磁共振关节软骨成像的不同序列信号比较

目的:通过比较软骨信号噪声比(SNR)和对比度噪声比(CNR),分析临床常用的磁共振(MR)序列显示关节软骨的能力与限度。方法:选取12例成人离体膝关节标本行软骨磁共振成像(MRI)。应用的MR序列包括:①自旋回波T1加权序列(SE T1W);②快速自旋回波T2加权序列(FSE T2W);③短T1翻转恢复序列(STIR);④脂肪抑制质子密度序列(FS-PD);⑤三维脂肪抑制扰相梯度回波序列(3D-FS-SPGR);⑥重度T2加权梯度回波序列(T2*W GRE)。在股骨髁间凹中央层面上分别测量股骨髁软骨、股骨干骺端骨髓、小腿腓肠肌和背景噪声信号强度(SI),计算软骨SNR和软骨-关节液、软骨-骨髓、软骨-肌肉CNR。结果:3D-FS-SPGR和FS-PD序列软骨SNR最高(P<0.001)。结论:在目前临床应用的序列中,3D-FS-SPGR和FS-PD序列是进行软骨MRI的理想序列组合。     

髌软骨T2-mapping成像:MRI正常与退变软骨的差异

目的 探讨1.5T MRI 0级髌软骨T2值的区域差异及其与性别、年龄间的关系,以及MRI 0级软骨与退变软骨T2值的差异。 方法 对452例患者以1.5T MR系统行常规膝关节检查后,采用6回波SE序列扫描完成髌骨轴位T2-mapping成像。对髌软骨进行MRI分级,测量并比较髌软骨最厚层面内侧、外侧、全层和病变处的T2值。 结果 MRI 0级髌骨内、外侧软骨和全层软骨的T2值差异无统计学意义(P=0.15)。髌软骨全层T2值与性别无相关性。>60岁者髌软骨T2值高于其他年龄组。当髌软骨退变时,Ⅰ~Ⅳ级T2-病变均明显高于T2-对照(P<0.001),T2-病变也明显高于MR 0级髌软骨的T2值(P<0.001)。Ⅰ~Ⅳ级髌软骨病变的T2值之间差异有统计学意义(P<0.001),且T2值随病变分级升高而增加。 结论 MRI 0级髌软骨全层T2值与性别无相关性,但随年龄增长而增加。髌软骨退变时T2值随病变严重程度而明显增加。MR T2-mapping成像对诊断和监测骨关节早期病变具有很高的临床价值。     

正常腕关节3.0T MR多序列成像对比

目的比较3.0T MR多序列成像显示正常腕关节的价值。方法采用GE Signa HDxT 3.0T MR对23只健康腕关节行FSE-FS-PDW、FSE-FS-T2W、T2*GRE、MERGE冠状位扫描,分别计算腕骨间软骨、骨髓、肌肉、TFC的SNR和软骨/骨髓、肌肉/骨髓、三角纤维软骨盘(TFC)/骨髓的对比噪声比(CNR),以四点评分法分析腕关节的TFC、腕骨间软骨、月三角韧带、舟月韧带的能见度。比较各序列诸结构间的SNR、CNR及能见度。结果各序列间腕关节结构的SNR及CNR差异均有统计学意义(P均<0.001),MERGE和T2*GRE显著高于其他序列,FSE-FS-T2W均为最低;各序列两两比较,部分序列显示同一结构差异无统计学意义(P>0.05)。TFC、腕骨间软骨、月三角韧带、舟月韧带的能见度以MERGE最高,FSE-FS-PDW较高,各序列间差异均有统计学意义(P均<0.001);同一结构各序列两两比较,部分序列间差异有统计学意义(P<0.05)。结论 MERGE是显示正常腕骨间软骨、TFC以及月三角韧带、舟月韧带的优选序列,对于诊断腕关节软骨病变可能具有潜在应用价值。     

正常膝关节软骨的低场MRI表现

目的：探讨不同年龄段正常膝关节软骨在低场MRI中的表现特点。方法：对正常志愿者和膝关节无病变而存在其他相邻部位异常的患者共42例，采用0．3T磁共振扫描仪，进行SE T1WI、FSE T2WI、FIR、水脂分离成像（FatSepG）4种扫描序列的膝关节矢状位扫描。由两名放射科医师对扫描图像进行肉眼观察及软骨厚度测量、分层计数统计，再对MR图像组织分辨力进行评估。结果：16岁以前关节软骨厚度随年龄逐渐变薄，16岁以后软骨厚度无明显变化。关节软骨分层显示在不同年龄组、不同序列表现不同。结论：正常膝关节软骨的厚度和分层在不同年龄段表现不同。低场MRI能较好显示正常膝关节软骨的形态结构，为临床诊断膝关节软骨损伤提供参考依据。     

