猫急性脑静脉闭塞模型的建立

目的 建立一个稳定的急性脑静脉闭塞动物模型。材料与方法 家猫22只,随机分为2组(手术组18只,假手术组4只)。采用开颅上矢状窦穿刺注射液体栓塞剂——醋酸纤维素聚合物(CAP)联合双侧颈外静脉结扎制备急性脑静脉闭塞动物模型,在术后1、3、6、12、24、48h用扩散加权成像(DWI)、T2WI技术对模型行MRI扫描,并和大体标本、光镜及电镜对照研究。结果 手术组14只造模成功。由于手术误操作,1、6、12、24h组各1只实验失败。1、3、48h组各1只脑实质MRI表现阴性。24h组1只脑皮层异常信号面积太小,未做MRI定量分析。10只猫脑病变位于上矢状窦旁皮层及皮层下。仅DWI能显示早期脑实质病变,3h后,DWI、T2WI均能显示病变。大体病理学14只上矢状窦及窦旁额、顶叶桥静脉及皮层静脉内见CAP凝固呈铸型改变,12h后窦旁皮层病变区被伊文思蓝不同程度蓝染。显微病理学见术后1～3h以细胞内毒性水肿为主,3～24h血管源性水肿逐渐出现并占优势．24～48h出现静脉性脑梗死、脑出血。假手术组4只均未见上述各种异常表现。结论 上矢状窦穿刺注射CAP联合双侧颈外静脉结扎制备急性脑静脉闭塞动物模型的方法是可行的。     

急性脑静脉闭塞DWI、CT灌注成像与病理学相关性的对比实验研究

目的:观察脑静脉闭塞模型脑实质损害区MR扩散加权成像(DWI)、CT灌注成像(CTP)及病理学的变化规律,探讨模型在该病研究中的价值。方法:新西兰大白兔28只,随机分为2组(手术组24只,对照组4只)。术后1、3、61、2、24和48h行DWI和CTP检查,观察扩散异常容积、ADC值和血流动力学变化规律,其结果与病理学对照研究。结果:DWI能早期显示脑实质病变,术后3hDWI和T2WI均能显示病变。术后6h前DWI上扩散异常容积明显大于T2WI上异常高信号区的容积(t=13.69,P<0.01);术后12h、24h及48h T2WI病变容积与DWI上的扩散异常容积无显著差异(t值分别为1.467、0.996及2.017,P值均>0.05)。ADC值早期下降随后逐渐回升。CTP示术后6~12h病变中心区CBV和CBF降低,而病变边缘区CBV增加或正常或轻度降低;术后12~24h病变中心区和边缘区CBV和CBF均明显降低。病理学示以血管源性水肿为主,12h后出现脑组织大量坏死。对照组未见上述各种异常表现。结论:DWI和CTP可准确评价急性脑静脉闭塞模型脑实质损害程度和血流动力学改变,指导临床治疗。     

急性脑静脉闭塞脑损伤治疗时间窗初探:DWI与病理学对照实验研究

目的:探讨急性脑静脉闭塞模型脑实质损伤治疗时间窗的存在及其意义.方法:选择新西兰大白兔28只随机分为2组(实验组24只,对照组4只),实验组动物经一侧颈内静脉注入醋酸纤维素聚合物(CAP),分别于术后1、3、6、12、24和48 h行T1WI、T2WI和扩散加权成像(DWI)检查.各时间点MR扫描后取兔脑组织做胶质纤维酸性蛋白(GFAP)表达的免疫组化研究及电镜观察.结果:DWI、T2WI、GFAP的表达和电镜检查均能显示急性脑静脉闭塞模型脑实质损伤及其变化.DWI在术后1 h即能显示脑实质病变(ADC值下降),术后3 h DWI和T2WI均能显示病变;术后6 h前,DWI上有扩散异常的脑组织容积明显大于T2WI上异常高信号区的容积(t=13.69,P＜0.01);术后12、24和48 h病变区ADC值逐渐回升,T2WI上病变容积与DWI上的扩散异常区的容积比较,差异无显著性意义(t值分别为1.467、0.996和2.017,P＞0.05).术后1 h病变区GFAP阳性细胞增多,染色加深,胞体增大,突起增粗增长,术后3～6 h变化更明显,病理学改变以血管源性水肿为主,12 h后出现脑组织大量坏死.对照组未见上述各种异常表现.结论:DWI可准确评价急性脑静脉闭塞模型脑实质损伤程度,结合GFAP的表达,在探讨急性脑静脉闭塞脑损伤的治疗时间窗的存在及其意义中具有重要价值,在其发生发展过程中确实存在潜在的治疗时间窗.     

