Sebastian C. Niesporek1, Reiner Umathum1, Thomas M. Fiedler1, and Armin M. Nagel1,2
1Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany, 2Diagnostic and Interventional Radiology, University Medical Center Ulm, Ulm, Germany
The
energy balance of a cell is closely connected to in-vivo H217O-concentration
which also is the turnover product of oxidative phosphorylation. 17O-MRI
during inhalation of 17O2 enables localized mapping of cerebral metabolic rate of oxygen
consumption (CMRO2). Larger voxel sizes due to a low
MR-sensitivity and short relaxation times induce partial volume effects which reduce
quantification accuracy. For accurate signal correction exact T2*-values
are essential. A partial volume correction algorithm for improved T2*-determination
where T2*-values are adapted iteratively is presented.
Consistent results to simulations were obtained for phantom and in-vivo data.
The iteratively corrected in-vivo T2*-values were used
for improved 17O-MRI-signal quantification.