高血压患者左室心肌背向散射积分变化及其与舒张功能关系的临床研究

目的采用心肌背向散射积分(IBS)技术评价高血压病患者心肌病变的严重程度,并探讨其与左室舒张功能的关系.方法高血压病组117例和对照组30例,二维超声心动图获取左室射血分数 (EF);脉冲多普勒(PW)获取二尖瓣口血流速率E/A、E峰下降时间(DT)与等容舒张时间(IVRT) ;脉冲多普勒组织成像技术(PW-DTI)获得二尖瓣环舒张早期峰值速率Em;运用IBS测量和分析:室间隔(IVS)和左室后壁(LVPW)的心肌背向散射积分(IBS)、校正IBS (IBS%)、IBS周期变化幅度(CVIB)、跨壁梯度(TGIB) 及左室平均CVIB (averaged CVIB,ACVIB).结果根据E/A 、Em、IVRT将原发性高血压患者分为4组:舒张功能正常组(组1)、松弛异常组(组2)、充盈假性正常化组(组3)、限制性左室充盈障碍组(组4 ).(1)组1与对照组的IBS%、CVIB、TGIB之间无显著差异性,而舒张功能异常组(组2 、组3、组4)与对照组相比,IBS%增高、CVIB减低、TGIB增高;(2)相关回归分析表明舒张功能异常组ACVIB的变化与DT、IVRT相关,ACVIB的减低与Em减低密切相关.结论超声背向散射积分技术可反映高血压患者心肌病变的严重程度, 评价其舒张功能,有一定的临床应用价值.     

应用背向散射积分技术评价糖尿病心肌病变的临床研究

目的　应用背向散射积分技术研究糖尿病患者的心肌超声组织特征 ,旨在探讨背向散射积分 (integrated backscatter,IBS)参数测定在评价糖尿病患者心肌病变方面的临床应用价值。方法　采用 HP Sonos5 5 0 0型超声诊断仪 ,该机配置声学密度定量 -背向散射积分 (AD- IBS)联机采样分析软件 ,检测了 17例无微血管并发症的 2型糖尿病患者 (I组 )和 17例有微血管并发症的糖尿病患者 (II组 )以及 16例正常人 (对照组 )心肌的心动周期时间平均背向散射积分 (IBS)、背向散射积分标化值 (IBS% )、背向散射积分周期变异幅度 (CVIB)、背向散射积分跨壁梯度 (TGIB)等超声背向散射积分参数 ,采样部位为胸骨旁左室长轴切面室间隔及左室后壁心肌的中间段。同时测定糖尿病患者的糖化血红蛋白 (Hb A1c)水平。运用 t检验进行 3组受检者心肌超声背向散射积分参数的显著性检验 ,对糖尿病患者的 TGIB与Hb A1c进行相关性分析 ,P<0 .0 5定义为有统计学意义。结果　 (1)糖尿病 I组、II组室间隔及左室后壁心肌的 IBS%均明显高于对照组 ;(2 )糖尿病 I组、II组室间隔及左室后壁心肌的 CVIB均明显低于对照组 ;(3)糖尿病 I组、II组室间隔及左室后壁心肌的 TGIB均显著高于对照组 ;(4 )糖尿病 II组室间隔及左室后壁心肌的 IBS%均明显高于糖     

高血压患者不同左室构型心肌背向散射和彩色室壁运动技术的临床研究

目的：探讨背向散射和彩色室壁运动(CK)参数评估高血压患不同左室构型心肌的病变程度和局部室壁运动的临床价值。方法：对70例原发性高血压病患和31例正常对照进行心肌背向散射和局部彩色室壁运动状态检测。结果：高血压各组室间隔IB％均不同程度地增高．以向心性肥厚组和离心性肥厚组为；在向心性肥厚组和离心性肥厚组室间隔CVIB减低，左室后壁IB％增高；左室后壁的CVIB在离心性肥厚组显减低；高血压各组均未出现明显的背向散射跨壁梯度的改变。室间隔和左室后壁中段的SEM在离心性肥厚组显减低．其余各组间虽无明显统计学差异，但在向心性肥厚组呈现增加的趋势。在离心性肥厚组，收缩末期CK图像显示色带变薄或消失，色带层次不完整。结论：心肌超声背向散射参数和彩色室壁运动技术可用于判断高血压不同左室构型心肌病变程度和局部室壁运动状态。     

