Comparison of arterial input function models for small-animal ultrasound perfusion imaging

Quantitative ultrasound perfusion imaging is used to estimate tissue perfusion parameters, such as blood flow, blood volume and mean transit time. The bolus & burst method is one possible approach to quantitative ultrasound perfusion imaging. It is based on a pharmacokinetic model where the tissue intensity curves are modeled as a convolution of an arterial input function (AIF) and an impulse residue function. Two AIF models have been presented for the bolus & burst method so far based on two lognormal and three gamma variate functions. The aim of this contribution is to suggest other alternative AIF models and test their suitability for the bolus & burst method for small-animal applications by comparison with measured AIFs.