扩散张量各向异性分数在星形细胞瘤中的诊断价值

目的评价MR扩散张量成像(DTI)各向异性分数(FA)在星形细胞瘤中的应用价值.方法经手术及病理证实的星形细胞瘤共26例,其中低级别星形细胞瘤10例,高级别星形细胞瘤16例.行常规MR 、DTI检查.构建 FA 图,并测量肿瘤、水肿区及正常白质的FA值.结果正常白质纤维在FA图上表现为高信号.低级别星形细胞瘤多呈低信号,边缘清晰,周围白质纤维呈高信号,信号未见明显减低. 高级别星形细胞瘤亦多呈低信号,边缘模糊,肿瘤实体区与水肿区FA值无显著性差异(P＞0.05);所有病例肿瘤实体区和水肿区 FA值与邻近正常脑白质进行比较,存在显著性差异(P＜0.05),即FA图不能明确区分肿瘤边缘及水肿区,但能将二者和正常白质纤维束鉴别.结论 DTI可清楚显示肿瘤与周围白质纤维的解剖关系,指导临床制定手术方案.     

DTI多参数综合分析在颅内星形细胞瘤临床分级及神经外科手术中的应用价值研究

目的：探讨DTI多参数综合分析及DTT技术在星形细胞瘤分级、术前计划制定、术后疗效评价中的应用价值。方法：星形细胞瘤患者33例,术前和/或术后行常规T1WI、T2WI、T1WI增强、DTI检查。测量病灶不同区域及对侧正常白质区的DCavg值、FA值、ADC值、1-VR值及RA值;扩散张量纤维束成像（DTT）重建病变周围脑白质纤维束。结果：各组中的病灶不同区域的各测量值均存在显著差异（P<0.05）。低级别星形细胞瘤肿瘤周围的白质纤维束多呈推挤水肿改变,2例患者术后白质纤维束移位水肿减轻,预后良好,而高级以浸润破坏为主, 3例患者术后无改善。结论：DTI多参数均有助于区分肿瘤不同区域,有助于低、高级别星形细胞瘤的鉴别;DTI及DTT有助于肿瘤患者术前计划的制定和手术效果的评价。     

DTI联合IVIM-DWI技术对脑胶质瘤分级的诊断价值

目的:联合应用磁共振扩散张量成像(DTI)和体素内不相干运动扩散加权成像(IVIM-DWI)对脑胶质瘤进行分级诊断,评估其临床应用价值。方法:收集2017年6月-2019年3月共42例临床高度怀疑胶质瘤的患者,术前均未进行放化疗及其他抗肿瘤干预,均行多模态MRI扫描及DTI和IVIM-DWI成像,汇总影像资料,测量DTI各向异性指数FA值、平均扩散系数MD值;IVIM微循环灌注系数D*值、真性水分子扩散系数D值、灌注分数f值,通过DTI-Fibertrak纤维束示踪成像技术后处理脑内白质纤维束。追踪外科手术及预后情况的完整治疗记录,最后将术前影像诊断结果与术后病理学结果对照分析。结果:42例患者低级别胶质瘤19例(LGG,WHOⅠ~Ⅱ级),高级别胶质瘤23例(HGG,WHOⅢ~Ⅳ级),其中II级19例、III级14例、IV级9例。利用IVIM-DWI和DTI技术,HGG灌注系数D*值高于LGG,HGG扩散系数D值及灌注分数f值均低于LGG,HGG所有FA值、MD值均低于LGG,以上差异均有统计学意义(P<0.05)。DTI的白质纤维束成像对胶质瘤瘤体内的纤维束破坏、边界及外周侵袭范围、与功能区关系可进行明确区分。结论:DTI联合IVIM-DWI成像技术,对于胶质瘤能够进行分级诊断,并且对术前评估、治疗方案选择均具有指导意义和重要的临床应用价值。     

脑灰质异位磁共振扩散张量成像的定量研究

目的：探讨脑异位灰质及其周边白质纤维束在磁共振扩散张量成像中的影像特点。方法：回顾性分析10例经MRI证实的脑灰质异位患者DTI图像。观察DTI及DTT图像灰质异位区周围脑白质形态,并在DTI图像上测量异位灰质及其周围脑白质、对侧脑白质及正常位置脑灰质各向异性分数（FA）值,比较异位灰质区脑白质与对侧大脑半球相同位置脑白质是否有统计学差异,并比较异位灰质区与正常位置灰质是否有统计学差异。结果：10例患者中Ⅰ型室管膜下型灰质异位有2例;Ⅱ型皮层下灰质异位有5例;Ⅲ型带状性灰质异位有1例;兼有上述两种或两种以上又出现Ⅳ型即混合型有2例。异位灰质区脑白质走行发生异常,呈受压推移或聚拢改变,无消融;异位灰质区脑白质与对侧大脑半球相同位置脑白质区的FA值间的差异无统计学差异（T=-0.435,P=0.669）;异位灰质区与正常位置灰质间的FA值大致相同（T=-0.000,P=1.000）。结论：异位灰质区白质纤维束形态发生改变,FA值与对侧白质纤维束相比,无明显下降;DTT可清晰显示异位灰质区脑白质的走行方向及形态。     

