Advancing the applicability to extract physiological parameters using Arterial Spin Labeling

Abstract

Arterial Spin Labeling (ASL) is a non-invasive MRI technique for measuring perfusion without the need for contrast agents, as it utilizes the blood itself. ASL can quantify not only blood flow but also other hemodynamical parameters, such as transit times and exchange rates within organs. The first part of this work introduces an extended quantification model, incorporating an additional intravoxel transit time parameter that differentiates between transit and exchange mechanisms. Conducted simulations show that neglecting transit effects leads to a compensation in the exchange parameter. The second part of this thesis explores the use of velocity selective ASL for robust extracerebral measurements. This sophisticated technique offers flexibility for imaging organs with low blood flow velocities or unclear feeding vessels. The focus is on breast and liver imaging.