Benefits of Short Bolus ASL

Matthias Gnther¹

Usually, a long labeled blood bolus is used in arterial spin labeling (ASL) to yield optimal signal-to-noise ratios in perfusion-weighted images. In this work, properties of short bolus ASL is examined and demonstrated. Benefits of this approach include the approximate measurement of the tissue response curve and the precise probing of properties of parts of the arterial tree. Based on the ASL data with a short bolus length BL data sets can be reconstructed with a virtual bolus length, which is a multiple of BL. This allows calculating ASL time series with a bolus length of e.g. 2500ms, which usually cannot be measured in reality. The deviation between true and calculated bolus is less than 1% for common parameters. Short bolus ASL might probe sensitive to changes due to neuro-degenerative or small vessel disease.