Dynamic susceptibility contrast MRI

Introduction Quantitative dynamic susceptibility contrast perfusion MRI (DSC-MRI) is based on the monitoring of the first passage of a bolus of contrast agent through the brain tissue and a brain-feeding artery. The contrast agent is injected rapidly by means of an MRinjector in the antecubital vein in the patients arm and a saline flush is used to push the contrast agent into the direction of the heart. Continuously dynamic T2 (*) weighted scanning with a temporal resolution of approximately 12 seconds is used to monitor the passage of the contrast agent through the brain tissue and an artery. The change in MR signal is subsequently converted into the concentration of contrast agent based on the physical properties of the contrast agent. The passage of the contrast agent through the brain-feeding artery is called the arterial input function (AIF). Deconvolving the passage through the brain tissue with the arterial input function, results in the tissue response function. Based on the theory of tracer kinetics, perfusion parameters are calculated from this tissue response function, i.e. cerebral blood flow (CBF) is the maximum value of the response function, cerebral blood volume (CBV) the area under the curve, and the mean transit time (MTT) follows from the central volume theorem: MTT=CBV/CBF. In this presentation, the acquisition, post-processing and pitfalls of DSC-MRI will be discussed and it will be highlighted on which topics more research is needed.