title: Clinical utility of computed tomographic lung volumes in patients with chronic obstructive pulmonary disease.
abstract: BACKGROUND
  Published data concerning the utility of computed tomography (CT)-based lung volumes are limited to correlation with lung function.
  
  
  OBJECTIVE
  The aim of this study was to evaluate the clinical utility of the CT expiratory-to-inspiratory lung volume ratio (CT Vratio) by assessing the relationship with clinically relevant outcomes.
  
  
  METHODS
  A total of 75 stable chronic obstructive pulmonary disease (COPD) patients having pulmonary function testing and volumetric CT at full inspiration and expiration were retrospectively evaluated. Inspiratory and expiratory CT lung volumes were measured using in-house software. Correlation of the CT Vratio with patient-centered outcomes, including the modified Medical Research Council (MMRC) dyspnea score, the 6-min walk distance (6MWD), the St. George's Respiratory Questionnaire (SGRQ) score, and multidimensional COPD severity indices, such as the BMI, airflow obstruction, dyspnea, and exercise capacity index (BODE) and age, dyspnea, and airflow obstruction (ADO), were analyzed.
  
  
  RESULTS
  The CT Vratio correlated significantly with BMI (r = -0.528, p < 0.001). The CT Vratio was also significantly associated with MMRC dyspnea (r = 0.387, p = 0.001), 6MWD (r = -0.459, p < 0.001), and SGRQ (r = 0.369, p = 0.001) scores. Finally, the CT Vratio had significant correlations with the BODE and ADO multidimensional COPD severity indices (r = 0.605, p < 0.001; r = 0.411, p < 0.001).
  
  
  CONCLUSIONS
  The CT Vratio had significant correlations with patient-centered outcomes and multidimensional COPD severity indices.
authors: Department of Pulmonary and Critical Care Medicine, Asthma Center and Clinical Research Center for Chronic Obstructive Airway Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors: Jae Seung
authors: JS
authors: Lee
authors: Sang-Min
authors: SM
authors: Lee
authors: Joon Beom
authors: JB
authors: Seo
authors: Sei Won
authors: SW
authors: Lee
authors: Jin Won
authors: JW
authors: Huh
authors: Yeon-Mok
authors: YM
authors: Oh
authors: Sang-Do
authors: SD
authors: Lee
mesh_terms: D000368:Aged; D015331:Cohort Studies; D004417:Dyspnea / Q000209:etiology / Q000503:physiopathology; D005080:Exercise Test; D017079:Exercise Tolerance; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008176:Lung Volume Measurements; D008297:Male; D008875:Middle Aged; D029424:Pulmonary Disease, Chronic Obstructive / Q000150:complications / Q000000981:diagnostic imaging* / Q000503:physiopathology; D012129:Respiratory Function Tests; D012189:Retrospective Studies; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed