Abstract
Purpose:
To investigate whether CT-based histograms of attenuation on inspiration and expiration can indicate alveolar collapse and predict progression in patients with idiopathic pulmonary fibrosis (IPF).
Methods:
In this retrospective study, CT scans of IPF patients imaged in the inspiratory and expiratory phases were analyzed. Patients were divided into two groups based on their status three years after baseline CT (death/transplantation or clinical surveillance). Attenuation histograms were analyzed, and the Mann-Whitney U test was used to assess differences between groups in CT-derived measures (including skewness). Logistic regression was used to model the ability to discriminate between groups using forced vital capacity (FVC%) and CT-derived measures.
Results:
The study included 66 patients (mean age 69.5 ± 10.9 years, 58 men). After three years, 37 patients had survived and 29 had either died or received a transplant. Significant differences between groups were found in all CT-derived measures and baseline FVC%. A logistic regression model using CT-derived skewness had better predictive performance (AUC = 0.793, 95% CI = 0.685-0.900) than the FVC% model alone (0.708, 0.581–0.836).
Conclusion:
Paired inspiratory/expiratory attenuation histogram analysis improves outcome prediction beyond FVC% alone and offers a promising approach to assess alveolar collapse in IPF as a prognostic imaging marker.