MRS和DTI对放疗前后脑胶质瘤瘤周水肿的观察与分析

目的:应用MRS和DTI观察脑胶质瘤放疗前、后肿瘤周围水肿区变化。方法:31例病理诊断明确的脑胶质瘤术后患者,分别在放疗前、后行MRI平扫+增强+MRS+DTI检查。分析肿瘤瘤周水肿区代谢物比值的变化[胆碱(Cho)/肌酐(Cr)、Cho/N-乙酰天门冬氨酸(NAA)、NAA/Cr]及部分各向异性(fractional anisotropy,FA)值、ADC值变化。结果:放疗后瘤周水肿区Cho/Cr、Cho/NAA、NAA/Cr值较放疗前下降,其中Cho/Cr差异有统计学意义(P<0.05),Cho/NAA、NAA/Cr值差异无统计学意义(P>0.05);瘤周水肿区域放疗后FA值升高(P>0.05),ADC值下降(P<0.05)。结论:MRS及DTI能显示肿瘤水肿区放疗后的早期变化,较早反映放疗效果。     

鼻咽癌放射性脑损伤的MR扩散张量成像研究

目的 应用MR扩散张量成像(DTI)监测鼻咽癌放射性脑损伤急性期和亚急性期的颞叶微观结构变化.资料与方法 对2006年7月至2009年5月间80例确诊为鼻咽癌并首次接受放射治疗(简称放疗)的患者,在放疗前和接受剂量为20 Gy、40 Gy、60 Gy以及其中放疗结束后的47例第1、2、3个月分别进行常规颅脑MRI和DTI,动态观察不同时间段DTI的表观扩散系数(ADC)和部分各向异性(FA)值的变化趋势,并进行分析.结果 自放疗开始至结束后3个月常规颅脑MRI未见异常信号.放疗过程中和放疗结束后3个月ADC值升高、FA值减低,FA值放疗后3个月的降低幅度大于放疗期间的降幅,ADC值和FA值在放疗期间不同剂量阶段差异无统计学意义(P＞0.05),放疗后3个月差异具有统计学意义(P＜0.05).结论 虽然鼻咽癌放射性脑损伤的急性期和亚急性期常规MRI未见异常,但仍存在微观结构上的变化,导致细胞内外水分子扩散减慢.DTI从分子水平评价放射性脑损伤的优势在亚急性期更明显,为预防不可逆性脑损伤提供客观依据.     

鼻咽癌放射治疗后放射性脑损伤急性反应早期的1H-MR波谱研究

目的评价1H-MR波谱（1H-MRS）对鼻咽癌放射治疗（简称放疗）后放射性脑损伤急性反应早期的诊断价值.方法对18例已被病理证实且为首次行放疗的鼻咽癌患者进行前瞻性研究,于不同时间段对其双侧颞叶（共72个部位,颞叶前后部各为36处）进行常规MR和1H-MRS成像,成像时间为放疗前和放疗后接受放射剂量20Gy、40 Gy及60Gy时,成像序列为轴面SE T1WI、T2WI、T2液体衰减反转恢复序列（T2FLAIR）、三维扰相稳态梯度恢复采集T1序列（3D-SPGR T1＊）.以序列T2FLAIR或3D-SPGR T1＊为波谱成像的定位图,采用点分辨法进行多体素及单体素波谱成像,观察不同时间段颞叶各部位谱线的形态学改变及各代谢物间比值的变化.结果放疗后,双侧颞叶在常规MRI均未见明显信号改变,而在1H-MRS成像上,双侧颞叶前部谱线形态均有不同程度的改变,而颞叶后部无明显改变,表现为局部N-乙酰天门冬氨酸（NAA）峰和胆碱（Cho）峰降低,Cho/肌酸（Cr）、NAA/Cr及NAA/Cho比值在不同时间段均有下降;在接受放射剂量20Gy时,颞叶前叶有20处,占所有颞前叶的比例为56%（20/36）;40 Gy时有22处,占61%（22/36）;60Gy时有13处,占36%（13/36）.而谱线为NAA与Cho峰倒置在20Gy时,颞叶前叶有4处,占11%（4/36）;40 Gy时,有10处,占28%（10/36）;60 Gy时为23处,占64%（23/36）.与接受射线剂量呈明显正相关,不同剂量其同一比值差异有统计学意义（P＜0.05）.结论1H-MRS可在组织细胞代谢水平发现鼻咽癌放疗后急性反应早期的放射性脑损伤.     

