基于纤维束空间统计分析多参数DTI在遗忘型轻度认知障碍的应用

目的:采用基于纤维束空间统计分析(TBSS)的方法分析遗忘型轻度认知障碍(aMCI)患者DTI多参数图,以研究其全脑白质纤维束损害的特点以及可能的病理机制。方法:选取29例aMCI患者和30名正常老年人(正常对照组),对全脑进行1.5T磁共振DTI序列扫描。采用FSL软件对被试的DTI扫描数据进行预处理后对aMCI组、正常对照组的部分各向异性、平均弥散、轴向弥散、径向弥散图进行基于体素的全脑非参数统计学比较。结果:与正常对照组比较,aMCI组的双侧皮质脊髓束、双侧扣带束中部、双侧胼胝体、左侧内囊前肢、左侧外囊、双侧下额枕束、左侧上纵束、左侧膝状体内视路、右侧钩束、右侧视放射出现FA值减低;胼胝体膝部及体部、左侧皮质脊髓束、左侧内囊前后肢、左侧外囊、左侧上纵束出现MD值增加;DR值增高的区域与FA值类似;DA图未发现异常;左侧白质改变多于右侧。aMCI组全脑白质各参数图与简易智能精神状态检查量表(MMSE)评分没有相关性。结论:相对于正常老年人,aMCI患者脑内多发纤维束出现损害,其DTI多参数图改变特点提示白质纤维束的损害可能主要是由退行性改变(retrogenesis)导致的。DTI各参数图的改变可能无法反映患者总体认知功能障碍的严重程度,但这还需要进一步的大样本研究。     

Application of TBSS-based multiple DTI index analysis in amnestic MCI

目的:采用基于纤维束空间统计分析(TBSS)的方法分析遗忘型轻度认知障碍(aMCI)患者DTI多参数图,以研究其全脑白质纤维束损害的特点以及可能的病理机制.方法:选取29例aMCI患者和30名正常老年人(正常对照组),对全脑进行1.5T磁共振DTI序列扫描.采用FSL软件对被试的DTI扫描数据进行预处理后对aMCI组、正常对照组的部分各向异性、平均弥散、轴向弥散、径向弥散图进行基于体素的全脑非参数统计学比较.结果:与正常对照组比较,aMCI组的双侧皮质脊髓束、双侧扣带束中部、双侧胼胝体、左侧内囊前肢、左侧外囊、双侧下额枕束、左侧上纵束、左侧膝状体内视路、右侧钩束、右侧视放射出现FA值减低;胼胝体膝部及体部、左侧皮质脊髓束、左侧内囊前后肢、左侧外囊、左侧上纵束出现MD值增加;DR值增高的区域与FA值类似;DA图未发现异常;左侧白质改变多于右侧.aMCI组全脑白质各参数图与简易智能精神状态检查量表(MMSE)评分没有相关性.结论:相对于正常老年人,aMCI患者脑内多发纤维束出现损害,其DTI多参数图改变特点提示白质纤维束的损害可能主要是由退行性改变(retrogenesis)导致的.DTI各参数图的改变可能无法反映患者总体认知功能障碍的严重程度,但这还需要进一步的大样本研究.     

基于TBSS的急性CO中毒患者脑白质微细结构损伤研究

目的应用扩散张量成像(DTI)观察急性CO中毒患者脑白质结构的改变,应用影像技术量化脑白质损害程度,推测急性CO中毒迟发性脑病相关机制。方法对25例急性CO中毒患者和25例性别与年龄相匹配的健康志愿者进行头部磁共振DTI扫描,采用基于纤维束示踪的空间统计方法(TBSS),分析急性CO中毒患者脑白质平均扩散系数(MD)、各向异性分数(FA)的变化,探讨其与患者认知功能障碍间的相关性。结果与健康对照组对比,急性CO中毒患者组的放射冠、胼胝体的MD增高而FA降低(P<0.05);双侧上纵束,内、外囊,丘脑和脑干的MD增加但无FA改变(P<0.05)。与临床量表分数相关性比较发现,差异脑区FA值与MMSE评分呈一定正相关(P<0.05),差异脑区MD值与MMSE评分呈一定负相关(P<0.05)。结论DTI准确反映急性CO中毒导致脑内白质广泛的血管源性水肿以及脑白质纤维束完整性损害,可能量化反应病情缺氧脑损伤程度、预测迟发性脑病,同时DTI参数的改变还可以一定程度反映患者认知障碍情况。     

