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1.
目的 观察三维动脉自旋标记(ASL)成像联合弥散加权成像(DWI)评估急性脑梗死(ACI)缺血性半暗带(IP)及预后的价值。方法 回顾性分析45例ACI患者的颅脑ASL图像及DWI,根据随访3个月末改良Rankin量表(mRS)评分结果,将患者分为预后好、中等和差组。测量病灶最大层面DWI高信号面积(SDWI)和ASL异常灌注面积(SASL),评估患者是否存在IP;记录梗死病灶(IL)、近病灶边缘脑组织(BNL)及相应对侧区域脑血流量(CBF)和表观弥散系数(ADC)值,计算患侧/对侧相对值(rCBF和rADC)。比较不同预后组内IL与对侧CBF、ADC值差异及各组间rCBF及rADC差异,分析IL及BNL的rCBF对于ACI预后差的单独诊断效能和联合诊断效能,观察rCBF、rADC与mRS评分的相关性。结果 45例ACI中,40例IL区表现为低灌注,将其纳入研究;其中23例存在IP,与不存在IP患者预后差异有统计学意义(χ2=6.742,P=0.034)。不同预后组内IL的CBF和ADC值、预后好组及中等组BNL的CBF值均低于对侧(P均<0.05)。预后差组IL的rCBF与预后好组及预后中等组差异均有统计学意义(P均<0.05),而不同预后组间BNL的rCBF差异无统计学意义(F=3.20,P=0.05)。IL和BNL的rCBF评估ACI预后差的AUC分别为0.92和0.79,最佳界值分别为0.41和0.93,约登指数分别为0.72和0.57;两者联合AUC为0.94,约登指数为0.79。IL的rCBF与mRS评分呈负相关(r=-0.642,P<0.001)。结论 三维ASL联合DWI可用于评估ACI患者IP及预后,为制定ACI治疗方案提供参考。  相似文献   

2.
  目的  探究三维动脉自旋标记灌注成像(3D-ASL)联合弥散加权成像(DWI)、血管成像(MRA)对急性缺血性脑梗死缺血半暗带区域(IP)的评估价值。  方法  选取2021年1月~2022年6月本院收治的急性缺血性脑梗死患者62例,所有患者均接受3D-ASL、DWI、MRA扫描,根据病灶最大层面DWI高信号面积、ASL异常灌注面积评估患者是否存在IP,根据患者发病至首次MRI检查时间(T)将患者分为超急性期(T<6 h)和急性期(6 h≤T≤24 h)。记录患者中心梗死区、IP区与IP对侧镜像区的表观扩散系数(ADC)、脑血流量(CBF)值,根据MRA图像对血管狭窄程度进行分级。  结果  急性缺血性脑梗死患者病灶DWI表现为斑点状或小片状高信号,48例患者3D-ASL异常灌注面积明显大于DWI异常高信号面积,显示存在IP区;MRA显示颅内某支主干动脉节段性狭窄,远端血管明显变细甚至消失,部分显示血管无明显异常。患者不同区域CBF、ADC值比较:中心梗死区  结论  3D-ASL联合DWI、MRA检测可准确评估急性缺血性脑梗死患者IP区的存在和血管狭窄程度,有利于梗死临床精准化治疗方案的选择。   相似文献   

3.
目的:分析磁共振动脉自旋标记灌注技术(MRI)在诊断缺血性脑血管病的价值。方法:抽选我院64例接受磁共振检查的脑血管病患者,均行磁共振常规扫描、磁共振血管成像和三维动脉自旋标记灌注成像检查。脑梗死患者分为两个亚组:即结合ASL灌注异常面积与DWI信号异常面积分成ASL>DWI组、ASL≈DWI组和ASL相似文献   

