A quantitative analysis of long-term follow-up computed tomography of idiopathic pulmonary fibrosis: the correlation with the progression and prognosis.

ABSTRACT

BACKGROUND: Quantitative analyses of computed tomography (CT) images using computer-aided detection (CAD) are correlated with visual assessments and pulmonary function test findings and might be useful for predicting the prognosis of patients with idiopathic pulmonary fibrosis (IPF). PURPOSE: To evaluate the association between the quantitative analysis of long-term follow-up CT of IPF and the progression and prognosis. MATERIAL AND METHODS: A total of 48 patients with IPF who received over one year of follow-up CT were included in this study. The results of quantitative analyses (emphysema, ground-glass attenuation [GGA], consolidation, reticulation, and honeycombing) using a CAD software program of initial and follow-up CT findings were evaluated, and the association with the progression of the total lesion of IPF and prognosis using Spearman's rank correlation and Cox regression analyses was considered. RESULTS: Results of quantitative analyses of consolidation, reticulation, honeycombing, and the total lesion on initial CT were correlated with progressive changes in the total lesion of IPF per year (r = 0.4375, 0.4128, 0.4649, and 0.4095, respectively). The results of quantitative analyses of honeycombing (hazard ratio [HR] = 1.40, 95% confidence interval [CI] = 1.03-1.89, P = 0.0314) and GGA (HR = 0.85, 95% CI = 0.72-0.99, P = 0.0384) at initial CT were prognostic factors according to a multivariate Cox regression analysis. CONCLUSION: The quantitative analysis of honeycombing using a CAD software program of CT findings may be useful for predicting the progression and prognosis of patients with IPF.