A dynamic feedback algorithm to find the
optimal free-lunch (FL) bolus-length in a multi-TI Hadamard-encoding scheme is
presented. An estimated FL bolus-length is often not ideal for the examined
subject. In arterial spin labeling (ASL) this frequently results in unwanted
arterial transit-delay (ATD) artefacts. The proposed method allows approaching
the optimal FL bolus-length individually by analyzing intermediate decoded
perfusion-weighted images during a running MRI scan. The aim is to reduce the
FL bolus-length as much as necessary, but to keep it as long as possible to
yield maximal signal.