4.
目的 探讨DWI及ADC值鉴别诊断良恶性脑膜瘤以及对脑膜瘤病理分型的价值。方法 回顾性分析经手术病理证实的109例脑膜瘤患者,于Functool图像后处理工作站上测量肿瘤实质区、瘤周水肿区及对侧正常脑白质ADC值,计算相对ADC值(rADC);比较不同病理亚型及良恶性脑膜瘤的DWI信号特征及ADC值的差异。结果 良恶性脑膜瘤DWI信号差异无统计学意义(χ2=4.95,P=0.29),不同病理亚型脑膜瘤DWI信号差异亦无统计学意义(χ2=17.86,P=0.12)。良恶性脑膜瘤肿瘤实质强化区rADC值(rADCt)差异有统计学意义(t=2.57,P=0.01),而二者肿瘤实质强化区ADC值(ADCt)、瘤周水肿区ADC值(ADCe)及瘤周水肿区rADC值(rADCe)差异均无统计学意义(P均>0.05)。血管瘤型脑膜瘤ADCt及rADCt值高于其他各病理亚型(P均<0.05);间变型脑膜瘤ADCt及rADCt低于纤维型及脑膜皮细胞型(P均<0.05)。结论 rADCt可用于鉴别良恶性脑膜瘤;ADCt及rADCt值对鉴别诊断脑膜瘤病理亚型具有一定的临床价值。  相似文献   

5.
目的 探讨体素内不相干运动(IVIM)成像评价亚急性期脑梗死弥散和灌注情况的价值。方法 回顾性分析35例亚急性期脑梗死患者的MR影像资料,包括常规DWI、IVIM成像及三维动脉自旋标记(3D-ASL)序列检查。通过常规DWI序列获得ADC图,IVIM序列获得纯水分子扩散系数(D)图、灌注相关扩散系数(D*)图、灌注分数(f)图,3D-ASL序列获得脑血流量(CBF)图。分别测量脑梗死灶及对照侧镜像区ADC值、D值、D*值、f值、CBF值及其相对值(rADC、rD、rD*、rf、rCBF)。比较脑梗死灶与对照侧镜像区各参数的差异,并分析rADC值与rD、rD*、rf值的相关性及rCBF值与rD、rD*、rf值的相关性。结果 脑梗死灶ADC、D、D*、f、CBF值均较对照侧镜像区减低(P均<0.05)。rADC值与rD、rf值呈正相关(r=0.687、0.601,P=0.005、0.018);rCBF值与rf值呈正相关(r=0.581,P=0.022)。结论 IVIM成像能同时提供亚急性期脑梗死的灌注及弥散信息,有助于进一步阐明亚急性期脑梗塞的机制。  相似文献   

6.
目的 探讨高分辨率扩散加权成像(RESOLVE-DWI)在大鼠颅脑胶质瘤成像中的应用价值。方法 选取20只Wistar大鼠建立C6胶质瘤模型,并进行常规MRI、单次激发平面回波成像(SS-EPI) DWI及RESOLVE-DWI序列扫描。分别计算SS-EPI DWI和RESOLVE-DWI图像的SNR、CNR及ADC值,评价图像畸变程度,对图像质量进行主观评分,并进行统计学分析。结果 RESOLVE-DWI解剖结构显示规则,颅脑结构轮廓更加接近真实颅脑结构。RESOLVE-DWI图像的SNR及CNR均明显高于SS-EPI DWI(P均<0.05)。RESLOVE-DWI图像评分高于SS-EPI DWI(P<0.05)。RESLOVE-DWI与SS-EPI DWI图像肿瘤中心区和对侧正常脑组织ADC值差异均无统计学意义(P均>0.05)。RESLOVE-DWI和SS-EPI DWI图像中肿瘤中心区ADC值均明显高于对侧正常脑组织(P均>0.05)。结论 RESOLVE-DWI可提供满足临床诊断需求的DWI及ADC图像,较SS-EPI DWI图像质量明显提高。  相似文献   

