Absolute quantification of perfusion by dynamic susceptibility contrast MRI using Bookend and VASO steady-state CBV calibration: a comparison with pseudo-continuous ASL

Abstract

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Dynamic susceptibility contrast perfusion MRI using phase-based venous output functions: comparison with pseudo-continuous arterial spin labelling and assessment of contrast agent concentration in large veins

“…It is interesting to note that the observed value of approximately 32 mM −1 s −1 is considerably lower than the prediction by Kjølby et al of r2* = 87 mM −1 s −1 [4]. The ASL-based estimates showed even lower GM CBF variability and range [cf., 30], but this can, in part, be attributed to lower ASL spatial resolution and associated tissue partial volume effects. We applied the mean r2* estimate of 32 mM −1 s −1 , obtained in this study, for DSC-MRI quantification in absolute terms, merely in order to facilitate comparisons with other CBF data in terms of inter-individual variability and range.…”

A linear mixed perfusion model for tissue partial volume correction of perfusion estimates in dynamic susceptibility contrast MRI: Impact on absolute quantification, repeatability, and agreement with pseudo-continuous arterial spin labeling

“…Smoothed data are also shown in Figure and, although it was not part of the statistical analysis, it is clear that smoothing considerably reduces the CV. Note that repeatability assessments of this data set (without PVC) have been reported previously , although not on a voxel‐by‐voxel level as presented here.…”

“…Note that mLTS ends up with fewer voxels in the regression analysis (10 voxels here) compared with LR. [For more details regarding the different methods, see the respective references describing them (6,8,(19)(20)(21). ]…”

Comparison of Quantitative Cerebral Blood Flow Measurements Performed by Bookend Dynamic Susceptibility Contrast and Arterial Spin-Labeling MRI in Relapsing-Remitting Multiple Sclerosis

“…We observed generally smallest slopes in Pearson correlations for WM (Table 2) regions which is consistent with our observation of mean differences (Table 3) being largest in WM. Recent work by Lindgren et al 44 comparing Bookend and pCASL techniques in healthy controls showing similar ROI CBF values after sequence calibration, but lower Pearson correlation coefficients despite achieving similar results on Bland-Altman analysis. The correlation difference may be due to post processing techniques, as we included an automatic rejection of intermediate CBF images effected by patient head motion which was shown to increase SNR relative to other techniques 27 .…”