Department of Radiology, Seoul National University Hospital, 101 Daehangno, Jongno-gu, Seoul 110-744, Korea.
AJR Am J Roentgenol. 2013 Jun;200(6):W603-9. doi: 10.2214/AJR.12.9458.
The purpose of this study was to determine whether measurement reproducibility can be improved using computerized motion correction and whole-tumor coverage in adaptive 4D perfusion CT of lung cancer.
Perfusion CT covering the entire z-axis of a mass was performed of 40 patients with lung cancer. Each perfusion CT study was performed in 93.5 seconds and included 17 repeated dynamic CT scans obtained using the Adaptive 4D Spiral mode. Tumor blood flow (BF), blood volume (BV), and permeability were measured in four different manners: in the entire tumor (whole-tumor coverage) without the use of motion correction; in the entire tumor with motion correction; in a small volume of interest (VOI) of tumor without motion correction; and in a small VOI with motion correction. Intra- and interobserver reproducibility were assessed through Bland-Altman analyses.
The 95% limits of intraobserver reproducibility for BF, BV, and permeability were as follows: -52.1% to 48.0%, -22.4% to 27.8%, and -33.2% to 38.5%, respectively, in the whole tumor without motion correction; -53.3% to 45.6%, -17.7% to 20.6%, and -31.5% to 37.0% in the whole tumor with motion correction; -107.8% to 97.4%, -98.3% to 93.7%, and -132.3% to 100.7% in a small VOI of tumor without motion correction; and -74.9% to 98.6%, -74.5% to 88.1%, and -109.8% to 114.1% in a small VOI with motion correction. The 95% limits of interobserver reproducibility for BF, BV, and permeability were as follows: -57.0% to 62.5%, -36.8% to 52.6%, and -47.7% to 66.0%, respectively, in the whole tumor without motion correction; -55.7% to 55.8%, -25.8% to 42.0%, and -35.3% to 46.7% in the whole tumor with motion correction; -146.6% to 165.1%, -117.1% to 137.7%, and -143.2% to 149.8% in a small VOI of tumor without motion correction; and -106.2% to 133.6%, -99.5% to 122.4%, and -108.6% to 170.0% in a small VOI of tumor with motion correction. Overall, the best reproducibility was obtained when measurements were obtained in the entire tumor (i.e., whole-tumor coverage) and when motion correction was used.
Measurement reproducibility of perfusion parameters improved when measurements in the entire tumor (i.e., whole-tumor coverage) were obtained and computerized motion correction was used. The best reproducibility in parameter values was obtained with motion correction and whole-tumor coverage.
本研究旨在确定在肺癌自适应 4D 灌注 CT 中使用计算机运动校正和全肿瘤覆盖是否可以提高测量的可重复性。
对 40 例肺癌患者进行了全轴肺肿瘤灌注 CT 检查。每次灌注 CT 研究均在 93.5 秒内完成，包括使用自适应 4D 螺旋模式获得的 17 次重复动态 CT 扫描。在四种不同的方式下测量肿瘤的血流（BF）、血容量（BV）和通透性：不使用运动校正的整个肿瘤（全肿瘤覆盖）；使用运动校正的整个肿瘤；无运动校正的小肿瘤感兴趣区（VOI）；和使用运动校正的小 VOI。通过 Bland-Altman 分析评估了观察者内和观察者间的可重复性。
BF、BV 和通透性的观察者内可重复性的 95% 限值如下：在无运动校正的整个肿瘤中分别为 -52.1% 至 48.0%、-22.4% 至 27.8% 和-33.2% 至 38.5%；在整个肿瘤中有运动校正的情况下分别为-53.3% 至 45.6%、-17.7% 至 20.6% 和-31.5% 至 37.0%；在无运动校正的小肿瘤 VOI 中分别为-107.8% 至 97.4%、-98.3% 至 93.7% 和-132.3% 至 100.7%；在有运动校正的小肿瘤 VOI 中分别为-74.9% 至 98.6%、-74.5% 至 88.1% 和-109.8% 至 114.1%。BF、BV 和通透性的观察者间可重复性的 95% 限值如下：在无运动校正的整个肿瘤中分别为-57.0% 至 62.5%、-36.8% 至 52.6% 和-47.7% 至 66.0%；在整个肿瘤中有运动校正的情况下分别为-55.7% 至 55.8%、-25.8% 至 42.0% 和-35.3% 至 46.7%；在无运动校正的小肿瘤 VOI 中分别为-146.6% 至 165.1%、-117.1% 至 137.7% 和-143.2% 至 149.8%；在有运动校正的小肿瘤 VOI 中分别为-106.2% 至 133.6%、-99.5% 至 122.4% 和-108.6% 至 170.0%。总体而言，当在整个肿瘤（即全肿瘤覆盖）中获得测量值并且使用计算机化运动校正时，灌注参数的测量可重复性得到改善。在参数值方面，最佳的可重复性是使用运动校正和全肿瘤覆盖获得的。