7.
目的 探讨应用DWI监测骨肉瘤诱导和新辅助化疗反应的价值。方法 收集经病理证实的26例骨肉瘤患者,所有患者化疗前后均接受常规MR及DWI扫描。根据化疗反应情况分为反应差组(n=12,肿瘤坏死范围≤90%)和反应好组(n=14,肿瘤坏死范围>90%)。测量并比较治疗前后骨肿瘤的ADC值、肿瘤体积及其变化率。结果 化疗前及化疗后,反应好组与反应差组间肿瘤体积和ADC值差异均无统计学意义(P均>0.05)。两组化疗前后肿瘤体积变化率差异无统计学意义(P=0.05),而ADC值变化率的差异有统计学意义(P<0.001)。结论 应用DWI测定化疗前后骨肉瘤ADC值改变率有助于监测肿瘤对诱导化疗和新辅助化疗的反应。  相似文献   

8.
目的 探讨动脉自旋标记(ASL)灌注加权成像及DWI在评价新生儿缺氧缺血性脑病(HIE)中的应用价值。方法 对临床诊断为HIE的56例足月新生儿(HIE组)行常规MR(T1WI、T2WI、T2 FLAIR)及ASL、DWI,并以10例无HIE病史的轻度高胆红素血症足月新生儿为对照组。以临床诊断结果作为诊断金标准计算敏感度及特异度。选择双侧基底核区(尾状核头、豆状核)、丘脑、额叶白质(侧脑室上缘水平)为ROI,测量两组rCBF及ADC值,并分析两组各ROI的rCBF及ADC值的差异,并分析各ROI rCBF与ADC值的相关性。结果 常规MRI序列检测HIE的敏感度41.38%(12/29)、特异度55.56%(15/27);DWI序列的敏感度及特异度为50.00%(12/24)、46.88%(15/32);ASL检测HIE的敏感度及特异度为34.48%(10/29)、92.59%(25/27)。HIE组丘脑及豆状核rCBF较对照组明显升高(t=2.93、2.74,P=0.004、0.010),尾状核头部与额叶白质的rCBF较对照组差异无统计学意义。HIE组丘脑、额叶白质及豆状核ADC值较对照组减低(t=2.44、2.39、2.25,P=0.025、0.030、0.040)。丘脑和豆状核的rCBF与ADC值呈负相关(r=-0.355,P<0.01,r=-0.471,P=0.02)。结论 HIE时丘脑及豆状核血流量代偿性增加,局部脑组织水分子弥散受限。ASL及DWI技术联合应用有助于反映足月新生儿HIE的病理过程。  相似文献   

9.
目的 探讨伪连续动脉自旋标记ASL(PCASL)在脑梗死患者的应用价值.方法 收集我院14例脑梗死患者,行常规MRI和DWI、DSC、PCASL检查.以DWI显示的梗死灶和镜像对照区为ROI,分别测量其局部脑血流量(rCBF),并计算梗死灶和镜像对照区的信号强度比(rCBF梗死灶/rCBF镜像对照区),测量双侧额叶、颞叶、顶叶、枕叶、小脑的rCBF,并进行统计学分析.结果 PCASL和DSC检出梗死灶的灌注改变一致,rCBF梗死灶/rCBF镜像对照区差异无统计学意义.患者双侧额叶、颞叶、顶叶、枕叶、小脑皮层非梗死区的PCASL与DSC测得的rCBF均有良好的相关性(P <0.05).结论 PCASL是一种安全无创的脑血流测量技术,可有效显示梗死灶的血流灌注改变;并与DSC所测的各脑叶rCBF有良好的相关性.  相似文献   

