基于中国可视化人体数据集和双源CT数据集的心脏三维可视化模型

目的 建立基于中国可视化人体(CVH)数据集和双源CT数据集的心脏三维可视化模型,并观察其特点。方法 选取中国首套可视化人体数据集心脏断面及临床双源螺旋CT心脏造影数据集,运用体绘制和面绘制的方法,在Amira 5.2.1软件上建立基于上述两种数据集的心脏三维可视化模型,并对其各自特点进行对比研究。结果 基于CVH数据集的心脏三维可视化模型在图像质量、解剖信息量、细微解剖结构显示方面优于基于双源CT数据集的心脏三维可视化模型,但基于双源CT数据集的心脏三维可视化模型在源数据获取的简便性、个体解剖特异性、细小血管显示(尤以冠状动脉细小分支明显)方面占据优势。结论 以CVH和双源CT数据集为基础构建的心脏三维可视化模型各具优劣,且相互补充,采用两种模型共同显示,可为临床提供丰富而全面的心脏三维可视化影像平台。     

厚层负间距技术用于胎儿3T MR平衡式快速场回波序列扫描

目的 评估厚层负间距平衡式快速场回波（B-FFE）序列在胎儿3T MR检查中的应用价值。方法 对91名孕妇采集胎儿头部常规层厚间距（层厚3 mm,层间距0 mm）及厚层负间距（层厚6 mm,层间距-3 mm）B-FFE序列图像,比较不同序列图像中胎儿侧脑室后角层面左侧额叶白质区（SNR_{额叶白质区}）及左侧脑室后角（SNR_{侧脑室后角}）的信噪比（SNR）、图像对比噪声比（CNR）、图像质量评分及特异吸收率（SAR）,并记录采集时间。结果 厚层负间距B-FFE序列图像的SNR_{额叶白质区}、SNR_{侧脑室后角}及CNR均高于常规层厚间距B-FFE序列图像（Z=－8.290、－8.290、－8.013,P均<0.001）,其图像质量评分高于常规层厚间距B-FFE序列图像（χ²=10.966,P=0.004）,而SAR与常规层厚间距B-FFE序列图像差异无统计学意义（Z=－0.362,P=0.717）。厚层负间距B-FFE序列图像采集时间57 s,而常规层厚间距B-FFE序列为37 s。结论 厚层负间距技术用于胎儿头部B-FFE序列扫描有助于提高图像质量,以清晰显示胎儿解剖结构及病变细节。     

3D打印技术辅助诊断和指导室间隔缺损手术

目的 探讨运用3D打印技术构建三维心脏模型对结构性心脏病诊断及治疗的可行性与临床价值。方法 基于1例室间隔缺损患儿的心脏CT影像数据,采用Mimics 17.0图形分割软件,以阈值法进行心肌分割,以动态区域生长法进行血池分割获得数字化三维心脏模型;采用PolyJet材料,以Objet500 Connex3聚合物喷射成型3D打印机打印软质的实体心脏模型,并对心脏模型进行评估。结果 3D模型可清晰显示心脏内部解剖结构、空间关系以及室间隔缺损的三维形态。在打印出的实体心脏模型上测量室间隔缺损的轴位长度为4.85 mm,与3D数字模型和CT图像中测量结果（轴位长度分别为4.86 mm和4.84 mm,矢状位长度分别为6.66 mm和6.65 mm）基本一致。结论 将3D打印技术用于结构性心脏病有助于诊断和制定适当的手术方案;通过规范化的图像处理技术获取精确的心脏模型,使个性化精准诊疗结构性心脏病成为可能。     

256层CT头部扫描iDose 4TM重建图像空间分辨性能的模体实验

目的 探讨256层Brilliance iCT头部扫描时不同扫描条件下各重建级别iDose空间分辨性能的差异。方法 采用256层Brilliance iCT和CT性能检测模体,获得头部扫描图像,以iDose和滤波反投影（FBP）两种方法进行重建,比较两种重建图像的调制传递函数（MTF）曲线之间的差异。结果 ①MTF曲线显示,同等辐射剂量条件下,相比FBP重建,iDose重建可提高1.75%~115.62%的空间分辨能力。②降低层厚会在一定程度上降低CT系统在xOy平面内的空间分辨能力。③层厚为0.9 mm时,iDose（6）的图像重建性能最好,层厚为2.5 mm时,iDose（5）的性能最好。④在保持千伏值、毫安秒及扫描层厚条件不变,螺距从0.203提高至0.391时空间分辨能力无显著差异。⑤保持毫安秒不变,同时改变管电流和扫描时间,使用iDose重建算法CT系统空间分辨能力无显著差异。结论 iDose在同等辐射剂量下能显著提高图像质量,一定程度上iDose重建图像的空间分辨力对螺距和管电流改变不敏感。为获得最佳图像质量,重建级别应与层厚相适应。     

