单次屏气电影法MRI评价左心室功能的初步研究

目的评价单次屏气电影法测量心功能的价值.方法应用单次屏气电影法与多次屏气电影法随机检查16例心脏病患者,比较两种方法测量所得心功能指标,包括左心室舒张末期容量(EDV),收缩末期容量(ESV),搏出量(SV),射血分数(EF)及心肌质量(MM).结果各个均值比较差异两组间无显著性,并呈明显直线相关关系.结论单次屏气电影法明显缩短心功能测量时间,是一种有价值的方法.     

64层螺旋CT与磁共振成像评价左心功能的比较研究

目的以磁共振为对照,应用64层螺旋CT(MSCT)定量评价左心功能,探讨MSCT成像技术和屏气法MRI电影技术心功能评价指标的相关性及MSCT在冠心病左心功能评价中的应用价值。方法临床拟诊冠心病的患者20例,均自愿参加。全部病例均行心脏MSCT和MRI检查。结果MSCT和MRI两种方法的心功能指标无显著性差异,两种方法的心功能指标舒张末期容积(EDV)、收缩末期容积(ESV)、每搏输出量(SV)、左室射血分数(EF)、心肌质量(MM)相关性高,r值=0.72~0.92。MSCT所测EDV、ESV、SV和MM值较MRI偏大,MSCT所测EF值较MRI偏小。结论本研究显示64层螺旋CT在左心功能定量评价方面准确、可靠,与3.0T磁共振两种方法各指标之间相关性高。一次MSCT冠状动脉成像检查,可以同时评估冠状动脉狭窄情况和左心室功能。     

MRI评价心功能

心血管疾病的诊断需要对心脏形态和功能作出准确评价，MRI可满足上述要求。传统电影法和屏气电影法MRI能够对左右室的整体和局部功能进行准确和可重复性测量，MRI流速编码电影（velocity－encodedcine，VEC）技术能测量心脏大血管内的血流速度，快速梯度回波序列和团注对比剂能够观察造影剂的首次通过情况，显示心肌的血流灌注。最近，应用屏气VEC技术可显示冠状动脉的主干和大分支，它提供了一种确定冠状动脉通畅性的无创方法，使早期发现无症状冠状动脉疾病患者成为可能。本文全面探讨MRI心功能评价能力，并介绍几种具有潜在应用…     

3D自由呼吸与屏气扫描磁共振心肌延迟成像技术对比

目的比较对心肌梗死患者采用3D自由呼吸(3DFB)采集与单次屏气(BH)采集反转恢复梯度回波序列心肌延迟成像的图像质量。方法对20例心肌梗死患者分别行呼吸导航回波触发、3DFH反转恢复梯度回波扫描和3DBH反转恢复梯度回波扫描,以"优=4、良=3、一般=2、差=1"四个级别评判心肌图像质量,计算两组左室心肌面积均值、梗死心肌面积均值、延迟强化心肌信噪比和对比噪声比,测量心肌梗死透壁程度。采用SPSS12.0软件对两组结果进行t检验分析。用相关回归法评价两种采集方法在计算左室活性心肌百分比方面的一致性。结果FB组图像质量评分高于BH组。两组图像信噪比和对比噪声比差异有统计学意义,左室心肌面积均值、梗死心肌面积均值差异无统计学意义,两组透壁厚度分别为(5.13±2.74)mm和(6.81±3.15)mm(P<0.05)。结论呼吸导航回波触发反转恢复梯度回波扫描可有效应用于3D磁共振心肌延迟成像,与单次屏气采集3D反转恢复梯度回波序列相比,可显著提高图像质量和分辨率,对坏死心肌能作出更为精确的量化评价。     

心脏磁共振延迟强化成像定量评价心肌梗死的研究

目的 研究计算机辅助测体积法(CAVM)与视觉评分法(VSM)在心脏磁共振延迟强化成像上评价梗死心肌大小的相关性,并探讨梗死心肌质量与室壁运动异常、左室功能的相关性.方法 采用多次屏气平衡稳态自由进动快速成像(FIESTA)序列,对21例心肌梗死患者行心脏电影MRI及钆喷替酸葡甲胺(Gd-DTPA)增强的延迟强化成像.①用CAVM及VSM分别评价患者的梗死心肌质量及梗死心肌范围程度.用VSM评价时根据延迟强化的透壁程度分为0～4分;0＝无强化,1＝1%～25%强化,2＝26%～50%强化,3=51%～75%,4=76%～100%强化;②评价患者的室壁运动异常及左室功能.结果 两种方法评价梗死心肌高度相关(r=0.825,P＜0.001);梗死心肌质量与室壁运动异常(r=0.740)、射血分数(r=-0.733)、收缩末期容积指数(r=0.702)、收缩末期容积(r=0.698)、舒张末期容积指数(r=0.657)、舒张末期容积(r=0.648)均密切相关(P≤0.001).结论 计算机辅助测体积法及视觉评分法均可准确定量梗死心肌,梗死心肌质量与室壁运动异常、左室功能有高度相关性.     

