1～14岁正常儿童胫后神经体感诱发电位正常值及其特点

目的：探讨正常儿童胫后神经（PTN）体感诱发电位（SEP）的特点及正常值。方法：对121名正常儿童进行PTN—SEP检测,分析各波的特点及各波参数随年龄变化规律。结果：PTN—SEP随年龄增长,波幅增高,使波容易辨认,波幅在个体问变异较大。左右双侧对应波的潜伏期（PL）和峰间期（IPL）比较差异无显著意义（P〉0．05）,各组男女间PL和IPL无性别差异（P〉0．05）。外周神经电位的腰髓电位（LP）、马尾电位（cE）、胭窝电位（PF）等3个波的潜伏期随年龄增长PI。延长,而P40和N45等皮层电位的PL在8岁前变化则不明显（相邻组间P〉0．05）,8岁后延长明显。PF-T12的IPL也随年龄增长而延长（相邻组间P〈0．05）;而T12-P40IPL3岁组较1岁组延长,但差异不明显,以后随年龄增长而缩短,6岁组达成人值。结论：儿童PTN—SEP的正常值按年龄组划分是完全必要的。由于各波PL受身长的影响大,因此绝对PL不宜作为PTN—SEP的异常标准。PTNSEP是评价小儿躯体感觉通路、脊髓、脑干和大脑功能的客观指标,具有较大的临床实用价值。     

股外侧皮神经损害患者的SEP检测

目的:观察股外侧皮神经(LFCN)损害患者的体感诱发电位(SEP)变化。方法:对35例 LCNT损害的患者进行SEP检测,并以健侧肢体作为对照组。结果:35例LFCN损害患者中异常29例 (82％),表现为P40或(和)P60潜伏期延长11例(37％)、波幅降低9例(31％),两者兼有7例(24％), P40、P60未引出2例(6％),与健侧肢体对照比较差异有显著意义。结论:LFCN受损后神经传导冲动 减弱,SEP潜伏期延长或(和)波幅降低,因而认为SEP是检测LFCN损害的一种敏感而有效的方法。     

经腹脊髓损伤后体感诱发电位变化的实验研究

目的：利用犬作经腹脊髓损伤在不同压强下观察体感诱发电位（SEP）的变化。方法：记录12只狗在不同的损伤强度（32、36、40kPa）下的脊髓诱发电位（SCEP）和皮层体感诱发电位（CSEP）,并比较了它们之间的改变。结果：狗的脊髓受压后SCEP和CSEP的波幅降低,潜伏期延长。其改变有显著性意义,而P波和N波之间改变无显著性差别。结论：对脊髓损伤的敏感性SCEP比CSEP相对较高,对脊髓损伤预后的评估CSEP比SCEP更有价值。     

诱发电位在Arnold-Chiari畸形合并脊髓空洞症中的应用

目的：探讨体感诱发电位（SEP）、运动诱发电位（MEP）与脑干听觉诱发电位（BAEP）在阿-基畸形（Arnold—Chiari malformation,ACM）合并脊髓空洞症（SM）手术疗效判定中的作用。方法：对ACM—SM患者行术前、术后上下肢SEP、MEP及BAEP检查,对比分析术前术后潜伏期、波幅及传导时间。结果：58例ACMSM患者,术前40例SEP异常,46例MEP异常,28例BAEP结果异常,表现为潜伏期延长、波幅降低及MEP的中枢传导时间（CMCT）延长。行后颅窝减压术＋硬脑膜扩大成形术＋后颅窝重建术后患者症状改善,复查MRI示小脑扁桃体回缩、空洞缩小;39例SEP、45例MEP及27例BAEP潜伏期、CMCT延长与波幅降低均有不同程度改善,SEP、MEP、BAEP分别各有1例与术前比较无明显改变。结论：SEP、MEP、BAEP可以作为评价ACM—sM手术前后效果判定的客观指标。     

帕金森病患者正中神经和胫神经体感诱发电位研究

目的:同时观察帕金森病患者正中神经和胫神经体感诱发电位的异常并推测其发生机制。方法:选择30名帕金森病患者和20名健康对照者,刺激正中神经,记录顶叶体感诱发电位的N20、P25、N30波,额叶的P20、N30波的潜伏期和波幅。刺激胫神经,记录顶叶体感诱发电位的P40、N50、P60波的潜伏期和波幅。结果:帕金森病患者上肢额叶N30和下肢N50波幅明显降低(P<0·05)。结论:帕金森病患者上下肢SEP同时出现异常是黑质纹状体系统多巴胺缺乏的结果,下肢N50波幅比上肢N30与临床症状的严重性更有相关性。     

