3.0T MR 上LAVA肾动脉成像的初步研究:与CEMRA对照

目的评价3.0T MR扫描仪上常规上腹部LAVA扫描动脉期图像重建对肾动脉的显示情况。方法随机选择因怀疑肝脏病变而行肝LAVA扫描的病人15例,选取动脉早期图像,在横轴位测量双肾动脉信噪比(SNR)、肾动脉与肾周脂肪的对比噪声比(CNR),将横轴位图像进行三维MIP重建。随机选择因怀疑肾动脉病变而行CEMRA检查的病人15例,在冠状位分别测量肾动脉的SNR、CNR,后进行三维MIP重建。由两位观察者单独评价两组的三维图像质量、肾动脉分支及肾静脉伪影。对测量结果和图像质量评分进行统计学处理。结果LAVA组与CEMRA组肾动脉的SNR分别为94.99±24.30和94.73±36.43;CNR分别为82.16±21.40和76.35±34.14。SNR及CNR在两组间的差异均无统计学意义(P>0.05)。LAVA组重建所得肾动脉图像达到诊断要求者:前后位66.7%;上下位93.3%。前后位观察LAVA组肾动脉图像质量低于CEMRA组,而上下位、肾静脉伪影以及肾动脉分支方面两者间无显著差异。结论LAVA序列具有较高的信噪比,而且一次扫描除了获得血管的信息外还可同时获得更多的额外信息。已行上腹部LAVA扫描者若怀疑肾动脉病变可用动脉期横轴位图像进行肾动脉重建进行初步观察。     

人工智能辅助压缩感知技术用于腰椎MRI

目的 观察人工智能辅助压缩感知(ACS)技术用于腰椎MRI的价值。方法 前瞻性纳入80例拟接受腰椎MR检查患者，随机将其均分为ACS组及对照组，每组各40例。对ACS组行基于ACS的腰椎MR扫描，对照组行常规序列扫描；比较组间图像信噪比(SNR)、对比度噪声比(CNR)及质量评分，观察ACS技术用于腰椎MR检查的价值。结果 ACS组及对照组扫描时间分别为487 s及232 s。ACS组矢状位快速自旋回波(FSE)脂肪抑制(FS)T2WI、轴位FSE T2WI和FSE FS T2WI的SNR均高于对照组(P均<0.05),组间其余序列图像SNR差异、全部序列图像CNR差异，以及图像质量评分差异均无统计学意义(P均>0.05)。结论 ACS技术用于腰椎MR检查可在保证图像质量的同时缩短扫描时间，值得临床推广。     

MRI同时多层采集技术在膝关节扫描中的应用价值

目的探讨MRI同时多层采集技术(simultaneous multi-slice,SMS)在膝关节检查中的应用价值。方法 26例志愿者分别行膝关节SMS-快速自旋回波(turbo spin echo,TSE)序列及常规TSE序列扫描,比较2种序列图像信噪比、对比噪声比及每分信噪比和图像质量定性评分,并记录扫描时间。结果 SMS-TSE矢状位T1WI、矢状位质子密度加权像脂肪抑制(proton density weighted imaging fat suppression,PDWI-FS)、冠状位PDWI-FS序列图像信噪比(50.43±15.36、132.78±17.58、109.04±6.78)均低于常规TSE序列(68.40±15.00、148.38±17.93、116.12±6.99),每分信噪比(30.57±9.31、52.69±6.97、40.39±2.51)均高于常规TSE序列(22.42±4.06、29.68±3.59、21.79±1.31)(P0.05);SMS-TSE序列对比信噪比(119.80±22.29、94.21±17.63、67.74±6.98)与常规TSE序列(123.46±23.11、96.79±20.83、67.37±6.77)比较差异无统计学意义(P0.05);2种序列均可清晰显示骨纹理、软骨、韧带、半月板等解剖结构,与常规TSE序列比较,SMS-TSE序列在冠状位PDWI-FS序列软骨评分上差异有统计学意义(P0.05),在骨纹理、韧带、半月板、伪影评分上差异均无统计学意义(P0.05);常规TSE序列矢状位T1WI、矢状位PDWI-FS和冠状位PDWI-FS扫描总时间为13.48 min;SMS技术层加速因子为2时,SMS-TSE序列扫描总时间为6.87 min,较常规TSE序列降低49.04%。结论 SMS-TSE序列用于膝关节扫描具有快速、高清成像的优势且图像质量并未明显降低,在膝关节检查中具有重要的临床应用价值。     

