title: Assessment of regional lung function with multivolume (1)H MR imaging in health and obstructive lung disease: comparison with (3)He MR imaging.
abstract: OBJECTIVE
  To introduce a method based on multivolume proton (hydrogen [(1)H]) magnetic resonance (MR) imaging for the regional assessment of lung ventilatory function, investigating its use in healthy volunteers and patients with obstructive lung disease and comparing the outcome with the outcome of the research standard helium 3 ((3)He) MR imaging.
  
  
  METHODS
  The institutional review board approved the HIPAA-compliant protocol, and informed written consent was obtained from each subject. Twenty-six subjects, including healthy volunteers (n = 6) and patients with severe asthma (n = 11) and mild (n = 6) and severe (n = 3) emphysema, were imaged with a 1.5-T whole-body MR unit at four lung volumes (residual volume [ RV residual volume ], functional residual capacity [ FRC functional residual capacity ], 1 L above FRC functional residual capacity [ FRC+1 L 1 L above FRC ], total lung capacity [ TLC total lung capacity ]) with breath holds of 10-11 seconds, by using volumetric interpolated breath-hold examination. Each pair of volumes were registered, resulting in maps of (1)H signal change between the two lung volumes. (3)He MR imaging was performed at FRC+1 L 1 L above FRC by using a two-dimensional gradient-echo sequence. (1)H signal change and (3)He signal were measured and compared in corresponding regions of interest selected in ventral, intermediate, and dorsal areas.
  
  
  RESULTS
  In all volunteers and patients combined, proton signal difference between TLC total lung capacity and RV residual volume correlated positively with (3)He signal (correlation coefficient R(2) = 0.64, P < .001). Lower (P < .001) but positive correlation results from (1)H signal difference between FRC functional residual capacity and FRC+1 L 1 L above FRC (R(2) = 0.44, P < .001). In healthy volunteers, (1)H signal changes show a higher median and interquartile range compared with patients with obstructive disease and significant differences between nondependent and dependent regions.
  
  
  CONCLUSIONS
  Findings in this study demonstrate that multivolume (1)H MR imaging, without contrast material, can be used as a biomarker for regional ventilation, both in healthy volunteers and patients with obstructive lung disease.
authors.affiliation: From the Department of Electronics, Information, and Bioengineering, Politecnico di Milano, Piazza L. da Vinci 32, 20133 Milan, Italy (F.P., A.A.); Mallinckrodt Institute of Radiology (J.D.Q., D.A.Y.), Department of Internal Medicine (M.C.), and Department of Physics (J.C.W.), Washington University School of Medicine, St Louis, Mo; and Center for Pulmonary Imaging Research, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio (J.C.W.).
authors.forename: Francesca
authors.initials: F
authors.lastname: Pennati
authors.forename: James D
authors.initials: JD
authors.lastname: Quirk
authors.forename: Dmitriy A
authors.initials: DA
authors.lastname: Yablonskiy
authors.forename: Mario
authors.initials: M
authors.lastname: Castro
authors.forename: Andrea
authors.initials: A
authors.lastname: Aliverti
authors.forename: Jason C
authors.initials: JC
authors.lastname: Woods
mesh_terms: D000328:Adult; D000368:Aged; D001249:Asthma / Q000503:physiopathology*; D016022:Case-Control Studies; D005260:Female; D006371:Helium; D006801:Humans; D006859:Hydrogen; D008176:Lung Volume Measurements; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D029424:Pulmonary Disease, Chronic Obstructive / Q000503:physiopathology*; D011656:Pulmonary Emphysema / Q000503:physiopathology*; D012129:Respiratory Function Tests
chemical_list: D006371:Helium; D006859:Hydrogen