Anatomical distribution of 3He apparent diffusion coefficients in severe chronic obstructive pulmonary disease.
OBJECTIVE
To evaluate the anatomical distribution of apparent diffusion coefficients (ADC) using hyperpolarized helium-3 (3He) MRI in chronic obstructive pulmonary disease (COPD).


METHODS
Hyperpolarized 3He MRI was performed in eight healthy and seven COPD subjects under breathhold conditions in the supine position to determine ADC values from diffusion-weighted images and evaluate anterior-posterior (AP) and superior-inferior (SI) differences.


RESULTS
ADC differences between anterior and posterior slices, DeltaAP, was 0.06 +/-0.01 cm2/second for healthy volunteers and 0.04 +/-0.02 cm2/second for COPD subjects and was significant for each subject (P < 0.01). The AP ADC gradient was -3.98 x 10(-3) +/-0.59 cm2/second/cm for healthy volunteers and -2.04 x 10(-3) +/-0.89 cm2/second/cm for COPD subjects. The difference in ADC between superior and inferior regions of interest (ROIs), DeltaSI, was 0.02 +/-0.02 cm2/second for healthy volunteers and 0.10 +/-0.09 cm2/second for COPD subjects, which was significant for each subject (P < 0.05). The SI ADC gradient was -0.63 x 10(-3) +/-2.23 cm2/second/cm for healthy volunteers and -6.61 x 10(-3) +/-6.68 cm2/second/cm for COPD subjects. DeltaAP, AP-gradient, and SI-gradient were significantly different between healthy volunteers and COPD subjects (P < 0.05).


CONCLUSIONS
In all subjects, ADC anatomical differences were significant and mean ADC was dependent on anatomic location and disease status.
Evans
Andrea
A
Imaging Research Laboratories, Robarts Research Institute, London, Ontario, Canada.
McCormack
David
D
Ouriadov
Alexei
A
Etemad-Rezai
Roya
R
Santyr
Giles
G
Parraga
Grace
G
D000368:Aged; D000704:Analysis of Variance; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D006371:Helium; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007554:Isotopes; D008297:Male; D019047:Phantoms, Imaging; D029424:Pulmonary Disease, Chronic Obstructive / Q000378:metabolism*; D012129:Respiratory Function Tests; D018709:Statistics, Nonparametric; D016683:Supine Position
D007554:Isotopes; D006371:Helium