title: Phase-contrast helium-3 MRI of aerosol deposition in human airways.
abstract: One of the key challenges in the study of health-related aerosols is predicting and monitoring sites of particle deposition in the respiratory tract. The potential health risks of ambient exposure to environmental or workplace aerosols and the beneficial effects of medical aerosols are strongly influenced by the site of aerosol deposition along the respiratory tract. Nuclear medicine is the only current modality that combines quantification and regional localization of aerosol deposition, and this technique remains limited by its spatial and temporal resolutions and by patient exposure to radiation. Recent work in MRI has shed light on techniques to quantify micro-sized magnetic particles in living bodies by the measurement of associated static magnetic field variations. With regard to lung MRI, hyperpolarized helium-3 may be used as a tracer gas to compensate for the lack of MR signal in the airways, so as to allow assessment of pulmonary function and morphology. The extrathoracic region of the human respiratory system plays a critical role in determining aerosol deposition patterns, as it acts as a filter upstream from the lungs. In the present work, aerosol deposition in a mouth-throat phantom was measured using helium-3 MRI and compared with single-photon emission computed tomography. By providing high sensitivity with high spatial and temporal resolutions, phase-contrast helium-3 MRI offers new insights for the study of particle transport and deposition.
authors.affiliation: Imagerie par Résonance Magnétique Médicale et Multi-Modalités (UMR8081), IR4M, Université Paris-Sud, CNRS, Orsay, France; Department of Physics, Harvard University, Cambridge, MA, USA; MGH/A. A. Martinos Center for Biomedical Imaging, Boston, MA, USA.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Sarracanie
authors.forename: Denis
authors.initials: D
authors.lastname: Grebenkov
authors.forename: Julien
authors.initials: J
authors.lastname: Sandeau
authors.forename: Soulé
authors.initials: S
authors.lastname: Coulibaly
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Martin
authors.forename: Kyle
authors.initials: K
authors.lastname: Hill
authors.forename: José Manuel
authors.initials: JM
authors.lastname: Pérez Sánchez
authors.forename: Redouane
authors.initials: R
authors.lastname: Fodil
authors.forename: Lionel
authors.initials: L
authors.lastname: Martin
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Durand
authors.forename: Georges
authors.initials: G
authors.lastname: Caillibotte
authors.forename: Daniel
authors.initials: D
authors.lastname: Isabey
authors.forename: Luc
authors.initials: L
authors.lastname: Darrasse
authors.forename: Jacques
authors.initials: J
authors.lastname: Bittoun
authors.forename: Xavier
authors.initials: X
authors.lastname: Maître
mesh_terms: D000336:Aerosols / Q000008:administration & dosage*; D003287:Contrast Media; D006371:Helium; D006801:Humans; D021621:Imaging, Three-Dimensional; D007501:Iron / Q000378:metabolism; D060526:Magnetic Fields; D008279:Magnetic Resonance Imaging / Q000379:methods*; D019047:Phantoms, Imaging; D012137:Respiratory System / Q000033:anatomy & histology*; D015899:Tomography, Emission-Computed, Single-Photon; D014057:Tomography, X-Ray Computed
chemical_list: D000336:Aerosols; D003287:Contrast Media; D006371:Helium; D007501:Iron
keywords: SPECT; aerosol deposition; drug administration; helium-3 MRI; human airways