重症肌无力20例患者VEP、SEP、BAEP的变化及临床意义

目的:比较重症肌无力(MG)患者模式翻转视觉诱发电位(VEP)、体感诱发电位(SEP) 及脑干听觉诱发电位(BAEP)3种诱发电位的变化。方法:测定20例新诊断的MG患者和50例正常人的VEP、SEP及BAEP。结果:与正常人比较,VEP 6例(30％)异常,其中5例双侧和1例单侧P100潜伏期延长,波幅降低;SEP 4例(20％)异常,其中3例双侧和1例单侧N13-N20波间期延长,波幅降低; BAEP 9例(45％)异常,其中7例双侧和2例单侧的Ⅲ-Ⅴ和Ⅰ-Ⅴ波间期延长,Ⅲ、Ⅴ波波幅减低。结论:有部分MG患者的VEP、SEP及BAEP有明显的变化,提示他们可能存在中枢神经系统胆碱能通路不同程度受损害,并且这三种诱发电位可能对胆碱能传递受损程度的判断有临床价值。     

肝硬化失代偿期病人体感诱发电位观察

目的 :探讨肝硬化失代偿期病人的神经功能状态。方法 :对 30例肝硬化失代偿期病人进行体感诱发电位 (SEP)检查 ,刺激部位均为右腕正中神经。结果 :肝硬化失代偿期病人的SEP有着不同程度的改变 ,其中P15、N2 0 、P2 5、N3 5的潜伏期延长和N13 -P15的波间期延长分别占本组异常数的 85 %、40 %、35 %、2 5 %和 2 0 %。这些值与正常人组相比较 ,其两组间差异均有极显著性意义 (P <0 0 1)。结论 :SEP可为研究亚临床肝性脑病提供电生理学的客观依据。     

体感诱发电位和脑电图对非外伤性昏迷患儿预后的判断价值

目的：探讨体感诱发电位（SEP）和脑电图（EEG）检测在非外伤性昏迷患儿预后评估中的价值。方法：对26例昏迷患儿[格拉斯哥昏迷量表（GCS）评分≤8分]早期进行双侧正中神经的SEP检测和EEG检查，随访6个月后进行预后分析。结果：①26例昏迷患儿SEP11例正常，15例（58％）异常，SEP的异常均表现为皮层电位N20异常，其中6例皮层N20波缺失；26例患儿EEG结果均为异常，其中5例为背景活动低电压，1例为弥慢性0活动，20例为弥漫性8慢活动；②SEP正常的11例中，9例预后良好，2例（18％）预后不良，SEP异常的15例中，14例（93％）预后不良，其中6例死亡，5例EEG为背景活动低电压患儿的SEP均严重异常，预后最差。结论：①早期对非外伤性昏迷患儿的预后判断SEP优于EEC；②SEP皮层电位N20波缺失，同时EEG为背景活动低电压患儿，预后最差；③SEP对非外伤性昏迷患儿在早期判断预后是一种客观、有效方法，有着重要的临床应用价值。     

高颅压患者的体感诱发电位表现

目的：观察颅内压（ICP）增高对体感诱发电位（SEP）的影响。方法：对86例颅内病变引起的高颅压病人治疗前后进行体感诱发电位检测。同时测定患者脑压及血压。结果：ICP升高时SEP各波潜伏期延长，波幅降低，以N20波最明显，呈高度负相关，结论：SEP参数改变可间接推断ICP变化，并有助于病情及预后的判断。     

1～14岁儿童正中神经及胫后神经体感诱发电位正常参考值

目的：测量正常儿童正中神经体感诱发电位(MN—SEP)及胫后神经体感诱发电位(PIN—SEP)，探讨儿童SEP正常值。方法：1～14岁正常儿童390名，分13组，每岁为一组，均行双侧正中神经体感诱发电位及胫后神经体感诱发电位检测，取单肢结果统计学处理。结果：儿童SEP波潜伏期随年龄增长先缩短后延长，但不同部位的电位表现并不一致。峰问期没有年龄规律。结论：严密的正常参考值是正确分析儿童SEP结果的有效保证。     

椎基底动脉供血不足家兔模型体感诱发电位分析

目的：研究椎基底动脉供血不足(VBI)时体感诱发电位(SEP)的动态变化及其诊断意义。方法：选择成年家兔10只，通过结扎家兔一侧椎动脉人为造成VBI模型，以N27、P40峰潜期及峰间期为指数，动态检测其右侧胫后神经SEP的变化，研究其变化规律。结果：VBI后SEPN27，p40的峰潜伏期明显延长，峰间期无明显变化。结论：SEP对VBI发作期感觉功能的变化有诊断价值，并可评价发作的严重程度。     

65例颈椎型脊髓病体感诱发电位分析

目的研究颈椎型脊髓病皮质体感诱发电位（ＳＥＰ）变化。方法对６５例颈椎型脊髓病患者和２６例正常人进行正中神经和胫后神经刺激的ＳＥＰ对照研究，并对１０例患者作治疗前后对照观察。结果本组异常率为４５％，主要表现为各波替伏期和波间期（Ｎ２０—Ｐ２５，Ｐ２５—Ｎ３５，Ｐ４０—Ｎ４５）延长，且下肢的延长更加明显，部分患者出现波形分化不良。经保守治疗后６例正常，２例好转，且ＳＥＰ的好转先于临床的改善。结论ＳＥＰ对评判颈椎型脊髓病的脊髓传导功能具有重要的意义，且有助于临床预后的评价。     