结合fMRI与DTI在脑胶质瘤诊治中的初步应用

目的：探讨DTI在脑胶质瘤定性、定级诊断中的作用,并尝试联合应用fMRI与DTI技术进行脑肿瘤术前定位及术中导航。方法：对18例脑胶质瘤患者进行常规T1WI、T2WI扫描及DTI、fMRI功能成像,测量肿瘤的实质部分、坏死或囊变区以及瘤周水肿区域的ADC值、FA值等参数。采用SPM软件对fMRI图像数据进行处理和统计分析,观察运动功能激活区、重要白质纤维束与颅内肿瘤病灶之间的相互关系。结果：高级别胶质瘤实体部分ADC值明显低于低级别胶质瘤,而FA值明显高于低级别胶质瘤,两者之间有显著性差异。高、低级别胶质瘤实质部分ADC值的分界点为1.21×10-3mm2/s,FA值分界点为0.17。联合应用fMRI与DTI可全面观察脑运动或视觉等重要功能激活区、重要白质纤维束与颅内肿瘤病灶之间的相互关系。结论：应用DTI可以在术前对胶质瘤进行分级,将fMRI与DTI功能影像应用于脑肿瘤导航手术可为术前计划提供必要信息,在术中避免损伤脑功能区及锥体束等重要结构,为手术提供双重保障。     

多形性胶质母细胞瘤MR弥散张量成像应用研究

目的本研究旨在探讨平均扩散系数（ADC）和各向异性指数（FA）在鉴别多形性胶质母细胞瘤肿瘤组织、水肿及正常脑组织,以及探讨ADC值及FA值在对肿瘤浸润范围中的作用。方法14例多形性胶质母细胞瘤在治疗前行常规MRI、增强扫描及弥散张量成像（DTI）,在T1WI增强、T2WI上确定肿瘤组织、水肿及正常脑组织,在ADC图和FA图上测量这些区域的FA值及ADC值,用方差分析评定值之间的差异。结果肿瘤囊变区的ADC值（2.07&#177;0.631）&#215;10^-3mm^2/s最高,其次为水肿区（1.39&#177;0.164）&#215;10^-3mm^2/s、肿瘤强化中心（1.13&#177;0.187）&#215;10^-3mm^2/s、肿瘤强化边缘（1.04&#177;0.254）&#215;10^-3mm^2/s、瘤周正常白质区（0.779&#177;0.088）&#215;10^-3mm^2/s、对侧正常白质（0.748&#177;0.082）&#215;10^-3mm^2/s。对侧正常白质FA值最高（0.538&#177;0.084）&#215;10^-3mm^2/s,肿瘤囊变区最低（0.09&#177;0.028）&#215;10^-3mm^2/s。肿瘤强化边缘与囊变坏死区、水肿区、瘤周正常白质以及对侧正常白质ADC值差别均具有显著性意义（P〈0.05）,瘤周正常白质区与对侧正常白质区ADC值无显著性意义（P〉0.05）。肿瘤强化边缘与囊变坏死区、瘤周正常白质区、对侧正常白质区FA值差别均具有显著性意义（P〈0.05）,瘤周正常白质区与对侧正常白质区FA值有显著性意义（P〈0.05）,肿瘤强化边缘FA值与水肿区FA值差异无显著性意义（P〉0.05）。结论ADC值可用于区分多形性胶质母细胞瘤正常脑白质、水肿和肿瘤强化边缘,FA值对于组织学鉴别无明显意义,FA值对肿瘤浸润范围有重要的意义。     

扩散张量成像及扩散张量纤维束成像在星形细胞瘤与脑膜瘤诊断中的价值

目的 探讨DTI及扩散张量纤维束成像(DTT)诊断星形细胞瘤与脑膜瘤的价值。方法 对22例经病理证实的脑肿瘤患者(不同级别星形细胞瘤12例,良性脑膜瘤10例),测量肿瘤实质区与健侧正常脑组织的平均ADC值和FA值,比较测值,并观察两种脑肿瘤对白质纤维束的影响。结果 星形细胞瘤及脑膜瘤患者肿瘤实质区FA值均较健侧正常脑组织降低(P均<0.05);星形细胞瘤患者肿瘤实质区ADC值较健侧正常脑组织高(P<0.05),脑膜瘤患者肿瘤实质区ADC值与健侧正常脑组织差异无统计学意义(P>0.05)。星形细胞瘤与脑膜瘤患者比较,肿瘤实质区ADC值、FA值差异有统计学意义(P均<0.05)。在DTT图中,星形细胞瘤多数表现为纤维束部分中断、受压、偏移或变形、移位;脑膜瘤纤维束呈现为稀疏、移位。结论 测量肿瘤实质区ADC值和FA值可鉴别脑内和脑外肿瘤如星形细胞瘤与脑膜瘤。DTT可清晰显示脑肿瘤对白质纤维束浸润、破坏和推移,有利于术前制定手术方案。     

