title: Estimation of gas and tissue lung volumes by MRI: functional approach of lung imaging.
abstract: OBJECTIVE
  The purpose of this work was to assess the accuracy of MRI for the determination of lung gas and tissue volumes.
  
  
  METHODS
  Fifteen healthy subjects underwent MRI of the thorax and pulmonary function tests [vital capacity (VC) and total lung capacity (TLC)] in the supine position. MR examinations were performed at inspiration and expiration. Lung volumes were measured by a previously validated technique on phantoms. Both individual and total lung volumes and capacities were calculated. MRI total vital capacity (VC(MRI)) was compared with spirometric vital capacity (VC(SP)). Capacities were correlated to lung volumes. Tissue volume (V(T)) was estimated as the difference between the total lung volume at full inspiration and the TLC.
  
  
  RESULTS
  No significant difference was seen between VC(MRI) and VC(SP). Individual capacities were well correlated (r = 0.9) to static volume at full inspiration. The V(T) was estimated to be 836+/-393 ml.
  
  
  CONCLUSIONS
  This preliminary study demonstrates that MRI can accurately estimate lung gas and tissue volumes. The proposed approach appears well suited for functional imaging of the lung.
authors.affiliation: Department of Radiology, University René Descartes-Paris V, Ambroise Paré Hospital, Boulogne, France.
authors.forename: S D
authors.initials: SD
authors.lastname: Qanadli
authors.forename: E
authors.initials: E
authors.lastname: Orvoen-Frija
authors.forename: P
authors.initials: P
authors.lastname: Lacombe
authors.forename: R
authors.initials: R
authors.lastname: Di Paola
authors.forename: J
authors.initials: J
authors.lastname: Bittoun
authors.forename: G
authors.initials: G
authors.lastname: Frija
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D016014:Linear Models; D008168:Lung / Q000033:anatomy & histology* / Q000502:physiology; D008176:Lung Volume Measurements / Q000295:instrumentation / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000295:instrumentation / Q000379:methods* / Q000706:statistics & numerical data; D008297:Male; D019047:Phantoms, Imaging / Q000706:statistics & numerical data; D012016:Reference Values; D018709:Statistics, Nonparametric