感兴趣区的选择对周围型肺癌CT灌注参数的影响

摘要

目的 探讨CT灌注后感兴趣区(ROI)的选择对周围型肺癌64层CT灌注参数可重复性的影响.资料与方法 回顾性分析37例周围型肺癌患者64层CT灌注的图像,重复测量最大面积勾勒法(ROIm)、最大面积画圈法(ROIr)及仿体积法(ROIv)所得灌注参数,包括血流量(BF)、血容量(BV)、Patlak血容量(PBV)、表面通透性(PS)及平均通过时间(MTT),分析3种不同ROI选择方法所得各参数在同一观察者内及不同观察者间测定的可重复性,并比较不同ROI的稳定性.结果 3种不同ROI所获得的灌注参数在观察者内和观察者间均表现为较高的一致性(ICC＞0.75).此外,不同ROI选择方法所得灌注参数间差异无统计学意义(p＞0.05),但ROIm与ROIv所得灌注参数较ROIr所得灌注参数稳定.结论 3种不同ROI选择方法所得灌注参数可重复性较好,但ROIm与ROIv较ROIr更适合评价周围型肺癌的血流灌注情况.%Purpose To investigate the influence of the region of interest (ROI) selection on the repeatability of 64 slice spiral CT perfusion parameters for the peripheral lung cancer.Materials and Methods The 64 slice spiral CT perfusion images of thirty-seven patients with peripheral lung cancer were retrospectively analyzed.The perfusion parameters including blood flow (BF),blood volume (BV),Patlak blood volume (PBV),permeability surface area product (PS),and mean transit time (MTT) were obtained by using three ROI selection methods including maximum area of ROI (ROIm),round of ROI (ROIr),and volume of ROI (ROLv),and these parameters were measured by two observers repeatedly.The repeatability and reliability of the values of these perfusion parameters by using different ROI methods or measured by different observer were determined.Results The perfusion parameters derived from three ROIs all had a excellent intraobserver and interobserver agreement (ICC＞0.75).Besides,the values of the perfusion parameters by using different ROI methods had no significant difference (P＞0.05),but the data obtained by ROIm and ROIv were more stable than that obtained by ROIr.Conclusion The repeatability of the perfusion parameters obtained from above three ROIs is excellent,but ROIm and ROIv may be more suitable than ROIr to assess vascular perfusion of peripheral lung cancer.