单次激发快速自旋回波序列MR检查在正常胎儿中的应用

目的 观察单次激发快速自旋回波序列(SSFSE)在胎儿解剖结构方面的显示能力,探讨其在胎儿MR检查中的临床应用价值。方法 对14胎20周以上正常胎儿行MR检查,采用SSFSE序列对胎儿头颅、躯干行轴位、冠状位、矢状位扫描,观察胎儿各系统主要器官,包括脑、肺、心脏、肝、脾、胃肠道等的解剖和MR表现。结果 孕20周时,胎儿各主要器官均已发育。中枢神经系统:在SSFSE图像脑室系统高信号的衬托下,大脑三层结构清晰可辨,皮层及脑室旁生发层呈低信号,白质呈稍高信号。脑室系统呈生理性扩大状态,30周后脑沟、回形成逐渐明显;非神经系统:SSFSE图像肺、气管、支气管均呈高信号,胃泡、肾盂、肾盏、膀胱等空腔脏器呈高信号,肠管信号混杂,心脏、大血管、肝、脾及双侧肾脏呈等低信号。结论 SSFSE可清楚显示胎儿各主要器官的正常解剖和发育变化。     

双梯度磁共振成像质量参数的比较

目的 探讨双梯度MR成像系统常规成像序列在ZOOM和WHOLE梯度模式下的成像质量。方法 采用GE双梯度MR系统,在ZOOM和WHOLE梯度模式下对Magphan-SMR170 MR成像参数测试体模内的5个测试平面分别行SE及FSE序列扫描,比较两种梯度模式下的成像质量参数。应用Matlab 7.0软件测量和计算SNR、信号均匀性、实测层厚、层厚误差、层间距误差、几何畸变率,直接在MR显示器上读取空间分辨率数据。结果 与WHOLE梯度模式相比,SE序列成像ZOOM梯度模式下SNR及实测层厚差异有统计学意义(P均<0.05);与WHOLE梯度模式相比,FSE序列成像ZOOM梯度模式下SNR、信号均匀性、实测层厚、层间距误差、几何畸变率差异有统计学意义(P均<0.05)。结论 ZOOM梯度模式下的成像质量优于WHOLE梯度模式。临床应用中,在小FOV情况下,常规SE和FSE序列MR检查时应选择ZOOM梯度模式。     

人体个性化模型快速构建及骨骼匹配与运动仿真

目的 提出一种基于人体数据及Poser模型的人体个性化模型的建立方法,并以此实现快速骨骼匹配和运动仿真。方法 首先,采用人体MR扫描数据通过体绘制重建人体模型;其次,提取人体模型表面数据,建立OBJ格式的个性化人体三维模型,并根据个性化人体三维模型对Poser中动态模型进行尺寸修改;最后,为实现人体骨骼在运动空间的个性化匹配,提出采用层次传递参数化方法快速在局部寻找特征点及特征参数,并以此作为约束修正骨骼模型尺寸。结果 通过人体MR扫描数据,结合Poser软件,能够方便、快速地建立个性化人体体表模型并实现相应的骨骼匹配,最大程度地符合人体实际情况。通过在Poser程序中设置模型的动作姿势,能够直观地对运动状态下参数化的骨骼模型进行观察。结论 该方法可在无法得到精确人体骨骼数据时快速地对人体骨骼进行个性化匹配及可视化运动仿真,为临床医学创伤修复等领域的人体骨骼模型的建立提供一定的参考依据。     

