title: Vibration response imaging in healthy Japanese subjects.
abstract: BACKGROUND
  Vibration response imaging (VRI) records the intensity and distribution of lung sounds during the respiration cycle. Our objective was to analyze VRI findings in healthy Japanese adults.
  
  
  METHODS
  VRI images of 106 healthy subjects (33.7±9.6 years, 52 male and 54 female), including 67 nonsmokers and 39 asymptomatic smokers, were recorded. The regional intensity of vibrations was assessed using quantitative lung data (QLD), and VRI dynamic images by rater assessment, left and right lung asynchrony (gap index), and regional lung asynchrony (asynchrony score).
  
  
  RESULTS
  A dominance of total left lung QLD was observed in all subjects, and this phenomenon was more prominent in female subjects. However, there was no significant difference between the total left and total right lung QLD in smokers. Rater assessments showed that 81.1% of all subjects had a normal final assessment. Male subjects had a significantly higher percentage of good or normal assessments for all image scores, except dynamic image scoring. The asynchrony score was significantly higher in female subjects. There were no significant differences in these qualitative assessments between non-smokers and smokers.
  
  
  CONCLUSIONS
  Although our QLD results were similar to those of a previous report, there were discrepancies between sexes for the qualitative assessments. A significantly higher number of female subjects had abnormal images as assessed by the raters. Furthermore, significantly higher asynchrony scores were observed in female subjects. The VRI variability in sex may be considered normal among the Japanese population. This study is registered with UMIN-CTR under registration number UMIN000002355.
authors.affiliation: Division of Respiratory and Infectious Diseases, Department of Internal Medicine, St. Marianna University School of Medicine, Kawasaki, Japan. Electronic address: m-mine@marianna-u.ac.jp.
authors.forename: Masamichi
authors.initials: M
authors.lastname: Mineshita
authors.affiliation: Division of Respiratory and Infectious Diseases, Department of Internal Medicine, St. Marianna University School of Medicine, Kawasaki, Japan. Electronic address: shirakawa@vega.ocn.ne.jp.
authors.forename: Taeko
authors.initials: T
authors.lastname: Shirakawa
authors.affiliation: Division of Respiratory and Infectious Diseases, Department of Internal Medicine, St. Marianna University School of Medicine, Kawasaki, Japan. Electronic address: junko@qa2.so-net.ne.jp.
authors.forename: Junko
authors.initials: J
authors.lastname: Saji
authors.affiliation: Division of Respiratory and Infectious Diseases, Department of Internal Medicine, St. Marianna University School of Medicine, Kawasaki, Japan. Electronic address: hiroshihstv@yahoo.co.jp.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Handa
authors.affiliation: Division of Respiratory and Infectious Diseases, Department of Internal Medicine, St. Marianna University School of Medicine, Kawasaki, Japan. Electronic address: n2furuya@marianna-u.ac.jp.
authors.forename: Naoki
authors.initials: N
authors.lastname: Furuya
authors.affiliation: Division of Respiratory and Infectious Diseases, Department of Internal Medicine, St. Marianna University School of Medicine, Kawasaki, Japan. Electronic address: h2kida@marianna-u.ac.jp.
authors.forename: Hirotaka
authors.initials: H
authors.lastname: Kida
authors.affiliation: Division of Respiratory and Infectious Diseases, Department of Internal Medicine, St. Marianna University School of Medicine, Kawasaki, Japan. Electronic address: hirokinishine@hotmail.co.jp.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Nishine
authors.affiliation: Division of Respiratory and Infectious Diseases, Department of Internal Medicine, St. Marianna University School of Medicine, Kawasaki, Japan. Electronic address: nobuyama@marianna-u.ac.jp.
authors.forename: Seiichi
authors.initials: S
authors.lastname: Nobuyama
authors.affiliation: Division of Respiratory and Infectious Diseases, Department of Internal Medicine, St. Marianna University School of Medicine, Kawasaki, Japan. Electronic address: t2inoue@marianna-u.ac.jp.
authors.forename: Takeo
authors.initials: T
authors.lastname: Inoue
authors.affiliation: Division of Respiratory and Infectious Diseases, Department of Internal Medicine, St. Marianna University School of Medicine, Kawasaki, Japan. Electronic address: miyazawat@marianna-u.ac.jp.
authors.forename: Teruomi
authors.initials: T
authors.lastname: Miyazawa
mesh_terms: D000162:Acoustics / Q000295:instrumentation*; D000328:Adult; D044466:Asian People; D001314:Auscultation / Q000295:instrumentation* / Q000379:methods*; D003952:Diagnostic Imaging / Q000295:instrumentation* / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D014732:Vibration; D055815:Young Adult
keywords: Breath sounds; Healthy subjects; Lung function; Vibration response imaging