title: Comparison of CT-based Lobar Ventilation with 3He MR Imaging Ventilation Measurements.
abstract: OBJECTIVE
  To compare lobar lung ventilation computed from expiratory and inspiratory computed tomographic (CT) data with direct measurements of ventilation at hyperpolarized helium 3 ((3)He) magnetic resonance (MR) imaging by using same-breath hydrogen 1 ((1)H) MR imaging examinations to coregister the multimodality images.
  
  
  METHODS
  The study was approved by the national research ethics committee, and written patient consent was obtained. Thirty patients with asthma underwent breath-hold CT at total lung capacity and functional residual capacity. (3)He and (1)H MR images were acquired during the same breath hold at a lung volume of functional residual capacity plus 1 L. Lobar segmentations delineated by major fissures on both CT scans were used to calculate the percentage of ventilation per lobe from the change in inspiratory and expiratory lobar volumes. CT-based ventilation was compared with (3)He MR imaging ventilation by using diffeomorphic image registration of (1)H MR imaging to CT, which enabled indirect registration of (3)He MR imaging to CT. Statistical analysis was performed by using the Wilcoxon signed-rank test, Pearson correlation coefficient, and Bland-Altman analysis.
  
  
  RESULTS
  The mean ± standard deviation absolute difference between the CT and (3)He MR imaging percentage of ventilation volume in all lobes was 4.0% (right upper and right middle lobes, 5.4% ± 3.3; right lower lobe, 3.7% ± 3.9; left upper lobe, 2.8% ± 2.7; left lower lobe, 3.9% ± 2.6; Wilcoxon signed-rank test, P < .05). The Pearson correlation coefficient between the two techniques in all lobes was 0.65 (P < .001). Greater percentage of ventilation was seen in the upper lobes with (3)He MR imaging and in the lower lobes with CT. This was confirmed with Bland-Altman analysis, with 95% limits of agreement for right upper and middle lobes, -2.4, 12.7; right lower lobe, -11.7, 4.6; left upper lobe, -4.9, 8.7; and left lower lobe, -9.8, 2.8.
  
  
  CONCLUSIONS
  The percentage of regional ventilation per lobe calculated at CT was comparable to a direct measurement of lung ventilation at hyperpolarized (3)He MR imaging. This work provides evidence for the validity of the CT model, and same-breath (1)H MR imaging enables regional interpretation of (3)He ventilation MR imaging on the underlying lung anatomy at thin-section CT.
authors: From the Academic Units of Academic Radiology (B.A.T., A.J.S., F.C.H., H.M., J.C.K., J.P.R., J.M.W.) and Clinical Oncology (B.A.T., R.H.I.), University of Sheffield, C Floor, Royal Hallamshire Hospital, Glossop Road, Sheffield S10 2JF, England; Fluidda, Kontich, Belgium (C.V.H., J.D.B., W.V.); Institute for Lung Health, University of Leicester, Leicester, England (R.H., C.E.B.); Novartis, Basel, Switzerland (R.K.); and INSIGNEO Institute of In-silico Medicine, Sheffield, England (A.J.S., J.M.W.).
authors: Bilal A
authors: BA
authors: Tahir
authors: From the Academic Units of Academic Radiology (B.A.T., A.J.S., F.C.H., H.M., J.C.K., J.P.R., J.M.W.) and Clinical Oncology (B.A.T., R.H.I.), University of Sheffield, C Floor, Royal Hallamshire Hospital, Glossop Road, Sheffield S10 2JF, England; Fluidda, Kontich, Belgium (C.V.H., J.D.B., W.V.); Institute for Lung Health, University of Leicester, Leicester, England (R.H., C.E.B.); Novartis, Basel, Switzerland (R.K.); and INSIGNEO Institute of In-silico Medicine, Sheffield, England (A.J.S., J.M.W.).
authors: Cedric
authors: C
authors: Van Holsbeke
authors: From the Academic Units of Academic Radiology (B.A.T., A.J.S., F.C.H., H.M., J.C.K., J.P.R., J.M.W.) and Clinical Oncology (B.A.T., R.H.I.), University of Sheffield, C Floor, Royal Hallamshire Hospital, Glossop Road, Sheffield S10 2JF, England; Fluidda, Kontich, Belgium (C.V.H., J.D.B., W.V.); Institute for Lung Health, University of Leicester, Leicester, England (R.H., C.E.B.); Novartis, Basel, Switzerland (R.K.); and INSIGNEO Institute of In-silico Medicine, Sheffield, England (A.J.S., J.M.W.).
