兔坐骨神经急性挤压伤的MRI与病理学对比初步研究

目的模拟人类外周神经损伤机制,制作坐骨神经急性挤压伤模型,探讨其MRI表现与病理学之间的关系,为临床诊治外周神经损伤及选择手术时机提供客观依据.方法 32只新西兰兔按钳夹力的不同随机分为A、B 2组,钳夹力分别为3.61、10.50 kg,每组有16只,左下肢为损伤侧,右下肢为对照侧,建立坐骨神经急性挤压伤模型,每组又将4只分在1、2、4、8周的不同时间观察段中,于伤后不同时间段分别行双侧坐骨神经MR扫描,扫描后分别取材进行病理学检查.结果损伤侧坐骨神经除T1W1上无明显变化外,三维T2WI、T2WI的质子频谱预饱和反转恢复序列(SPIR)、平衡快速梯度回波序列(B-FFE)、T2WI的短反转时间恢复序列(STIR)均显示挤压伤远段神经增粗、扭曲、T2WI信号增高.32条损伤神经30条MRI显示异常,诊断正确率93.75%,假阴性率为6.25%.损伤侧远段神经/肌肉信号强度比(SIR)明显高于对照侧远段(P<0.001); A、B 2组间SIR差异无显著意义 (P>0.05).损伤侧SIR 1周明显升高,展趾功能丧失,2周SIR达高峰,病理学检查见髓鞘大部分崩解、轴突消失;4～8周SIR下降,病理见大量雪旺细胞明显增生,髓鞘崩解产物吸收,此时展趾功能逐渐恢复.对照侧坐骨神经MRI及病理学检查未见异常.结论 MRI能诊断坐骨神经损伤,SIR动态测量能无创地反映神经损伤后病理学上神经功能逐渐修复的过程,可作为检测神经损伤退变和修复及评估预后的有效检查方法.     

前交叉韧带损伤MRI诊断假阳性和假阴性分析

目的 探讨MRI对前交叉韧带损伤诊断的假阳性及假阴性,提高MRI诊断水平.方法 回顾性分析68例(72膝)膝关节外伤后临床怀疑前交叉韧带损伤患者的MRI检查结果,并与关节镜检查结果 进行对照分析.结果 本组68例(72膝)膝关节外伤患者中,以关节镜结果 为标准,MRI诊断结果:真阳性数52例,真阴性数13例,假阳性数5例,假阴性数2例.灵敏度、特异度、假阳性率及假阴性率分别为96.3%,72.2%,6.9%,2.8%,诊断正确率90.3%.结论 MRI是诊断前交叉韧带损伤极有价值的无创方法,但存在一定的假阳性和假阴性,需要结合患者临床病史和更细致的MRI分析.     

前交叉韧带损伤的MRI诊断与临床诊断比较研究

目的:探讨核磁共振(MRI)和临床检查对急性前交叉韧带(anterior cruciate ligament,ACL)损伤诊断的价值.方法:自2000年9月～2003年12月,对76例急性创伤性膝关节血肿病例进行前抽屉试验、Lachman试验两项临床检查和MRI检查,后进行关节镜手术检查.所有病例平均年龄28.0±7.9岁,关节镜手术距受伤时间平均为5.0±1.4天,其中男性58例,女性18例;左膝损伤25例,右膝损伤51例,运动损伤32例,交通伤25例,滑倒扭伤、摔伤19例.所有病例伤后8小时内均出现膝关节肿胀、疼痛、活动受限.以关节镜检查结果为标准,对临床检查和MRI检查诊断ACL损伤的结果进行比较.结果:关节镜检查发现ACL损伤52例,正常24例.前抽屉试验、Lachman试验两项临床检查共诊断出ACL损伤31例,正常45例;MRI检查共诊断出ACL损伤51例,正常25例.以关节镜检查为标准,临床检查诊断结果:真阳性数28例,真阴性数24例,假阳性数3例,假阴性数21例,准确度、敏感度、特异度分别为68.4%、57.1%、88.9%;MRI诊断结果:真阳性数49例,真阴性数22例,假阳性数2例,假阴性数3例,准确度、敏感度、特异度分别为93.4%、94.2%、91.7%.MRI诊断急性ACL损伤的准确度显著高于临床检查(P＜0.01).结论:临床检查诊断急性前交叉韧带损伤的假阴性率较高,MRI是早期诊断急性前交叉韧带损伤的有效方法.     

