Department of Radiology, Pritzker School of Medicine, The University of Chicago, MC 2026, Chicago, IL 60637, USA.
AJR Am J Roentgenol. 2009 Dec;193(6):1561-7. doi: 10.2214/AJR.09.2618.
The purpose of this study was to evaluate the reliability of polyp measurements at CT colonography and the factors that affect the measurements.
Fifty colonoscopically proven cases of polyps 6 mm in diameter or larger were analyzed by two observers who measured each polyp in supine and prone views. Manual measurements of 2D volume by summation of areas, 2D maximum diameter, and 3D maximum diameter and automated measurements of 3D maximum diameter and volume were recorded for each observer and were repeated for one of the observers. Intraobserver and interobserver agreement was calculated. Analysis was performed to determine the measurement parameter that correlated most with summation-of-areas volume. Supine and prone measurements as a surrogate for tracking change in polyp size over time were analyzed to determine the measurement parameter with the least variation.
Maximum diameter measured manually on 3D images had the highest correlation with summation-of-areas volume. Manual summation-of-areas volume was found to have the least variation between supine and prone measurements.
Linear polyp measurement in the 3D endoluminal view appears to be the most reliable parameter for use in the decision to excise a polyp according to current guidelines. In our study, manual calculation of volume with summation of areas was found to be the most reliable measurement parameter for observing polyp growth over serial examinations. High reliability of polyp measurements is essential for adequate assessment of change in polyp size over serial examinations because many patients with intermediate-size polyps are expected to choose surveillance.
本研究旨在评估 CT 结肠成像中息肉测量的可靠性以及影响测量的因素。
对 50 例经结肠镜证实的直径≥6mm 的息肉进行分析，由 2 名观察者分别在仰卧位和俯卧位观察每个息肉。记录每位观察者手动测量的 2D 面积总和、2D 最大直径、3D 最大直径和 3D 体积，以及 1 名观察者重复的自动测量 3D 最大直径和体积。计算观察者内和观察者间的一致性。分析确定与面积总和体积相关性最高的测量参数。分析仰卧位和俯卧位测量作为随时间追踪息肉大小变化的替代方法，以确定变化最小的测量参数。
手动测量的 3D 图像最大直径与面积总和体积相关性最高。仰卧位和俯卧位测量的手动面积总和体积之间的变化最小。
根据目前的指南，在 3D 腔内视图中线性测量息肉似乎是切除息肉的最可靠参数。在我们的研究中，发现手动计算面积总和的体积是观察系列检查中息肉生长的最可靠测量参数。息肉测量的高可靠性对于充分评估系列检查中息肉大小的变化至关重要，因为许多中等大小息肉的患者预计会选择监测。
