Assessment of interstitial lung disease severity using lung ultrasound and its correlation with high-resolution computed tomography findings and functional status: a cross-sectional study
Abstract
Owing to its ability to accurately characterize parenchymal involvement, high-resolution computed tomography (HRCT) is the cornerstone imaging modality for the evaluation of interstitial lung diseases (ILD). Although highly informative, its use is limited by radiation exposure and the challenges of repeated imaging. Recently, lung ultrasound (LUS) has gained importance as a bedside tool for assessing interstitial involvement using B-lines. We aimed to evaluate the correlation between LUS B-line scores and HRCT visual severity score in patients with ILD, and to investigate their associations with pulmonary function, exercise capacity, and health-related quality of life (HRQoL). Fifty adult patients diagnosed with ILD were enrolled in a prospective cross-sectional study. Participants underwent clinical assessment, HRCT visual scoring, LUS using a quantitative B-line score, spirometry, arterial blood gas analysis, echocardiography, 6-min walk test, and HRQoL assessment using the Saint George’s Respiratory Questionnaire. Correlations between imaging scores, physiological parameters, exercise capacity, and HRQoL were analyzed. The study included 50 patients (mean age: 50.3 ± 15 years; 72% female). Connective tissue disease-associated ILD was the most common subtype (36%), followed by idiopathic pulmonary fibrosis (26%), nonspecific interstitial pneumonia (22%), and hypersensitivity pneumonitis (12%). Total LUS B-line scores demonstrated a pronounced positive correlation with HRCT visual severity scores ( r =0.631, P <0.001). Higher HRCT scores were also significantly associated with worse Saint George’s Respiratory Questionnaire scores, consistent with reduced HRQoL. LUS B-line score demonstrated a strong association with HRCT severity and may serve as a complementary tool in the assessment of disease severity in patients with ILD.