实时三维超声心动图与MRI对慢性阻塞性肺病患者右室功能评估的对比研究

目的以MRI电影成像法为对照,应用实时三维超声心动图定量评价慢性阻塞性肺病(COPD)患者右室功能,探讨两种技术心功能评价指标的相关性及实时三维超声心动图在COPD患者右心功能评价中的应用价值。方法 18例COPD患者于24 h内行心脏实时三维超声心动图和MRI检查,获取舒张末期容积(EDV)、收缩末期容积(ESV)、每搏输出量(SV)及射血分数(EF),与MRI多次屏气电影法测得的右室功能指标进行相关分析,评价两种检查方法的一致性。结果实时三维超声心动图和MRI多次屏气电影法测得的EDV分别为(113.82±19.69)ml和(122.22±25.46)ml(r=0.924),ESV为(63.44±12.97)ml和(60.54±11.25)ml(r=0.896),SV为(46.48±11.13)ml和(48.47±14.15)ml(r=0.754),EF为(43.26±5.30)%和(45.71±6.90)%(r=0.616),两种检查方法比较差异无统计学意义,相关性较高。结论实时三维超声心动图在COPD患者右心功能定量评价方面准确可靠,与MRI评价COPD患者右心功能各指标之间相关性高。     

健康猪左室功能MR测定及多巴酚丁胺负荷实验研究

目的:应用MR电影成像评价健康猪左室功能和多巴酚丁胺负荷实验。方法:对9只健康小型猪行MR电影成像测量左室容量和心肌质量,并比较静息状态和负荷状态下心肌增厚率的变化。结果:在垂直于室间隔的左室短轴MR电影图像上测量左室舒张末期容量(LVEDV)/体重(BW)为(2.4±0.3)ml/kg,左室收缩末期容量(LVESV)/BW为(1.1±0.1)ml/kg,左室心肌质量(LVM)/BW为(3.03±0.21)ml/kg,射血分数(EF)为(55±3)%。小剂量多巴酚丁胺[5μg/(kg·min),10(μg/kg·min)]能增加正常心肌收缩力,使左室收缩期心壁厚度和左室心肌增厚率较静息状态有显著增加。结论:心脏电影MR图像分辨率高,可测定心功能多项指标,小剂量多巴酚丁胺静滴安全,并能够增加心肌收缩力。     

实时三维超声心动图与磁共振成像评价右心功能的对照研究

目的:以磁共振电影成像法为对照,应用实时三维超声心动图定量评价右心室功能,探讨两项技术心功能评价指标的相关性及实时三维超声心动图在右心功能评价中的应用价值.方法:30例健康成年志愿者(男16例、女14例,年龄(49±3.2)岁),全部志愿者均于24 h内行心脏实时三维超声心动图和MRI检查.行实时三维超声心动图全容积显像方式采集图像数据,并导入TomTec工作站,应用4D RV-function软件行图像后处理,构建右室三维模型并进行心功能测量.最终获取舒张末期容积(EDV)、收缩末期容积(ESV)、每搏输出量(SV)及射血分数(EF)等心功能参数.与MR多次屏气电影法测得右心室功能指标进行Pearson相关分析,并采用Bland-Altman法评价两种检查方法结果的一致性.结果:实时三维超声心动图测得的心功能指标平均EDV (143.5±23.2) mL,平均ESV (68.4±19.2) mL,SV (78.1±11.7) mL,EF (51.2±5.6)％,与MR多次屏气电影法测得的心功能指标EDV (147.5±26.8) mL(r=0.947),ESV (63.2±15.9) mL(r=0.909),SV (78.8±15.0) mL(r=0.788),EF (55.2±7.7)％(r=-0.627)均无显著性差异,显示出较高相关性.结论:本研究显示实时三维超声心动图与1.5T磁共振成像评价右心功能各指标之间相关性高,在右心功能定量评价方面准确、可靠.     

