It has recently been shown that 17O magnetic resonance (MR) spectroscopic imaging at ultrahigh fields provides a reliable method for measuring CMRO2 during a short period of 17O2 gas inhalation. The mathematical (or complete) model used in the 17O MR method for calculating CMRO2 requires simultaneous measurements of multiple parameters including the concentration of H217O produced in the brain tissue from inhaled 17O2 gas (C b), CBF, and the input function for the H217O concentration in the feeding artery (Ca). Both invasive and noninvasive measurements are involved in determining all of these parameters. In this article, two simplified methods are proposed and validated for calculating CMRO2 based on 17O MR measurement(s): the first method requires the measurements of Cb and CBF, but not Ca, and the second method only requires a single noninvasive measurement of C b. The simplified methods were used to calculate CMRO2 in anesthetized rat brain, and the results were compared with those obtained using the complete model. The results from this work show (1) the validity of the simplified methods for quantifying CMRO2, and (2) the feasibility for establishing a completely noninvasive 17O MR approach for imaging CMRO2 in vivo.
|Original language||English (US)|
|Number of pages||9|
|Journal||Journal of Cerebral Blood Flow and Metabolism|
|State||Published - Aug 2004|
All Science Journal Classification (ASJC) codes
- Clinical Neurology
- Cardiology and Cardiovascular Medicine