Distribution of fissure integrity and emphysema measurements by GOLD stages

Abstract

Background: Objective characterization of the magnitude and extent of fissure completeness and emphysematous disease at various stages of COPD is critical to select best therapeutic options. Objective: Determine distribution of fissure integrity (FI) and quantitative CT (QCT) measurements of emphysema by GOLD stages. Methods: 249 patients at various stages of COPD disease (Gold 0: 20, Gold 1: 36, Gold 2: 35, Gold 3: 89, Gold 4: 69) were collected from two institutions (Iowa Comprehensive Lung Imaging Center, Heidelberg Thoraxklinik). 92 QCT measurements of lung volume, emphysema, heterogeneity score, and FI were extracted across the lungs and analyzed using Apollo® software (VIDA Diagnostics, IA). One-way ANOVA analysis was conducted to determine QCT measurements with significant changes across GOLD stages. The distribution of patients in terms of gender and height was homogenous across GOLD stages (p>0.30). GOLD-4 population was on average younger than the other sub-populations (64 yrs, p Results: Lung volumes increased significantly at GOLD3-4 stages. QCT measurements of emphysema were significantly different between all GOLD stages, except between Gold-1 and Gold-2. Completeness of fissures in the right lung was significantly different between GOLD-4 and early COPD stages (RUL: Gold-4≠Gold1-3, p=0.009; RLL: Gold-4≠Gold-1, p=0.02; RH: Gold-4≠Gold-0, p=0.006). No significant changes were observed for FI in the left lung and emphysema heterogeneity across GOLD stages. Conclusion: Greater prevalence of incomplete fissure was associated with late stage COPD, and was only observed in the right lung. These findings have implications on the selection of therapeutic options for emphysema patients.