遗忘型轻度认知障碍脑白质纤维束扩散张量成像研究

目的：使用3．0T 磁共振扩散张量成像（DTI）技术观察遗忘型轻度认知障碍（aMCI）患者脑白质纤维束的改变,探讨 DTI 对 aMCI 的临床诊断价值。方法：对16例 aMCI 患者和12例健康志愿者（对照组）行 DTI 扫描,测量两组受试者的胼胝体膝部、压部、双侧的内囊后肢、小脑中脚、上纵束、下纵束、下额枕束和扣带束的各向异性（FA）和表观扩散系数（ADC）值并进行统计学分析。结果：aMCI 组双侧下额枕束的 FA 值均较对照组低,右上纵束的 ADC 值较对照高,差异具有统计学意义（P ＜0．05）;其它部位白质纤维束的 FA 和 ADC 值在两组间的差异无统计学意义（P ＜0．05）。结论：aM-CI 患者的下额枕束和上纵束发生了微观结构的变化,可能在一定程度上参与了遗忘型轻度认知障碍的发生,DTI 对于aMCI 的诊断具有重要的临床价值。     

运动神经元病患者大脑结构异常评估:基于多模态成像

目的探究性利用多模态影像技术评估14例运动神经元病(MND)患者脑部灰白质结构改变,分析疾病表征及脑内异常的相关性。方法14例临床诊断考虑为MND患者作为实验组,认知功能评分正常,14例年龄、性别和左右利手匹配的无神经系统疾病的志愿者为对照组,行常规磁共振扫描以及T13D和DTI扫描。应用Freesurfer软件对T13D数据进行分析,组间比较全脑皮层厚度差异。应用基于纤维束示踪的空间统计方法(TBSS)和基于白质模板分割法分析DTI数据,比较全脑白质结构差异。显著差异白质结构特征值与临床指标作相关性分析。结果与对照组相比,Freesurfer结果显示MND患者右侧颞上回和左侧额中回下部局部局限性皮层厚度减低(P<0.05,非FDR校正)。TBSS结果表明胼胝体至运动皮层区域皮质脊髓束FA值和F1值呈显著性降低(P<0.05,FEW校正),而相应区域F2、L1、MD等值未见明显差异,特别是左侧上放射冠白质纤维,其FA值显著性降低(P=0.007),并与ALSFRs评分正相关(r^2=0.723,P=0.004)。结论无明显认知障碍MND患者主要表现为轻微灰质结构改变,白质结构特别是胼胝体至运动皮层的皮质脊髓束纤维结构完整性损伤,运动功能皮层信息上下传导受阻。上放射冠FA值与疾病严重程度相关,未来可用于监测疾病严重程度和发展进程。     

