Matthew R. Orton1, Michael Germuska1, Keiko Miyazaki1, Dow-Mu Koh2, David J. Collins1, Martin O. Leach1
1Clinical Magentic Resonance Research Group, Institute of Cancer Research, Sutton, Surrey, UK; 2Academic Department of Radiology, Royal Marsden Hospital, Sutton, Surrey, UK
Use of a spoiled gradient echo dynamic imaging sequence is proposed for use with a pre-bolus of contrast to estimate the arterial input function (AIF) in the descending aorta with a single coronal slice. This approach avoids many of the problems associated with obtaining the AIF from the main dynamic data, particularly temporal resolution and partial volume issues with small vessels. Due to the flow speed of aortic blood, the steady-state assumption for signal quantification no longer applies. Non-steady-state estimation results in an increase in the concentration estimates of around 25% compared to steady-state estimation.