鼻腔及鼻窦冠状扫描时头架角度控制及成像研究

目的探讨仰卧式头架螺旋CT鼻腔及鼻窦冠状位扫描时机器摆动角度范围对冠状成像质量的影响.材料与方法对1999年8月～2000年10月门诊及住院患者117例行鼻腔及鼻窦冠状位扫描,采用仰卧式头架,对一些病例采用近似冠状位扫描,将所有图像均进行三维重建.结果与OML成67°～90°的近似冠状位扫描基本能满足依赖冠状位鼻腔及鼻窦CT图像诊断的需要.结论近似冠状位扫描在某些情况下是切实可行的扫描方法.     

CT图像脑干伪影的形态与密度研究

伪影是指被扫描物体中并不存在而在图像中却显示出来的各种不同的影像。ＣＴ图像中后颅窝常见各种形态的伪影,其中出现在脑干的伪影一般称之为亨氏暗区,本文旨在分析脑干伪影的形态、密度及产生机制,并予以分类,探讨减少伪影的方法,为放射医生阅ＣＴ片及诊断提供依据...     

小儿髓母细胞瘤与室管膜瘤的术前误诊分析

儿童颅内肿瘤好发于中线部位和后颅凹,早期即可压迫脑室系统,影响脑脊液循环而致颅内压增高,压迫脑干等主要结构,故病情重,病程短。后颅窝肿瘤由于有颅底颅骨伪影干扰,CT影像又仅限于横轴位扫描,往往造成后颅窝肿瘤的鉴别诊断困难,而造成术前误诊[1]。本文回顾分析一组儿童后颅     

CT影像叠加技术检查颅底病变的应用效果分析

目的:针对颅底病变患者评价CT影像叠加技术检查的应用效果。方法:将我院2018年4月—2019年4月收录的46例患者进行研究,皆实施常规CT检查与CT影像叠加技术检查,以病理诊断结果作为该研究的参照标准,评价应用效果。结果:46例颅底病变患者中,经CT影像叠加技术扫描共出现线性伪影4例(8.70%),伪影过多7例(15.22%),伪影少35例(76.09%),经常规C T扫描共出现线性伪影13例(28.26%),伪影过多33例(71.74%),伪影少0例(0.00%),表明C T影像叠加技术扫描的对患者脑组织的显示效果更好,能够为临床诊断提供更清晰的图像数据。结论:通过CT影像叠加技术检查能够为颅底病变的诊断提供科学的图像数据支持,值得在基础医院推广。     

在头颈CT检查中运用金属伪影去除技术对去除口腔内金属伪影的效果分析

目的:探讨分析在头颈CT检查中应用O-MAR技术对于去除口腔内金属伪影的应用效果。方法:选取我院2017年1月-2019年6月收治的64例行头颈CT血管造影检查同时口腔中含有钛金属补牙材料患者作为研究对象,按照图像处理技术分成两组,各32例。实验组扫描后图像通过O-MAR技术进行处理,对照组扫描后图像通过常规技术进行处理。对比两组患者的ROI SD值、图像质量。结果:实验组患者的图像质量显著优于对照组;两组ROI SD值对比差异显著,P<0.05。结论:在头颈CT检查中应用O-MAR技术能够帮助降低高原子序数伪影对于图像的不良影响。     

螺旋CT在脑干出血诊断中的应用

目的介绍螺旋CT的一些特殊功能在脑干出血诊断中的应用，并评价其价值。方法回顾分析2002年12月至2004年2月做CT检查的50例脑血管意外患者资料。结果所有患者都有脑干出血的临床表现。30例行常规CT平扫，发现脑干出血5例；20例行颅底薄层螺旋扫描并做二维、三维重建后处理，发现脑干出血15例。结论在对后颅凹区脑干出血诊断中，采用薄层螺旋扫描并做二维、三维重建后处理，可减少伪影干扰；提高出血灶检出率，比常规平扫具有较大优越性。     

CT机时间分辨力的体模测试方法

目的 设计用于测量CT机时间分辨力的方法和相应体模。方法 根据环形伪影产生原理,使含有高密度衰减物的自制时间分辨力均匀体模与CT机架以同样的速度旋转,产生环形伪影,根据环形伪影的角度测量CT机的时间分辨力。结果 当CT机架以0.5 s/240°的扫描速度采集数据时,用自制体模测得CT机的时间分辨力为(0.5002±0.0014)s。结论 实验设计的方法和自制体模可用于测量CT机的时间分辨力。     

