[Correlation between quantitative airway parameters and disease severity of coal workers' pneumoconiosis based on HRCT].

Objective: To observe the changes of small airway parameters in patients with coal workers' pneumoconiosis in different disease stages by high resolution computed tomography (HRCT) , and analyze the correlation between them and the severity of the disease. Methods: From June 2016 to June 2023, 25 healthy volunteers and 71 untreated patients with coal worker's pneumoconiosis in the Fifth People's Hospital of Ningxia were selected as the research objects. The clinical and imaging data of the patients were collected, and the disease stages were performed according to the dust exposure history and high-kilovolt chest X-ray. The patients were divided into 4 groups: control group (25 cases) , coal workers' pneumoconiosis stage Ⅰ group (17 cases) , coal workers' pneumoconiosis stage Ⅱ group (32 cases) and coal workers' pneumoconiosis stage Ⅲ group (22 cases) . Quantitative chest HRCT parameters of each group were collected, including the square root of wall area at 10 mm inner perimeter (AWT-Pi10, Pi10) , airway wall thickness, airway wall volume, airway wall area percentage of the whole lung and the 5th, 6th, 7th and 8th level airways, and low attenuation area percentage (LAA%) of the whole lung. Pulmonary function indicators were collected, including forced expiratory volume in 1 second (FEV(1)) and the percentage of its projected value [FEV(1) (%pred) ], the ratio of FEV(1) to forced vital capacity (FEV(1)/FVC) and the percentage of its projected value[FEV(1)/FVC (%pred) ]. One-way ANOVA or Kruskal-Wallis H test and Spearman rank correlation were used to analyze the difference and correlation. Results: Compared with control group, FEV(1), FEV(1) (%pred) , FEV(1)/FVC and FEV(1)/FVC (%pred) in stage Ⅱ and Ⅲ coal workers' pneumoconiosis groups were lower (P<0.05) . In addition, the FEV(1) and FEV(1) (%pred) of the stage Ⅲgroup were lower than those of the stageⅡ group (P<0.05) , and the FEV(1)/FVC and FEV(1)/FVC (%pred) of the stage Ⅲgroup were lower than those of the stage Ⅰgroup (P<0.05) . Compared with stage Ⅰ group, Pi10 in stage Ⅲ group were increased (P < 0.05) at the 6th and 8th level airways, and airway wall thickness and airway wall volume in the 6th, 7th and 8th level airways of stage Ⅲgroup increased (P<0.05) . Correlation analysis showed that all pulmonary function indexes were negatively correlated with Pi10 of whole lung and the 6th, 7th and 8th level airways (P<0.05) , all pulmonary function indexes were negatively correlated with airway wall thickness of the 7th and 8th level airways (P<0.05) , and FEV(1)/FVC (%pred) was negatively correlated with airway wall volume of the 7th and 8th level airways (P<0.05) . FEV(1), FEV(1) (%pred) , FEV(1)/FVC (%pred) were negatively correlated with percentage of airway wall area of whole lung and the 6th, 7th and 8th level airways (P<0.05) . Conclusion: The quantitative airway parameters of coal workers' pneumoconiosis based on HRCT are correlated with pulmonary function indexes, which can reflect the severity of coal workers' pneumoconiosis.