The impact of peak saturation of the arterial input function on quantitative evaluation of dynamic susceptibility contrast-enhanced MR studies

Purpose: The purpose of this work was to investigate systematic errors in d ynamic contrast-enhanced MR perfusion studies due to peak saturation of the arterial input function (AIF) and to introduce a simple correction algorit hm. Method: Computer simulations were performed to evaluate the influence of AI F peak saturation and to demonstrate the effectiveness of the presented cor rection algorithm. To compare the computer simulations with real MR data, M R perfusion measurements were performed on volunteers. Results: The computer simulations show that AIF peak saturation leads to a systematic overestimation of cerebral blood volume (CBV) and cerebral blood flow (CBF) values, which was confirmed by comparing the obtained MR data w ith PET results. With use of an improved calculation algorithm correcting f or AIF peak saturation, a significant improvement of the obtained CBV and C BF values could be demonstrated. Conclusion: Our results suggest that AIF peak saturation leads to a signifi cant systematic error in the determination of CBV and CBF values and has ne cessarily to he taken into account for dynamic contrast-enhanced MR perfusi on studies.