CT Imaging-Based Low-Attenuation Super Clusters in Three Dimensions and the Progression of Emphysema

摘要: Background Distributions of low-attenuation areas in two-dimensional (2-D) CT lung slices are used to quantify parenchymal destruction patients with COPD. However, these segmental approaches limited and may not reflect the true three-dimensional (3-D) tissue processes that drive emphysematous changes lung. The goal this study was instead evaluate distributions 3-D volumes, which we hypothesized would follow a power law distribution provide more complete assessment mechanisms underlying disease progression. Methods scans pulmonary function test results were acquired from an observational database for N = 12 COPD control patients. data set included baseline two annual follow-up evaluations Three-dimensional representations lungs reconstructed 2-D axial slices, volumes identified as contiguous voxels  Results Low-attenuation sizes generally followed distribution, exception large, individual outliers termed "super clusters," deviated expected distribution. Super cluster volume correlated severity (% total low attenuation, ρ = 0.950) clinical measures including FEV1 (ρ = –0.849) diffusing capacity carbon monoxide Dlco –0.874). To interpret these results, developed personalized computational model super emergence. Simulations indicated progression likely occur near existing regions, giving rise biomechanical, force-induced mechanism growth. Conclusions clusters defining, quantitative features dominate progression, particularly advanced