高原和平原地区健康成人脑白质扩散张量成像TBSS分析

目的 采用扩散张量成像(DTI)及基于纤维束追踪空间统计分析(TBSS)研究平原与高原健康成人的脑白质微细结构差异.方法 对16名高原健康成人和与之年龄、受教育程度相匹配的20名平原健康成人行DTI检查,应用TBSS方法分析两组受检者脑白质纤维DTI的相关参数:各向异性分数(FA)、轴向扩散系数(AD)、平行扩散系数(RD)、平均扩散系数(MD).对两组各项参数进行比较.结果 与平原组比较,高原组在胼胝体体部、胼胝体压部、胼胝体膝部、两侧上纵束、两侧上放射冠、右侧内囊前肢、内囊豆状核后肢、右侧丘脑辐射线(包括视辐射线)的AD值显著增高(P＜0.05,FWE校正);MD值显著升高的脑区是胼胝体体部、右侧上纵束、右侧上放射冠、右侧内囊前肢(P＜0.05,FWE校正);RD值显著升高的脑区是胼胝体体部、右侧上纵束.结论 通过DTI及TBSS分析,高原健康成人相对于平原健康成人脑白质纤维存在差异.     

基于扩散张量成像对颈椎源性疼痛患者脑白质微结构异常的研究

目的 采用基于纤维束的空间统计方法(TBSS)检测颈椎源性疼痛(CSP)患者的脑白质微结构异常。方法 对45例CSP患者(患者组)和45名性别、年龄匹配的健康志愿者(对照组)进行全脑扩散张量成像(DTI)扫描,应用FSL软件中的TBSS方法对患者组和对照组的DTI数据集进行分析,探索两组间各向异性分数(FA)、平均扩散系数(MD)、径向扩散系数(RD)和轴向扩散系数(AD)具有统计学差异的脑区。同时,将上述DTI参数与CSP患者的各项临床指标进行相关分析。结果 与对照组相比,CSP患者胼胝体、前放射冠、左侧上纵束的FA值存在不同程度降低,同时,患者组的胼胝体、丘脑后辐射、内囊、前后及上放射冠、双侧上纵束均表现出MD值和RD值升高,而AD值在两组间无统计学差异。此外,CSP患者胼胝体膝部的FA值与视觉模拟评分(VAS)呈线性负相关(r=-0.458,P<0.01),左侧上纵束的MD值与VAS呈正相关(r=0.495,P<0.01)。结论 CSP患者部分白质纤维束呈现出FA值降低合并MD值和RD值同时升高,特定脑区的FA值和MD值与疼痛强度密切相关,提示相应DTI参数可能成为评...     

儿童白质发育成熟的影响因素分析

目的 分析早产、缺血缺氧性脑病(HIE)病史以及癫痫对儿童白质发育成熟的影响.资料与方法 搜集本院67例进行过头颅MRI和扩散张量成像(diffusion tensor imaging,DTI)扫描的住院患儿.其中男39例,女28例,年龄6～117个月,平均51个月.人组患儿中,8例有HIE病史,8例早产,36例癫痫.DTI数据采用基于白质骨架的空间统计分析(tract-based spatial statistics,TBSS),提取11个感兴趣区域内各向异性系数(fractional anisotropy,FA),包括中脑的大脑脚、内囊前后肢、内囊的壳核后部分、丘脑后放射、放射冠、上纵束、下额枕束缚/下纵束、胼胝体膝部、体部、压部.癫痫的严重程度根据其对发育的影响进行评分.对不同白质束的FA值进行ANOVA检验.年龄、早产、HIE病史和癫痫评分这些因素对各纤维束FA值的影响采用线性回归分析进行统计学分析.结果 方差分析显示不同的纤维束间FA值差异存在统计学意义(F=162.676,P=0.000).除了内囊的壳核后部分和胼胝体压部,多数纤维束的FA值随着年龄增大而增加.放射冠的FA值表现出随年龄增加的统计学趋势(P=0.065).HIE病史与大脑脚,内囊的壳核后部分,丘脑后放射和上纵束的FA值呈现负相关关系(r=-0.212,P=0.036;r=-0.29,P=0.017;r=-0.326,P=0.005;r=-0.269,P=0.021).早产和癫痫评分这两个因素与纤维束的FA值无统计学意义的相关性.结论 TBSS可以用于儿童DTI数据的分析.HIE病史是可以引起儿童白质发育成熟障碍的一个确切因素.     

