title: Diffusion-weighted hyperpolarized 129Xe MRI in healthy volunteers and subjects with chronic obstructive pulmonary disease.
abstract: Given its greater availability and lower cost, (129) Xe apparent diffusion coefficient (ADC) MRI offers an alternative to (3) He ADC MRI. To demonstrate the feasibility of hyperpolarized (129) Xe ADC MRI, we present results from healthy volunteers (HV), chronic obstructive pulmonary disease (COPD) subjects, and age-matched healthy controls (AMC). The mean parenchymal ADC was 0.036 ± 0.003 cm(2) sec(-1) for HV, 0.043 ± 0.006 cm(2) sec(-1) for AMC, and 0.056 ± 0.008 cm(2) sec(-1) for COPD subjects with emphysema. In healthy individuals, but not the COPD group, ADC decreased significantly in the anterior-posterior direction by ∼ 22% (P = 0.006, AMC; 0.0059, HV), likely because of gravity-induced tissue compression. The COPD group exhibited a significantly larger superior-inferior ADC reduction (∼ 28%) than the healthy groups (∼ 24%) (P = 0.00018, HV; P = 3.45 × 10(-5) , AMC), consistent with smoking-related tissue destruction in the superior lung. Superior-inferior gradients in healthy subjects may result from regional differences in xenon concentration. ADC was significantly correlated with pulmonary function tests (forced expiratory volume in 1 sec, r = -0.77, P = 0.0002; forced expiratory volume in 1 sec/forced vital capacity, r = -0.77, P = 0.0002; diffusing capacity of carbon monoxide in the lung/alveolar volume (V(A) ), r = -0.77, P = 0.0002). In healthy groups, ADC increased with age by 0.0002 cm(2) sec(-1) year(-1) (r = 0.56, P = 0.02). This study shows that (129) Xe ADC MRI is clinically feasible, sufficiently sensitive to distinguish HV from subjects with emphysema, and detects age- and posture-dependent changes.
authors.affiliation: Department of Radiology, Center for In Vivo Microscopy, Duke University Medical Center, Durham, North Carolina 27710, USA.
authors.forename: S Sivaram
authors.initials: SS
authors.lastname: Kaushik
authors.forename: Zackary I
authors.initials: ZI
authors.lastname: Cleveland
authors.forename: Gary P
authors.initials: GP
authors.lastname: Cofer
authors.forename: Gregory
authors.initials: G
authors.lastname: Metz
authors.forename: Denise
authors.initials: D
authors.lastname: Beaver
authors.forename: John
authors.initials: J
authors.lastname: Nouls
authors.forename: Monica
authors.initials: M
authors.lastname: Kraft
authors.forename: William
authors.initials: W
authors.lastname: Auffermann
authors.forename: Jan
authors.initials: J
authors.lastname: Wolber
authors.forename: H Page
authors.initials: HP
authors.lastname: McAdams
authors.forename: Bastiaan
authors.initials: B
authors.lastname: Driehuys
mesh_terms: D000280:Administration, Inhalation; D000328:Adult; D000368:Aged; D003287:Contrast Media / Q000008:administration & dosage; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D008168:Lung / Q000473:pathology; D008297:Male; D008875:Middle Aged; D029424:Pulmonary Disease, Chronic Obstructive / Q000175:diagnosis*; D019275:Radiopharmaceuticals / Q000008:administration & dosage; D012016:Reference Values; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014979:Xenon Isotopes / Q000008:administration & dosage
chemical_list: D003287:Contrast Media; D019275:Radiopharmaceuticals; D014979:Xenon Isotopes