胰腺MRI:2D与3D FS-FLASH增强扫描序列的对比研究

目的:通过2D与3D增强扫描序列的对比研究,确定胰腺MRI最佳增强扫描序列。方法:40例胰外疾病患者随机分为2D组和3D组(每组各20例)。常规MRI平扫后行胰腺多时相动态增强扫描。测量平扫T1WI像及增强各期胰腺的信号强度,计算信噪比(SNR)及对比信噪比(CNR),并对图像质量进行评价。结果:平扫T1WI像:3D组胰腺SNR、胰腺-胰周脂肪CNR均明显低于2D组(19.2 vs 22.7,8.7 vs 15.2,P<0.05)。增强后扫描:3D组各期图像的胰腺SNR均高于同期扫描的2D组(37.8 vs 29.4;31.6 vs 28.8;29.6 vs 28.0),尤以胰腺实质期为明显(P<0.05),同时胰腺-胰周脂肪CNR及图像质量亦高于2D组(P<0.05)。结论:3D FLASH序列是胰腺MRI最优增强扫描序列,能更好地显示胰腺的解剖细节和血液动力学特征,有助于胰腺疾病的诊断及可切除性评价。     

MR 3D-PD-SPACE序列在评估正常踝关节韧带肌腱中的应用价值

目的：对比分析3D-SPACE序列及常规2D-TSE在对踝关节韧带及肌腱组织的显示价值。材料与方法21例健康自愿者进行3D-PD-SPACE三维各项同性矢状面扫描和2D-T2WI-FSE二维快速自旋回波各方位扫描,分别测量韧带、肌腱、软骨、关节液、肌肉的信噪比（SNR）以及关节液与软骨、脂肪与韧带、肌肉与肌腱的对比信噪比（CNR）。然后由2名资深MR医生对韧带、肌腱、软骨、关节液的显示效果、细节,图像质量（模糊、假象、容积效应、均匀性）等几方面进行评估,并用5分利克特量表（5-point Likert scale）来评估。结果 SPACE序列各组织SNR明显高于2D序列,两者有统计学意义（P〈0.01）;在关节液与软骨、关节液与韧带、关节液与脂肪、肌肉与肌腱CNR上3D高于2D的序列,两者同样有统计学意义（P〈0.01）。图像质量评估方面SPACE序列在距腓前韧带、跟腓韧带、内侧副韧带、纵向跟舟韧带薄层重建上比2D序列有更多优势,两者之间的差异有统计学意义（P〈0.05）;趾长伸肌腱、胟伸肌腱、腓长肌腱、腓短肌腱及趾长屈肌腱SPACE与2D比较薄层重建同样有统计学意义（P〈0.05）。结论3D-PD-SPASE质子加权各项同性踝关节扫描对踝关节韧带和肌腱的评估有重要价值,由于3D有多平面重建和曲面重建等特点能更好地满足临床的需要。     

MRI增强T1高分辨力各同性容积激发序列与TSE T1W序列检出椎体转移瘤的对比分析

目的 比较增强MRI快速T1高分辨力各向同性容积激发（THRIVE）序列和TSE序列T1W检出椎体转移瘤的价值。方法 对31例经穿刺活检病理证实的椎体转移瘤患者行MR增强检查,增强后先后行常规矢状位TSE T1W序列和矢状位THRIVE序列扫描。比较2个序列显示转移瘤病灶的数目、SNR、CNR和病灶边缘清晰度、运动伪影评分。结果 TSE T1W序列和THRIVE序列扫描时间分别为2 min 55 s和33 s。增强后THRIVE序列显示病灶的数量与TSE T1W序列差异无统计学意义（Z=-0.816,P=0.414）。增强后THRIVE序列的SNR（432.54±271.60）、CNR（233.27±197.65）均低于TSE T1W序列的SNR（674.32±375.79）、CNR（312.38±207.49）,差异均有统计学意义（t=-4.366、-2.660,P<0.001、0.012）。TSE T1W序列显示病灶边缘较THRIVE序列清晰（Z=-4.082,P<0.001）,但运动伪影较THRIVE序列明显（Z=2.291,P=0.022）。结论 增强扫描THRIVE序列扫描时间短,运动伪影少,椎体转移瘤的检出数目与TSE T1WI序列相当,在椎体转移瘤的检查中取代TSE T1W序列具有可行性。     

