title: Inter- and Intraobserver Agreement of18F-FDG PET/CT Image Interpretation in Patients Referred for Assessment of Cardiac Sarcoidosis.
abstract: Recent studies have reported the usefulness of18F-FDG PET in aiding with the diagnosis and management of patients with cardiac sarcoidosis (CS). However, image interpretation of18F-FDG PET for CS is sometimes challenging. We sought to investigate the inter- and intraobserver agreement and explore factors that led to important discrepancies between readers.Methods:We studied consecutive patients with no significant coronary artery disease who were referred for assessment of CS. Two experienced readers masked to clinical information, imaging reports, independently reviewed18F-FDG PET/CT images.18F-FDG PET/CT images were interpreted according to a predefined standard operating procedure, with cardiac18F-FDG uptake patterns categorized into 5 patterns: none, focal, focal on diffuse, diffuse, and isolated lateral wall or basal uptake. Overall image assessment was classified as either consistent with active CS or not.Results:One hundred scans were included from 71 patients. Of these, 46 underwent18F-FDG PET/CT with a no-restriction diet (no-restriction group), and 54 underwent18F-FDG PET/CT with a low-carbohydrate, high-fat and protein-permitted diet (low-carb group). There was agreement of the interpretation category in 74 of 100 scans. The κ-value of agreement among all 5 categories was 0.64, indicating moderate agreement. For overall clinical interpretation, there was agreement in 93 of 100 scans (κ = 0.85). When scans were divided into the preparation groups, there was a trend toward higher agreement in the low-carb group versus the no-restriction group (80% vs. 67%,P= 0.08). Regarding the overall clinical interpretation, there was also a trend toward greater agreement in the low-carb group versus the no-restriction group (96% vs. 89%,P= 0.08).Conclusion: The interobserver agreement of cardiac18F-FDG uptake image patterns was moderate. However, agreement was better regarding overall interpretation of CS. Detailed prescan dietary preparation seemed to improve interobserver agreement.
authors.affiliation: Molecular Function and Imaging Program, the National Cardiac PET Centre and the Arrhythmia Service, Division of Cardiology, Department of Medicine, University of Ottawa Heart Institute, Ottawa, Canada.|First Department of Medicine, Hokkaido University School of Medicine, Sapporo, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ohira
authors.affiliation: Molecular Function and Imaging Program, the National Cardiac PET Centre and the Arrhythmia Service, Division of Cardiology, Department of Medicine, University of Ottawa Heart Institute, Ottawa, Canada.
authors.forename: Brian Mc
authors.initials: BM
authors.lastname: Ardle
authors.affiliation: Molecular Function and Imaging Program, the National Cardiac PET Centre and the Arrhythmia Service, Division of Cardiology, Department of Medicine, University of Ottawa Heart Institute, Ottawa, Canada.
authors.forename: Robert A
authors.initials: RA
authors.lastname: deKemp
authors.affiliation: Molecular Function and Imaging Program, the National Cardiac PET Centre and the Arrhythmia Service, Division of Cardiology, Department of Medicine, University of Ottawa Heart Institute, Ottawa, Canada.
authors.forename: Pablo
authors.initials: P
authors.lastname: Nery
authors.affiliation: Molecular Function and Imaging Program, the National Cardiac PET Centre and the Arrhythmia Service, Division of Cardiology, Department of Medicine, University of Ottawa Heart Institute, Ottawa, Canada.|Centre Hospitalier de l'Université de Montréal (CHUM), Montréal, Québec, Canada; and.
authors.forename: Daniel
authors.initials: D
authors.lastname: Juneau
authors.affiliation: Molecular Function and Imaging Program, the National Cardiac PET Centre and the Arrhythmia Service, Division of Cardiology, Department of Medicine, University of Ottawa Heart Institute, Ottawa, Canada.
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Renaud
authors.affiliation: Molecular Function and Imaging Program, the National Cardiac PET Centre and the Arrhythmia Service, Division of Cardiology, Department of Medicine, University of Ottawa Heart Institute, Ottawa, Canada.
authors.forename: Ran
authors.initials: R
authors.lastname: Klein
authors.affiliation: Molecular Function and Imaging Program, the National Cardiac PET Centre and the Arrhythmia Service, Division of Cardiology, Department of Medicine, University of Ottawa Heart Institute, Ottawa, Canada.
authors.forename: Owen
authors.initials: O
authors.lastname: Clarkin
authors.affiliation: Molecular Function and Imaging Program, the National Cardiac PET Centre and the Arrhythmia Service, Division of Cardiology, Department of Medicine, University of Ottawa Heart Institute, Ottawa, Canada.
authors.forename: Karen
authors.initials: K
authors.lastname: MacDonald
authors.affiliation: Division of Nuclear Medicine, Department of Medicine, the Ottawa Hospital, Ottawa, Ontario, Canada.
authors.forename: Eugene
authors.initials: E
authors.lastname: Leung
authors.affiliation: Molecular Function and Imaging Program, the National Cardiac PET Centre and the Arrhythmia Service, Division of Cardiology, Department of Medicine, University of Ottawa Heart Institute, Ottawa, Canada.
authors.forename: Girish
authors.initials: G
authors.lastname: Nair
authors.affiliation: Molecular Function and Imaging Program, the National Cardiac PET Centre and the Arrhythmia Service, Division of Cardiology, Department of Medicine, University of Ottawa Heart Institute, Ottawa, Canada.
authors.forename: Rob
authors.initials: R
authors.lastname: Beanlands
authors.affiliation: Molecular Function and Imaging Program, the National Cardiac PET Centre and the Arrhythmia Service, Division of Cardiology, Department of Medicine, University of Ottawa Heart Institute, Ottawa, Canada dbirnie@ottawaheart.ca.
authors.forename: David
authors.initials: D
authors.lastname: Birnie
mesh_terms: D016477:Artifacts; D001692:Biological Transport; D009202:Cardiomyopathies / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000503:physiopathology; D003326:Coronary Circulation; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000378:metabolism; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D000072078:Positron Emission Tomography Computed Tomography; D012507:Sarcoidosis / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000503:physiopathology
chemical_list: D019788:Fluorodeoxyglucose F18
keywords: FDG-PET; cardiac sarcoidosis; inter-observer agreement