CT quantitative analysis and visual scores of pulmonary alveolar proteinosis and correlation with pulmonary function

Objective: To investigate the evaluating the value of CT quantitative analysis and visual scores on pulmonary alveolar proteinosis (PAP). Methods: Thirty one patients with PAP who underwent chest HRCT scans and pulmonary function tests (PFTs) between July 2014 and April 2016 in our hospital were collected and analyzed. HRCT mean lung density (MLD) was measured by syngo In Space Lung Parenchyma Analysis. Using CT visual scores (HRCT score and RE score), two radiologists with three-years experience at least evaluated pulmonary lesions retrospectively. SPSS 21.0 statistical software was used to analyze the data. Spearman correlation analysis was used to evaluate the correlation between MLD, HRCT score and RE score. The correlation between MLD, HRCT score, RE score, the parameters of PFTs, and blood gas parameters were also analyzed by Spearman correlation analysis. Results: There were correlations between MLD, HRCT score and RE score. The correlation coefficient among MLD, HRCT score and RE score were r = 0.835 vs r = 0.768 vs r = 0.838 in baseline. The correlation coefficient among MLD, HRCT score and RE score were r = 0.827 vs r = 0.780 vs r = 0.896 in follow-up. And there were also strong correlation between ΔMLD, ΔHRCT_score and ΔRE_score. The correlation coefficient among ΔMLD, ΔHRCT_score and ΔRE_score were r = 0.599 vs r = 0.651 vs r = 0.867. There were significantly (P < 0.05) negative correlations among MLD, HRCT score, RE score and VA, D_LCO in baseline and follow-up retrospectively. There were significantly (P ≤ 0.001) negative correlations among the ΔMLD, ΔHRCT_score, ΔRE_score and ΔVA, ΔD_LCO. The correlation among MLD, HRCT score, RE score and D_LCO was more significant than that of VA. The correlation among ΔMLD, ΔHRCT_score, ΔRE_score and ΔD_LCO was more significant than that of ΔVA. There were markedly (P < 0.05) negative correlations between MLD and PO₂, and the correlation coefficient were r = -0.738 in baseline vs r = -0.810 in follow-up. Conclusion: The HRCT quantitative analysis and HRCT visual scores are feasible to evaluate PAP. (authors)