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Abstract #1462

Hyperpolarized 3He Magnetic Resonance Imaging ADC Gradients in Healthy Elderly Never-Smokers

Khadija Sheikh1, 2, Sarah Svenningsen1, 2, Miranda Kirby1, 2, David G. McCormack3, Grace Parraga1, 2

1Imaging Research Laboratories, Robarts Research Institute, London, Ontario, Canada; 2Medical Biophysics, Western University, London, Ontario, Canada; 3Division of Respirology, Western University, London, Ontario, Canada

It is unknown whether changes in 3He MRI apparent diffusion coefficient gradients in the superior-inferior (SI) and anterior-posterior (AP) direction occur during the aging process. We hypothesized that the anterior-posterior gradient is reduced during the aging process and that there is a significant relationship between the anterior-posterior gradient and age. Our objective was to quantitatively evaluate the anatomical distribution of ADC using hyperpolarized 3He MRI in healthy elderly never-smokers. We found that ADC anatomical differences in the anterior-posterior direction were significant and mean ADC was dependent on anterior-posterior location, but ADC gradients were not dependent on age.

Keywords

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