高血压左室向心性肥厚时超声背向散射变化的研究

目的通过对高血压左室向心性肥厚时左室心肌超声背向散射的研究,探讨超声背向散射技术能否用来评价高血压左室心肌重构的程度。方法正常对照组(CON)31例,利用二维心脏超声测量高血压患者左室几何形态参数,依据相对室壁厚度(RWT)和心肌重量指数(LVMI)将筛选出高血压左室向心性肥厚(CON)28例;并用超声背向散射技术测量左室心肌不同切面的声学密度的变化。结果左室向心性肥厚组IVSL、PWL(胸骨旁长轴切面间隔后壁)及IVSA(四腔切面室间隔)、LWA(四腔切面侧壁)的IB(标化的平均声学密度)高于正常对照组(P<0.05);左室向心性肥厚组IVSL的IB与LVMI呈正相关(r=0.43,P<0.05);两组间背向散射积分周期变异幅度(CVIB)均无显著差异;两组跨壁背向散射积分(TGIB)及跨壁心动周期变化的背向散射积分(TGCVIB)较正常无显著差异。结论心肌声学密度变化较敏感的反映高血压左室心肌重构的程度。     

高血压病左心室重构的超声评价

目的探讨高血压病左心室向心性重构与向心性肥厚的超声学特征.方法超声检测116例高血压病患者的左心结构、左心室舒张与收缩功能及背向散射积分,分析向心性重构型与向心性肥厚型上述超声检测参数的主要异同.结果高血压病左心室向心性重构型和向心性肥厚型患者左心室舒张末期室间隔厚度(IVSTd)、舒张末期左心室后壁厚度(LVPWTd)、舒张晚期心房收缩时肺静脉反流持续时间(ARD)较正常构型高(P＜0.05),左心室射血分数(EF)斜率、E/A比值、左心室中层缩短率(mFs)较正常构型低(P＜0.05);舒张末期左心室内径(LVEDd)、舒张末期左心房容积(LAEVd)、左心室重量指数(LVMI)、左心室等容舒张期时间(IVRT)、收缩末期室壁应力(ESWS)、Tei指数及室间隔(IVS)、左心室后壁(LVPW)的背向散射积分(IBS)周期性变化幅度的跨壁梯度(TGCVIB)等,在向心性肥厚型均高于向心性重构型(P＜0.05);而E峰、IVS的IBS周期性变化幅度(CVIB)等指标,则为向心性重构型高于向心性肥厚型(P＜0.05).结论上述超声参数是反映高血压向心性重构与向心性肥厚结构和功能变化特征的敏感指标.     

高血压患者二次组织谐波成像后左室心肌背向散射积分变化

目的二次组织谐波成像(STHI)与基波成像(FI)后应用背向散射积分(IBS)评价高血压心肌病变.方法对高血压Ⅰ期患者24例(高血压1组)、高血压Ⅱ～Ⅲ期患者36例(高血压2组)和正常对照组22例,测量和分析STHI与FI后室间隔及左室后壁心肌IBS、IBS%、周期变化(CVIB)及跨壁梯度(TGIB)变化.结果高血压1组与正常对照组比较,各指标间差异均无显著性意义.高血压2组STHI和FI时,室间隔与左室后壁的IBS%值增高;室间隔与左室后壁的CVIB值减低和左室后壁TGIB值增高.三组STHI时,室间隔与左室后壁的IBS% 均高于FI.结论应用二次组织谐波成像后背向散射积分技术可以更敏感地定量评价高血压心肌病变的严重程度.     

声学密度定量技术评价梗死心肌的组织特征

目的　探讨声学密度定量 (AD)技术评价梗死心肌组织特征的临床价值。方法　通过检测心肌背向散射积分参数并与放射性核素心肌显像及常规超声心动图进行比较 ,检测 42例各期前间壁心肌梗死患者的心肌及 2 0例对照者的正常心肌背向散射积分标化值 (IBS % )、背向散射积分周期变异幅度 (CVIB)、背向散射积分周期变异率 (CVIB % )、背向散射积分周期变异延迟率 (DTCV % ) ,同时测量舒张末期室间隔 /左室后壁厚度比值 (IVS/PW )、收缩期室壁增厚率 (ΔT % )及99m锝 甲氧基异丁基异腈 (MIBI)评分指数。结果　梗死心肌IBS %、DTCV %较正常心肌显著增高 (P <0 .0 0 1) ,而CVIB及CVIB %显著减低 (P <0 .0 0 1) ,CVIB及CVIB %与ΔT %及IVS/PW之间呈高度相关 (CVIB :r分别为 0 .75和 0 .6 3 ,P <0 .0 0 1;CVIB % :r分别为 0 .76和 0 .6 8,P <0 .0 0 1)。IBS %、CVIB、CVIB %与99m锝 MIBI评分指数之间呈较高的相关性 (r分别为 0 .5 8,-0 .6 8和 -0 .70 ,P<0 .0 1)。结论　声学密度定量技术能够敏感反映梗死心肌的组织学特征 ,为判定心肌活性或心肌纤维化程度提供新的技术手段     

