声触诊组织量化技术——脾脏剪切波速度无创评估乙型肝炎肝纤维化程度的可行性分析

目的探讨声触诊组织量化(VTQ)技术测量脾脏剪切波速度无创评估乙型肝炎患者肝纤维化程度的可行性。方法应用VTQ技术对246例受试者测量脾脏剪切波速度(SWV),包括60例健康志愿者(归为S0期),53例慢性乙型肝炎患者(S1期12例,S2期19例,S3期20例,S4期2例)及133例临床诊断的乙型肝炎后肝硬化患者(归为S4期),将所得结果按纤维化分期进行分析。结果脾脏SWV与肝纤维化分期相关,相关系数为0.73(P<0.01);SWV在S0、S1、S2、S3期与S4期间差异均有统计学意义(P<0.01),其余各组间SWV差异无统计学意义(P>0.05);诊断S4期的受试者工作特征曲线下面积为0.95,诊断的临界值为2.78 m/s,灵敏性、特异性分别为0.86、0.94。结论基于VTQ技术的脾脏SWV在无创诊断乙型肝炎S4期有较好的应用前景。     

肝脾脏剪切波速评估肝纤维化程度的初步研究

目的探讨肝脏、脾脏剪切波速度(SWV)无创评估肝纤维化程度的临床应用价值。方法研究对象包括100例慢性乙型肝炎患者(S1~S2期61例,S3期39例、)36例肝硬化患者及39例健康对照组,采用VTQ技术测量四组肝脏、脾脏SWV。将上述参数值与病理学分期作对照研究和统计学分析。结果肝脏SWV及脾脏SWV在肝纤维化S1~S2、S3期与S4期、对照组间差异均有统计学意义(P0.05),诊断肝S4期的肝脏SWV的ROC下面积为0.89(95%Cl:0.85~0.93),诊断的截断值为1.81 m/s,灵敏度、特异度分别为0.91%、0.84%。诊断肝S4期的脾脏SWV的ROC下面积为0.91(95%Cl:0.87~0.96),诊断截断值为2.96m/s,灵敏度、特异度分别为0.89%、0.84%。随着肝纤维化程度的加重,肝、脾SWV呈增高的趋势。结论应用VTQ技术无创测量肝脏、脾脏SWV值,二者对临床肝纤维化的诊治具有重要参考价值。     

声触诊组织量化技术——肝脏剪切波速度无创评估乙型肝炎肝纤维化程度的研究

目的 研究声触诊组织量化技术(virtual touch quantification,VTQ)测量肝脏剪切波速度无创评估乙型肝炎患者肝纤维化程度的临床价值.方法 运用VTQ技术对246例受试者测量肝脏剪切波速度(shear wave velocity,SWV),包括60例健康志愿者(归为S0期)、53例慢性乙型肝炎患者(按肝穿病检结果分为S0～S4期)及133例临床诊断的乙型肝炎肝硬化患者(归为S4期);将所得的SWV值按纤维化分级进行分析.结果 肝脏剪切波速度值与肝纤维化分级的相关系数为0.87 (P＜0.001),肝脏剪切波速度值随着肝纤维化的进展而增加.诊断S≥3和S=4期的受试者工作特征曲线下面积(area under the receiver operating characteristic curve,AUROC)分别为0.99、0.98,诊断的临界值分别为1.69 m/s、1.88 m/s,对应的灵敏度分别为0.93、0.96,特异度分别为0.96、0.94.结论 基于VTQ技术的肝脏剪切波速度在无创诊断乙型肝炎肝纤维化程度方面有重要的临床应用价值.     

声触诊组织量化技术无创评价肝纤维化的临床研究

目的 研究声触诊组织量化(VTQ)技术评价肝纤维化程度的临床价值.方法 使用VTQ技术对271例肝穿刺活检或肝脏手术前后1个月内的患者进行肝硬度测量.男207例,女64例,平均年龄(54.00±12.67)岁.使用ACUSON S2000超声诊断仪测量受检者肝右叶VTQ值5~lO次.肝纤维化病理分期根据Scheuer方案分为S0～S4期.以病理诊断为金标准,评价VTQ技术预测肝纤维化程度的价值及其最佳界限值.结果 271例患者中病理诊断为SO~S4期的病例数分别为28例、29例、41例、52例和121例,VTQ平均值分别为(1.26±0.31)m/s、(1.28±0.28)m/s、(1.31±0.31)m/s、(1.54±O.44)m/s和(1.93±0.50)m/s.SO期与S1期、S1期与S2期的VTQ值之间差异无统计学意义.无或轻度肝纤维化(即S0、S1和S2期)、重度肝纤维化(即S3期)和肝硬化(即S4期)两两之间VTQ值差异均有统计学意义.S≥S3期时,BOC曲线下面积为0.821(95%CI:0.771～0.871);S=S4期时,ROC曲线下面积为0.828(95%CI:0.779~0.877).以1.43 m/s为界值,诊断S≥S3期的敏感度为76%,特异度为77%;以1.52 m/s为界值,诊断S=S4期的敏感度为80%,特异度为73%.结论 VTQ技术是一种间接无创评价肝纤维化的新方法,具有广阔的应用前景.     