10.
目的:探讨动脉自旋标记成像(ASL)及弥散加权成像(DWI)两种磁共振成像方法在急性缺血性脑血管病诊断中的价值.材料与方法:通过GE HDx 1.5T双梯度磁共振,对22例急性脑缺血患者分别行常规MR(包括T1FLAIR、T2WI)、3D-TOF MRA、DWI(b值取1000s/mm^2)及3D ASL序列,观察ASL与DWI序列病变区最大层面面积的大小及与MRA之间的关系,并进一步测量缺血区域与对侧镜像层面的脑血流(CBF)值,计算相对脑血流值(rCBF)=缺血区域CBF/对侧镜像层面CBF,rCBF在0.9-1.1之间,定义为灌注正常,rCBF> 1.1定义为高灌注,rCBF<0.9定义为低灌注.结果:22例急性脑缺血患者中,小面积缺血10例,DWI表现为斑点状或小片状高信号,其中4例ASL为低信号,DWI面积与ASL面积相近,另6例DWI显示为高信号,ASL无阳性表现,小面积梗死病例中MRA均无明显异常;大面积缺血10例,DWI表现为一个供血区大片状高信号或多个供血区域斑点状、小片状高信号,ASL均为低信号,ASL显示病变区最大层面面积大于DWI面积,其中2例病变周围皮层区ASL存在局部高信号影,大面积缺血病例中MRA存在不同程度的脑动脉硬化或动脉闭塞;另2例患者DWI表现为阴性,而ASL为低信号,即TIA患者,MRA显示1例表现为大脑中动脉硬化,1例表现为颈内动脉闭塞.对于6例ASL为阴性病例者,缺血区CBF值为(40.47±1.94) ml/100g* min,对侧镜像区为(42.74±1.49) ml/100g* min,rCBF为0.95±0.04;16例ASL表现为低信号的病例,其中1例DWI表现为脑干及双侧小脑半球局部高信号,ASL表现为双侧小脑半球均为低信号,两侧CBF分别为24.13 ml/100g* min、23.76 ml/100g* min,因为无法测量该患者正常小脑CBF值,从而无法计算rCBF,本例患者MRA表现为椎基底动脉及双侧大脑后动脉闭塞;其余15例病例测量病变区CBF值为:(22.29±0.95) ml/100g* min,对侧镜像层面CBF为:(44.96±2.89) ml/100g* min,rCBF为0.52±0.03,局?  相似文献   

11.
Objective: To identify patterns of nonfatal and fatal penetrating trauma among children and adults in New Mexico using ED and medical examiner data.
Methods: The authors retrospectively sampled in 5-year intervals all victims of penetrating trauma who presented to either the state Level-1 trauma center or the state medical examiner from a 16-year period (1978–1993). Rates of nonfatal and fatal firearm and stabbing injury were compared for children and adults.
Results: Rates of nonfatal injury were similar (firearm, 34.3 per 100,000 person-years; stabbing, 35.1). However, rates of fatal injury were significantly different (firearm, 21.9; stabbing, 2.7; relative risk: 8.2; 95% confidence interval: 5.4, 12.5). From 1978 to 1993, nonfatal injury rates increased for children (p = 0.0043) and adults (p < 0.0001), while fatal penetrating injury remained constant. The increase in nonfatal injury in children resulted from increased firearm injury rates. In adults, both stabbing and firearm nonfatal injury rates increased.
Conclusions: Nonfatal injury data suggest that nonfatal violence has increased; fatal injury data suggest that violent death rates have remained constant. Injury patterns vary by age, mechanism of trauma, and data source. These results suggest that ED and medical examiner data differ and that both are needed to guide injury prevention programs.  相似文献   

12.
ABSTRACT

The Cochrane Library of Systematic Reviews is published quarterly as a DVD and monthly online. The January 2011 issue (first quarterly DVD for 2011) contains 4515 complete reviews, 1985 protocols for reviews in production, and 13,521 one-page summaries of systematic reviews published in the general medical literature. In addition, there are citations of 641,000 randomized controlled trials, and 14,018 cited papers in the Cochrane methodology register. The health technology assessment database contains over 9300 citations. One hundred and seven new reviews have been published in the last 3 months, of which five have potential relevance for practitioners in pain and palliative medicine.  相似文献   

