, in comparison with RNS on abductor digiti minimi stimulating ulnar nerve (RNS-ADM) and on deltoid muscle stimulating axillary nerve (RNS-DELT). PATIENTS AND METHODS : We performed RNS-DIAP, RNS-DELT and RNS-ADM in 12 MG patients (9 women, 3 men, mean age: 55 ± 19 years) and 12 healthy controls (4 women, 8 men, mean age: 33 ± 14). RESULTS : Only 2 of 12 MG patients had positive RNS-ADM (-10% change in M-response area at fifth response), 11 had positive RNS-DELT and 12 had positive RNS-DIAP. Mean decrease in CMAP area was 8 ± 9% in RNS-ADM, 27 ± 13% in RNS-DELT and 31 ± 10% in RNS-DIAP. Difference between decrease in CMAP area was significant only between RNS-DIAP and RNS-ADM (p=0.002) and between RNS-DELT and RNS-ADM (p=0.0003). There was a weak correlation between clinical MG score and decrease in CMAP area in RNS-DIAP, however, 3 of 12 positive patients developed respiratory failure a few days after the test. DISCUSSION : In our hands, RNS-DIAP has no significant advantage as compared to RNSW-DELT in terms of sensitivity and specificity for MG diagnosis. Furthermore, this test was not well tolerated by the vast majority of patients.     

Effect of the combination of high-frequency repetitive magnetic stimulation and neurotropin on injured sciatic nerve regeneration in rats

Repetitive magnetic stimulation is effective for treating posttraumatic neuropathies following spinal or axonal injury.Neurotropin is a potential treatment for nerve injuries like demyelinating diseases.This study sought to observe the effects of high-frequency repetitive magnetic stimulation,neurotropin and their combined use in the treatment of peripheral nerve injury in 32 adult male Sprague-Dawley rats.To create a sciatic nerve injury model,a 10 mm-nerve segment of the left sciatic nerve was cut and rotated through 180°and each end restored continuously with interrupted sutures.The rats were randomly divided into four groups.The control group received only a reversed autograft in the left sciatic nerve with no treatment.In the high-frequency repetitive magnetic stimulation group,peripheral high-frequency repetitive magnetic stimulation treatment(20 Hz,20 min/d)was delivered for 10 consecutive days after auto-grafting.In the neurotropin group,neurotropin therapy(0.96 NU/kg per day)was administrated for 10 consecutive days after surgery.In the combined group,the combination of peripheral high-frequency repetitive magnetic stimulation(20 Hz,20 min/d)and neurotropin(0.96 NU/kg per day)was given for 10 consecutive days after the operation.The Basso-Beattie-Bresnahan locomotor rating scale was used to assess the behavioral recovery of the injured nerve.The sciatic functional index was used to evaluate the recovery of motor functions.Toluidine blue staining was performed to determine the number of myelinated fibers in the distal and proximal grafts.Immunohistochemistry staining was used to detect the length of axons marked by neurofilament 200.Our results reveal that the Basso-Beattie-Bresnahan locomotor rating scale scores,sciatic functional index,the number of myelinated fibers in distal and proximal grafts were higher and axon lengths were longer in the high-frequency repetitive magnetic stimulation,neurotropin and combined groups compared with the control group.These measures were not significantly different among the high-frequency repetitive magnetic stimulation,neurotropin and combined groups.Therefore,our results suggest that peripheral high-frequency repetitive magnetic stimulation or neurotropin can promote the repair of injured sciatic nerves,but their combined use seems to offer no significant advantage.This study was approved by the Animal Ethics Committee of the Affiliated Changzhou No.2 People’s Hospital of Nanjing Medical University,China on December 23,2014(approval No.2014keyan002-01).