大鼠脊髓半切块状缺损模型的建立及科学性评估

目的建立脊髓损伤的半切模型,为科学评价移植物治疗脊髓损伤提供模型。方法通过自行研制的脊髓半切切割刀,半切大鼠腰膨大,形成相同大小的块状缺损,建立半切块状缺损模型,通过BBB评分、运动诱发电位及体感诱发电位检测来综合评价模型的科学性和稳定性。结果该模型可形成相同大小的块状缺损,伤侧后肢术后1天BBB运动功能评分为(0.50±0.53)分,术后84天为(3.63±0.74)分;术后28天伤侧N1波峰潜时MEP为(30.25±3.04)m s、皮层感觉诱发电位(SEP)为(24.03±3.64)m s,较正常组均有显著延长。结论该脊髓块状缺损模型具可靠性和稳定性,适用于评价移植物治疗脊髓损伤。     

MRI和MR关节造影在肩部损伤中的诊断价值

目的 :探讨MRI(核磁共振成像 )和MR关节造影在肩部损伤中的诊断价值。方法 :自 1999年 3月至 1999年11月 ,共有 73个患者 75例肩关节接受了肩部MRI检查 ,其中 16例经关节镜或手术证实。对手术中所见与核磁共振表现进行比较。结果 :对肩袖完全撕裂 ,MRI和MR关节造影对全层撕裂诊断阳性率分别为 90 .6 %和 10 0 % ,特异性分别为 96 %和 97.6 %。MRI对肩袖部分撕裂诊断正确率低 ,可靠性差 ;MR关节造影诊断正确率达 80 % ,是肩袖部分撕裂诊断的可靠方法。MRI对急性Bankart损伤诊断阳性率 10 0 % ,对慢性或陈旧损伤 ,阳性率低 ,只有 33.3% ;而MR关节造影对慢性或陈旧损伤诊断阳性率达 10 0 %。对SLAP损伤 ,MR关节造影较MRI诊断阳性率高 ,但目前关节镜仍是SLAP损伤更可靠的定性诊断手段。     

椎旁定位腰骶体感诱发电位在腰椎间盘突出症中的诊断作用

目的探讨椎旁定位腰骶体感诱发电位（LSSEP）在腰椎间盘突出症中的诊断作用.方法对54例有L4、L5和S1神经根损害表现的腰椎间盘突出症患者进行胫后神经体感诱发电位（SEP）、皮节体感诱发电位（DSEP）和椎旁定位LSSEP检查,测定其P40的潜伏期.结果胫后神经SEP检测异常率为40.74%,其中多水平突出的异常率明显高于单水平突出者（P＜0.01）;L5S1 DSEP异常率为87.04%,明显高于胫后神经SEP异常率（P＜0.01）;椎旁定位LSSEP异常率为96.30%,显著高于胫后神经SEP和DSEP异常率（P＜0.01）.在L3～4椎间盘突出中,以L4 LSSEP异常为主,L4～5椎间盘突出中,以L5 LSSEP异常为主.结论椎旁定位LSSEP是诊断腰椎间盘突出症快捷、可靠、敏感的检测方法,其结果与神经根受累水平相一致,对多水平突出手术入路的定位较为准确.     

高频超声对兔坐骨神经急性挤压伤的观察

目的：运用高频超声观察兔坐骨神经急性挤压伤，探讨其临床诊断价值。方法：按观察时间的不同将16只健康家兔随机分为4组。建立兔坐骨神经急性挤压伤模型，损伤后第1、2、4、8周，分别应用高频超声在同一水平上观察双侧坐骨神经的变化。结果：坐骨神经挤压伤后，其声像图和内径均有变化，且与神经损伤后退变、再生及肢体功能的动态变化相一致。结论：高频超声可直观地反映神经退变和再生的过程，提供了诊断外周神经损伤的新方法，对临床判断和预后提供客观依据。     

膝关节半月板撕裂磁共振成像与关节镜对照研究

目的分析磁共振成像（MRI）在膝关节半月板撕裂诊断中的价值。方法分析168例（共计336个半月板）临床疑诊半月板损伤患者,依次在1周内行磁共振（MR）和关节镜检查,对比MR和关节镜检查结果,探讨MRI对膝关节半月板撕裂诊断符合率。结果以关节镜为参考标准,168例（共计336个半月板）中MRI诊断半月板撕裂敏感性96．9％,特异性为87．5％,准确性为92．5％,假阳性率为12．5％,假阴性率3．1％,MRI具有术前诊断价值。结论MRI诊断半月板撕裂具有很高准确性,但仍有一定的假阳性与假阴性。     