authors: Rob H
authors: RH
authors: Ireland
authors: From the Academic Units of Academic Radiology (B.A.T., A.J.S., F.C.H., H.M., J.C.K., J.P.R., J.M.W.) and Clinical Oncology (B.A.T., R.H.I.), University of Sheffield, C Floor, Royal Hallamshire Hospital, Glossop Road, Sheffield S10 2JF, England; Fluidda, Kontich, Belgium (C.V.H., J.D.B., W.V.); Institute for Lung Health, University of Leicester, Leicester, England (R.H., C.E.B.); Novartis, Basel, Switzerland (R.K.); and INSIGNEO Institute of In-silico Medicine, Sheffield, England (A.J.S., J.M.W.).
authors: Andrew J
authors: AJ
authors: Swift
authors: From the Academic Units of Academic Radiology (B.A.T., A.J.S., F.C.H., H.M., J.C.K., J.P.R., J.M.W.) and Clinical Oncology (B.A.T., R.H.I.), University of Sheffield, C Floor, Royal Hallamshire Hospital, Glossop Road, Sheffield S10 2JF, England; Fluidda, Kontich, Belgium (C.V.H., J.D.B., W.V.); Institute for Lung Health, University of Leicester, Leicester, England (R.H., C.E.B.); Novartis, Basel, Switzerland (R.K.); and INSIGNEO Institute of In-silico Medicine, Sheffield, England (A.J.S., J.M.W.).
authors: Felix C
authors: FC
authors: Horn
authors: From the Academic Units of Academic Radiology (B.A.T., A.J.S., F.C.H., H.M., J.C.K., J.P.R., J.M.W.) and Clinical Oncology (B.A.T., R.H.I.), University of Sheffield, C Floor, Royal Hallamshire Hospital, Glossop Road, Sheffield S10 2JF, England; Fluidda, Kontich, Belgium (C.V.H., J.D.B., W.V.); Institute for Lung Health, University of Leicester, Leicester, England (R.H., C.E.B.); Novartis, Basel, Switzerland (R.K.); and INSIGNEO Institute of In-silico Medicine, Sheffield, England (A.J.S., J.M.W.).
authors: Helen
authors: H
authors: Marshall
authors: From the Academic Units of Academic Radiology (B.A.T., A.J.S., F.C.H., H.M., J.C.K., J.P.R., J.M.W.) and Clinical Oncology (B.A.T., R.H.I.), University of Sheffield, C Floor, Royal Hallamshire Hospital, Glossop Road, Sheffield S10 2JF, England; Fluidda, Kontich, Belgium (C.V.H., J.D.B., W.V.); Institute for Lung Health, University of Leicester, Leicester, England (R.H., C.E.B.); Novartis, Basel, Switzerland (R.K.); and INSIGNEO Institute of In-silico Medicine, Sheffield, England (A.J.S., J.M.W.).
authors: John C
authors: JC
authors: Kenworthy
authors: From the Academic Units of Academic Radiology (B.A.T., A.J.S., F.C.H., H.M., J.C.K., J.P.R., J.M.W.) and Clinical Oncology (B.A.T., R.H.I.), University of Sheffield, C Floor, Royal Hallamshire Hospital, Glossop Road, Sheffield S10 2JF, England; Fluidda, Kontich, Belgium (C.V.H., J.D.B., W.V.); Institute for Lung Health, University of Leicester, Leicester, England (R.H., C.E.B.); Novartis, Basel, Switzerland (R.K.); and INSIGNEO Institute of In-silico Medicine, Sheffield, England (A.J.S., J.M.W.).
authors: Juan
authors: J
authors: Parra-Robles
authors: From the Academic Units of Academic Radiology (B.A.T., A.J.S., F.C.H., H.M., J.C.K., J.P.R., J.M.W.) and Clinical Oncology (B.A.T., R.H.I.), University of Sheffield, C Floor, Royal Hallamshire Hospital, Glossop Road, Sheffield S10 2JF, England; Fluidda, Kontich, Belgium (C.V.H., J.D.B., W.V.); Institute for Lung Health, University of Leicester, Leicester, England (R.H., C.E.B.); Novartis, Basel, Switzerland (R.K.); and INSIGNEO Institute of In-silico Medicine, Sheffield, England (A.J.S., J.M.W.).
