Comparative analysis of the results of computed tomographic densitovolumetry during the stratification of patients with pulmonary sarcoidosis

Abstract

Aim. To assess the diagnostic significance of the indicators obtained by the new method of quantitative evaluation of digital data of computed tomography (CT) images of the chest (CT densitovolumetry) in groups of patients with a diagnosis of sarcoidosis, stratified by radiological patterns, in comparison with groups formed according to the classification principle of J.G.Scadding , as well as in comparison with functional pulmonary tests.Materials and methods. Healthy individuals (n=21) and patients with pulmonary sarcoidosis (n=101) were examined. Patients with sarcoidosis were divided into 5 groups according to the J.G.Scadding classification and into 5 groups according to combinations of radiological patterns. The lung function was assessed according to the data of forced expiratory spirometry, body plethysmography, and the study of diffusion capacity and lung volumes. All examined patients underwent a two-stage CT scan of the lungs in the inspiratory and expiratory phases with the measurement of parameters in 3 density ranges.Results. The values of the obtained quantitative indicators, determined by the new method of CT-densitovolumetry, differed from the control values in healthy individuals both in the general group of patients with sarcoidosis, and in separate groups according to the J.G.Scadding classification and groups divided by radiological patterns. As a result, an intergroup statistically significant difference in indicators was determined. Correlations were found between radiometric measurements and lung function variables.Conclusion. A new method of CT-densitovolumetry has identified a diagnostic difference between approaches to stratification of patients with pulmonary sarcoidosis. The results obtained can be treated as a useful tool for the development of a unified radiological classification based on qualitative CT characteristics of pathological changes in pulmonary sarcoidosis.