The Intra-observer Variability of Volumetric Measurement of Pulmonary Nodules:Comparison of Two-dimensional and Three-dimensional Method
10.3779/j.issn.1009-3419.2014.04.08
- VernacularTitle:肺结节二维与三维体积测量的观察者内重复性比较
- Author:
GUO XIAOWAN
1
;
WANG YING
;
LI DONG
;
ZHANG CHONG
;
CAO YANG
;
SU DATONG
;
YU TIELIAN
Author Information
1. 天津医科大学总医院放射科
- Keywords:
Pulmonary nodule;
Computed tomography;
Volumetric measurement;
Repeatability
- From:
Chinese Journal of Lung Cancer
2014;(4):336-341
- CountryChina
- Language:Chinese
-
Abstract:
Background and objective Sotfware oriented three-dimensional (3D) volumetric measurement of pul-monary nodules has been feasible in the follow-up of indeterminate pulmonary nodules, however, its value need a further vali-dation. hTe purpose of this study is to retrospectively analyze the chest CT data of patients with pulmonary nodules to compare the intra-observer variability of 3D and two-dimensional (2D) volumetric measurement. Methods Eighty-six pulmonary nod-ules in chest CT scans of 79 subjects were retrospectively analyzed. One radiologist measured the nodules twice with a 7 days interval using 2D and 3D methods respectively. hTe maximal diameter (X), the perpendicular diameter (Y) on maximal cross sectional area of the nodule and the caudo-cranial diameter (Z) were measured and the volume was calculated by two models:spherical and elliptical model. hTe 3D measurements were acquired with semi-automated sotfware with manual adjustment on unsatisifed nodule segmentation. Logistic regression analysis was performed to evaluate the effect of nodule location and mor-phology on 3D nodule segmentation. ANOVA and correlation test were used to evaluate the difference among three methods. Bland-Altman method was applied to quantify the intra-observer variability. Results Sotfware achieved satisifed segmentation for 86.4%nodules. hTe irregular and juxtavacular nodules have signiifcantly high odds rations (OR) of unsatisifed segmenta-tion as 4.0, 4.5, respectively. hTe volume measured by three method was signiifcantly different (F=6.5, P=0.012), while the repeated measurements did not led to signiifcant difference (F=1.813, P=0.182). hTe Spearman correlation effcient between 3D volume and 2D volume with sphere and ellipsoid model was 0.97, 0.88. hTe 95%limits of agreement of RD between two repeated measurements were-14%-11.6%,-37.7%-39.9%and-39.8%-45.8%for 3D, 2D with elliptical model and spherical model, respectively. Conclusion hTe 3D volume measurement of pulmonary nodules is more repeatable than 2D volume measurement. Unsatisifed segmentation can occurred on a small number of nodules, especially for irregular and juxtavascular nodules. For these nodules, the measurement of 3D diameters is recommended.