低剂量迭代重建技术CT扫描检查颅脑外伤临床观察

目的观察低剂量迭代重建技术(i Dose)CT扫描检查颅脑外伤的临床价值。方法选择2014年1月~2015年6月在我院接受治疗的颅脑外伤患者90例作为研究对象,随机分成3组,各30例。A组:常规剂量滤波反投影法;B组:i Dose法(2/3剂量);C组:i Dose法(1/2剂量)。比较3组的图像质量,对比3组的CNR、SNR和图像噪声以及辐射剂量情况。结果 A组和B组在图像质量的图像主观噪声评分、病变显示评分、灰白质对比评分以及颅底伪影评分上比较,差异无统计学意义(P0.05);C组的图像主观噪声评分、病变显示评分、灰白质对比评分以及颅底伪影评分方面略差于A组和B组,差异具有统计学意义(P0.05);A组的噪声评分低于B、C组,CNR、SNR水平则高于B、C组,差异具有统计学意义(P0.05);A组的DLP和CTDIvol明显高于B组和C组,差异具有统计学意义(P0.05)。结论低剂量迭代重建技术CT扫描检查颅脑外伤可以显著降低辐射剂量,可有效显示病变情况,虽然噪声相对较大,但是其图像质量满足临床诊断要求,具有较高的应用价值。     

低剂量头颅CT扫描最佳迭代算法(ASIR-V)权重的初探

目的初探头颅低剂量扫描中最佳Post-ASIR-V的权重。方法前瞻性选取头颅CT检查中的体检患者60例,随机分为A、B两组:A组(对照组)扫描参数为120 kVp、管电流280 mA、轴扫、准直器宽度120 mm、转速1.0 s/r;B组(实验组)扫描参数为100 kV、管电流280 mA、前置Pre-ASIR-V为0%、轴扫、准直器宽度120 mm、转速1.0 s/r。A组用FBP重组,B组Post-ASIR-V重组权重分别为:0%、20%、40%、60%、80%、100%,A、B重组层厚均为1.25 mm。测量后颅窝层面、基底节区层面和半卵圆中心层面脑实质的CT值、SD值,计算SNR=CT/SD。记录CT容积剂量指数,剂量长度乘积(DLP)并计算有效辐射剂量(ED),计算公式为ED=DLP×k,k=0.0021 mSv/(mGy·cm),采用单因素方差分析进行客观评价。主观评价:由2名高年资医师采用双盲法对CT图像质量进行主观评价。图像质量评价标准(三分法):3分为图像质量较好,无明显伪影;2分为图像有少许伪影但不影响诊断;1分为图像有严重伪影。采用Kappa对两名医生进行一致性进行评价,秩和t检验对主观评价进行统计学分析。结果随着Post-ASIR-V权重由0%～100%,SD值逐渐降低,SNR逐渐增加,且各组间差异具有统计学意义(P0.05);Post-ASIR-V权重在60%时,图像质量最佳;B组辐射剂量较A组降低了34.31%。结论采用100 kV低剂量头颅扫描,Post-ASIR-V 60%重组权重图像质量最佳,并满足临床诊断。     

不同密度口服阳性对比剂对PET/CT图像质量及标准摄取值的影响

目的探讨不同密度口服阳性对比剂对PET/CT图像质量和标准摄取值(SUV)的影响。方法60例PET/CT显像患者,显像前常规口服浓度为2%的泛影葡胺1000ml,其中14例患者肠道内发现多处高密度残留钡剂。所有患者均同时采用CT及137Cs两种衰减校正方法,分别重建CT衰减校正(CTAC)、137Cs衰减校正(CsAC)图像。选择所有患者胃肠道内泛影葡胺充盈区、无对比剂充盈区、臀部软组织区以及14例患者高密度钡剂充盈区勾划感兴趣区(ROI)。比较各感兴趣区CTAC和CsAC的平均SUV差异,以及CTAC、CsAC的图像差异。结果在所有正常软组织区、无对比剂充盈区以及泛影葡胺充盈区,CTAC和CsAC的平均SUV无显著性差异。在高密度残留钡剂充盈区,CTAC的平均SUV明显高于CsAC(t=3.451,P=0.018),其差异与CT值成正相关(r=0.445,P=0.021)。比较所有图像,正常软组织、无对比剂充盈区、泛影葡胺充盈区CTAC和CsAC图像质量无明显差异。在高密度残留钡剂充盈区,CTAC图像上可见FDG高摄取伪影,而CsAC图像为正常摄取。结论低密度口服泛影葡胺对PET/CT显像图像质量和标准摄取值无明显影响,高密度钡剂可使PET/CT的SUV明显高估,且可出现不同程度的FDG高摄取伪影。     

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.     

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.     

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.     

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.