Egbert J. W. Bleeker1, Andrew G. Webb1, Marianne A. A. van Walderveen2, Mark A. van Buchem1,2, Matthias J. P. van Osch1
Local or regional arterial input function (AIF) measurements aim for voxel specific AIFs from small arteries. These local AIFs are assumed to reflect the true input of the microvasculature much better than global AIFs. However, do the measured local AIFs reflect the true concentration-time curve of small arteries? The current study investigated this question with numerical modeling that simulated partial volume effects in local AIF measurements. In addition, local AIF candidates selected using angiograms were evaluated in vivo. The findings suggest that local AIF measurements do not reflect the true concentration-time curve in small arteries.