摘要
通过颈动脉狭窄的CTA与DSA对照,探讨自动三维CTA血管分析软件的可重复性。材料和方法36例症状性颈动脉狭窄患者行CTA和DSA检查,其中31例患者33条颈动脉行旋转DSA成像。所有36例患者的72条颈动脉均采用多层螺旋CT行CT血管成像,扫描参数为层厚1mm,进床速度5mm/s,重建层厚1mm。两位放射科医生根据NASCET标准分别对3DCTA和MPRDSA图像进行测量,首先自动测量,利用CTA自动生成软件测量狭窄的程度,随后在有钙化、溃疡、邻近血管等干扰因素时行手动矫正测量。结果CTA观察者内和观察者间相关性为0.89和0.90(P<0.01),MPRrDSA观察者间的相关性为0.90(P<0.01);自动测量CTA和rDSA观察者相关性为0.69(P<0.01),手动测量时增加到0.81(P<0.01),颈动脉狭窄有干扰因素时比没有干扰因素时测量的相关性显著降低。结论自动3DCTA具有高度的可重复性,手动矫正测量法避免钙化、溃疡、邻近血管等干扰因素,因而增加CTA与MPRrDSA的一致性。
Purpose:To assess the reproducibility of automated3D CT-angiography analysis software in the evalˉuation of carotid artery stenosis with reference to rotational DSA(rDSA).Materials and Methods:Seventy-two vessels in36patients with symptomatic carotid stenosis were evaluated by3D CT-anˉgiography and DSA.Thirty-one patients also underwent rotational3D-DSA(rDSA).Multislice CT was performed with bolus tracking and slice thickness of1.5mm(1mm collimation,feed5mm/s)and reconˉstruction interval of1.0mm.Two observers independently performed the stenosis measurements on3D CTA and on MPR rDSA according to the NASCET criteria.The first measurements on CTA utilized an analysis program with automatic stenosis recognition and quantitation.In the subsequent measurements,manual corrections were applied when necessary.Interfering factors for stenosis quantitation,such as calcifications,ulcerations and adjacent vessels,were registered.Results:Intraobserver and interobˉserver correlation for CTA were0.89and0.90,respectively.(P<0.001).The interobserver correlation between two observers for MPR rDSA was0.90(P<0.001).The intertechnique correlation between CTA and rDSA was0.69(P<0.001)using automatic measurements,but increased to0.81(P<0.001)with the manually corrected measurements.Automatic stenosis recognition achieved a markedly poorer correlaˉtion with MPR rDSA in carotids with interfering factors than those in cases where there were no such factors.Conclusion:Automated3D CT-angiography analysis methods are highly reproducible.Manuˉally corrected measurements facilitated avoidance of the interfering factors,such as ulcerations,calcifiˉcations and adjacent vessels,and thus increased agreement between CT-angiography and MPR rDSA.
出处
《中国医学计算机成像杂志》
CSCD
2004年第3期149-154,共6页
Chinese Computed Medical Imaging