电影磁共振成像评价急性心肌梗塞后左室重构的实验研究

目的探讨电影磁共振成像在评价急性心肌梗塞后左室重构方面的价值。方法对２５只犬分别于冠状动脉左前降支结扎术前和术后３小时进行电影磁共振成像检查,并测量舒张末期和收缩末期梗塞和非梗塞心肌节段的室壁厚度、长度及左室容积。结果电影磁共振成像能动态观察各心肌节段的室壁运动情况,能清晰准确地显示梗塞区室壁伸展、左室扩大和左室收缩功能受损情况。结论电影磁共振成像能为临床及早发现左室重构提供更加准确可靠的依据     

2D 与3D 延迟增强扫描对心肌梗死诊断的对比研究

目的对比一次屏气3D反转恢复梯度回波序列与多次屏气2D反转恢复梯度回波对于评价心肌梗死及其范围作用。方法对19例（34灶）心肌梗死的患者的2D和3D反转恢复的梯度回波序列扫描结果进行分析。分别评价心肌有无延迟增强及其延迟增强的类型，并且测量心肌梗死的范围（延迟强化累及的层数）及透壁程度。结果2D和3D反转恢复的梯度回波序列对于心肌梗死的诊断和分类以及显示心肌梗死的范围无统计学差异，但2D和3D反转恢复的梯度回波序列对于显示心肌梗死的透壁厚度有统计学差异，3D序列过度估计了心肌梗死的透壁程度。结论3D的反转恢复的梯度回波序列可以快速地评价有无心肌的梗死，与标准的2D反转恢复梯度回波序列有高度地一致性。     

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.     

手转胎头术失败的原因与分娩结局临床分析

目的 探讨手转胎头术失败的原因与分娩结局.方法 选择2008年1月至2010年12月于我院住院分娩的持续性枕横位、枕后位产妇198例,根据行手转胎头术后结果分为成功组126例、失败组72例.比较两组分娩结局,对比分析失败原因.结果 失败组胎儿体质量≥3500 g的发生率[76.4％(55/72)]明显高于成功组[31.7％(40/126)],差异有统计学意义(x2=30.177,P=0.001)、失败组宫缩乏力发生率[58.3％(42/72)]高于成功组[38.1％ (48/126)],差异有统计学意义(x2=7.569,P=0.006)、失败组骨盆临界或轻度狭窄发生率[38.9％ (28/72)]高于成功组[23.8％(30/126)],差异有统计学意义(x2 =5.030,P=0.002)、失败组手转胎头时机不当(宫口开大＜6 cm、胎头位于坐骨棘上及宫口开大8～10 cm、胎头位于坐骨棘下≥2 cm)发生率[61.1％(44/72)]高于成功组[38.9％(49/126)],差异有统计学意义(x2=9.084,P=0.003).失败组母儿并发症(产后出血、产褥病率、胎儿窘迫、新生儿窒息)发生率高于成功组(x2 =9.586,P=0.002、x2=9.334,P=0.002、x2=5.910,P=0.015、x2=5.240,P=0.022)、失败组剖宫产发生率[72.2％(52/72)]明显高于成功组[34.1 ％(43/126),x2=26.641,P=0.001)].结论 手转胎头术能使难产变顺产,降低剖宫产率,减少母儿并发症,但须积极预防、处理导致手转胎头术失败的原因,对矫正失败后继续矫正及试产应慎重.     

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.     

Wie zuverlässig sind Angaben zu nichtentzündlichen ausgedehnten Schmerzen?

ZusammenfassungFragestellung Es wurde geprüft, wie sich der Differenziertheitsgrad zweier Schmerzmessmethoden auf Angaben zur Ausgedehntheit klinischer Schmerzen auswirkt. Zugleich wurde der Referenzzeitraum variiert, über den die Patienten berichten sollten.Methode Erfasst wurde der Einfluss zu Lasten der Befragungsdifferenziertheit durch den Vergleich zweier Körperschema-Bildvorlagen. Drei Referenzzeiträume (Schmerz aktuell, letzte Woche, letztes halbes Jahr) wurden vorgegeben.Ergebnisse Patienten mit ausgedehnten Schmerzen gaben bei differenzierter Befragung um so mehr Schmerzen an, je weiter die Schmerzen zurück lagen und je größer der Berichtszeitraum war. Patienten mit gelenknahen Schmerzen gaben bei hoch differenzierter Befragung weniger ausgedehnte Schmerzen in der Vergangenheit an als bei globaler Einschätzung. Patienten mit Rückenschmerzen berichteten bei differenzierter Befragung zum aktuellen Schmerz über weniger ausgedehnte Schmerzen als bei globaler Befragung.Schlussfolgerung Die Angaben zur Schmerzausdehnung variieren vor allem bei Patienten mit ausgedehnten Schmerzen in Abhängigkeit von der Differenziertheit der Befragung. In diesen Fällen ist die Wahrscheinlichkeit erhöht, dass sich die Beschwerdesymptomatik zumindest teilweise erst in der Reaktion auf die situativen Befragungsbedingungen konstituiert und daher nicht auf andere Befragungsbedingungen generalisiert werden kann.