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Abstract #3992

Repeatability Study of Regional Measurements of Alveolar Oxygen Tension in Humans by Hyperpolarized 3He MRI

Hooman Hamedani1, Masaru Ishii2, Kiarash Emami1, Stephen J. Kadlecek1, Yi Xin1, Puttisarn Mongkolwisetwara1, Nicholas N. Kuzma1, Biao Han1, Harrison McAdams3

1Radiology, University of Pennsylvania, Philadelphia, PA, United States; 2Otolaryngology - Head and Neck Surgery, Johns Hopkins University, Baltimore, MD, United States; 3Biological Basis of Behavior Program, University of Pennsylvania, Philadelphia, PA, United States; 4Radiology, University of Virginia, Charlottesville, VA, United States; 5Medicine, University of Pennsylvania, Philadelphia, PA, United States

Four healthy non-smokers and four asymptomatic smokers underwent three repetitions of hyperpolarized 3He MRI imaging in a two-week period to obtain a measure of intraclass test-retest repeatability for an oxygen-weighted 3He MRI scheme to measure the regional alveolar partial pressure of oxygen. 12 slices were imaged during a 12-second breath-hold with a reasonable spatial resolution. Inter and intraclass repeatability was measured for both global and regional distributions of partial pressure of oxygen in subjects. A mixed-effect model with random effects was regressed to 3x3x3 cm3 voxels of all human subjects to estimate a correlation coefficient for each group.

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Keywords

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