痉挛性斜颈体感诱发电位的研究

目的：探讨痉挛性斜颈患者大脑皮层功能的变化。方法：对30例痉挛性斜颈患者刺激正中神经后体感诱发电位（SEP）的P22、N30波潜伏期及P22、N30波幅进行比较分析,30例正常对照组仅在颈部主动向右侧扭转时对双侧P22、N30波幅进行比较分析。结果：病例组SEPP22、N30潜伏期正常,双侧比较差异无统计学意义,头部扭转方向的对侧大脑半球前中央区的P22-N30波幅比明显高于对侧,差异有统计学意义。正常对照组前中央区记录的双侧P22N30波幅比较差异无统计学意义。结论：SEP P22、N30潜伏期正常提示传导通路结构完整,头部扭转方向的对侧大脑半球前中央区的P22-N30波幅比明显高于对侧,提示患者对侧大脑皮层前中央区电活动存在异常的兴奋及抑制,即抑制性减弱,兴奋性增高,N30记录的是刺激正中神经SEP中长潜伏成分,可能来源于运动辅助区,进一步提示患者存在感觉一运动整合功能异常。     

Developmental and Individual Differences on the P1 and N170 ERP Components in Children With and Without Autism

The P1 and N170 components, two event-related potentials sensitive to face processing, were examined in response to faces and vehicles for children with autism and typical development. P1 amplitude decreased, P1 latency decreased, and N170 amplitude became more negative with age. Children with typical development had larger P1 amplitudes for inverted faces than upright faces, but children with autism did not show this pattern. Children with autism had longer N170 latencies than children with typical development. Smaller P1 amplitudes and more negative N170 amplitudes for upright faces were associated with better social skills for children with typical development.     

Developmental and individual differences on the P1 and N170 ERP components in children with and without autism

The P1 and N170 components, two event-related potentials sensitive to face processing, were examined in response to faces and vehicles for children with autism and typical development. P1 amplitude decreased, P1 latency decreased, and N170 amplitude became more negative with age. Children with typical development had larger P1 amplitudes for inverted faces than upright faces, but children with autism did not show this pattern. Children with autism had longer N170 latencies than children with typical development. Smaller P1 amplitudes and more negative N170 amplitudes for upright faces were associated with better social skills for children with typical development.     

儿童孤独症患儿脑电图特征分析

目的：通过观察和分析儿童孤独症患儿脑电图（EEG）改变,探讨脑电图检查对儿童孤独症的诊断意义。方法：对115例儿童孤独症患儿的脑电图检查结果进行分析。结果：115例患儿,异常脑电图52例,异常率45．2％。轻度异常23例,表现为基本节律减慢,慢波多于同龄;中度和重度异常29例,其中局限行异常14例,出现痫样放电10例,局限性异常＋痫样放电5例。结论：EEG客观反映了儿童孤独症患儿的脑功能情况,对儿童孤独症有诊断价值     

The effect of changing stimulus intensities on median nerve somatosensory-evoked potentials

We investigated median nerve somatosensory-evoked potentials (SEP) in 31 healthy volunteers to test the hypothesis that 1) increasing stimulus intensity influences SEP components in both amplitude and latency 2) SEP components respond differently to changing intensities. Cluster analysis and analysis of variance were used for statistical testing. Three groups of components could be found according to latency changes in response to increasing stimulus intensities: N13, and P15, the primary cortical response (N19, P22) and the components over 30 ms. In general, SEP components below 30 ms significantly shortened in latency and increased in amplitude with subsequent saturation. In contrast, in components over 30 ms latencies decreased linearly and amplitudes changed inhomogeneously. The clear effect of stimulus intensity on most median nerve SEP components makes it necessary to maintain comparable stimulus intensities when comparing intra- and interindividual registrations.     

Do children born after assisted conception have less risk of developing infantile autism?

BACKGROUND: A Danish population based matched case-control study of perinatal risk factors in children with infantile autism has provided some interesting and surprising observations regarding infantile autism and children born after assisted conception. METHODS AND RESULTS: The cases (461) consisted of all children born between 1990 and 1999 and diagnosed with infantile autism in the Danish Psychiatric Central Register before February 2001. Matched controls were identified in the Danish Civil Registration System. The main exposure measures included obstetric risk factors for infantile autism. We found a 59% decreased risk for developing infantile autism among children conceived after assisted conception (odds ratio [OR] 0.41, 95% [0.19-0.89]) and a 63% decreased risk after adjusting for known risk factors for assisted conception and infantile autism (OR 0.37, 95% [0.14-0.98]). CONCLUSION: We found that children born after assisted conception had a lower risk of developing infantile autism then their matched controls. Our observations could possibly be explained by the mother's health status before and during early pregnancy. Our findings require further investigation in larger studies.