鼻咽癌放疗后迟发性放射性脑损伤的MRI特征

目的 探讨鼻咽癌放疗后迟发性放射性脑损伤的MRI特征.资料与方法 回顾性分析57例鼻咽癌放射治疗后10个月～20年发生的迟发性放射性脑损伤患者的MRI、表观扩散系数(ADC)、磁共振波谱学(MRS)表现.结果 病变主要位于颞叶,颞叶病灶范围较大时累及额叶或小脑,少部分病灶位于脑干,其MRI示坏死脑组织的T_1、T_2弛豫时间延长,呈不均匀信号改变,并脑水肿.增强扫描坏死区呈散在斑点状、小结节状强化,或皱缩状、"花边"状强化团块;ADC为稍高信号;MRS表现为胆碱(Cho)峰升高、N-乙酰天门冬氨酸(NAA)峰降低.其中,54例发生于颞叶,2例合并额叶损伤,1例合并小脑损伤,3例发生于脑干;颞叶病变累及双侧38例,单侧16例.结论 MRI可以清晰显示鼻咽癌放疗后放射性脑损伤的范围,ADC及MRS具有一定特征性,有益于鉴别诊断.鼻咽部随访复查应仔细观察双侧颞叶及脑干情况.     

儿童型肾上腺脑白质营养不良的2D-1H MRSI和DTI初步应用

目的探讨2D-MRSI和DTI在儿童型肾上腺脑白质营养不良的综合应用价值.方法对3例儿童型肾上腺脑白质营养不良患儿行2D-MRSI、DTI和常规MRI检查,比较病变区域代谢物NAA/Cho、NAA/Cr和Cho/Cr比值与ADC和FA的关系,以及它们与T2WI信号强度的相关性;测量常规MRI阴性的ALD额顶叶白质的ADC和FA值有无异常.结果病变T2WI信号强度与NAA/Cho比值和FA负相关,与ADC正相关,即T2WI信号越高,NAA/Cho越低、ADC越高及FA越低,且具有从外到内的层次性.各种代谢物比值以NAA/Cho 比值与ADC和FA相关最密切.DTI不能发现常规MRI阴性的ALD白质病变.结论 MRSI和DTI与常规MRI表现具有一定的相关性,2D-MRSI和DTI可为儿童型肾上腺脑白质营养不良诊断提供更多的信息.     

鼻咽癌放疗后靶区MRI表现正常的脑组织1H-MRS表现

目的:采用二维相位编码磁共振波谱(2D 1H-MRS)成像分析鼻咽癌放疗后常规MRI表现正常者双侧颞叶放疗靶区脑组织代谢改变,探讨2D 1H-MRS在早期放射性脑损伤中的应用价值.方法:对31例(病例组)鼻咽癌放疗后常规MRI表现正常者共40个颞叶和23例(33个颞叶)健康成年人(对照组)均行2D 1H-MRS检查,在双侧颞叶脑白质区域测量N-乙酰天门冬氨酸(NAA)、肌酸(PCr)和胆碱(Cho)值及相互间比值.结果:病例组颞叶区NAA、PCr降低,Cho升高,与对照组间差异无显著性意义(P＞0.05);病例组Cho/PCr升高、NAA/Cho降低,与对照组间差异有显著性意义(P《0.05).结论:2D 1H-MRS能发现鼻咽癌放疗后常规MRI所不能显示的脑组织改变,为放射性脑损伤的早期诊断提供了一种新的影像学诊断手段.     

DTI 和 MRS 在 AIDS 相关脑内结核中的临床应用研究

目的：探讨扩散张量成像(DTI)和磁共振波谱成像(MRS)定量指标对获得性免疫缺陷综合征(AIDS)相关机会性感染脑内结核的诊断价值。方法收集17例 AIDS 合并颅内结核患者及16例正常志愿者,行常规 MRI、DTI 及多体素 MRS 扫描,观察病灶形态学表现,测量病例组病灶实质区、水肿区、正常区及对照组相应正常区 ADC、FA、rADC、rFA、NAA/Cho、NAA/Cr 及 Cho/Cr 定量指标,并分析其差异性。结果AIDS 相关脑内结核实质区、水肿区及正常区各指标经方差分析均有统计学意义,两两比较,除水肿区与正常区 NAA/Cr 外,其余均有统计学差异(P<0.05),实质区 ADC 值、FA 值、rADC 值、rFA 值,NAA/Cho、NAA/Cr 均低于水肿区,Cho/Cr 高于水肿区和正常区。受试者工作特征曲线(ROC)分析 rFA 值用于区分实质区及水肿区的效能最高(P <0.05)。2组间正常区比较除 Cho/Cr 外,各指标均有统计学意义(P <0.05)。结论DTI 可以反映 AIDS 脑内结核所引起的脑结构微细改变, MRS 能反映脑内结核的早期病理代谢特点。     

