极速脉搏波技术定量评价健康成人颈动脉弹性的研究

目的探讨极速脉搏波技术评价健康成人颈动脉弹性的参数及影响因素。方法健康体检志愿者128例,按年龄分为5组:20~29岁组(n=34),30~39岁组(n=22),40~49岁组(n=16),50~59岁组(n=36),≥60岁组(n=20)。灰阶超声测量颈动脉内-中膜厚度(IMT)。极速脉搏波技术测量颈动脉弹性参数,包括收缩期开始时的脉搏波传导速度(PWVBS)和收缩期结束时的脉搏波传导速度(PWVES)。比较IMT、PWVBS及PWVES在两侧颈总动脉、不同性别组及不同年龄组之间的差异,分析PWVBS、PWVES与IMT的相关性。其中30例受检者分别经两名医师检测,比较不同操作者对同一组受检者颈动脉弹性参数的差异。结果 IMT、PWVBS、PWVES在两侧颈动脉及不同性别组间差异无统计学意义。随着年龄的增加,颈动脉PWVBS和PWVES逐渐升高。PWVBS和PWVES与IMT呈正相关(r=0.236、0.462)。不同操作者检测同一组受检者的颈动脉弹性参数差异无统计学意义(P=0.899)。结论极速脉搏波技术能快速、直接测量局部血管弹性参数PWVBS和PWVES,为临床早期准确评价动脉弹性提供了新的手段。     

浸润式超声与接触式超声测量头静脉内径的可重复性研究

目的评价浸润式、接触式超声在测量头静脉内径中的可重复性。方法由2名从事超声诊断工作10年以上的医师,对重庆医科大学附属大学城医院收治的38例预行桡动脉-头静脉内瘘成形术前的患者,在左前臂同一位置处、不同时间点,分别使用浸润式、接触式超声2种方法进行头静脉内径测量。使用组内相关系数(interclass correlation coefficient,ICC)评价测量的组内和组间一致性。并进行Bland-Altman绘图分析,以再次评价重复性。结果浸润式超声法测量值组内和组间一致性非常好,ICC分别为0.968(95%CI:0.939~0.983,P<0.001)和0.960(95%CI:0.924~0.979,P<0.001)。接触式超声法测量值组内和组间一致性好,ICC分别为0.718(95%CI:0.521~0.843,P<0.001)和0.692(95%CI:0.482~0.827,P<0.001)。浸润法超声测量头静脉内径的组内与组间Bland-Altman散点图中,落在95%一致性界限(limits of agreement,LOA)内的点均为97%,接触法超声组内与组间Bland-Altman散点图中,落在95%LOA内的点均为94%。浸润式超声获得头静脉二维图像中,近场组织结构更清晰、头静脉前壁与腔内结构更清楚。同时,浸润式超声显示检查范围更广,更容易同时显示头静脉与桡动脉。结论浸润式超声测量头静脉内径的重复性优于接触式超声,浸润式超声获得的二维图像中,近场组织结构及扫描检查范围均优于接触式超声,浸润式超声可作为桡动脉-头静脉内瘘术前测量头静脉内径的优选方法。     

采用统一操作方法E-Cervix技术评估孕中晚期宫颈弹性

目的评价以统一操作方法E-Cervix技术测量孕中晚期孕妇宫颈弹性参数的一致性。方法将160名孕中晚期孕妇分为宫颈内口闭合组(n=80)及开放组(n=80),于其中各随机选取40名作为统一操作亚组,其余40名为非统一操作亚组。由2名超声医师对各亚组孕妇行E-Cervix检查,测量宫颈弹性参数,包括弹性对比指数(ECI)、硬度比值(HR)、宫颈内口应变(IOS)、宫颈外口应变(EOS)、宫颈内外口应变比(IOS/EOS)及宫颈长度(CL)。采用组内相关系数(ICC)评价观察者内测量结果的一致性;如操作后每名医师测得各亚组内全部参数的ICC均≥0.6,则以Bland-Altman法评价观察者间测量参数的一致性。结果非统一操作时,每名医师测得每组部分参数ICC<0.6(P均<0.05);采用统一方法操作,每名医师测得参数的ICC均>0.8(P均<0.05)。统一操作后,Bland-Altman分析显示观察者间测量参数的一致性良好,各参数差值中95%~100%位于95%一致性界限内,差值的均值、回归方程的截距与斜率均无统计学意义(P均>0.05)。结论以统一方法行孕中晚期E-Cervix检查,所测宫颈弹性参数结果的一致性较高。     