DTI在急性缺血性脑卒中所致皮质脊髓束损伤中的应用研究

目的:利用DTI探讨急性缺血性脑卒中病人大脑白质纤维束各向异性特征和皮质脊髓束受损与肌力的关系。方法:对9例正常被试和9例急性期缺血性脑卒中病人进行常规MR T1WI、T2WI和DTI检查,对数据进行离线后处理,采用dTV.II软件处理,获得FA图及方向编码彩色(DEC)图,并重建双侧皮质脊髓束3D纤维束图。结果:在正常组双侧白质纤维束FA值无明显差异,重建FA值图与方向编码彩色图可显示大部分主要的白质纤维束。在脑卒中病人组梗死区FA值显著低于健侧,两侧相比差异有显著性意义(t=4.570,P<0.001)。病变侧皮质脊髓束受压、变形、移位、部分断裂,皮质脊髓束受累情况与肌力有相关性(rs=0.888,P<0.05)。结论:DTI可显示脑内白质纤维束的走行及分布,为大脑白质纤维束的研究开辟了新的广阔领域。DTI FA值图及DEC图可以显示卒中病人梗死区白质纤维的方向与各向异性程度。3D纤维束图可以更立体直观的显示锥体束状况,有利于探讨皮质脊髓束损伤程度与肌力的关系,对临床及判断预后有重要价值。     

磁共振扩散张量成像在评估帕金森病脑内白质改变中的应用

目的 利用磁共振扩散张量成像技术(diffusion tensor imaging,DTI)评价帕金森病患者脑白质纤维束与正常老年组间的差异.方法 对23例临床诊断为原发性帕金森病(Parkinson's disease, PD)患者和相匹配的22例正常老年人行DTI成像,采用人工勾画感兴趣区(region of interest,ROI)的方法在DTI参数图,包括部分各向异性图(fractional anisotropy,FA)和平均扩散系数图(mean diffusivity,MD)上测量脑内主要白质纤维束的FA值及MD值,采用t检验的方法进行组间比较.结果 PD组双侧钩束、后扣带束及上纵束的FA值低于对照组(P＜0.05),双侧后扣带束及右侧上纵束的MD值高于正常组(P＜0.05).结论 PD的病理改变不仅存在于黑质纹状体系统,也累及白质纤维.     

Knee injury and Osteoarthritis Outcome Score (KOOS) - validation of a Swedish version

The Knee injury and Osteoarthritis Outcome Score (KOOS) is a self-administered instrument measuring outcome after knee injury at impairment, disability, and handicap level in five subscales. Reliability, validity, and responsiveness of a Swedish version was assessed in 142 patients who underwent arthroscopy because of injury to the menisci, anterior cruciate ligament, or cartilage of the knee. The clinimetric properties were found to be good and comparable to the American version of the KOOS. Comparison to the Short Form-36 and the Lysholm knee scoring scale revealed expected correlations and construct validity. Item by item, symptoms and functional limitations were compared between diagnostic groups. High responsiveness was found three months after arthroscopic partial meniscectomy for all subscales but Activities of Daily Living.     

Endovascular management of carotid-cavernous fistulas

Objective To investigate endovascular treatment of traumatic direct carotid-cavernous fistulas （CCF） and their complications such as pseudoaneurysms. Methods： Over a five-year period, 22 patients with traumatic direct CCFs were treated endovascularly in our institution. Thirteen patients were treated once with the result of CCF occluded, 8 twice and 1 three times. Treatment modalities included balloon occlusion of the CCF, sacrifice of the ipsilateral internal carotid artery with detachable balloon, coll embolization of the cavernous sinus and secondary pseudoaneurysms, and covered-stem management of the pseudoaneurysms. Results All the direct CCFs were successfully managed endovascularly. Four patients developed a pseudoaneurysm after the occlusion of the CCF with an incidence of pseudoaneurysm formation of 18.2% （4/22）. A total number of 8 patients experienced permanent occlusion of the ICA with a rate of ICA occlusion reaching 36.4% （8/22）. Followed up through telephone consultation from 6 months to 5 years, all did well with no recurrence of CCF symptoms and signs. Conclusion Traumatic direct CCFs can be successfully managed with endovascular means. The pseudoaneurysms secondary to the occlusion of the CCFs can be occluded with stent-assisted coiling and implantation of covered stents.     

