title: Quantification of Lung PET Images: Challenges and Opportunities.
abstract: Millions of people are affected by respiratory diseases, leading to a significant health burden globally. Because of the current insufficient knowledge of the underlying mechanisms that lead to the development and progression of respiratory diseases, treatment options remain limited. To overcome this limitation and understand the associated molecular changes, noninvasive imaging techniques such as PET and SPECT have been explored for biomarker development, with18F-FDG PET imaging being the most studied. The quantification of pulmonary molecular imaging data remains challenging because of variations in tissue, air, blood, and water fractions within the lungs. The proportions of these components further differ depending on the lung disease. Therefore, different quantification approaches have been proposed to address these variabilities. However, no standardized approach has been developed to date. This article reviews the data evaluating18F-FDG PET quantification approaches in lung diseases, focusing on methods to account for variations in lung components and the interpretation of the derived parameters. The diseases reviewed include acute respiratory distress syndrome, chronic obstructive pulmonary disease, and interstitial lung diseases such as idiopathic pulmonary fibrosis. Based on review of prior literature, ongoing research, and discussions among the authors, suggested considerations are presented to assist with the interpretation of the derived parameters from these approaches and the design of future studies.
authors.affiliation: Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri chend@wustl.edu.
authors.forename: Delphine L
authors.initials: DL
authors.lastname: Chen
authors.affiliation: Department of Medicine, University of Cambridge, Cambridge, United Kingdom.|Cambridge University Hospitals NHS Foundation Trust, Cambridge, United Kingdom.
authors.forename: Joseph
authors.initials: J
authors.lastname: Cheriyan
authors.affiliation: Department of Medicine, University of Cambridge, Cambridge, United Kingdom.
authors.forename: Edwin R
authors.initials: ER
authors.lastname: Chilvers
authors.affiliation: Queen's Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom.
authors.forename: Gourab
authors.initials: G
authors.lastname: Choudhury
authors.affiliation: Imanova Ltd., London, United Kingdom.
authors.forename: Christopher
authors.initials: C
authors.lastname: Coello
authors.affiliation: Queen's Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom.
authors.forename: Martin
authors.initials: M
authors.lastname: Connell
authors.affiliation: Department of Medicine, University of Cambridge, Cambridge, United Kingdom.
authors.forename: Marie
authors.initials: M
authors.lastname: Fisk
authors.affiliation: Institute of Nuclear Medicine, University College London, London, United Kingdom.
authors.forename: Ashley M
authors.initials: AM
authors.lastname: Groves
authors.affiliation: Imanova Ltd., London, United Kingdom.|Department of Medicine, Imperial College London, London, United Kingdom.
authors.forename: Roger N
authors.initials: RN
authors.lastname: Gunn
authors.affiliation: Institute of Nuclear Medicine, University College London, London, United Kingdom.
authors.forename: Beverley F
authors.initials: BF
authors.lastname: Holman
authors.affiliation: Institute of Nuclear Medicine, University College London, London, United Kingdom.
authors.forename: Brian F
authors.initials: BF
authors.lastname: Hutton
authors.affiliation: Medical Image Analysis Consultant, London, United Kingdom.
authors.forename: Sarah
authors.initials: S
authors.lastname: Lee
authors.affiliation: Queen's Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom.
authors.forename: William
authors.initials: W
authors.lastname: MacNee
authors.affiliation: Clinical Discovery, Respiratory Therapy Area Unit, GlaxoSmithKline R&D, King of Prussia, Pennsylvania.
authors.forename: Divya
authors.initials: D
authors.lastname: Mohan
authors.affiliation: University Hospitals Coventry and Warwickshire, Coventry, United Kingdom.
authors.forename: David
authors.initials: D
authors.lastname: Parr
authors.affiliation: Derby Teaching Hospitals NHS Foundation Trust, Derby, United Kingdom.
authors.forename: Deepak
authors.initials: D
authors.lastname: Subramanian
authors.affiliation: Clinical Discovery, Respiratory Therapy Area Unit, GlaxoSmithKline R&D, King of Prussia, Pennsylvania.
authors.forename: Ruth
authors.initials: R
authors.lastname: Tal-Singer
authors.affiliation: Institute of Nuclear Medicine, University College London, London, United Kingdom.
authors.forename: Kris
authors.initials: K
authors.lastname: Thielemans
authors.affiliation: Queen's Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom.
authors.forename: Edwin J R
authors.initials: EJ
authors.lastname: van Beek
authors.affiliation: Department of Medicine, University of Cambridge, Cambridge, United Kingdom.
authors.forename: Laurence
authors.initials: L
authors.lastname: Vass
authors.affiliation: Worldwide Research and Development, Pfizer, Inc., Cambridge, Massachusetts; and.
authors.forename: Jeremy W
authors.initials: JW
authors.lastname: Wellen
authors.affiliation: Department of Medicine, University of Cambridge, Cambridge, United Kingdom.|Cambridge University Hospitals NHS Foundation Trust, Cambridge, United Kingdom.
authors.forename: Ian
authors.initials: I
authors.lastname: Wilkinson
authors.affiliation: Experimental Medicine Imaging, GlaxoSmithKline, Stevenage, United Kingdom.
authors.forename: Frederick J
authors.initials: FJ
authors.lastname: Wilson
mesh_terms: D019788:Fluorodeoxyglucose F18; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008168:Lung / Q000000981:diagnostic imaging*; D008171:Lung Diseases / Q000000981:diagnostic imaging*; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012129:Respiratory Function Tests / Q000379:methods*; D012680:Sensitivity and Specificity
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18
keywords: lung inflammation; molecular imaging; positron emission tomography; pulmonary