三维超声测量斑块体积的临床应用价值

目的评价三维超声技术测量颈动脉粥样硬化斑块体积的实用性及可重复性。方法 2名医师独立运用二维及三维超声技术检查52例颈动脉粥样硬化患者,观察斑块的形态、测量斑块的面积及联合运用VOCAL技术测量斑块体积,并用Bland-Altman分析、配对t检验分析2名医师测量的结果。结果二维及三维超声均可以显示斑块的位置、形态及大小,二维超声只能显示斑块某一切面,三维超声可显示斑块的立体形态;同时Bland-Altman分析得出,2名医师测量斑块面积及体积的95%一致性界限分别是:(-0.09,0.10)cm2、(-0.11,0.09)cm3,采用配对t检验分析2名医师测量差值无统计学意义(P>0.05),以上统计分析得出2名医师测量斑块面积及体积的一致性较高。结论与二维超声相比,三维超声具有显示斑块立体形态、更准确测量斑块大小的优势,为斑块定量分析提供了一种新的方法。     

剪切波弹性成像评价糖尿病足背部拇短伸肌硬度的价值

目的 探讨剪切波弹性成像(SWE)评价糖尿病足背部拇短伸肌弹性改变的应用价值。方法 收集2型糖尿病(DM)组14例、2型糖尿病合并微血管病变(DM+MC)组16例及正常对照组25例。对正常组SWE测量采用组内相关系数(ICC)及Bland-Altman图进行同一医师及不同医师弹性测量的可重复性及一致性分析;利用剪切波弹性成像(SWE)测量足拇短伸肌的平均杨氏模量值(Emean),有差异则进行事后两两比较。探讨足背部拇短伸肌弹性模量值对不同严重程度糖尿病的诊断价值。结果 同一医师及不同医师SWE测量足拇短伸肌的可重复性及一致性均高,以同一医师最佳(ICC为0.863 7,95%一致性界限的上下限为-1.477SD～1.652SD);足背部拇短伸肌的Emean与糖尿病严重程度呈正相关,Emean在DM+MC组>DM组>正常组,各组间差异均有统计学意义(P<0.05);以DM+MC为诊断结果绘制受试者工作特征曲线,Emean的曲线下面积(AUC)为0.962,灵敏度为87.5%,特异度为89.7%。结论 剪切波弹性成像评价糖尿病足背部骨骼肌弹性改变具有可行性,Emean随着...     

多普勒、M型及四维时空关联成像检测胎儿左心室每搏输出量的对比观察

目的 比较多普勒、M型与四维时空关联成像(STIC)测量胎儿左心每搏输出量的重复性及测量者间的一致性。方法 2名超声科医师采用双盲法分别应用多普勒、M型与四维STIC测定30胎26~30周正常单胎胎儿左心室输出量,计算组内相关系数(ICC),进行Bland-Altman图分析,评估上述测量方法的重复性和测量者间一致性。结果 ①同一测量者用3种方法测定胎儿左心室输出量的差异无统计学意义(P均>0.05);②2名观察者间3种方法测量重复性比较,其ICC值STIC法最高(多普勒法ICC:0.93,95%可信区间:0.86~0.95;M型法ICC:0.89,95%可信区间:0.82~0.91;STIC法ICC:0.95,95%可信区间:0.88~0.97);③应用Bland-Altman分析2名观察者测量的一致性,STIC法的系统偏倚及一致界限较多普勒法和M型法好(多普勒法平均差值:-0.04 ml,95%可信区间-0.22~0.14 ml;M型法平均差值:-0.06 ml,95%可信区间-0.20~0.08 ml;STIC法平均差值:-0.01 ml,95%可信区间-0.11~0.09 ml)。结论 3种方法均可用于测量胎儿左心室输出量,以STIC法测量的可重复性和一致性最高,是一种较好的选择。     