正常青少年股骨生长板软骨低场MRI表现及测量

目的正常青少年股骨生长板软骨低场MRI表现，探讨生长软骨厚度与年龄、性别、身高、和体质量的关系。方法正常膝关节60例，分为5个年龄组，用SE_T1WI、SE_T2WI、FLASH_T2WI序列行矢状面扫描。测量生长板软骨厚度。生长软骨厚度与年龄、性别、身高和体质量分别进行配对t检验和Spearman相关分析。结果低场强MR在显示生长板软骨方面，FLASH_T2WI为最佳序列。同年龄组男性生长板软骨厚度大于女性差异有统计学意义t=6．825（P〈0．05）。年龄与生长板厚度呈负相关γ=-0．87，P〈0．01。同年龄组各患者身高与生长板软骨厚度差异有统计学意义t=9．825（P〈0．05）。体质量与生长板软骨厚度无明显相关，γ=-0．17，P〉0．05。结论正常股骨生长板软骨的厚度与年龄、性别、身高、体质量有明显相关性；低场MRI能较好显示生长板软骨的形态结构和演变过程，成为评估青少年骨发育情况的重要手段。     

SPIO增强MRI对兔肝脏微小肿瘤检出的研究

目的探讨超顺磁性氧化铁(SPIO)增强MR不同序列成像对兔VX2肝微小肿瘤病灶的检出率.方法 15只新西兰大白兔肝内种植VX2肿瘤,分别在种植肿瘤后7天、14天行MR SE T1WI、FSE T2WI、GRE T2*WI、GRE T1WI平扫和SPIO增强扫描,记录不同检查序列所显示的肿瘤数目,比较显示率,确定SPIO增强MRI最佳扫描参数.结果 15只兔肝内种植VX2肿瘤后共有15个肿瘤生长,成功率100%.种植后7天肿瘤<5 mm,SPIO增强序列GRE T2*WI、GRE T1WI可显示所有的肿瘤病灶,显示率为100%,明显优于MRI平扫,SPIO增强SE T1WI及FSE T2WI序列,GRE T2*WI序列有更好的肿瘤-肝实质信号对比.14天后,肿瘤生长到1～2 cm, 除GRE T2*WI序列平扫显示率增加外,其他各检查方法对病灶的显示没有明显的差异.结论 SPIO增强MRI的GRE T2*WI、GRE T1WI序列对兔肝脏VX2微小肿瘤具有同样的高检出率,进行SPIO肝脏增强MRI检查时,GRE T2*WI序列是首选序列.     

T2^*mapping技术评估早期膝关节软骨退变

目的:探讨T2^*mapping技术诊断早期膝关节软骨退变的应用价值。方法:常规MR成像显示关节软骨正常而关节镜诊断软骨退变的65个膝关节,先记录常规MR成像显示关节软骨正常的具体关节面和数量,再记录T2^*mapping诊断为软骨退变的具体关节面和数量并与关节镜结果对照。测量软骨内退变区域T2^*值以及正常区域T2^*值,统计分析两者是否存在差异。结果:65个膝关节,关节镜诊断软骨退变113处,T2^*mapping诊断软骨退变72处,T2^*mapping诊断阳性率63.7%。软骨退变区域的T2^*均值为30±8.1ms,正常区域的T2^*均值为23±5.1ms,差异有统计学意义(t=5.585,P<0.05)。结论:T2^*mapping技术可明显提高MR术前诊断早期软骨退变的阳性率。     

膝关节软骨退变的MRI与病理对照研究

目的:通过不同MR序列对膝关节软骨病变的检出与病理进行对照比较,总结适于软骨退变的MR检查方法。材料与方法:选择尸体膝关节9只,采用7种不同的序列进行扫描,即:FS 3D FAST、FS 3D RF-spoiled FAST、3D FAST、3D RF-spoiled FAST、SE T1WI、SE T2WI、SE PDWI。将各序列发现的病变数目及分级与病理结果进行对照,所有结果采用SPSS软件包进行统计学处理。结果:FS 3D FAST及FS 3D RF-spoiled FAST发现病变的敏感度为92%和95%,均优于其它MR序列,统计学结果显示与其它各序列比较有统计学显著性差异(P<0.05),而这两个序列的扫描结果之间无统计学显著差异(P>0.05)。结论:FS 3D FAST及FS 3D RF-spoiled FAST序列是发现软骨病变的敏感序列。     

应用磁共振T2-mapping成像评价非专业马拉松运动员膝关节软骨改变

目的：应用磁共振T2-mapping成像评价马拉松普通参与者膝关节软骨厚度及软骨T2值的变化.材料与方法：对13名参加马拉松赛的健康志愿者的13个膝关节在赛前及赛后行膝关节3.0T磁共振成像,年龄24 ～40岁,平均（32±6.3）岁,应用T2-mapping成像观察和测量股骨内外髁与胫骨平台负重区及非负重区软骨浅、深层的平均T2值,同时测量各区域软骨厚度,并进行统计学分析.结果：磁共振常规序列成像示膝关节在赛前与赛后无明显变化.T2-mapping成像示关节软骨浅层T2值在赛前及赛后均高于深层,差异有统计学意义（P＜0.05）;赛后浅层软骨T2值低于赛前,差异有统计学意义（P＜0.05）;关节软骨同一区域比较,负重区软骨厚度赛后低于赛前.结论：磁共振T2-mapping成像可以量化评估关节软骨内组织成分的变化,马拉松赛前及赛后关节软骨浅层T2值均高于深层,马拉松赛后负重区软骨厚度及浅层软骨T2值减低.     

