VOCAL软件不同轮廓取样方法测量宫颈癌血管参数的重复性比较

目的 以宫颈癌为研究模型,运用三维能量多普勒和计算机辅助分析(VOCAL)软件,比较其手动描绘法和球自动法轮廓取样的重复性.方法 观察者1运用该技术前瞻性分析80名宫颈癌患者,分别使用手动描绘法和球自动法二次测量目标器官内各血管参数,包括血管形成指数(VI)、血流指数(FI)、血管血流指数(VFI).随机选取40名患者由观察者2进行二次测量,分别用手动描绘法和球自动法分析,方法同前.计算组问重复性、组内重复性,一致性范围、95%可信区间,并用ANOVA法分析测量变量和组间测量结果差别的关系.结果 每位观察者各自手动描绘法的重复性均优于球自动法(0.92～0.99对0.75～0.94),手动描绘法与球自动法比较,其标准偏差小,一致性区间窄,95%可信区间窄,相关系数高.手动描绘法组间重复性与组内重复性相当(0.95～0.97对0.92～0.99),而球自动法组间重复性明显降低(0.52～0.72).结论 对于目标器官内血管的测定手动描绘轮廓取样法测量结果较球自动轮廓取样法更稳定,重复性更好,尤其适用于不规则组织的测量.

Comparison of reproducibility of different contour methods in measuring vascularization of cervical carcinoma with VOCAL system

Objective To assess the reproducibility of vascularization measurement in cervical carcinoma using transvaginal three-dimensional power Doppler angiography (3D-PDA) with virtualorgan computer-aided analysis ( VOCAL), and compare the reproducibility of two different contour mode (manual and automatic mode) of VOCAL. Methods Eighty patients with cervical carcinoma were examined by observer 1 using transvaginal 3D-PDA. The two acquired volume datasets were analyzed using manual and sphere automatic contour mode of the VOCAL imaging program for assessing carcinoma vascularization index( VI), flow index(FI), and vascularization flow index(VFI). Forty patients of them were examined randomly by observer 2 by the same method. Reproducibility of vascularity measurement was assessed by calculating intraclass (intra-CC) and interclass (inter-CC) , limits of agreement, 95% confidence interval definition. The contribution of various factors (examiner, measurement, contour mode and patient) to intrasubject variance was estimated using different analysis of variance models (ANOVA). Results For intraobserver,manual contour mode was more valid than sphere automatic contour mode for each observer (0. 92～0. 99 vs 0. 75～0. 94) ,and it also had smaller standard deviation,narrower limit of agreement range, 95% confidence interval and higher intra-cc than those of sphere automatic contour mode. Interobserver agreement of manual contour vascular measurements was similar to the intraobserver agreement for manual contour vascular measurements ( 0. 89 ～ 0. 97 vs 0. 92 ～ 0. 99 ) , but interobserver agreement for sphere automatic contour vascular measurements dramatically reduced (0. 52～0. 72). Conclusions Manual contour mode for 3D-PDA vascular measurement has better reproduciblity than sphere automatic contour mode, especially useful for irregular shape tissue.