正常成人肝脏声触诊组织量化值的一致性研究

目的探讨不同观察者检测同一健康人群肝脏声触诊组织量化(VTQ)值的相关性和一致性。方法两名超声医师分别对150例健康人群肝脏左右叶进行VTQ检测,比较各观察者的VTQ检测成功率及VTQ值,分析VTQ值的相关性和一致性。结果两名超声医师对肝脏左右叶VTQ检测成功率的比较差异无统计学意义,肝脏左叶VTQ和肝脏右叶VTQ呈高度正相关,相关系数分别为0.902和0.913(P﹤0.01)。Bland-Altman分析肝脏左右叶VTQ均呈现较好一致性,偏倚分别为0.017和0.013,一致性界限分别为-0.225~0.266和-0.224~0.249。结论两名超声医师检测的VTQ值具有高度相关性和较好一致性,说明VTQ技术检测稳定性高,可以作为无创评估肝脏硬度的常规测量方法。     

VTIQ技术评价健康青年人群跟腱弹性的重复性研究

目的探讨声触诊组织量化成像(VTIQ)技术在评价正常健康青年人群跟腱弹性测值的可重复性,分析其在临床的应用价值。方法 4名不同年资医师对采用VTIQ技术定量测量43例健康青年志愿者左侧跟腱(共43条跟腱)剪切波速度。每条跟腱均测量3个不同部位:跟骨上缘上2cm、跟骨上缘1cm及跟腱跟骨附着末端上1cm。同一部位每个医师均测量2次。收集4名医师43条跟腱3个部位两次测量的剪切波速度结果,分别行不同检查者间及同一检查者一致性检验。结果同一检查者同一跟腱部位两次测量间及不同检查者同一跟腱部位测量值之间的差异均无统计学意义。不同检查者间一致性检验的ICC值分别为0.759(跟骨上缘上2cm)、0.712(跟骨上缘1cm)、0.689(跟腱跟骨附着末端上1cm)。结论 VTIQ作为一种新的剪切波定量分析成像技术,在跟腱检查中具有良好的重复性,其重复性高低与其测量部位的选择具有一定关系。     

超声极速成像技术评价烟雾病患者颈动脉血管弹性的临床应用价值

目的 运用超声极速脉搏波(UFPWV)技术测量的脉搏波传导速度(PWV)评价烟雾病(MMD)患者颈动脉僵硬度，探讨UFPWV技术在检测MMD患者颈动脉僵硬度的临床价值。方法 分别选取MMD患者47例(MMD组)和健康者43例(对照组),比较两组一般临床资料、颈动脉的常规超声参数及颈动脉的收缩起始时脉搏波传导速度(PWVBS)、收缩结束时脉搏波传导速度(PWVES)。结果 MMD组的PWVBS和PWVES均大于对照组，差异具有统计学意义(P<0.05)。结论 UFPWV技术能够早期发现MMD患者的颈动脉弹性功能衰减，为临床诊断并早期干预MMD患者颈动脉僵硬度提供依据。     

声辐射力脉冲成像技术检测健康成人髌韧带的可行性研究

目的初步探讨声辐射力脉冲成像(ARFI)技术评价健康成人髌韧带的可行性。方法由两名超声医师分别对44例健康成人的双侧髌韧带行二维超声和ARFI检查,测量髌韧带厚度和纵、横切面近、中、远段的剪切波速度,每一医师对同一受检者测量两次。结果正常成人髌韧带厚度2.89~3.10 mm,平均(2.99±0.33)mm。ARFI技术获得正常髌韧带剪切波速度:同一髌韧带纵、横切面近、中、远段剪切波速度比较差异均有统计学意义(t=5.104、4.392、7.846,均P=0.000),但纵、横切面上同一髌韧带近、中、远段的剪切波速度比较差异均无统计学意义(F=1.252、1.790,P=0.290、0.171)。重复性检测显示ARFI测量具有较高的一致性,组内相关系数为0.78~0.98。结论 ARFI技术能够测量髌韧带的剪切波速度,具有较好的一致性,可以快速、方便地评价髌韧带弹性。     

Carotid–Femoral Pulse Wave Velocity Assessed by Ultrasound: A Study with Echotracking Technology

