title: Detection of simulated pulmonary embolism in a porcine model using hyperpolarized 3He MRI.
abstract: Several radiological imaging modalities are available to assist with the clinical diagnosis of pulmonary embolism (PE). The most frequently used techniques-nuclear medicine ventilation-perfusion (VP) scan, computed tomography (CT), magnetic resonance angiography (MRA), and pulmonary angiography (PA)-all have literature-supported, substantial limitations with respect to timeliness and patient safety. Hyperpolarized 3He magnetic resonance gas distribution imaging (HP 3He MRI) recently has shown potential as a safer and faster alternative. In this study, we performed HP 3He MRI on a porcine model (N = 6) of simulated PE using selective occlusion balloon catheterization (N = 4) and nonselective aged autologous clot injection (N = 1). The technique was also performed on a normal pig and again after the animal was killed. Temporal depletion of regional HP 3He MRI signal intensity provided for a qualitative assessment of simulated PE (N = 4), and regional PAO2 (alveolar partial pressure of oxygen) was calculated in affected airspaces for a quantitative assessment of simulated PE (N = 1). The preliminary results suggest that HP (3)He MRI shows promise as a means of assessing regional pulmonary perfusion abnormalities in the porcine models of simulated PE that were used in this study.
authors.affiliation: Department of Radiology, University of Pennsylvania Medical Center, Philadelphia, Pennsylvania 19104, USA.
authors.forename: Aman
authors.initials: A
authors.lastname: Jalali
authors.forename: Masaru
authors.initials: M
authors.lastname: Ishii
authors.forename: Johan M
authors.initials: JM
authors.lastname: Edvinsson
authors.forename: Liang
authors.initials: L
authors.lastname: Guan
authors.forename: Maxim
authors.initials: M
authors.lastname: Itkin
authors.forename: David A
authors.initials: DA
authors.lastname: Lipson
authors.forename: James E
authors.initials: JE
authors.lastname: Baumgardner
authors.forename: Rahim R
authors.initials: RR
authors.lastname: Rizi
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D006371:Helium; D007554:Isotopes; D008279:Magnetic Resonance Imaging / Q000379:methods*; D011655:Pulmonary Embolism / Q000175:diagnosis* / Q000473:pathology; D013552:Swine
chemical_list: D007554:Isotopes; D006371:Helium