Functional Respiratory Imaging (FRI) shows significant regional ventilation defects in COPD patients as compared to healthy data

Introduction: Ventilation defects in chronic obstructive pulmonary disease (COPD) are associated with reduced exercise tolerance and worse quality of life. Standard lung function tests lack the ability to detect and quantify regional ventilation defects often resulting in sub-optimal treatment. For the first time, the current study uses high-resolution FRI to quantify and visualize ventilation defects in COPD and compared them to a healthy population. Materials & Methods: Regional ventilation data derived from gated inspiratory/expiratory HRCT scans is assessed in 3 healthy and 3 matched COPD patients (4M/2F, 64±3 years, 173±2 cm). Lobar ventilation is calculated and compared between healthy and COPD. Results: The right upper lobe of a COPD patient as compared to a matched healthy patient shows a decrease of 21.8±8.5%, the right middle lobe a decrease of 21.8±4.5%, the right lower lobe a decrease of 26.6±8.0%, the left upper lobe a decrease of 21.2±11.6% and the left lower lobe a decrease of 25.6±12.3%. Conclusion: Ventilation defects express themselves in a heterogeneous manner in COPD patients. Lower lobes appear to be more affected by the disease, resulting in an overall larger reduction in ventilation as compared to the upper lobes. These findings are particularly relevant when optimizing inhalation therapies that rely on inspiratory airflow to ensure adequate drug delivery to the lung.