Quantitative assessment of brain perfusion with magnetic resonance imaging

Abstract

This thesis focuses on assessing blood supply to brain tissue using MRI. For Dynamic Susceptibility Contrast-MRI a series of images is acquired during the passage of a bolus contrast agent through the brain up to the point that the contrast agent is equally mixed within the total blood pool. The tissue MR signal holds the hemodynamic information and the cerebral blood flow and volume. A reference or Arterial Input Function (AIF) measurement close to the brain tissue is required to enable quantification of perfusion. A special focus of this thesis lies on how to measure a correct AIF. A correct shape of the AIF is crucial for absolute or even relative perfusion values. A correct peak-height is necessary for absolute perfusion quantification, but an erroneous peak-height in combination with a correct shape of the AIF can still produce correct relative values for cerebral blood flow and volume. Therefore, the first objective should be to measure the correct shape of the AIF, whereas the measurement of the peak-height of the AIF should be considered of secondary importance.