心肌背向散射积分参数评价蒽环类抗肿瘤药心脏毒性的临床研究

目的 :探讨背向散射积分参数分析技术在评价蒽环类抗肿瘤药 (ATC)心脏毒性方面的应用价值。方法 :应用 HP Sonos550 0型超声诊断仪及其配置的背向散射联机分析软件测定 83例接受 ATC化疗的肿瘤患者及 50例正常对照组心肌背向散射积分参数 :心肌背向散射积分均值 (IBS) ;背向散射积分的心动周期变化幅度 (CVIB) ;心肌校正的背向散射积分均值 (IBS% )和背向散射积分周期变异率 (CVIB% )。结果 :ATC化疗组与对照组心肌 IBS均呈周期性变化 ,但 ATC化疗组变化幅度明显减低 ;ATC化疗组心肌 IBS%较对照组明显增高 (P<0 .0 5) ,CVIB和 CVIB%则较对照组明显减低 (P<0 .0 5,P<0 .0 1) ;ATC化疗组中 3 0例 (3 6.1% )患者出现左心室舒张功能指标异常 ,其中 E/A明显低于对照组。但左心室收缩功能参数和室间隔 (IVS)及左室后壁 (L VPW)的室壁增厚率 (Δ T% )在 ATC化疗组和对照组之间无显著性差异 ;IBS参数与 ATC累积剂量、距首次化疗时间、心功能参数及相应节段的室壁增厚率均无显著相关性。结论 :ATC化疗组患者心肌组织背向散射积分参数与对照组显著不同 ,背向散射积分参数测定可作为评价 ATC早期心脏毒性的手段之一。     

糖尿病患者心肌背向散射积分参数变化及其与心脏功能的关系

目的　观察心肌背向散射积分 (integrated backscatter,IBS)参数在糖尿病患者中的变化 ,并探讨背向散射积分参数与心脏功能的关系。方法　采用 HP Sonos 5 5 0 0型超声波诊断仪 ,检测了 34例 型糖尿病患者及 1 6例正常人的心肌背向散射积分参数 (IBS、 IBS%、 CVIB、 CVIB%及 TGIB) ,并同时测量了心脏收缩功能指标 (EF)和心脏舒张功能指标 (E、 A、 E/ A、 EDT、 IVRT)。采样部位为胸骨旁左室长轴切面室间隔及左室后壁中间段。结果　发现糖尿病患者心肌背向散射积分参数与对照组间有显著性差异 ,IBS%及 TGIB增大 ,P<0 .0 0 1 ,而 CVIB及 CVIB%减小 ,P<0 .0 0 1 ,CVIB及 CVIB%与 EF间相关良好 ,IBS%、 CVIB、 CVIB%、 TGIB与舒张功能指标间密切相关。结论　糖尿病患者心肌组织特征与正常人明显不同 ,心肌背向散射积分参数与心脏功能指标相关良好 ,通过分析心肌背向散射积分参数不仅可以评价糖尿病患者的心肌病变 ,而且可以协助评价心脏功能     

超声背向散射积分技术评价糖尿患者微血管病变对心肌的影响

目的 探索超声背向散射积分技术在评价糖尿病人微血管病变对心肌的影响方面的价值。方法 应用HPSONOS5500型超声诊断仪观测15例有微血管并发症和20例无微血管并发症的2型糖尿病（DM）人及25例正常人的室间隔（IVS），左室后壁（LVPW）心肌背向散射参数。包括，标化背向散射积分值（IB%），背向散射积分值变化幅度（CVIB），背向散射积分值变化幅度的跨壁梯度（TG-CVIB）。结果 两组2型DM病人的IVS和LVPW的IB%均高于正常对照组。CVIB则低于正常对照组；两组DM病人之间的IB%和CVIB无显著差异；有微血管并发症组的IVS和LVPW的TG-CVIB低于无并发症组与正常组，无微血管并发症组与正常组的TG-CVIB无显著差异。结论 超声背向散射技术可反映2型糖尿病人微血管病变对心肌的损害，有一定的临床应用价值。     

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.