title: Grating-based X-ray Dark-field Computed Tomography of Living Mice.
abstract: Changes in x-ray attenuating tissue caused by lung disorders like emphysema or fibrosis are subtle and thus only resolved by high-resolution computed tomography (CT). The structural reorganization, however, is of strong influence for lung function. Dark-field CT (DFCT), based on small-angle scattering of x-rays, reveals such structural changes even at resolutions coarser than the pulmonary network and thus provides access to their anatomical distribution. In this proof-of-concept study we present x-ray in vivo DFCTs of lungs of a healthy, an emphysematous and a fibrotic mouse. The tomographies show excellent depiction of the distribution of structural - and thus indirectly functional - changes in lung parenchyma, on single-modality slices in dark field as well as on multimodal fusion images. Therefore, we anticipate numerous applications of DFCT in diagnostic lung imaging. We introduce a scatter-based Hounsfield Unit (sHU) scale to facilitate comparability of scans. In this newly defined sHU scale, the pathophysiological changes by emphysema and fibrosis cause a shift towards lower numbers, compared to healthy lung tissue.
authors.affiliation: Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, Garching, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Velroyen
authors.affiliation: Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, Garching, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Yaroshenko
authors.affiliation: Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, Garching, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Hahn
authors.affiliation: Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, Garching, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Fehringer
authors.affiliation: Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, Garching, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Tapfer
authors.affiliation: Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, Garching, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Müller
authors.affiliation: Department of Radiology, Technische Universität München, Munich, Germany.
authors.forename: P B
authors.initials: PB
authors.lastname: Noël
authors.affiliation: Bruker microCT, Kontich, Belgium.
authors.forename: B
authors.initials: B
authors.lastname: Pauwels
authors.affiliation: Bruker microCT, Kontich, Belgium.
authors.forename: A
authors.initials: A
authors.lastname: Sasov
authors.affiliation: Comprehensive Pneumology Center, Institute of Lung Biology and Disease, Helmholtz Zentrum München and Ludwig-Maximilians-University Hospital Munich, Munich, Germany ; German Center for Lung Research (DZL), Germany.
authors.forename: A Ö
authors.initials: AÖ
authors.lastname: Yildirim
authors.affiliation: Comprehensive Pneumology Center, Institute of Lung Biology and Disease, Helmholtz Zentrum München and Ludwig-Maximilians-University Hospital Munich, Munich, Germany ; German Center for Lung Research (DZL), Germany.
authors.forename: O
authors.initials: O
authors.lastname: Eickelberg
authors.affiliation: Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Hellbach
authors.affiliation: Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany.
authors.forename: S D
authors.initials: SD
authors.lastname: Auweter
authors.affiliation: Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany.
authors.forename: F G
authors.initials: FG
authors.lastname: Meinel
authors.affiliation: Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany ; German Center for Lung Research (DZL), Germany.
authors.forename: M F
authors.initials: MF
authors.lastname: Reiser
authors.affiliation: Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, Garching, Germany ; Medical Radiation Physics, Lund University, Lund, Sweden.
authors.forename: M
authors.initials: M
authors.lastname: Bech
authors.affiliation: Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, Garching, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Pfeiffer
mesh_terms: D000818:Animals; D005260:Female; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D008171:Lung Diseases / Q000000981:diagnostic imaging / Q000473:pathology; D051379:Mice; D023421:Models, Animal; D014057:Tomography, X-Ray Computed / Q000379:methods*
keywords: Dark-field computed tomography; Dark-field imaging; Pulmonary emphysema; Pulmonary fibrosis; X-ray phase-contrast imaging