title: Imaging of the diaphragm: anatomy and function.
abstract: The diaphragm is the primary muscle of ventilation. Dysfunction of the diaphragm is an underappreciated cause of respiratory difficulties and may be due to a wide variety of entities, including surgery, trauma, tumor, and infection. Diaphragmatic disease usually manifests as elevation at chest radiography. Functional imaging with fluoroscopy (or ultrasonography or magnetic resonance imaging) is a simple and effective method of diagnosing diaphragmatic dysfunction, which can be classified as paralysis, weakness, or eventration. Diaphragmatic paralysis is indicated by absence of orthograde excursion on quiet and deep breathing, with paradoxical motion on sniffing. Diaphragmatic weakness is indicated by reduced or delayed orthograde excursion on deep breathing, with or without paradoxical motion on sniffing. Eventration is congenital thinning of a segment of diaphragmatic muscle and manifests as focal weakness. Treatment of diaphragmatic paralysis depends on the cause of the dysfunction and the severity of the symptoms. Treatment options include plication and phrenic nerve stimulation. Supplemental material available at http://radiographics.rsna.org/lookup/suppl/doi:10.1148/rg.322115127/-/DC1.
authors.affiliation: Department of Radiology, University of Washington Medical Center, 1959 NE Pacific St, Box 357115, Seattle, WA 98195, USA.
authors.forename: Laura K
authors.initials: LK
authors.lastname: Nason
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Walker
authors.forename: Michael F
authors.initials: MF
authors.lastname: McNeeley
authors.forename: Wanaporn
authors.initials: W
authors.lastname: Burivong
authors.forename: Corinne L
authors.initials: CL
authors.lastname: Fligner
authors.forename: J David
authors.initials: JD
authors.lastname: Godwin
mesh_terms: D003952:Diagnostic Imaging / Q000379:methods*; D003964:Diaphragm / Q000033:anatomy & histology* / Q000000981:diagnostic imaging / Q000196:embryology / Q000294:innervation / Q000502:physiology*; D003965:Diaphragmatic Eventration / Q000000981:diagnostic imaging / Q000209:etiology / Q000473:pathology; D004558:Electric Stimulation; D005471:Fluoroscopy / Q000379:methods; D006548:Hernia, Diaphragmatic / Q000000981:diagnostic imaging / Q000196:embryology / Q000473:pathology / Q000601:surgery; D006549:Hernia, Diaphragmatic, Traumatic; D065630:Hernias, Diaphragmatic, Congenital; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D010791:Phrenic Nerve / Q000502:physiology; D015656:Respiratory Mechanics; D012133:Respiratory Paralysis / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery / Q000628:therapy; D014463:Ultrasonography