T~2*-mapping成像用于骶髂关节软骨成像的初步研究

目的:采用T2*-mapping成像定量分析正常骶髂关节(SIJ)软骨T2*弛豫时间值,探讨磁共振T2*-mapping成像用于青年健康志愿者SIJ软骨研究的可行性。材料与方法:利用T2*-mapping成像对30名青年健康志愿者行5回波GRE序列双侧SIJ斜冠状面扫描,运用T2*图测量30例骶侧软骨平均T2*弛豫时间值,并进行统计学分析。结果:30名青年健康志愿者骶侧软骨T2*弛豫时间值平均为17.15±3.26 ms。30名正常青年健康志愿者中,15名男性和15名女性骶侧软骨T2*弛豫时间值分别约为18.66±3.17 ms和15.65±2.62 ms,差异有统计学意义(t=4.005,P0.05)。30名正常青年健康志愿者中,左侧和右侧骶侧软骨T2*弛豫时间值分别约为17.26±3.51 ms和17.05±3.04 ms,差异没有统计学意义(t=0.516,P0.05)。结论:T2*-mapping成像可用于测量正常青年人SIJ骶侧软骨的T2*值,可为临床骶髂关节炎(SIS)疾病的诊断和研究提供参考。由于SIJ髂侧面软骨太薄,T2*-mapping成像应用于SIJ髂侧面软骨研究仍面临挑战。     

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.     

Clinical Pharmacokinetics of Morphine

Morphine, the most widely used mu-opioid analgesic for acute and chronic pain, is the standard against which new analgesics are measured. A thorough understanding of the pharmacokinetics of morphine is required in order to safely and effectively use this analgesic in a wide variety of patients with different levels of organ function. A MEDLINE search was conducted to identify literature published between 1966 and January 2002 relevant to the pharmacokinetics of morphine. These publications were reviewed and the literature summarized regarding unique and clinically important elements of morphine disposition relative to its parenteral administration (including intravenous, intramuscular, subcutaneous, epidural and intrathecal administration), absorption profile (immediate release, controlled release, and sublingual/buccal, and rectal administration), distribution, and its metabolism/ excretion. Special populations, including infants, elderly, and those with renal/liver failure, have a unique morphine pharmacokinetic profile that must be taken into account in order to maximize analgesic efficacy and reduce the risk of adverse events.     

Evidence-Based Pain Management and Palliative Care in Issue Four for 2009 of The Cochrane Library

ABSTRACT

The Cochrane Library of Systematic Reviews is published quarterly. Issue 4 for 2009 contains 4027 complete reviews, 1906 protocols for reviews in production, and 11447 one-page summaries of systematic reviews published in the general medical literature. In addition, there are citations of 600,000 randomized controlled trials, and 12,200 cited papers in the Cochrane methodology register. The health technology assessment database contains over 7500 citations. This edition of the Library contains 90 new reviews, of which 19 have potential relevance for practitioners in pain and palliative medicine.     

Molecular characterization of virulence and antimicrobial resistance profile of Shigella species isolated from children with moderate to severe diarrhea in northeastern Brazil

Molecular characterization of virulence and antimicrobial resistance profiles were determined for Shigella species isolated from children with diarrhea in Fortaleza, Brazil. Fecal specimens were collected along with socioeconomic and clinical data from children with moderate to severe diarrhea requiring emergency care. Shigella spp. were isolated by standard microbiological techniques, and we developed 4 multiplex polymerase chain reaction assays to detect 16 virulence-related genes (VRGs). Antimicrobial susceptibility tests were performed using disk diffusion assays. S. flexneri and S. sonnei were the predominant serogroups. S. flexneri was associated with low monthly incomes; more severe disease; higher number of VRGs; and presence of pic, set, and sepA genes. The SepA gene was associated with more intense abdominal pain. S. flexneri was correlated with resistance to ampicillin and chloramphenicol, whereas S. sonnei was associated with resistance to azithromycin. Strains harboring higher numbers of VRGs were associated with resistance to more antimicrobials. We highlight the correlation between presence of S. flexneri and sepA, and increased virulence and suggest a link to socioeconomic change in northeastern Brazil. Additionally, antimicrobial resistance was associated with serogroup specificity in Shigella spp. and increased bacterial VRGs.     

护理干预对面部中重度寻常型痤疮的临床疗效影响分析

目的研究护理干预对面部中重度寻常型痤疮的临床疗效影响。方法选取本院在2014年4月~2016年7月诊治的136例面部中重度寻常型痤疮患者,随机分为研究组与对照组,每组68例;所有患者均依据其情况给予对应的治疗,其中对照组在治疗期间给予常规护理,研究组在对照组的基础上再给予综合性护理干预,比较两组的治疗效果及护理满意度情况等。结果患者在接受治疗和护理后,研究组中度与重度患者的治疗效果较对照组均明显提高(P0.05),研究组护理满意度较对照组明显增高(P0.05)。结论对面部中重度寻常型痤疮患者在其治疗期间给予综合性护理干预,具有良好的效果。