Expiratory CT in quantitative analysis of pulmonary vessels in COPD patients / 中国医学影像技术

ABSTRACT

Objective: To observe intrapulmonary vascular volume (IPVV) in chronic obstructive pulmonary disease (COPD) patients with double gas phase CT examination, so as to investigate the application value of expiratory phase CT in assessing pulmonary vascular alterations in COPD patients. Methods: Totally 89 patients with COPD were retrospectively collected who underwent double gas phase CT examination and pulmonary function test (PFT). Pearson or Spearman correlation test was used to analyze correlations of IPVV and PFT Results:, and Steiger's Z test was used to explore the differences of correlation coefficients. Results: In inspiratory scan, there was negative correlation between IPVV and forced expiratory volume in one second (FEV1)/forced vital capacity (FVC)in whole lung (WL)and all lobes (r=-0.22-0.36, P<0.05),and there was negative correlation between IPVV and FEV1% only at right middle lobe (RML) and left lower lobe (LLL)(r=-0.25, -0.23, both P<0.05).In expiratory scan, IPVV was negatively correlated with FEV1% (r=-0.20-0.36, P<0.05) and FEV1/FVC (r=-0.24-0.39, P<0.05). Changes of IPVV under respiratory state were positively correlated with FEV1% (r=0.31-0.46, P<0.01). Conclusion: Dual-gas phase CT can be used to quantitatively evaluate IPVV and changes of IPVV in COPD patients, while expiratory CT can provide more information for assessing degree of expiratory airflow obstruction in COPD, therefore providing a new approach for further observation of pulmonary vascular changes in COPD related pulmonary hypertension.