authors: Ruth
authors: R
authors: Hartley
authors: From the Academic Units of Academic Radiology (B.A.T., A.J.S., F.C.H., H.M., J.C.K., J.P.R., J.M.W.) and Clinical Oncology (B.A.T., R.H.I.), University of Sheffield, C Floor, Royal Hallamshire Hospital, Glossop Road, Sheffield S10 2JF, England; Fluidda, Kontich, Belgium (C.V.H., J.D.B., W.V.); Institute for Lung Health, University of Leicester, Leicester, England (R.H., C.E.B.); Novartis, Basel, Switzerland (R.K.); and INSIGNEO Institute of In-silico Medicine, Sheffield, England (A.J.S., J.M.W.).
authors: Richard
authors: R
authors: Kay
authors: From the Academic Units of Academic Radiology (B.A.T., A.J.S., F.C.H., H.M., J.C.K., J.P.R., J.M.W.) and Clinical Oncology (B.A.T., R.H.I.), University of Sheffield, C Floor, Royal Hallamshire Hospital, Glossop Road, Sheffield S10 2JF, England; Fluidda, Kontich, Belgium (C.V.H., J.D.B., W.V.); Institute for Lung Health, University of Leicester, Leicester, England (R.H., C.E.B.); Novartis, Basel, Switzerland (R.K.); and INSIGNEO Institute of In-silico Medicine, Sheffield, England (A.J.S., J.M.W.).
authors: Chris E
authors: CE
authors: Brightling
authors: From the Academic Units of Academic Radiology (B.A.T., A.J.S., F.C.H., H.M., J.C.K., J.P.R., J.M.W.) and Clinical Oncology (B.A.T., R.H.I.), University of Sheffield, C Floor, Royal Hallamshire Hospital, Glossop Road, Sheffield S10 2JF, England; Fluidda, Kontich, Belgium (C.V.H., J.D.B., W.V.); Institute for Lung Health, University of Leicester, Leicester, England (R.H., C.E.B.); Novartis, Basel, Switzerland (R.K.); and INSIGNEO Institute of In-silico Medicine, Sheffield, England (A.J.S., J.M.W.).
authors: Jan
authors: J
authors: De Backer
authors: From the Academic Units of Academic Radiology (B.A.T., A.J.S., F.C.H., H.M., J.C.K., J.P.R., J.M.W.) and Clinical Oncology (B.A.T., R.H.I.), University of Sheffield, C Floor, Royal Hallamshire Hospital, Glossop Road, Sheffield S10 2JF, England; Fluidda, Kontich, Belgium (C.V.H., J.D.B., W.V.); Institute for Lung Health, University of Leicester, Leicester, England (R.H., C.E.B.); Novartis, Basel, Switzerland (R.K.); and INSIGNEO Institute of In-silico Medicine, Sheffield, England (A.J.S., J.M.W.).
authors: Wim
authors: W
authors: Vos
authors: From the Academic Units of Academic Radiology (B.A.T., A.J.S., F.C.H., H.M., J.C.K., J.P.R., J.M.W.) and Clinical Oncology (B.A.T., R.H.I.), University of Sheffield, C Floor, Royal Hallamshire Hospital, Glossop Road, Sheffield S10 2JF, England; Fluidda, Kontich, Belgium (C.V.H., J.D.B., W.V.); Institute for Lung Health, University of Leicester, Leicester, England (R.H., C.E.B.); Novartis, Basel, Switzerland (R.K.); and INSIGNEO Institute of In-silico Medicine, Sheffield, England (A.J.S., J.M.W.).
authors: Jim M
authors: JM
authors: Wild
mesh_terms: D000328:Adult; D000368:Aged; D001249:Asthma / Q000503:physiopathology*; D004802:Eosinophilia / Q000503:physiopathology*; D005260:Female; D006371:Helium; D006801:Humans; D008176:Lung Volume Measurements; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012129:Respiratory Function Tests; D013183:Sputum / Q000166:cytology; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D006371:Helium