Robert Merwa1,
Thorsten Feiweier2, Franz Ebner3, Gernot Reishofer3,
Karin Kapp4, Rudolf Stollberger5
1Medical Engineering, FH O - Upper
Austria University of Applied Sciences, Linz, Austria; 2Healthcare,
Siemens AG, Germany; 3Department of Radiology, Medical University
of Graz, Graz, Austria; 4Department of Radiation Therapy, Medical
University of Graz, Graz, Austria; 5Institute of Medical
Engineering, Graz University of Technology, Graz, Austria
The
determination of kinetic parameters depends strongly on the inhomogenities of
the RF-field. Due to the local magnitude of these inhomogenities the values
for the AIF and tissue concentrations are widespread which lead to an
overestimation or underestimation of Ktrans and Ve. An
essential improvement can be achieved if the dynamic data are corrected
accordingly. The absolute difference of Ktrans and Ve
obtained with the AIF in two comparable arteries can be improved by a factor
up to 33 when using the correction procedure. Also the statistical evaluation
of the data shows an improvement if B1 inhomogeneities are
corrected.