title: Physiologic characterization of inflammatory arthritis in a rabbit model with BOLD and DCE MRI at 1.5 Tesla.
abstract: OBJECTIVE
  Our aim was to test the feasibility of blood oxygen level dependent magnetic resonance imaging (BOLD MRI) and dynamic contrast-enhanced (DCE) MRI to monitor periarticular hypoxic/inflammatory changes over time in a juvenile rabbit model of arthritis.
  
  
  METHODS
  We examined arthritic and contralateral nonarthritic knees of 21 juvenile rabbits at baseline and days 1,14, and 28 after induction of arthritis by unilateral intra-articular injection of carrageenin with BOLD and DCE MRI at 1.5 Tesla (T). Nine noninjected rabbits served as controls. Associations between BOLD and DCE-MRI and corresponding intra-articular oxygen pressure (PO2) and blood flow [blood perfusion units (BPU)] (polarographic probes, reference standards) or clinical-histological data were measured by correlation coefficients.
  
  
  RESULTS
  Percentage BOLD MRI change obtained in contralateral knees correlated moderately with BPU on day 0 (r = -0.51, p = 0.02) and excellently on day 28 (r = -0.84, p = 0.03). A moderate correlation was observed between peak enhancement DCE MRI (day 1) and BPU measurements in arthritic knees (r = 0.49, p = 0.04). In acute arthritis, BOLD and DCE MRI highly correlated (r = 0.89, p = 0.04; r = 1.0, p < 0.0001) with histological scores in arthritic knees.
  
  
  CONCLUSIONS
  The proposed techniques are feasible to perform at 1.5 T, and they hold potential as surrogate measures to monitor hypoxic and inflammatory changes over time in arthritis at higher-strength MRI fields.
  
  
  CONCLUSIONS
  • BOLD and DCE MRI detect interval perisynovial changes in a rabbit knee • BOLD and DCE MRI act as surrogate markers of physiologic changes in arthritis • BOLD MRI signal represents oxygen extraction compared with intra-articular PO 2 • DCE MRI measurements estimate physiologic periarticular vascular properties • In rabbit knees with acute arthritis, BOLD/DCE MRI highly correlated with histological scores.
authors.affiliation: Department of Diagnostic Imaging, The Hospital for Sick Children, 555 University Avenue, Toronto, ON, Canada, M5G1X8.
authors.forename: Otilia C
authors.initials: OC
authors.lastname: Nasui
authors.forename: Michael W
authors.initials: MW
authors.lastname: Chan
authors.forename: George
authors.initials: G
authors.lastname: Nathanael
authors.forename: Adrian
authors.initials: A
authors.lastname: Crawley
authors.forename: Elka
authors.initials: E
authors.lastname: Miller
authors.forename: Jaques
authors.initials: J
authors.lastname: Belik
authors.forename: Hai-Ling
authors.initials: HL
authors.lastname: Cheng
authors.forename: Andrea
authors.initials: A
authors.lastname: Kassner
authors.forename: Tammy
authors.initials: T
authors.lastname: Rayner
authors.forename: Ruth
authors.initials: R
authors.lastname: Weiss
authors.forename: Garry
authors.initials: G
authors.lastname: Detzler
authors.forename: Anguo
authors.initials: A
authors.lastname: Zhong
authors.forename: Rahim
authors.initials: R
authors.lastname: Moineddin
authors.forename: Roland
authors.initials: R
authors.lastname: Jong
authors.forename: Marianne
authors.initials: M
authors.lastname: Rogers
authors.forename: Andrea S
authors.initials: AS
authors.lastname: Doria
mesh_terms: D000818:Animals; D003287:Contrast Media / Q000008:administration & dosage; D004195:Disease Models, Animal; D007270:Injections, Intra-Articular; D007719:Knee Joint / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology*; D017078:Laser-Doppler Flowmetry; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D020370:Osteoarthritis, Knee / Q000378:metabolism / Q000473:pathology* / Q000503:physiopathology; D010100:Oxygen / Q000378:metabolism*; D011817:Rabbits; D016059:Range of Motion, Articular; D012720:Severity of Illness Index
chemical_list: D003287:Contrast Media; D010100:Oxygen