Described here is a new method for determination of carotid–femoral pulse wave velocity (PWV) based on arterial diameter waveform recording by an ultrasound system. The study was carried out on 120 consecutive patients. Carotid–femoral PWV was determined using a tonometric technique (PWVpp, PulsePen, DiaTecne, Milan, Italy) and an echotracking ultrasound system (PWVet, E-Track, Aloka, Tokyo, Japan). The relationship between PWVpp and PWVet was evaluated by linear regression and Bland–Altman analysis. There was excellent agreement between PWVet and PWVpp (Pearson's r = 0.94, 95% confidence interval: 0.91–0.96, p < 0.0001; PWVet = 0.88 × PWVpp + 0.57). The Bland–Altman plot revealed an offset of ?0.33 m/s with limits of agreement from ?2.21 to 1.54 m/s. The coefficients of variation for within-subject repeatability between PWVet and PWVpp had were 5.79% and 8.47%, respectively, without significant differences in the Bland–Altman analysis. The results suggest that echotracking technology can provide a reliable estimate of aortic stiffness comparable to that of the tonometric techniques.     

血管回声跟踪技术对兔颈动脉弹性的定量评价研究

目的 探讨探头支架辅助的回声跟踪(echo-tracking,ET)技术定量评价早期动脉硬化的可行性、准确性及各弹性参数的敏感性.方法 对39只4月龄健康新西兰白兔随机分为4组,造模1、2、3组及对照组.造模组均饲喂高脂颗粒饲料,对照组饲喂基础颗粒饲料,分别在喂养的0、4、8、12周末,利用探头支架辅助的ET技术测量颈动脉弹性的各项指标:压力-应变弹性系数(Ep)、僵硬度(β)及顺应性(AC)、脉搏波速度(PWV)、膨大指数(AI)等,同时取兔耳缘静脉血进行血脂检查及颈总动脉病理检查,进行对照分析.结果 Ep、β随造模时间的延长逐渐增加,AC随造模时间的延长逐渐减小,造模4周末与基础状态相比、造模8周末与造模4周末相比、造模12周末与造模8周末相比均出现显著变化,差异均有统计学意义(P<0.05);PWV于造模8周末开始较基础状态增高(P<0.05),于造模12周末显著增高且较造模8周末亦显著增高,差异有统计学意义(P<0.01);AI始终无明显变化.结论 ET技术可准确、可靠地评价早期动脉硬化的动脉弹性,而应用探头支架可保持检查过程的稳定性和结果的敏感性、精确性及可重复性.     

Repeatability of the sonographic assessment of fetal sucking and swallowing movements.

OBJECTIVE: To test the repeatability of sonography in the assessment of fetal sucking and swallowing movements. METHODS: Eighty normal fetuses of pregnant women with no systemic abnormalities were examined sonographically at 30-38 weeks of gestation. Sucking and swallowing movements were observed for 15 min and the face was visualized in frontal and lateral views. The examinations were recorded for later analysis by two independent observers and the 95% limits of agreement (Bland and Altman) method was used for inter- and intraobserver comparison. RESULTS: The mean +/- SD number of swallowing movements, sucking bursts and total sucking movements recorded by Observer 1 were 8.3 +/- 4.7, 9.9 +/- 9.3 and 35.8 +/- 48.0 and the equivalent values for Observer 2 were 8.2 +/- 4.8, 9.8 +/- 9.3 and 36.4 +/- 49.0, respectively. The mean (95% limits of agreement) interobserver difference was 0.1 (-1.4; 1.6), 0.1 (-2.2; 2.3) and -0.6 (-9.0; 7.9), and the mean (95% limits of agreement) intraobserver difference was 0.4 (-3.1; 3.9), 0.1 (-2.0; 2.2) and 1.0 (-10.7; 12.7) for swallowing movements, sucking bursts and total sucking movements, respectively. CONCLUSIONS: The high degree of intra- and interobserver repeatability disclosed in the sonographic analysis of fetal sucking and swallowing movements supports the applicability of sonographic assessment in normal fetuses.     