MRI对膝关节前交叉韧带损伤诊断的假阳性及假阴性的病例分析

目的探讨MRI诊断出现假阳性及假阴性的影响因素,进一步分析提高MRI诊断准确率的诊断要点。方法以关节镜结果作为诊断标准,回顾性分析162例膝关节前交叉韧带损伤患者的MRI诊断结果。结果 162例患者中有12例患者的MRI诊断结果与关节镜不符,假阳性率为3.09%,假阴性率为4.32%。结论充分认识MRI诊断ACL损伤的假阳性和假阴性的相关影响因素,积极采用提高膝关节前交叉韧带诊断准确率的技术方案,才能更好的体现MRI对ACL的诊断价值。     

高压氧治疗对中重型颅脑损伤患者脑干和体感诱发电位的影响及疗效分析

目的 观察高压氧(hyperbaric oxygen,HBO)治疗对外伤性中重型颅脑损伤患者脑干听觉诱发电位(bralnstem auditory evoked potential,BAEP)、体感诱发电位(somatic evoked potential,SEP)的影响及其治疗效果.方法 134例外伤性中重型颅脑损伤患者分为对照组67例和HBO治疗组67例.对照组采用必要的神经外科处理及常规药物治疗;HBO组在对照组治疗的基础上,病情稳定后加用3个疗程的HBO治疗.治疗前后行BAEP、SEP检查及格拉斯哥昏迷评分(GCS),伤后6个月随访行格拉斯哥预后评分(GOS).结果 治疗前2组患者BAEP、SEP异常率及GCS评分差异无统计学意义(P>0.05);治疗后对照组BAEP明显改善(P<0.05),SEP改善更为显著(P<0.01),GCS评分明显升高(P<0.05),HBO组BAEP、SEP改善均有统计学意义(P<0.01),GCS评分提高有统计学意义(P<0.01);治疗后HBO组BAEP、SEP异常率与对照组比较差异有统计学意义(P<0.01),GCS评分与对照组比较差异有统计学意义(P<0.05);伤后6个月GOS评分显示HBO组预后良好患者较对照组明显增多(P<0.01),死亡率则明显降低(P<0.05).结论 HBO可明显改善中重型颅脑损伤患者BAEP及SEP的异常情况,提高临床疗效.     

Magnetic resonance imaging evaluation of acute crush injury of rabbit sciatic nerve: correlation with histology

OBJECTIVE: To investigate the relation between the quantitative assessment of magnetic resonance imaging (MRI) features and the correlation with histology and functional recovery by using the rabbit sciatic nerve crush model. METHODS: In New Zealand, 32 rabbits were randomly divided into 2 groups (group A and B); all rabbits underwent crushing injury of their left sciatic nerve. In group A (n = 16), the sciatic nerves were crushed by using microvessel clamps with a strength of 3.61 kg. In group B (n = 16), the sciatic nerves were crushed with a strength of 10.50 kg. Right sciatic nerves were served as controls. Serial MRI of both hind limbs in each rabbit was performed before and at the time point of 1, 2, 4, and 8 weeks after crushed injury. The MRI protocol included T1-weighted spin-echo (T1WI), 3 dimension turbo spin-echo T2-weighted (3DT2WI), T2-weighted turbo spin-echo images with spectral presaturation with inversion recovery (T2WI/SPIR), balanced fast-field echo (B-FFE) and short-time inversion recovery (STIR) sequences. The coronal image of the sciatic nerve was obtained. The nerve and muscle signal ratio (SIR) on each sequence was measured. The function recovery was observed and pathological examination was performed at each time point. RESULTS: A signal intensity increase of the distal segment of crushed sciatic nerves was found on 3DT2WI, T2WI/SPIR, B-FFE, and STIR, but not on T1WI images. Of 32 crushed nerves, 30 nerves showed high signal intensity. The correct diagnostic rate was 93.75% with false negative-positive of 6.25%. The SIR of the crushed sciatic nerve at distal portion was higher than those of the control nerves; there was a statistically significant difference (P < 0.001). The SIR of the distal portion of crushed nerves was higher than that of the proximal nerve portion; there was a statistically significant difference (P < 0.001). Whereas, the SIR at proximal nerve portions of crushed nerve was similar to control nerves (P > 0.05). The SIR between group A and group B was not found statistically significantly different (P > 0.05). The SIR of crushed nerves at distal portion increased at one week after the crush injury, subsequently further increased, and reached a maximum at 2 weeks. The pathological examination revealed myelin swelling and axonal fragmentation of crushed nerve. Abduction function of injured hind limb was deficit. From 4 to 8 weeks following the crush, the SIR decreased, correspondingly, nerve regeneration was revealed on pathology including extensive Schwann cells proliferation and the immature myelin formation. The abduction function gradually recovered. There was no abnormal finding on MRI for control and sham-operated nerves. CONCLUSION: The SIR of injured nerve at distal portion increased on MRI. The evolution of SIR after injury was correlated with the degeneration and regeneration of nerve and the function recovery of lower extremities. Assessment of peripheral nerve injury by using SIR could reveal acute nerve injury, as well as aid in monitoring the recovery process. The pathophysiological basis for the SIR is predominantly the results of axon breakdown and myelin regeneration     