13.
14.
Three supplementary perspectives are presented arguing that interprofessional collaboration is both necessary and desirable. Nonetheless, there are often too many serious intra-professional barriers and obstacles to interprofessional collaboration to make it successful. Some of these barriers, it is argued and illustrated, are found in the multiple ways in which professional identity is tacitly acquired and embodied in the practitioners' habitual, everyday practice. The paper then explores ways in which reflection, especially Second order reflection, can help to elucidate and overcome these obstacles, as well as increasing professional adaptability and competence.  相似文献   

15.
Ankle sprains are the most common injury of the musculoskeletal system and are associated with significant societal and economic impacts. It has been proven that classical therapeutic strategies may not be effective in preventing recurrent injuries: the recurrence rates reported in the literature can reach 73%. In order to provide an effective rehabilitation solution, a destabilizing orthosis was developed. This device is equipped with a mechanical articulator reproducing the subtalar mechanics and placed under the heel. In this paper, we present the main results of a preliminary clinical study conducted between 2004 and 2007. All subjects included in this study were treated with the abovementioned orthosis during 10 rehabilitation sessions of 30 minutes each. Data show a relatively low recurrence rate of 12% for the overall population. Moreover, it's of primary importance to note that this satisfactory ratio is largely reduced (3% of recurrence rate) for the 29 patients who performed one training session per month after the 10th initial rehabilitation sessions. Hence, the destabilizing orthosis appears to be an effective solution to prevent recurrent ankle sprains. However, joint protection requires long-term and regular training sessions. This result has motivated the development of a similar device allowing patients to perform training sessions at home. Finally, data obtained in this study are promising awaiting the final results of the comparative, multicentric and independent clinical trials currently managed by the Hospices Civils de Lyon.  相似文献   

16.
This is a new method for the determination of creatine kinase isoenzyme MB activity in serum. The method uses direct activity measurement of creatine kinase B subunit activity after blocking of CK-M subunit activity by inhibiting antibodies. The test takes no longer than 15 min. The method yields an intra-serial C.V. of 2.0-12.9%, and a C.V. from day to day of 5.5%. The detection limit is 3.4 U/l creatine kinase MB. In the 95 cases with proven myocardial infarction several types of creatine kinase MB activity kinetics could be determined. The percentage of creatine kinase MB of peak CK-total is 6-25%, with a mean of 11.1%. The amount of creatine kinase MB with respect to total CK activity after reinfarction is higher than the amount after initial infarction.  相似文献   

17.
目的 探讨俯卧位通气对高海拔地区肺复张术(RM)治疗无效急性呼吸窘迫综合征(ARDS)患者的治疗作用.方法 从海拔2260m的地区医院筛选RM治疗无效的41例ARDS患者[平均氧合指数( PaO2/FiO2)较RM前升高<20%视为RM无效],依不同病因分为肺内源性ARDS组(ARDSp组)和肺外源性ARDS组(ARDSexp组),每组再按信封法随机分为俯卧位组和仰卧位组,即ARDSp俯卧位组(11例)、ARDSp仰卧位组(9例)、ARDSexp俯卧位组(10例)、ARDSexp仰卧位组(11例).在通气前及通气1、2、3、4h监测动脉血氧分压( PaO2)、PaO2/FiO2、静态顺应性(Cst)、气道阻力(Raw)的变化.结果 通气lh时,ARDSexp俯卧位组PaO2/FiO2( mm Hg,l mm Hg=0.133 kPa)即较通气前显著升高(157.4±40.6比129.3±48.7,P<0.05),并随通气时间延长呈持续增高趋势,4h达峰值(219.1 ±41.1);且ARDSexp俯卧位组通气3h内PaO2/FiO2较其他3组显著增高,另3组间则差异无统计学意义.ARDSp俯卧位组、ARDSexp俯卧位组通气4h时PaO2/FiO2均较相应仰卧位组显著增高(208.8±39.7比127.4±47.1,219.1±41.1比124.9±50.8,均P<0.05).4组通气前后Cst无显著改变,各组间差异也无统计学意义.ARDSp俯卧位组通气4h时Raw(cmH2O·L-1·s-1)较通气前显著降低(6.8±1.7比10.7±1.8,P<0.05),且明显低于其他3组;其他3组各时间点Raw组内及组间比较差异均无统计学意义.结论 俯卧位通气作为ARDS机械通气重要策略之一,可以改善RM无效高原ARDS患者的氧合,为抢救患者赢得宝贵的时间.  相似文献   