The intra-rater reliability of the balance performance monitor when measuring sitting symmetry and weight-shift activity after stroke in a community setting

OBJECTIVE: To examine the intra-rater reliability of sitting symmetry and weight-shift activity measurements in poststroke adults. DESIGN: An intra-rater reliability study. SETTING: A community setting. SUBJECTS: Adult stroke survivors attending stroke support groups within the community of Nottingham (U.K.). MAIN MEASURES: The Balance Performance Monitor used to measure sitting symmetry and weight-shift activity. Intraclass correlation coefficients (ICCs) and their 95% confidence intervals (95% CI) were calculated. The Bland Altman method for assessing agreement is also presented. RESULTS: We tested 49 participants (median age 73 years; interquartile range 68-81 years). Between-test reliability for sitting symmetry was high: ICC (1,1) = 0.93 (95% CI 0.87 < or = ICC < or = 0.96). The mean difference between the measures (d) was -0.08 (95% CI -0.48 < or = d < or = 0.31); the standard deviation of the differences (SDdiff) was 1.383. The coefficient of repeatability was 2.76; the 95% limits of agreement were -2.850 and 2.682. Between-test reliability for weight-shift activity was also high: ICC (1,1) = 0.86 (95% CI 0.77 < or = ICC < or = 0.92). Bland-Altman d = -0.08 (95% CI -0.19 < or = d < or = 0.35), SDdiff = 0.936. The coefficient of repeatability was 1.87; the 95% limits of agreement were -1.792 and 1.952. CONCLUSIONS: The 95% CI for d for both parameters crossed zero, indicating that between-test bias is unlikely. Sitting symmetry and weight-shift activity measures demonstrated acceptable levels of reliability.     

Development and validation of an in vivo analysis tool to identify changes in carotid plaque tissue types in serial 3-D ultrasound scans

We have developed a three-dimensional (3-D) B-mode acquisition system suitable for imaging carotid plaques in vivo. A texture classification system using 157 statistical and textural algorithms, previously developed in our laboratory and shown to predict the contents of in vitro carotid plaques, was applied to in vivo 3-D image sets obtained from patients with both symptomatic and asymptomatic carotid artery plaques. Delineation of plaque boundaries is more difficult using in vivo images than in vitro images of excised plaques embedded in agar. This study has examined inter- and intraobserver variability studies to assess the degree of selectivity of the plaque region-of-interest (ROI) and assess the degree of repeatability for potential use in comparing serial scans. An interobserver limit of agreement of +/-12.9% and an intraobserver limit of repeatability of <2% were obtained. These results show that the plaque ROI selection is subjective, but is repeatable within acceptable limits.     

Inter-Scan Reproducibility of Carotid Plaque Volume Measurements by 3-D Ultrasound

We tested a novel 3-D matrix transducer with respect to inter-scan reproducibility of carotid maximum plaque thickness (MPT) and volume measurements. To improve reproducibility while focusing on the largest plaque/most diseased part of the carotid artery, we introduced a new partial plaque volume (PPV) measure centered on MPT. Total plaque volume (TPV), PPV from a 10-mm segment and MPT were measured using dedicated semi-automated software on 38 plaques from 26 patients. Inter-scan reproducibility was assessed using the t-test, Bland–Altman plots and Pearson's correlation coefficient. There was a mean difference of 0.01?mm in MPT (limits of agreement: ?0.45 to 0.42?mm, Pearson's correlation coefficient: 0.96). Both volume measurements exhibited high reproducibility, with PPV being superior (limits of agreement: ?35.3?mm³ to 33.5?mm³, Pearson's correlation coefficient: 0.96) to TPV (limits of agreement: ?88.2 to 61.5?mm³, Pearson's correlation coefficient: 0.91). The good reproducibility revealed by the present results encourages future studies on establishing plaque quantification as part of cardiovascular risk assessment and for follow-up of disease progression over time.     

Noninvasive Estimation of the Blood Pressure Waveform in the Carotid Artery Using Continuous Finger Blood Pressure Monitoring

To noninvasively estimate the blood pressure continuously in the common carotid artery (CCA), we obtained the distension waveform of the CCA from seven healthy volunteers and 20 hypertensive patients using radio-frequency ultrasound. Consequently, it was calibrated by the mean and diastolic pressure measured in the finger artery and compared with applanation tonometry, calibrated using the systolic and diastolic pressure in the brachial artery. The mean difference in estimating the mean blood pressure was 0.3 mm Hg (limits of agreement: –11.7 to 12.3 mm Hg). In estimating the systolic blood pressure, the mean difference was 8.0 mm Hg (limits of agreement: –29.8 to 45.8 mm Hg) and showed increasing variation with blood pressure. The systolic blood pressure values can be expected between 0.83 and 1.35 times the control method. In this study, we obtained proof-of-principle for noninvasively measuring blood pressure in the CCA using continuous finger blood pressure monitoring. This opens the way to estimating location specific arterial stiffness and intra-plaque elasticity.     

