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Abstract #1220

Relaxation Effects of Oxygen on T2 and T1 with Application to Vitreous PO2 Measurement

Eric R. Muir1, Yi Zhang1, Jinqi Li1, Oscar San Emeterio Nateras1, Wei Zhou1, Timothy O. Duong2

1Research Imaging Institute, University of Texas Health Science Center, San Antonio, TX, United States; 2Research Imaging Institute, UT Health Science Center at San Antonio, San Antonio, TX, United States

Abnormal vitreal oxygen tension (pO2) is implicated in some ocular and retinal diseases. Paramagnetic molecular oxygen shortens water T1, an effect which has been used to non-invasively map pO2 of body fluids. Paramagnetic agents should also affect T2, but the effect of oxygen on T2 has yet to be thoroughly explored. The aim of this study was to develop and calibrate MRI measurement of T1 and T2 with oxygen and apply these methods to non-invasively measure pO2 of the vitreous. Vitreous pO2 from T1 was more accurate than T2, likely due to the higher sensitivity of T2 to protein.

Keywords

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