急性脑静脉闭塞模型的CT灌注成像与病理学评价

目的用CT灌注成像（CTPI）和病理学方法对急性脑静脉闭塞动物模型进行评价. 材料与方法家猫22只,随机分为2组（手术组18只,假手术组4只）.手术组采用开颅上矢状窦穿刺注射液体栓塞剂--醋酸纤维素聚合物（CAP）制备急性脑静脉闭塞动物模型,术后1、3、6、12、24、48 h用CTPI对各组模型的脑血流动力学改变进行观察,其结果和病理学对照研究.假手术组只做钻孔颅骨开窗暴露上矢状窦,但不进一步操作. 结果手术组12只猫CTPI出现脑血流异常灌注区.术后1 h,病变表现为局部脑血容量（rCBV）轻度增加,局部脑血流量（rCBF）轻度降低,平均通过时间（MTT）稍延长;3～6 h后病变中心区主要表现为 rCBV和rCBF降低,而病变边缘区rCBV增加或正常或轻度降低,rCBF降低;12～24 h后病变中心区和边缘区rCBV和rCBF均明显降低.大体病理学检查上矢状窦、桥静脉及皮层静脉内见CAP凝固呈铸型改变,3 h后病变区见伊文思蓝不同程度蓝染.显微病理学检查10只猫出现脑实质损害,病变以血管源性水肿为主,12 h后出现出血性脑梗死.假手术组4只猫均未见上述各种异常表现. 结论功能CT灌注成像是评价急性脑静脉闭塞模型血流动力学改变的一种准确、敏感的方法,可早期评价脑实质损害的程度.     

急性脑静脉闭塞CT灌注成像的实验研究

目的观察脑静脉闭塞模型脑实质损害区CT灌注成像（CTP）变化规律,探讨该模型在该病研究中的价值。方法新西兰大白兔28只,随机分为2组（实验组24只,对照组4只）。一侧颈内静脉注入醋酸纤维素聚合物（CAP）合并双侧颈外静脉结扎术后1、3、6、12、24和48h行CTP检查对各组模型的脑血流动力学改变进行观察。结果实验组21只造模成功,其中3h及12h组各有1只在CTP上无明显异常表现,有19只CTP检查示脑血流灌注异常。术后1～3h,病变区脑血容量（CBV）轻度增加或正常,脑血流量（CBF）轻度降低,平均通过时间（MTT）稍延长;6～12h后病变中心区主要表现为CBV和CBF降低,MTT延长,而病变边缘区CBV增加或正常或轻度降低,CBF降低,MTT缩短;12～24h后病变中心区和边缘区CBV和CBF均明显降低,MTT明显延长。各时段病变中心区和边缘区的CBV%、CBF%、MTT%的差异均有统计学意义（P值均〈0.05）。对照组未见上述各种异常表现。结论 CT灌注成像可准确、敏感地反映急性脑静脉闭塞模型的血流动力学改变。     

急性脑静脉闭塞磁共振扩散张量成像的实验研究

目的 对急性脑静脉闭塞模型进行磁共振扩散张量成像(DTI),观察脑实质损害的扩散规律及脑白质纤维束的完整性.材料与方法取家猫30只随机分为手术组(n=24)和假手术组(n=6).手术组制备急性脑静脉闭塞动物模型,假手术组仅行开颅上矢状窦暴露.术后采用常规MRI和DTI对各组模型脑实质损害病灶进行连续动态观察,测最病变区的平均扩散系数(ADCav)和各向异性分数(FA)值,计算病变区与健侧区的ADCav、FA比值.用纤维示踪技术(FT)显示脑白质纤维柬的完整性,并与病理学对照.结果 手术组24只猫,9只常规MRI检查为阴性;15只猫脑实质出现异常信号,术后1 h ADCav值较健侧降低,3 h后ADCav值较健侧逐渐增高,12 h后增高明显.FA值于术后各时问点均降低.各时间点病变区与健侧ADCav、FA值差异有统计学意义(P<0.05).各时间点ADCav、FA比值差异有统计学意义(F值分别为62.07、9.37.P<0.05).术后1 h,FT显示脑白质纤维束移位和穿过病灶区,6 h后脑白质纤维束断裂、破坏,12 h后脑白质纤维束于病灶边缘处中断.术后1 h病灶区出现细胞毒性脑水肿,3 h后以血管源性水肿为主,12 h后出现静脉性脑梗死、脑出血.假手术组未见上述异常表现.结论 DTI能清楚显示并定量判断急性脑静脉闭塞脑实质损害的动态变化规律,FT能更好地显示脑白质纤维柬的受损和移位.     

