title: Detection of abnormalities in dyspneic patients using a new lung imaging modality.
abstract: BACKGROUND
  Although chest radiography is a useful examination tool, it has limitations. Because not all chest conditions can be detected on a radiograph, radiography cannot necessarily rule out all irregularities in the chest. Therefore, further imaging studies may be required to clarify the results of a chest radiograph, or to identify abnormalities that are not readily visible. The aim of this study was to compare traditional chest radiography with acoustic-based imaging (vibration response imaging) for the detection of lung abnormalities in patients with acute dyspnea.
  
  
  METHODS
  The current investigation was a pilot study. Respiratory sounds throughout the respiratory cycle were captured using an acoustic-based imaging technique. Consecutive patients who presented to the emergency department with acute dyspnea and a normal chest radiograph on admission were enrolled and underwent imaging at the time of presentation. Dynamic and static images of vibration (breath sounds) and a dynamic image score were generated, and assessments were made using an evaluation form.
  
  
  RESULTS
  In healthy volunteer controls (n = 61), the mean dynamic image score was 6.3 ± 1.9. In dyspneic patients with normal chest radiographs (n = 51) and abnormal chest radiographs (n = 48), the dynamic image scores were 4.7 ± 2.7 and 5.1 ± 2.5, respectively (P < 0.05). The final assessment of the vibration images indicated abnormal findings in 15%, 86% and 90% of the participants in the above groups, respectively (P < 0.05).
  
  
  CONCLUSIONS
  In patients with acute dyspnea who present with normal chest radiographs, respiratory sound analyses often showed abnormal values. Hence, the ability of acoustic-based recordings to offer objective and noninvasive measurements of abnormal sound transmission may be useful in the clinical setting for patients presenting with acute dyspnea.
authors.affiliation: Department of Emergency Medicine, Beijing Shijitan Hospital Capital Medical University, Beijing 100038, China. Email: wangzhen1369@hotmail.com.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Department of Emergency Medicine, Beijing Shijitan Hospital Capital Medical University, Beijing 100038, China.
authors.forename: Yingxia
authors.initials: Y
authors.lastname: Xiong
mesh_terms: D000328:Adult; D004417:Dyspnea / Q000503:physiopathology*; D004636:Emergency Service, Hospital; D005260:Female; D006801:Humans; D008168:Lung / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D012135:Respiratory Sounds / Q000503:physiopathology*