慢性乙型肝炎患者肝剪切波速度与肝纤维化分期的相关性研究

目的 探讨慢性乙型肝炎患者肝剪切波速度与肝纤维化分期的相关性.方法 使用声触诊组织量化技术(VTQ)对112例慢性乙肝患者肝右叶进行检测,获得肝剪切波速度,并与肝穿刺组织病理学对照,组织学分期参照2000年修订的《病毒性肝炎防治方案》病理诊断标准.结果 S0期15例,S1期17例,S2期15例,S3期23例,S4期42例.S0期与S1期剪切波速度差异无统计学意义,其余各期两两比较差异均有统计学意义.S2期ROC曲线下面积为0.94,以1.27 m/s为界值,诊断S2期的敏感度为80.0％,特异度为89.5％;S3期ROC曲线下面积为0.87,以1.43 m/s为界值,诊断S3期的敏感度为71.8％,特异度为87.7％;S4期ROC曲线下面积为0.95,以1.79 m/s为界值,诊断S4期的敏感度为83.3％,特异度为89.4％0.肝剪切波速度与肝纤维化分期呈正相关(r=0.92).结论 慢性乙型肝炎患者肝实质的VTQ值与病理显示的肝纤维化程度呈正相关,肝纤维化程度越重,肝实质的VTQ值越大.     

声触诊组织成像量化技术无创评价慢性肝病肝纤维化程度的初步临床研究

目的 探讨声触诊组织成像量化(VTQ)技术无创评价慢性肝病患者肝纤维化程度的临床价值.方法 应用VTQ技术对115例拟行超声引导下肝穿刺活检慢性肝病患者和80例健康成人行肝检查,并对检查结果进行对比分析.结果 慢性肝病组和健康组之间VTQ值差异有显著统计学意义(P=0.0000);慢性肝病患者不同病理分期间的VTQ值除S0与S1外,其他病理分期间差异均有统汁学意义(P=0.0212或P=0.0000);将S0-S2合并为轻度肝纤维化,S3-S4合并为中一重度肝纤维化,用ROC曲线分析阈值,当VTQ值≥1.4 m/s时,诊断中-重度肝纤维化的敏感度和特异度分别为85.4%和64.7%.结论 VTQ检查作为无创、量化的检查手段,可用来评价慢性肝病患者的肝纤维化程度.     

声触诊组织量化技术无创评价慢性肝病的初步研究

目的探讨声触诊组织量化技术(VTQ)无创评价肝纤维化程度的临床应用价值。方法对37例肝纤维化(S1)患者、42例肝纤维化(S2)患者、39例肝纤维化(S3)患者、36例肝硬化(S4)患者及70例健康对照组,采用VTQ技术定量测量肝实质剪切波速度(SWV)。以病理结果为金标准,构建受试者工作曲线(ROC曲线),均数间多重比较采用(LSD-t法)。结果 S1~S4期平均肝脏剪切波速分别为1.22m/s、1.37m/s、1.69m/s、2.36m/s,对照组平均剪切波速为1.12m/s,各组肝脏SWV存在显著性差异(P0.05)。S1~S4期ROC曲线下面积分别为0.716、0.785、0.856、0.969。以1.26m/s为界值,诊断≥S1期的灵敏度为68%、特异度为79%;以1.35m/s为界值,诊断≥S2期的灵敏度为79%、特异度为82%;以1.58m/s为界值,诊断S3期的灵敏度为85%、特异度为80%,以1.79m/s为界值,诊断S4期的灵敏度为90%、特异度为91%。结论 VTQ可无创测量肝实质剪切波速度,客观反映肝组织的弹性模量,有望为定量评估肝纤维化分期提供一项客观准确的新方法。     

肝动静脉渡越时间及剪切波速评估肝纤维化程度的对比研究

目的探讨超声造影测量肝动静脉渡越时间(HAVTT)及声脉冲辐射力技术测量剪切波速(SWV)在评估慢性乙型肝炎患者肝纤维化程度中的应用价值。方法 83例S0~S4期慢性乙型肝炎肝病患者,对其肝脏行超声造影及弹性超声检查。超声造影采用目测法测量并计算HAVTT1和HAVTT2;利用声脉冲辐射力技术测量SWV。结果运用ROC曲线得到≥S1期、≥S2期、≥S3期和S4期的SWV参考阈值分别为1.41 m/s、1.81 m/s、2.14 m/s、2.40 m/s,HAVTT1参考阈值分别为11.6 s、10.5 s、9.5 s、7.4 s,HAVTT2参考阈值分别为14.1 s、12.4 s、11.6 s、9.4 s。SWV、HAVTT1、HAVTT2对肝纤维化分期诊断正确率分别为89.2%、72.3%、77.1%,前者高于后两者(P0.05)。结论超声造影测量HAVTT可反映肝脏微循环的变化,可用于对S2期和S3期肝纤维化的鉴别诊断。超声弹性成像测量SWV能够反映肝纤维化分期的弹性硬度差异,较超声造影使用更方便、更无创,可作为评判肝纤维化程度及治疗疗效的一种新方法。     

声辐射力脉冲成像和天冬氨酸转氨酶与血小板比值诊断酒精性肝病肝纤维化程度的价值

目的探讨声辐射力脉冲成像(ARFI)技术和天冬氨酸转氨酶与血小板比值(APRI)诊断酒精性肝病(ALD)肝纤维化程度的临床价值。方法 108例ALD患者应用ARFI技术对肝脏弹性进行检测,获得剪切波速度(SWV)同时计算APRI,所有患者均于检测后1周内行肝穿刺活检,以病理结果为金标准,比较SWV和APRI对ALD肝纤维化的诊断价值。结果 ALD肝纤维化S0~S4期的SWV分别为(1.11±0.08)m/s、(1.24±0.17)m/s、(1.50±0.35)m/s、(2.01±0.70)m/s及(2.13±0.68)m/s,APRI分别为0.18±0.08、0.19±0.13、0.37±0.24、0.75±0.91及0.75±0.63。SWV和APRI均与肝纤维化分期存在正相关,相关系数分别为0.60和0.55(P=0.000)。SWV诊断ALD肝纤维化ROC曲线下面积分别为≥S1期0.88,≥S2期0.81,≥S3期0.83,S4期0.82;APRI对应的ROC曲线下面积分别为0.65、0.80、0.78及0.78。结论对于定量诊断ALD肝纤维化程度,ARFI技术较APRI有更高的诊断价值,具有良好的临床应用前景。     

声触诊组织量化技术无创评估乙型肝炎肝硬化食管静脉曲张程度

目的 探讨声触诊组织量化(virtual touch tissue quantification,VTQ)技术无创评估乙肝肝硬化食管静脉曲张(esophageal varices,EV)程度的可行性.方法 应用VTQ技术对135例乙型肝炎后肝硬化患者分别测量肝、脾剪切波速度值(shear wave velocity,SWV);同时行胃镜检查,分为无食管静脉曲张组与食管静脉曲张组(按食管静脉曲张程度分为轻、中、重三级);检查肝生化指标;将所得的肝SWV及脾SWV值进行对比分析.结果 乙肝肝硬化患者的肝SWV均值为(2.48±0.50) m/s;肝SWV值与食管静脉曲张分级间无相关性(P=0.167).乙肝肝硬化患者的脾SWV均值为(3.25±0.44)m/s;脾SWV值与食管静脉曲张分级高度相关,相关系数为0.66(P＜0.001);诊断存在食管静脉曲张的临界值为3.16m/s,灵敏度、特异度分别为0.83,0.80,ROC曲线下面积为0.83;诊断重度食管静脉曲张的临界值为3.39m/s,灵敏度、特异度分别为0.83,0.77,ROC曲线下面积为0.84.结论 VTQ技术测定的脾SWV值可无创评估乙肝肝硬化患者食管静脉曲张程度,但未发现肝SWV值可用于评估食管静脉曲张程度.     

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.     

Dissociable correlates of two classes of retrieval processing in prefrontal cortex

Although substantial evidence suggests that the prefrontal cortex (PFC) implements processes that are critical for accurate episodic memory judgments, the specific roles of different PFC subregions remain unclear. Here, we used event-related functional magnetic resonance imaging to distinguish between prefrontal activity related to operations that (1) influence processing of retrieval cues based on current task demands, or (2) are involved in monitoring the outputs of retrieval. Fourteen participants studied auditory words spoken by a male or female speaker and completed memory tests in which the stimuli were unstudied foil words and studied words spoken by either the same speaker at study, or the alternate speaker. On "general" test trials, participants were to determine whether each word was studied, regardless of the voice of the speaker, whereas on "specific" test trials, participants were to additionally distinguish between studied words that were spoken in the same voice or a different voice at study. Thus, on specific test trials, participants were explicitly required to attend to voice information in order to evaluate each test item. Anterior (right BA 10), dorsolateral prefrontal (right BA 46), and inferior frontal (bilateral BA 47/12) regions were more active during specific than during general trials. Activation in anterior and dorsolateral PFC was enhanced during specific test trials even in response to unstudied items, suggesting that activation in these regions was related to the differential processing of retrieval cues in the two tasks. In contrast, differences between specific and general test trials in inferior frontal regions (bilateral BA 47/12) were seen only for studied items, suggesting a role for these regions in post-retrieval monitoring processes. Results from this study are consistent with the idea that different PFC subregions implement distinct, but complementary processes that collectively support accurate episodic memory judgments.     

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.