斜坡滑动撞击建立兔轻型脑损伤模型及功能MRI实验研究

目的建立一个控制性与重复性好的脑损伤动物模型,并应用MRI分子影像方法检查轻型脑损伤的病理生理微观改变。材料与方法自制斜坡滑动装置,建立兔轻型脑损伤模型。对实验兔在撞击前、撞击后即刻和安静休息1h后分别进行CT平扫和MRI T1WI、T2WI、FLAIR、SWI、MRS、DTI(FA值)、DWI(ADC值)检查。根据兔脑受撞击后意识表现、CT检查和MRI T1WI、T2WI、FLAIR、SWI检查阴性,诊断兔轻型脑损伤。对比实验兔撞击前后的MRS、DTI、DWI检查结果,分析兔轻型脑损伤的异常功能表现。结果兔脑受轻微撞击后,NAA、Cho、Cr及Cr2峰值均立即显著降低,1h后检查又基本恢复到撞击前水平。脑干DTI的FA值在撞击后也立即显著降低,1h后检查基本恢复到撞击前水平。而脑干DWI的ADC值和端脑的FA值及ADC值在撞击前后并没有显著改变。结论本实验方法可以建立符合要求的兔轻型脑损伤模型,功能MRI检测表明轻型脑损伤主要是脑细胞代谢障碍引起的生理改变,这种功能性改变可以恢复。     

鼻咽癌放射性脑损伤迟发反应期的磁共振波谱研究

目的 探讨磁共振波谱(magnetic resonance spectroscopy,MRS)成像在鼻咽癌放射治疗后迟发反应期的应用价值.资料与方法 对同期80例确诊为鼻咽癌并首次接受放射治疗(简称放疗)的患者进行放疗前、放疗结束时和放疗结束后的47例患者第3,6,12个月分别行常规MRI和MRS成像.MRS成像以T2液体衰减反转恢复(FLAIR)序列作为定位图,点分辨法进行多体素采集,观察放疗后不同时期主要代谢物的变化趋势,并进行分析.结果 47例各阶段MRI常规扫描未见明显异常.放疗结束时,N-乙酞天门冬氨酸(NAA)/肌酸(Cr)、胆碱(Cho)/C:和NAA/Cho比值降低,放疗结束后3个月,三者比值进一步减小达到最低点,但幅度小于放疗过程中,与放疗前比较差异具有统计学意义(P<0.05);放疗结束后3-12个月三者比值呈上升趋势,至第12个月时三者比值均高于放疗结束时,Cho/Cr和NAA/Cho分别接近和略低于放疗前.结论 MRS成像通过监测代谢物的浓度变化,能无创性反映鼻咽癌放射性脑损伤迟发反应期的修复过程.     

鼻咽癌放射治疗后放射性脑损伤的扩散张量成像与1H-MR波谱研究

目的 探讨双侧颞叶脑组织在鼻咽癌放射治疗后不同时期的DTI与1H-MRS变化特点.方法 选择48例鼻咽癌放射治疗后常规MRI表现正常的患者(患者组)及24名健康志愿者(正常组)行DTI及1H-MRS检查,将扫描图像进行后处理和波谱分析,测量双侧颞叶DTI的各向异性分数(FA)值、ADC值及3个本征值λ1、λ2、λ3,以及1H-MRS中双侧颞叶前部白质N-乙酰天冬氨酸(NAA)/胆碱(Cho)、NAA/肌酸(Cr)及Cho/Cr比值,并将鼻咽癌放射治疗后患者按放射治疗后不同时期分为放射治疗后0～6、6～12、>12个月,分别定义为患者组1(16例)、2(6例)、3(26例),计算放射治疗后双侧颞叶脑组织各测量指标数值.所得数据采用单因素方差分析.结果 鼻咽癌放射治疗后6个月内、6～12个月、12个月后以及正常组DTI的FA值分别为0.445±0.017、0.460±0.016、0.461±0.025、0.473±0.023,ADC值分别为(8.51±0.43)×10-4、(8.48±0.34)×10-4、(8.40±0.33)×10-4、(8.68±0.57)×10-4mm2/s,3个本征值中最大本征值λ1分别为(1.251±0.065)×10-3、(1.293±0.051)×10-3、(1.317±0.074)×10-3、(1.350±0.091)×10-3 mm2/s,以上3个指标组间差异均有统计学意义(F值分别为10.873、3.399、9.750,P值均<0.05).λ2、λ3值组间比较差异无统计学意义.1H-MRS的NAA/Cho分别为0.910±0.112、0.972±0.101、1.060±0.095、1.261±0.105,NAA/Cr分别为1.212±0.236、1.208±0.183、1.228±0.236、1.435±0.225,组间差异均有统计学意义(F值分别为52.840、8.176,P值均<0.01).Cho/Cr组间比较差异无统计学意义.结论 DTI结合1H-MRS在鼻咽癌放射治疗后监测评价脑组织的放射损伤程度方面具有一定的指导作用,可为放射性脑损伤的动态早期监测提供科学依据.     

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.