title: Combined helium-3/proton magnetic resonance imaging measurement of ventilated lung volumes in smokers compared to never-smokers.
abstract: OBJECTIVE
  To use a combination of helium-3 (3-He) magnetic resonance imaging (MRI) and proton single-shot fast spin echo (SSFSE) to compare ventilated lung volumes in groups of "healthy" smokers, smokers diagnosed with moderate chronic obstructive pulmonary disease (COPD), and never-smokers.
  
  
  METHODS
  All study participants were assessed with spirometry prior to imaging. 3-He images were collected during an arrested breath hold, after inhaling a mixture of 200 mL of hyperpolarized 3-He/800 mL of N2. Proton SSFSE images were acquired after inhaling 1 liter of room air. The ventilated volume for each study participant was calculated from the 3-He images, and a ratio was calculated to give a percentage ventilated lung volume.
  
  
  RESULTS
  Never-smokers exhibited a 90% mean ventilated volume. The mean ventilated lung volumes for healthy smokers and smokers diagnosed with COPD were 75.2% and 67.6%, respectively. No correlation with spirometry was demonstrated for either of the smoking groups.
  
  
  CONCLUSIONS
  Combined 3-He/Proton SSFSE MRI of the lungs is a noninvasive method, using nonionizing radiation, which demonstrates ventilated airspaces and enables the calculation of ventilated lung volumes. This method appears to be sensitive to early obstructive changes in the lungs of smokers.
authors.affiliation: Unit Academic of Radiology, University of Sheffield, Royal Hallamshire Hospital, Sheffield, UK. n.woodhouse@sheffield.ac.uk
authors.forename: Neil
authors.initials: N
authors.lastname: Woodhouse
authors.forename: Jim M
authors.initials: JM
authors.lastname: Wild
authors.forename: Martyn N J
authors.initials: MN
authors.lastname: Paley
authors.forename: Stanislao
authors.initials: S
authors.lastname: Fichele
authors.forename: Zead
authors.initials: Z
authors.lastname: Said
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Swift
authors.forename: Edwin J R
authors.initials: EJ
authors.lastname: van Beek
mesh_terms: D000328:Adult; D005260:Female; D006371:Helium; D006801:Humans; D007554:Isotopes; D008176:Lung Volume Measurements / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D029424:Pulmonary Disease, Chronic Obstructive / Q000503:physiopathology; D012143:Respiratory Physiological Phenomena; D012907:Smoking / Q000503:physiopathology*
chemical_list: D007554:Isotopes; D006371:Helium