扩散张量成像观察脊髓压迫症

目的 探讨采用3.0T MR研究亚急性及慢性脊髓压迫症(SCC)DTI及纤维束示踪(DTT)技术的可行性及临床应用价值.方法 采用单次激励自旋回波平面回波成像对42例SCC患者(SCC组)及49名健康志愿者(正常对照组)行3.0T MR脊髓DTI.采用ROI法分别测量正常对照组的颈髓及下段胸髓的ADC和FA值及SCC病变部位受压脊髓的ADC及FA值.根据T2WI脊髓内有无高信号将SCC组分为SCC-HI和SCC-nHI亚组.统计学分析采用单因素方差分析.利用纤维束示踪软件重组脊髓纤维束.结果 正常对照组脊髓各节段扩散定量值(ADC和FA值)差异无统计学意义;SCC-HI组与正常对照组扩散定量值间比较,病变脊髓ADC值增高(P＜0.05),FA值减低(P＜0.05);SCC-nHI与正常对照组间差异无统计学意义(P＞0.05).在DTT彩色编码图上,正常脊髓纤维束为头尾向的一束,显示了头尾侧的各向异性.SCC则表现为脊髓纤维束不同程度受压改变而无明显的破坏.结论 DTI和DTT是一种显示脊髓纤维束及其病变的有效方法,在临床中能为SCC患者的研究提供重要信息.     

扩散张量成像在颅内占位性病变中的应用研究

目的:评价MRI扩散张量成像在颅内占位性病变中的应用价值。材料与方法:经手术及病理证实的星形细胞瘤、脑膜瘤、垂体瘤、转移瘤及脑脓肿共46例。行常规MRI扫描、扩散张量成像(DTI)检查。构建各向异性分数(FA)图,并测量病变及周围白质的FA值。结果:正常白质纤维在FA图上表现为高信号。肿瘤多呈低信号。在肿瘤存在时,周围白质纤维可表现为受推压移位或浸润破坏,破坏后FA值降低,表现为低信号。脓肿多呈低信号,其内部若有尚未破坏的白质纤维存在,可呈高信号。这些表现在常规MRI图像上均未清楚显示。结论:DTI可清楚显示占位性病变与周围白质纤维的解剖关系,指导临床制定手术方案。     

3.0T 1H-MRS及DTI诊断脑胶质瘤: AA值与FA值的相关性

目的 探讨脑胶质瘤肿瘤外周至肿瘤中心3.0T磁共振氢质子波谱(¹H-MRS)的N-乙酰天门冬氨酸(NAA)值及弥散张量成像(DTI)的各向异性(FA)值的相关性,评价¹H-MRS及DTI对脑胶质瘤的诊断价值。方法 回顾性分析经组织病理学证实的9例低级别(Ⅰ~Ⅱ级)胶质瘤、16例高级别(Ⅲ~Ⅳ级)胶质瘤的常规MRI、DTI及¹H-MRS资料,分析肿瘤不同感兴趣区的部分FA值、NAA与肌酸(Cr)比值、胆碱(Cho)与肌酸(Cr)比值及胆碱(Cho)与NAA的比值,并观察NAA值与FA值的相关性。结果 从肿瘤中心到外周(包括肿瘤邻近脑白质和对侧大脑半球白质)FA和NAA数值持续升高,且两者呈正相关(r=0.90,P<0.05)。低级别、高级别胶质瘤组瘤体的NAA/Cr无明显差异,FA、Cho/Cr和Cho/NAA差异均有统计学意义(P均<0.05)。结论 脑胶质瘤中,从肿瘤外周至肿瘤中心脑胶质瘤对周围组织的浸润程度逐渐增加,而NAA值及FA数值表现为降低趋势,反映了神经元结构和白质纤维的完整性的破坏。肿瘤中心FA、Cho/Cr和Cho/NAA数值对鉴别低级别、高级别胶质瘤具有一定意义。     

Guns and Knives in New Mexico: Patterns of Penetrating Trauma, 1978–1993

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.     

Interprofessional approaches to creating safe,high quality health care

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.     

