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Abstract #0821

A Multiple-Breath 3He Wash-In Regimen to Reduce the Limitation of 3He PAO2-Imaging Due to Delayed Ventilation and Slow Filling

Hooman Hamedani1, Stephen J. Kadlececk1, Biao Han1, Kiarash Emami1, Yi Xin1, Masaru Ishii2, Milton Rossman3, Rahim Rizi1

1Department of Radiology, University of Pennsylvania, Philadelphia, PA, United States; 2Otolarynology, Johns Hopkins Medical Center, Baltimore, MD, United States; 3Pulmonary, allergy and Critical Care Division, University of Pennsylvania, Philadelphia, PA, United States

The precision of hyperpolarized pAO2-imaging is diminished by abnormal flows that may occur during the required breath-hold, which can then result in implausible, non-physiologic values. It is shown here that a sequence of progressive breaths of hyperpolarized 3He prior to the pAO2-imaging not only improves the level of signal-to-noise, but also produces a more uniform distribution of imaging gas in parenchyma, ultimately resulting in more reasonable pAO2-maps. In addition, filling the poorly ventilated regions of the lung by progressive wash-in breaths provides information about these regions that is unavailable due to lack of signal when using the single-breath protocols.

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Keywords

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