蛇毒神经生长因子对大鼠坐骨神经损伤修复作用的实验研究

目的：研究外源性给予江浙蝮蛇毒提取的神经生长因子（sNGF)对大鼠坐骨神经损伤的修复作用。方法：建立大鼠坐骨神经钳夹模型，局部滴加药物和术后肌注sNGF，通过展爪反射，趾间距，自切及脊髓诱发电位（SEP），运动诱发电位（MEP）评定，观察坐骨神经修复情况。结果 sNGF治疗可使伤后SEP，MEP提早出现，减轻自切，改善后肢运动功能。结论：蛇毒提取的NGF对大鼠坐骨神经损伤修复具有促进作用。     

兔坐骨神经扩散张量纤维束示踪

目的:探讨DTI成像能否用于显示兔的坐骨神经.方法:三只成年家兔,运用3T磁共振扫描仪、8通道相控阵膝关节线圈和DTI成像方法扫描兔股部,后处理3D显示坐骨神经的走行.结果:运用DTI 3D纤维束成像显示了兔的坐骨神经,其路径与兔坐骨神经大体解剖部位一致.结论:DTI成像在动物周围神经的研究中有一定的应用前景.     

In vivo MRI monitoring nerve regeneration of acute peripheral nerve traction injury following mesenchymal stem cell transplantation

Objective

To assess the continuous process of nerve regeneration in acute peripheral nerve traction injury treated with mesenchymal stem cells (MSCs) transplantation using MRI.

Materials and methods

1 week after acute nerve traction injury was established in the sciatic nerve of 48 New Zealand white rabbits, 5 × 10⁵ MSCs and vehicle alone were grafted to the acutely distracted sciatic nerves each in 24 animals. Serial MRI and T1 and T2 measurements of the injured nerves were performed with a 1.5-T scanner and functional recovery was recorded over a 10-week follow-up period, with histological assessments performed at regular intervals.

Results

Compared with vehicle control, nerves grafted with MSCs had better functional recovery and showed improved nerve regeneration, with a sustained increase of T1 and T2 values during the phase of regeneration.

Conclusion

MRI could be used to monitor the enhanced nerve regeneration in acute peripheral nerve traction injury treated with MSC transplantation, reflected by a prolonged increase in T1 and T2 values of the injured nerves.     

原发输尿管癌影像诊断评价

目的 :回顾性评价常用影像学方法诊断原发输尿管癌的价值。材料和方法 :我院近 2 0年共手术治疗原发输尿管癌 10 3例。术前影像检查包括 :B超 ,静脉肾盂造影 ,逆行输尿管造影 ,CT和MRI。以手术所见和病理诊断为参照 ,对术前原始影像诊断报告进行比较分析 ;以原诊断报告描述管壁增厚、占位、充盈缺损 ,诊断意见提示肿瘤者视为准确。结果 :B超、静脉肾盂造影、逆行输尿管造影、CT和MRI的总体使用率分别为 95 %、63 %、3 4%、5 6%和 3 4% ,诊断符合率分别为 45 %、15 %、83 %、5 0 %和 89% ,假阴性率分别为 4%、2 %、3 %、7%和 2 %。结论 :B超的使用率最高 ,MRI的诊断符合率最高 ,两者结合可能是原发输尿管癌诊断的最佳影像组合。     

电磁场促进周围神经再生的组织学观察

目的:探讨电磁场对周围神经再生的作用。方法:以60只Wistar大白鼠左侧坐骨神经重度钳夹伤为模型,术后随机将大鼠均分为治疗组和对照组,治疗组给予锯齿波形电磁场治疗。术后不同时期对大鼠坐骨神经进行组织学检查。结果:电磁场治疗能促进周围神经损伤后的轴索和髓鞘再生。结论:电磁场治疗对周围神经再生确有促进作用;它可能是通过对周围神经再生过程中多环节的调控和促进,通过多种协同机制,促进周围神经再生和功能恢复的。     

周围神经离断后显微缝合生物膜性材料包裹的实验研究

本实验分别用自体静脉、自体筋膜、酒精人胎盘羊膜、蜂蜜人胎盘羊膜、蜂蜜人胎盘静脉包裹神经缝合处。术后进行大体观察、组织学检查和诱发电位检测。结果表明,自体生物膜性材料包裹神经缝合处,具有减轻其周围纤维组织增生的作用,尤其以自体筋膜效果较好。