• CALIPER
• HRCT
• idiopathic pulmonary fibrosis
• IPF
• prognosis
• progression
• visual score

Aims: Idiopathic Pulmonary Fibrosis (IPF) has an unpredictable course and a staging system is still missing. We evaluated the role of radiological markers obtained with visual score and automatic quantitative analysis in predicting prognosis, clinical decline and progression in treated patients.
Materials and methods: we retrospectively selected 38 IPF patients with a baseline HRCT and pulmonary function tests (PFTs) available. HRCTs were evaluated by two radiologists using semi-quantitative visual score and automatic software (CALIPER).
Lung involvement was expressed as fibrosis score (FS) using visual score, and as interstitial lung disease score (ILD) and pulmonary vascular-related structure (PVRS) with CALIPER.
We evaluated radiological threshold predictive of 3-years mortality and short-term clinical decline. We analyzed clinical and radiological progression in 24 patients with serial CTs.
Results: Mortality rate was higher in patients with lower baseline values of FVC and DLCO (p = 0.012 and p = 0.004) and with higher baseline values of PVRS (p = 0.0001), ILD (p = 0.023) and FS (p = 0.016). Patients with PVRS ≥ 5%, ILD ≥ 18% and FS ≥ 30% had worse prognosis and more hospitalizations.
During follow-up, despite no significant decline of FVC, radiological markers showed significant progression (PVRS, p = 0.002; ILD, p = 0.011; FS, p = 0.003). Clinical and radiological progressions had significant correlations, the strongest between ILD and PVRS (p = < 0.0001, r = 0.762).
Conclusion: IPF radiological markers are very promising tools to determine prognosis and progression in treated patients. They also specifically underlined subclinical disease progression.