Investigation of the correlation between the change in the projected lung area and forced vital capacity using biphasic chest dynamic digital radiography: a cross-sectional study.

Chen, Q.; Ouyang, L.; Li, Q.; Xia, Z.; Li, X.; Liu, C.; Kim, SH.; Brunelli, A.; Lan, R.; Song, Y.

Investigation of the correlation between the change in the projected lung area and forced vital capacity using biphasic chest dynamic digital radiography: a cross-sectional study.

All Authors

Chen, Q.

Ouyang, L.

Li, Q.

Xia, Z.

Li, X.

Liu, C.

Kim, SH.

Brunelli, A.

Lan, R.

Song, Y.

LTHT Author

Brunelli, Alessandro

LTHT Department

Thoracic Surgery

Publication Date

2024

Item Type

Journal Article

Abstract

Background: Chest dynamic digital radiography (DDR) is used as a supplementary tool for the routine pulmonary function test (PFT); however, its potential as a novel standard PFT method has yet to be explored. Therefore, the present study aimed to investigate the correlation between the change in the projected lung area (DELTAPLA) and forced vital capacity (FVC) using chest DDR, and to establish a DDR-FVC estimation model and a predictive value model for the DELTAPLA. Methods: In total, 139 participants who underwent chest DDR and the PFT in the same period at The First Affiliated Hospital of Guangzhou Medical University from April 2022 to February 2023 were prospectively included in the study. The patients' age, gender, height, and weight measurements were recorded. Additionally, the DELTAPLA was measured, and the IWS workstation software was used for automated outlining and calculation. Subsequently, a correlation analysis and regression analysis models were employed to examine the relationship between the DELTAPLA, FVC, and individual physiological characteristics. Additionally, an independent sample t-test was used to determine whether there were any significant differences between the normal and abnormal FVC groups. Results: The 139 participants were grouped according to the results of the ratio of measured/predicted FVC values (FVC%pred); those with an FVC%pred >=80%, were allocated to the normal FVC group, and those with an FVC%pred <80% were allocated to the abnormal FVC group. The correlation coefficient was >0.8 in the full sample; the DELTAPLA showed a significant linear correlation with the measured FVC value [r=0.81, 95% confidence interval (CI): 0.75-0.86, P<0.001]. There was a significant difference in the DELTAPLA between the normal and abnormal FVC groups. With the DELTAPLA, age, gender, height, and weight as predictor variables, the following DDR-FVC estimation model was established: DDR-FVC estimation model = -0.997 + 1.35x10-4 x DELTAPLA + 0.017 x height - 0.014 x age + 0.249 x gender (1 for male and 0 for female) [adjusted R2 (adj. R2)=0.731, F=94.615, P<0.001]. The following formula was used to determine the predictive value of the DELTAPLA: Predictive value of DELTAPLA = -12,504.287 + 173.185 x height + 62.971 x weight - 84.933 x age (adj. R2=0.393, F=20.453, P<0.001). Conclusions: There was a linear correlation between the DELTAPLA measured by biphasic chest DDR and the FVC. A model for estimating the FVC was established based on the DELTAPLA, which allows the FVC to be assessed by the DELTAPLA measured by biphasic chest DDR. A predictive value model for the DELTAPLA was also established to provide DELTAPLA reference values for assessment and comparison.