经距骨颈长轴位MR扫描技术对距腓前韧带的评价

目的:探讨经距骨颈长轴位的MR扫描技术对距腓前韧带的评价。方法:对59例踝关节均行常规横轴位、斜矢状位及斜冠状位扫描,并在常规扫描基础上行与胫距关节平面成25°的斜轴位以及经距骨颈层面的平行于距骨颈长轴的斜轴位TSE T2扫描(改良位)。将改良位、常规横轴位及25°斜轴位影像图形进行对照分析,评价距腓前韧带的显示情况。结果:26例正常组患者距腓前韧带均未见异常,33例有扭伤病史患者其中61%(20/33)表现为损伤,磁共振3种检查方案在正常组及扭伤组中显示距腓前韧带无统计学差异,图像质量3分者改良位占93%(55/59)、25°斜轴位占90%(53/59)、常规位29%(17/59),改良位与常规横轴位图像比较具有统计学差异(P<0.05),改良位图像质量明显高于常规轴位,改良位与25°斜轴位图像比较无明显统计学差异(P>0.05),但改良位图像质量较25°斜轴位好。结论:3种检查方案中改良位显示距腓前韧带图像质量最好,不受体位限制,且可以广泛应用于临床。     

磁共振常规图像诊断腰椎间盘突出的不足:与手术结果对比研究

目的通过与手术结果比较,找出目前腰椎MR横轴位及矢状位图像诊断腰椎间盘突出的缺陷与不足,并提出解决方法。材料与方法回顾100例经手术证实存在腰椎间盘突出并术前有MR平扫资料的病例,观察MR常规序列(包括矢状位T1WI、T2WI及压脂序列,横轴位T2WI),分别以手术结果为标准,计算矢状位与横轴位图像诊断腰椎间盘突出的准确率及对腰椎间盘突出特殊征象的检出率,并分析横轴位及矢状位图像的漏诊原因。结果 MR横轴位图像对腰椎间盘突出总体诊断准确率为93.6%,矢状位为84.8%,前者高于后者(χ~2=5.02,P0.05);横轴位图像对腰椎间盘向上下方突出或脱出和髓核游离的检出率低(36.00%、45.45%),矢状位检出率高(96.00%、100.00%),前者检出率明显低于后者(χ~2=20.05、8.25,P0.05)。横轴位对椎间孔型及椎间孔外侧型椎间盘突出的检出率高(96.30%、88.89%),矢状位上分别为74.07%、38.89%,前者检出率明显高于后者(χ~2=5.28、9.75,P0.05)。横轴位局限于椎间隙层面的扫描范围和矢状位缺乏参照是MR常规图像漏诊椎间盘突出的主要原因。结论 MR常规图像对特殊类型椎间盘突出的漏诊,可以通过密切结合MR矢状位图像,根据需要局部增加横轴位扫描层面或结合三维电子计算机断层扫描(computed tomography,CT)检查来解决。     

探讨双源CT颈动脉造影低管电压扫描的可行性

目的 评价低管电压双源CT扫描应用于颈部血管造影的可行性.方法 选取35例可疑头颈动脉粥样硬化患者行头颈部DSCTA扫描.扫描完成后取得3组数据,其中融合图像重建函数为反投影滤过重建算法(D26),80-kVp数据重建函数分别为D26和迭代重建算法(I26).于颈动脉分叉区及胸廓人口区测定颈动脉血管的噪声、SNR和对比噪声比(CNR),并进行动脉影像质量评级评分.结果 80-kVp(I26)重建图像与融合图像的噪声差异无统计学意义(P＞0.05),80-kVp(D26)重建图像的噪声高于融合图像和80-kVp(I26)重建图像(P均＜0.05).80-kVp(I26)和80-kVp(D26)重建图像的CT值均高于融合图像(P均＜0.05).80-kVp(D26)重建图像与融合图像的SNR和CNR差异无统计学意义(P均＞0.05),80-kVp(I26)重建图像的SNR和CNR高于80-kVp(D26)重建图像和融合图像(P均＜0.05).80-kVp(I26)重建图像、融合图像的图像质量均为优,满足诊断率达100％;80-kVp(D26)重建图像的图像质量及满足诊断率低于80-kVp(I26)重建图像和融合图像(P均＜0.05).结论 DSCT低管电压扫描观察颈动脉病变是可行的,所得图像可满足诊断要求.     

椎管内占位病变的MRI误诊分析

1　对象和方法本组男 4例 ,女 3例 ,年龄 2 3～ 70岁。临床表现为 :腰腿痛、下肢无力、肌张力和腱反射异常以及膀胱、直肠功能障碍。 7例均行手术治疗并经病理证实。使用 Philip′s- Gyroscan T5- 型0 .5 T超导型磁共振仪 ,常规行矢状位及横轴位扫描 ,增强后加冠状位扫描。 T1 加权采用 SE序列 ,T2 加权采用 TSE或 FFE序列。层厚 4 mm,层间距 0 .4 mm,6例行了 GD- DTPA增强扫描。 7例误诊前后的诊断见表 1。表 1　 7例患者手术前后的诊断术前诊断病理诊断　　术前诊断病理诊断胶质瘤　　髓内囊虫病　　　　神经纤维瘤成熟性畸胎瘤…     

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。