18.
The Department of Veterans Affairs (VA) in the USA operates a network of 172 medical centres which all utilize a hospital information system (HIS) which has been developed and is currently maintained by the VA. During the past several years, an image management and communication module has been developed, installed and clinically utilized at the Washington DC and Maryland VA Medical Centres. This image management and communication system, referred to as the decentralized hospital computer program (DHCP) imaging system, is fully integrated with a commercial picture archiving and communication system (PACS). The system is utilized to capture, archive, and display all images generated within the hospital including radiology, nuclear medicine, pathology, endoscopy, bronchoscopy, and dermatology, intraoperative photographs, ECG data, and a limited number of paper documents. The ultimate goal of the project is to have all patient text and image data available at any clinical workstation to any authorized user anywhere within the network of medical centres. Clinical requirements for an imaging workstation include ease of use, rapid and reliable access to the complete set of patient information, and images which are of acceptable quality to meet the requirements of the user and the subspecialty. Patient confidentiality and data security must be safeguarded at all times. Integration of the images with the remainder of the patient's database was found to be critical to the success of the project. The experience at the Washington and Maryland facilities suggests that an imaging system that is successfully integrated with a hospital information system can provide substantial clinical and economic benefits both within and among medical centres. Clinical acceptance and utilization of the system has been excellent, particularly in diagnostic radiology where DHCP Imaging has been interfaced to a commercial PAC system. Based upon this initial experience, the VA has begun to deploy the system throughout its large network of medical centres.  相似文献   

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Myocardial elastography is a novel method for noninvasively assessing regional myocardial function, with the advantages of high spatial and temporal resolution and high signal-to-noise ratio (SNR). In this paper, in-vivo experiments were performed in anesthetized normal and infarcted mice (one day after left anterior descending coronary artery [LAD] ligation) using a high-resolution (30 MHz) ultrasound system (Vevo 770, VisualSonics Inc., Toronto, ON, Canada). Radiofrequency (RF) signals of the left ventricle (LV) in longitudinal (long-axis) view and the associated electrocardiogram (ECG) were simultaneously acquired. Using a retrospective ECG gating technique, 2-D full field-of-view RF frames were acquired at an extremely high frame rate (8 kHz) that resulted in high-quality incremental displacement and strain estimation of the myocardium. The incremental results were further accumulated to obtain the cumulative displacements and strains. Two-dimensional and M-mode displacement images and strain images (elastograms), as well as displacement and strain profiles as a function of time, were compared between normal and infarcted mice. Incremental results clearly depicted cardiac events including LV contraction, LV relaxation and isovolumetric phases in both normal and infarcted mice, and also evidently indicated reduced motion and deformation in the infarcted myocardium. The elastograms indicated that the infarcted regions underwent thinning during systole rather than thickening, as in the normal case. The cumulative elastograms were found to have higher elastographic SNR (SNR(e)) than the incremental elastograms (e.g., 10.6 vs. 4.7 in a normal myocardium, and 6.0 vs. 2.4 in an infarcted myocardium). Finally, preliminary statistical results from nine normal (m = 9) and seven infarcted (n = 7) mice indicated the capability of the cumulative strain in differentiating infracted from normal myocardia. In conclusion, myocardial elastography could provide regional strain information at simultaneously high temporal (>/=0.125 ms) and spatial ( approximately 55 microm) resolution as well as high precision ( approximately 0.05 microm displacement). This technique was thus capable of accurately characterizing normal myocardial function throughout an entire cardiac cycle, at the same high resolution, and detecting and localizing myocardial infarction in vivo.  相似文献   

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