DWI及FLAIR技术在急性脑梗塞中的临床应用探讨

目的　探讨弥散加权成像 (DWI)技术及FLAIR技术在急性脑梗塞中的临床应用价值。方法　收集 60例急性脑梗塞患者 ,其中超急性期 ( <6h) 7例 ,急性期 ( 6～ 2 4h) 2 4例 ,亚急性期 ( 2 4～ 72h) 2 9例。均行常规T1WI ,T2 WI及FLAIR ,DWI扫描 ,比较病灶显示范围、边界及对比度 ,并计算病灶的ADC与rADC值。结果　①DWI及FLAIR序列对病灶的显示范围、对比均优于常规T1WI、T2 WI ,而且DWI对病灶显示较FLAIR更清晰。②DWI的b值越高 ,弥散效果越好 ,显示病灶越清晰。同时 ,弥散全方向比单方向显示病灶更清晰。③所有病例病灶的ADC与rADC值均下降。结论　DWI技术对急性脑梗塞病变敏感性最高 ,结合FLAIR技术可准确、可靠地诊断急性脑梗塞     

MR扫描序列优化组合诊断脑出血的实验研究

目的:初步探讨MR敏感扫描序列在诊断超急性期和急性期脑血肿中的应用价值.方法:32只健康家兔随机分为2组(实验组24只,对照组8只).实验组动物利用兔自身血注入形成脑血肿,分时间点(术后3、6、12、24和48 h)进行MR扫描,扫描序列包括T1WI、T2WI、T2*WI和扩散加权成像(DWI),并与各时段组织学表现进行对照分析.结果:血肿形成后每个时段T2*WI均可清晰显示脑内血肿,表现为低信号,边界清.利用容积测量软件测量实验组T2*WI上脑血肿体积,平均值为(310±19)μl,平均注血量为(250±20)μl,两者差异无显著性意义(t=0.003,P＜0.05).各时间点脑血肿在DWI上表现为中心低信号,周围有高信号环.脑血肿在T1WI、T2WI上信号无特征性,边界欠清.组织学检查显示6 h以后可见血肿周围有中性粒细胞和少量小胶质细胞浸润,12 h后可见血肿中心少量红细胞开始溶解.对照组各实验对象在组织学和MRI图像上均未见脑血肿形成.结论:T2*WI、DWI序列对诊断超急性期和急性期脑内出血的敏感性较高,结合常规扫描序列(T1WI和T2WI)对诊断超急性期及急性期脑血肿具有一定临床应用价值.     

MRI对脑静脉畸形的诊断价值

目的:探讨MRI对脑静脉畸形(CVM)的诊断价值。方法:收集本院18例脑静脉畸形病例,均行磁共振T1WI、T2WI、FLAIR、SWI、DWI、MRA及T1WI增强扫描的资料。结果:CVM位于幕下5例,幕上13例,18例均呈典型的"海蛇头"征。MRI显示髓静脉呈长T1长T2信号,引流静脉呈短T1稍长T2信号或长T1长T2信号。FLAIR上髓静脉为稍高信号,引流静脉为低信号或稍高信号。SWI及DWI上髓静脉和引流静脉均为低信号。增强呈"海蛇头"样改变,即多条髓静脉呈辐射状汇入粗大的引流静脉。结论:MRI能明确诊断脑静脉畸形,T1WI增强扫描及SWI均较敏感。SWI对CVM的诊断价值明显优于常规MRI序列。     

T2 FLAIR增强扫描在颅内病变中价值的初步研究

目的探讨增强T2FLAIR在颅内病变诊断中的价值。方法58例资料完整并在增强T1WI或增强FLAIR上有强化的患者,确定增强T1WI和增强FLAIR上病变有无强化、强化的显著性、肿瘤性病变强化区的边界。结果3例脑梗塞在增强T1WI上未见强化,3例脑肿瘤在增强FLAIR上未见强化,1例脑膜瘤在增强FLAIR上呈负性强化;余51例中11例在增强FLAIR上强化更显著,16例在2个序列上强化相似,24例在T1WI上强化更显著。4例结核的脑膜病变范围和1例静脉窦血栓者回流受阻的皮层静脉在增强FLAIR上显示更加明确。结论增强T2FLAIR在颅内病变的诊断中有一定的价值,当增强T1WI显示不满意、怀疑脑膜或皮层血管病变时,应行增强T2FLAIR。     

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.