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AIF and deconvolution

Dynamic susceptibility contrast magnetic resonance imaging (DSC-MRI) is widely used for measuring cerebral perfusion. Both the selection of an arterial input function (AIF) and the following deconvolution of the AIF with the tissue concentration curve are crucial steps in the process converting the measured tissue concentration curves, ct(t), into reliable estimates of CBF, CBV, MTT and Tmax. Several studies have shown that perfusion parameters can be used in acute stroke patients for delineating the ischemic, yet salvageable, tissue (penumbra) [1, 2]. Although surrogate indices such as time to peak and first moment can be readily obtained from ct(t), such parameters are confounded by the underlying vascular architecture, cardiac output and injection rate [3, 4]. Here we will discuss various techniques for estimating perfusion parameters by deconvolution with an AIF.