The acutely limping child

Acute limping may be the result of multiple pathologies in children. The differential diagnosis varies based on the age of the child. Irrespective of age, the initial imaging work-up includes AP and frog leg radiographs of the pelvis and ultrasound; MRI may sometimes be helpful. In children less than 3 years, infections and trauma are most frequent. MRI is the imaging modality of choice when osteomyelitis is clinically suspected. Between the ages of 3 and 10 years, transient synovitis of the hip and Legg-Calvé-Perthes disease are main considerations but infection, inflammation and focal bony lesions are also considered. In children over 10 years, slipped capital femoral epiphysis also is considered.     

Do Balance Board Training Programs Reduce the Risk of Ankle Sprains in Athletes?

Introduction Ankle sprains are the most common musculo-skeletal injury that occurs in athletes,particularly in sports that require jumping and landing on one foot such as soccer,and basketball(1-4).These injuries often result in significant time loss from participation,long-term disability,and have a major impact on health care costs and resources(5-8).     

High Intensity Interval Training:New Insights

KEY POINTS ·High-intensity interval training(HIT)is characterized by repeated sessions of relatively brief，intermittent exercise.often performed with an“a11 out”effort or at an intensity close to that which elicits peak oxygen uptake(i.e.，≥90%of VO2 peak).     

Developmental validation of the PowerPlex(®) ESI 16 and PowerPlex(®) ESI 17 Systems: STR multiplexes for the new European standard

In response to the ENFSI and EDNAP groups’ call for new STR multiplexes for Europe, Promega^® developed a suite of four new DNA profiling kits. This paper describes the developmental validation study performed on the PowerPlex^® ESI 16 (European Standard Investigator 16) and the PowerPlex^® ESI 17 Systems. The PowerPlex^® ESI 16 System combines the 11 loci compatible with the UK National DNA Database^®, contained within the AmpFlSTR^® SGM Plus^® PCR Amplification Kit, with five additional loci: D2S441, D10S1248, D22S1045, D1S1656 and D12S391. The multiplex was designed to reduce the amplicon size of the loci found in the AmpFlSTR^® SGM Plus^® kit. This design facilitates increased robustness and amplification success for the loci used in the national DNA databases created in many countries, when analyzing degraded DNA samples. The PowerPlex^® ESI 17 System amplifies the same loci as the PowerPlex^® ESI 16 System, but with the addition of a primer pair for the SE33 locus. Tests were designed to address the developmental validation guidelines issued by the Scientific Working Group on DNA Analysis Methods (SWGDAM), and those of the DNA Advisory Board (DAB). Samples processed include DNA mixtures, PCR reactions spiked with inhibitors, a sensitivity series, and 306 United Kingdom donor samples to determine concordance with data generated with the AmpFlSTR^® SGM Plus^® kit. Allele frequencies from 242 white Caucasian samples collected in the United Kingdom are also presented. The PowerPlex^® ESI 16 and ESI 17 Systems are robust and sensitive tools, suitable for the analysis of forensic DNA samples. Full profiles were routinely observed with 62.5 pg of a fully heterozygous single source DNA template. This high level of sensitivity was found to impact on mixture analyses, where 54–86% of unique minor contributor alleles were routinely observed in a 1:19 mixture ratio. Improved sensitivity combined with the robustness afforded by smaller amplicons has substantially improved the quantity of data obtained from degraded samples, and the improved chemistry confers exceptional tolerance to high levels of laboratory prepared inhibitors.