Abstract
OBJECTIVE: To determine the predictive value of quantitative CT-derived emphysema heterogeneity for clinical response to bronchoscopic lung volume reduction (BLVR). METHODS: This retrospective study included 150 patients who underwent bronchoscopic lung volume reduction (BLVR) between January 2023 and November 2025, of whom 82 were responders and 68 were non-responders. The primary endpoint was the BLVR outcome at 6 months post-procedure, defined as a 15% improvement in forced expiratory volume in one second (FEV1) or a 450 mL improvement in target lobe volume. Secondary endpoints included changes in Chronic Obstructive Lung Disease Assessment Test score, modified Medical Research Council dyspnea score, carbon monoxide diffusion capacity (DLCO), and 6-minute walk test (6MWT). Quantitative CT measurements such as emphysema heterogeneity index (EHI), low attenuation area percentage (LAA%), lung fissure integrity, and air trapping heterogeneity were used as baseline lung structural pmeasures. Multivariate logistic regression analysis was used to identify independent predictors of treatment response. RESULTS: Responders exhibited significantly greater heterogeneity in emphysema: higher EHI, more significant differences in lobar destruction, and a higher proportion of heterogeneous voxels (all P<0.001). Structural parameters also differentiated responders, with responders showing more pronounced lobar volume asymmetry, higher target lobe destruction rate, and decreased vascular density (all P<0.001). Functional quantitative CT revealed markedly higher heterogeneity in air retention (P<0.001), more pronounced ventilation asymmetry (P<0.001), and larger gas retention clusters (all P<0.001) in responders. Responders also had more intact lung fissures and a lower probability of collateral ventilation (both P<0.001). Better preservation of airway morphology was observed, characterized by thinner airway walls (P<0.01), larger lumens (P<0.001), and a greater number of airways (P<0.001). Multivariate analysis showed that the EHI (OR 0.114, P<0.001), ≥90% integrity of the lung fissure (OR 0.888, P<0.001), and immediate target lobe volume reduction ≥700 mL (OR 0.106, P<0.001) were independent predictors of BLVR response. CONCLUSION: Quantitative CT-derived assessment of emphysema heterogeneity provides a strong and clinically significant predictor of treatment response to bronchoscopic lung volume reduction.