Correction for arterial-tissue delay and dispersion in absolute quantitative cerebral perfusion DSC MR imaging.

The singular value decomposition deconvolution of cerebral tissue concentration-time curves with the arterial input function is commonly used in dynamic susceptibility contrast cerebral perfusion MR imaging. However, it is sensitive to the time discrepancy between the arrival of the bolus in the tissue concentration-time curve and the arterial input function signal. This normally causes inaccuracy in the quantitative perfusion maps due to delay and dispersion effects. A comprehensive correction algorithm has been achieved through slice-dependent time-shifting of the arterial input function, and a delay-dependent dispersion correction model. The correction algorithm was tested in 11 healthy subjects and three ischemic stroke patients scanned with a quantitative perfusion pulse sequence at 1.5 T. A validation study was performed on five patients with confirmed cerebrovascular occlusive disease scanned with MRI and positron emission tomography at 3.0 T. A significant effect (P < 0.05) was reported on the quantitative cerebral blood flow and mean transit time measurements (up to 50%). There was no statistically significant effect on the quantitative cerebral blood volume values. The in vivo results were in agreement with the simulation results, as well as previous literature. This minimizes the bias in patient diagnosis due to the existing errors and artifacts in dynamic susceptibility contrast imaging.