颈动脉粥样硬化的超声研究进展

随着速度向量成像（VVI）、血管回声跟踪（ET）及超声造影等技术的开展,超声在测定颈动脉内-中膜厚度、颈动脉弹性及斑块稳定性方面取得了重大进展。超声检查能准确反映颈动脉结构及功能改变,评价动脉粥样硬化病变程度,预测心脑血管等疾病的发生发展,为临床诊断及治疗提供可靠依据。     

Comparison of Laboratory Values Obtained by Phlebotomy versus Saline Lock Devices

Objectives To assess the utility of a peripheral saline lock device (SLD) as an alternative to a second venipuncture for obtaining selected blood samples. Methods This prospective study used a comparative design and was conducted in an urban emergency department (ED). Adult patients with an existing SLD in place who required serial phlebotomy were eligible for inclusion in the study. Each subject had blood samples obtained by venipuncture (control) with a Vacutainer adapter according to standard protocols. Within 5 minutes of obtaining the control samples, a sample was obtained from the patients' SLDs; a tourniquet was applied proximal to the intravenous line, a 5‐mL waste portion was obtained, and a Vacutainer adapter was placed to draw specimens for testing. Each of the paired samples was analyzed for hematocrit, electrolytes, and cardiac enzymes. The Bland‐Altman method was used to analyze the concordance between each pair of measurements. Paired t‐tests for each of the eight laboratory tests were used to assess whether the values were statistically different from each other. The 95% limits of agreement around the mean differences were calculated. Differences between SLD aspirates and venipuncture aspirates also were compared with the federal regulatory standards that ensure reliable and accurate laboratory testing. Results Eighty‐one patients were eligible for the study; in 73 (90.1%; 95% confidence interval [CI] = 81.5% to 95.6%) of the patients, the SLD could be aspirated for testing. The paired t‐tests indicated that there were no statistically significant differences between the mean values of the two methods of testing. Of the 584 paired values analyzed, 35 (6.0%; 95% CI = 4.3% to 8.2%) exceeded the Bland‐Altman limits of agreement, and 43 (7.4%; 95% CI = 5.4% to 9.8%) fell outside the acceptable range determined by the federal regulation of clinical laboratories. Of those values that exceeded the acceptable Bland‐Altman limits of agreement, none would have resulted in clinical intervention. Conclusions Aspirating blood via an SLD is an acceptable method of obtaining serial laboratory values in a group of stable, consenting adult ED patients.     

NexTemp thermometer can be used interchangeably with tympanic or mercury thermometers for emergency department use

Objectives To determine the agreement between the chemical dot NexTemp thermometer with mercury and tympanic thermometers and the repeatability of measurements using these devices. Methods A prospective study involving a convenience sample of 194 consenting adult patients presenting to the ED, Freemasons Hospital, East Melbourne, Victoria, Australia. A survey of emergency medical staff was conducted to determine what they considered an acceptable level of agreement and repeatability for a putative new thermometer. The NexTemp thermometer’s performance was judged against this. For each thermometer, a set of two temperature measurements was made in every patient. The sequence of the set of readings (and hence device) was random between patients and the staff member performing one set was blinded to the results of the other two sets of readings in each patient. The method of Bland and Altman was used for assessing agreement and repeatability. Results Clinicians considered that a new thermometer should exhibit repeatability of ±0.3°C and agree with existing devices within ±0.5°C. The tympanic thermometer had 95% limits of repeatability of ?0.8–0.5°C compared with the NexTemp (?0.3–0.4°C) and mercury thermometers (?0.3–0.4°C). The NexTemp thermometer agreed with mercury thermometer within ?0.6–0.5°C. The tympanic thermometer agreed with the mercury thermometer within ?1.0–1.1°C. Conclusion Based on temperature measurement only, the NexTemp thermometer can be used interchangeably with current mercury and tympanic thermometers.