Systematic Reviews Published in the January 2011 Issue of The Cochrane Library

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.     

Prospects for the control of neglected tropical diseases by mass drug administration

The prospects for the control of neglected tropical diseases, including soil-transmitted helminthiasis, shistosomiasis, lymphatic filariasis, onchocerciasis and trachoma, through mass drug administration, are exemplified by the elimination of the trachoma as a public-health problem in Morocco. In spite of this and other striking successes, mass drug administration programs are faced with major challenges resulting from suboptimal coverage and lack of efficacy. At current suboptimal coverage rates, programs may need prolongation for an extended period, increasing costs and undermining sustainability. Community participation through health education and information appears to be crucial to improve coverage and to achieve sustainability. Implementation of complementary measures, such as vector control, improved hygiene and environmental sanitation, are important to further control transmission and to prevent re-emergence of the infection and, again, may only be achieved effectively through community-based initiatives. To reduce costs and to relieve pressure on the health system, combining neglected tropical disease programs in areas where diseases coexist and integration with existing control programs for malaria, tuberculosis and HIV/AIDS is advocated. The risk of developing drug resistance is of particular concern in view of the lack of alternative drugs, and reduced treatment efficacy due to emerging resistance is evident for the soil-transmitted helminths and onchocerciasis. Given the risk for the development of drug resistance and the need for a high degree of participation, close attention should be paid to the monitoring of the coverage and efficacy of the different program components.     

Bacterial meningitis: an update of new treatment options

The outcome of bacterial meningitis critically depends on the rapid initiation of bactericidal antibiotic therapy and adequate management of septic shock. In community-acquired meningitis, the choice of an optimum initial empirical antibiotic regimen depends on the regional resistance patterns. Pathogens resistant to antibacterials prevail in nosocomial bacterial meningitis. Dexamethasone is recommended as adjunctive therapy for community-acquired meningitis in developed countries. In comatose patients, aggressive measures to lower intracranial pressure <20 mmHg (in particular, external ventriculostomy, osmotherapy and temporary hyperventilation) were effective in a case–control study. Although many experimental approaches were protective in animal models, none of them has been proven effective in patients. Antibiotics, which are bactericidal but do not lyse bacteria, and inhibitors of matrix metalloproteinases or complement factor C5 appear the most promising therapeutic options. At present, vaccination is the most efficient method to reduce disease burden. Palmitoylethanolamide appears promising to enhance the resistance of the brain to infections.     

Prise en charge des entorses externes de cheville : étude clinique préliminaire sur l’efficacité du dispositif Myolux™

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.     

Imaging choices in occult hip fracture

Background: Hip fracture is a common injury, with an incidence rate of > 250,000 per year in the United States. Diagnosis is particularly important due to the high dependence on the integrity of the hip in the daily life of most people. Objectives: In this article we review the literature focused on hip fracture detection and discuss advantages and limitations of each major imaging modality. Discussion: Plain radiographs are usually sufficient for diagnosis as they are at least 90% sensitive for hip fracture. However, in the 3–4% of Emergency Department (ED) patients having hip X-ray studies who harbor an occult hip fracture, the Emergency Physician must choose among several methods, each with intrinsic limitations, for further evaluation. These methods include computed tomography, scintigraphy, and magnetic resonance imaging. Conclusion: We present an evidence-based algorithm for the evaluation of a patient suspected to have an occult hip fracture in the ED. Also outlined are future directions for research to distinguish more effective techniques for identifying occult hip fractures.     

Systematic Reviews Published in the April 2012 Issue of the Cochrane Library

ABSTRACT

The Cochrane Library of Systematic Reviews is published quarterly as a DVD but monthly online. The April 2012 issue (second DVD for 2012) contains 5045 complete reviews, 2182 protocols for reviews in production, and 17,084 short summaries of systematic reviews published in the general medical literature. In addition, there are citations of 674,000 randomized controlled trials, and 15,400 cited papers in the Cochrane methodology register. The health technology assessment database contains just over 11,000 citations. One hundred and seventeen new reviews have been published in the last 3 months of which 12 have potential relevance for practitioners in pain and palliative medicine. The impact factor of the Cochrane Library stands at 6.186. Readers are encouraged to access the full report for any articles of interest as only a brief commentary is provided.     

Platelets,thrombosis, coagulation,and atherosclerosis

When I first got the invitation to join a medical delegation going to Moldova, I thought for a moment that our destination was the fictional country in the old Marx Brothers movie Duck Soup. On further checking, it turns out that entertaining place was called Freedonia. I now know that Moldova is indeed a real country, bordered on the west by Romania and on the other three sides by the Ukraine. It is a proud country, rich with traditions, and its people are warm, giving, eager to learn ways to improve their healthcare system, and deeply appreciative of our attempts to help them in the task.