The value of high-resolution CT visual scoring and quantitative analysis for the assessment of pulmonary Langerhans cell histiocytosis in adults / 中华放射学杂志

ABSTRACT

Objective:To explore the value of high-resolution CT (HRCT) visual scores and quantitative analysis in assessing pulmonary Langerhans cell histiocytosis (PLCH) in adults.Methods:In total 51 adult patients with PLCH confirmed by pathology in Peking Union Medical College Hospital from August 2014 to December 2021 were retrospectively analyzed. All patients underwent HRCT and pulmonary function tests (PFT). The involvement of the nodular and cystic lesions were evaluated by two experienced radiologists using CT visual scores. The cases were divided into three groups based on the nodular scores, and into four groups based on the cystic scores, respectively. Ratio of low attenuation areas (LAA%) was measured by an automatic post-processing software. Pulmonary function indices including forced expiratory volume in the first second (FEV 1), forced vital capacity (FVC), FEV 1/FVC, diffusion capacity for carbon monoxide of lung (D LCO), alveolar ventilation (V A), D LCO/V A, D LCO corrected for hemoglobin (D LCOc), D LCOc/V A were collected. FEV 1/FVC was expressed as measured values and other indices were expressed as percent predicted (%pred). Spearman correlation analysis was used to evaluate the correlation between HRCT visual scores, LAA% and PFT. The lung function indices among different nodular groups as well as among different cystic groups were compared using the Kruskal‐Wallis test. Results:Both nodular and cystic lesions were found on HRCT images of all 51 patients. There were no correlation between the visual scores of nodular lesions and lung function indices (all P>0.05). There were no significant differences in lung function indices among different nodular groups (all P>0.05). The visual scores of cystic lesions were negatively correlated with FEV 1/FVC, D LCO%pred, D LCO/V A%pred, D LCOc%pred, D LCOc/V A%pred ( r=-0.491, -0.347, -0.330, -0.373, -0.346, respectively, all P<0.05); the pulmonary function indices among different cystic groups had significant difference (all P<0.05). LAA% were negatively correlated with FEV 1/FVC, D LCO%pred, D LCO/V A%pred, D LCOc%pred, D LCOc/V A%pred ( r=-0.278, -0.378, -0.418, -0.395, -0.451, respectively, all P<0.05). Conclusion:HRCT visual scores of nodular lesions do not correlate with lung function in patients with PLCH. Visual scores and quantitative analysis of the cystic lesions can reflect the impairment degree of pulmonary ventilation and diffusion function to a certain extent, and may be used in assessment of patients with PLCH.