3.0T磁共振与双源CT在经导管射频消融治疗房颤术前评估左心房与肺静脉结构的应用

目的 探讨MRI在肥厚性心肌病诊断中的应用价值。方法 经临床、超声或MRI综合评价诊断为肥厚性心肌病的患者12例,其中男10例,女2例,年龄36~53岁,平均48.6岁。所有患者均接受超声心动图和MR检查,MR检查应用SiemensAvanto1.5T扫描仪,全景成像矩阵(TIM)线圈,成像序列采用TrueFISP和HASTE序列。扫描程序包括:①定位像快速扫描:包括轴位、冠状位以及矢状面在内的三种不同方位定位像图像。②采用快速自旋回波序列,以8mm 层厚,覆盖主动脉和心脏全部的多层轴位扫描。③分别做出心脏垂直长轴位、水平长轴位和左心室流入、流出道位的定位像,并以长轴位为定位图像,扫描出短轴位图像定位。垂直长轴位图像是在轴位图像上沿心尖至二尖瓣中心的连线扫描获得平行于室间隔的长轴位图像。水平长轴位图像是在垂直长轴位图像上,沿心尖至二尖瓣中心的连线扫描获得垂直于室间隔的长轴位图像。左心室流入、流出道位以心脏短轴位近左心室基底部层面作为定位像,沿心尖、二尖瓣的中心以及主动脉瓣的中心连线扫描。④采用心脏电影成像序列,进行心脏长轴位和四腔心位不同时相扫描,以连续动态方式快电影回放;对左心室短轴位多层面进行不同时相扫描,左心室短轴位多层面扫描从二尖瓣所在的平面开始扫描至心尖。扫描层厚6~8mm,层间隔10mm。结果 所有12例患者的MR图像均明确显示心肌增厚的部位和范围,其中以心尖为主3例,室间隔为主4例,同时有心尖和室间隔增厚的4例,左心室弥漫性增厚1例。左心室收缩期显示流出道狭窄1例。牛眼图分17个节段明确显示心壁异常增厚及收缩期心肌增厚率减低部位。3例左心室射血分数严重偏高,左心室收缩末期容积指数偏低,左心室心肌厚度偏大;5例心输出量偏高,心脏指数偏高,左心室重量偏高,左心室重量指数偏高,右心室射血分数偏高,左心室部分区域心肌增厚程度偏小,左心室部分区域心肌厚度偏大;4例左心室重量指数偏高,右心室射血分数偏高,左心室部分区域心肌厚度偏大。结论 MRI可全面显示肥厚性心肌病的解剖形态、心脏局部和整体功能、左心室流入、流出道形态、左心室室壁异常增厚和收缩期增厚率减低等改变,结合心脏MR电影分析,为临床诊断、治疗提供直观、动态的心脏影像学评价信息。     

胎儿尸体MR检查替代胎儿尸体检查的可行性

目的 探讨胎儿尸体MR检查替代胎儿尸体检查的可行性。方法 对产前超声诊断胎儿畸形、并终止妊娠后的33胎行MR检查,与尸体解剖对照,分析比较产前超声结果、胎儿尸体MRI与尸体检查结果。结果 33胎中尸体检查共检出胎儿畸形42处。产前超声诊断符合率88.10%(37/42),胎儿尸体MRI诊断符合率92.86%(39/42)。 4胎心脏异常中,仅有2胎MRI结果与尸体检查符合。除外心脏结构畸形,胎儿尸体MR检查与尸体检查结果符合率为97.37%(37/38)。结论 在患者家属拒绝胎儿尸体检查时,胎儿尸体MR检查有望成为一个较好的、可被家属接受的替代选择。     

正常人十二指肠乳头低张MR成像

目的 探讨正常人十二指肠乳头的低张MRI最佳成像方法。方法 将94名志愿者随机分为低张组(n=64)和对照组(n=30)。采用χ²检验比较两组中能够清晰显示十二指肠乳头的序列的百分率,及低张组内同一扫描方位MRI不同序列、同一序列不同层厚、不同扫描方位、不同后处理重建方法以及不同b值对十二指肠乳头显示率的差异。结果 低张组中能够清晰显示十二指肠乳头的序列的百分率高于对照组(P<0.01);轴位T2WI FS、T1WI FS对于十二指肠乳头显示率差异无统计学意义(P>0.05);层厚1.5 mm轴位T1WI FS较层厚3.0 mm T1WI FS显示十二指肠乳头更佳;轴位T2WI HASTE较冠状位显示十二指肠乳头更佳(P<0.05);T1WI FS重建斜冠状位更能清晰显示十二指肠乳头全貌(P<0.05);b值800 s/mm²较b值1 000 s/mm²显示十二指肠乳头更佳(P<0.05)。结论 MR序列中轴位T1WI FS(层厚1.5 mm)、轴位及冠状位T2WI HASTE(4 mm)、T1WI FS重建斜冠状位、b值800 s/mm²DWI对十二指肠乳头及壶腹区的显示明显优于其他序列,联合低张饮水可作为十二指肠乳头首选检查组合方式。     

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.     

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.     

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.     

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.     

Determination of creatine kinase isoenzyme MB activity in serum using immunological inhibition of creatine kinase M subunit activity. Activity kinetics and diagnostic significance in myocardial infarction.

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.     

俯卧位通气对高海拔地区肺复张治疗无效急性呼吸窘迫综合征患者氧合的影响

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.     

Digital imaging among medical facilities

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.     

Myocardial elastography at both high temporal and spatial resolution for the detection of infarcts

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.