Elatrozy T, Nicolaides A, Tegos T, Zarka A Z, Griffin M, Sabetai M
Irvine Laboratory for Cardiovascular Investigation, Imperial College School of Medicine, St. Mary's Hospital, London, UK.
Int Angiol. 1998 Sep;17(3):179-86.
To develop a method that allows B-mode ultrasonic images of carotid plaques to be standardised so that measurements of plaque echodensity become comparable and clinically useful.
Design. Cross sectional study. Setting. Teaching hospital, England.
a random consecutive series of 23 patients in part I, 19 in part II and 77 in part III. Measures. Part I: twenty-three images of carotid bifurcation plaques from 2 duplex scanners were digitised. Images were standardised by 4 observers so that the grey scale median (GSM) would be 0-5 for blood and 185-195 for adventitia. Part II: the effect of three different recording media: video, magneto-optical disk (MOD) and thermal paper on the echodensity of 19 plaques' images was determined. Part III: the echodensity of 91 carotid bifurcation plaques with greater than 50% stenosis was correlated to the presence or absence of ipsilateral hemispherical symptoms.
Part I: the coefficient of variation (CV) among 4 observers was 0.7%, 0% and 4.7% after image standardisation for the adventitia, blood and plaques respectively. Part II: a near perfect agreement was obtained between the GSM of plaques from images on video and MOD (r = 0.97) after standardisation. Part III: after standardisation, the GSM of symptomatic plaques was lower (21 +/- 14.8) than in asymptomatic plaques (38 +/- 26) p = 0.002. Plaque echolucency was more likely to be associated with symptoms (relative risk 4.1 90% CI 1.8-9.4).
Images from different scanners by different ultrasonographers and through different peripherals can be standardised so that measurements of plaque echodensity may become comparable. The method is recommended for use in future natural history studies on carotid plaques where stroke is the end-point.
开发一种方法，使颈动脉斑块的B型超声图像标准化，以便斑块回声密度测量结果具有可比性且对临床有用。
设计。横断面研究。地点。英国的教学医院。
第一部分为23例患者的随机连续系列，第二部分为19例，第三部分为77例。测量。第一部分：对来自2台双功扫描仪的23张颈动脉分叉处斑块图像进行数字化处理。4名观察者将图像标准化，使血液的灰度中位数（GSM）为0 - 5，外膜为185 - 195。第二部分：确定三种不同记录介质（视频、磁光盘（MOD）和热敏纸）对19个斑块图像回声密度的影响。第三部分：对91个狭窄程度大于50%的颈动脉分叉处斑块的回声密度与同侧半球症状的有无进行相关性分析。
第一部分：图像标准化后，4名观察者对外膜、血液和斑块的变异系数（CV）分别为0.7%、0%和4.7%。第二部分：标准化后，视频和MOD上图像的斑块GSM之间获得了近乎完美的一致性（r = 0.97）。第三部分：标准化后，有症状斑块的GSM（21±14.8）低于无症状斑块（38±26）（p = 0.002）。斑块的透声性更可能与症状相关（相对风险4.1，90%可信区间1.8 - 9.4）。
不同超声检查者通过不同扫描仪并使用不同周边设备获取的图像可以标准化，从而使斑块回声密度测量结果具有可比性。该方法推荐用于未来以中风为终点的颈动脉斑块自然史研究。
