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Comparative Study
. 2025 Apr 9;11(4):46.
doi: 10.3390/tomography11040046.

Temporal Shift When Comparing Contrast-Agent Concentration Curves Estimated Using Quantitative Susceptibility Mapping (QSM) and ΔR2*: The Association Between Vortex Parameters and Oxygen Extraction Fraction

Ronnie Wirestam  1 , Anna Lundberg  1 , Linda Knutsson  1   2   3 , Emelie Lind  1   4
Affiliations
Comparative Study

Temporal Shift When Comparing Contrast-Agent Concentration Curves Estimated Using Quantitative Susceptibility Mapping (QSM) and ΔR2*: The Association Between Vortex Parameters and Oxygen Extraction Fraction

Ronnie Wirestam et al. Tomography. .

Abstract

Background: When plotting data points corresponding to the contrast-agent-induced change in transverse relaxation rate from a dynamic gradient-echo (GRE) magnetic resonance imaging (MRI) study versus a corresponding spin-echo study, a loop or vortex curve rather than a reversible line is formed. The vortex curve area is likely to reflect vessel architecture and oxygenation level. In this study, the vortex effect seen when using only GRE-based estimates, i.e., contrast-agent concentration based on GRE transverse relaxation rate and contrast-agent concentration based on quantitative susceptibility mapping (QSM), was investigated.

Methods: Twenty healthy volunteers were examined using 3 T MRI. Magnitude and phase dynamic contrast-enhanced MRI (DSC-MRI) data were obtained using GRE echo-planar imaging. Vortex curves for grey-matter (GM) regions and for arterial input function (AIF) data were constructed by plotting concentration based on GRE transverse relaxation rate versus concentration based on QSM. Vortex parameters (vortex area and normalised vortex width) were compared with QSM-based whole-brain OEF estimates obtained using 3D GRE.

Results: An obvious vortex effect was observed, and both GM vortex parameters showed a moderate and significant correlation with OEF (r = -0.51, p = 0.02). The vortex parameters for AIF data showed no significant correlation with OEF.

Conclusions: GRE-based GM vortex parameters correlated significantly with whole-brain OEF. In agreement with expectations, the corresponding AIF data, representing high fractions of arterial blood, showed no significant correlation. Novel parameters, based solely on standard GRE protocols, are of relevance to investigate, considering that GRE-based DSC-MRI is very common in brain tumour applications.

Keywords: dynamic susceptibility contrast; hysteresis; magnetic susceptibility; microvasculature; oxygen extraction; quantitative susceptibility mapping; transverse relaxation rate; vortex.

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Conflict of interest statement

The authors have no conflicts of interest to declare.

Figures

Figure 1
Figure 1
Representative examples of registered grey-matter tissue vortex curves (in blue), based on contrast-agent concentration estimates obtained using ΔR2* and quantitative susceptibility mapping (QSM). The curves also illustrate the principle for extracting values of Λ = Δ/max[CΔR2*]. (a) Vortex curve showing clockwise direction (with Δ > 0). (b) Vortex curve showing counterclockwise direction (with Δ < 0).
Figure 2
Figure 2
(a) Relationship between grey-matter tissue vortex area and whole-brain average oxygen extraction fraction (OEF). The 95% CI of the slope was [–544.6, –46.7]. (b) Relationship between grey-matter tissue vortex Λ value and whole-brain average OEF. The 95% CI of the slope was [–0.0299, –0.0028]. The solid lines in (a,b) are the results of linear regression analyses.
Figure 3
Figure 3
(a) Relationship between grey-matter tissue vortex area and age. The 95% CI of the slope was [–100.3, 32.0]. (b) Relationship between grey-matter tissue Λ value and age. The 95% CI of the slope was [–0.00576, 0.00138]. The solid lines in (a,b) are the results of linear regression analyses. Note that the hypothesis that there is no linear relationship could not be rejected.
See this image and copyright information in PMC

References

    1. Boxerman J.L., Hamberg L.M., Rosen B.R., Weisskoff R.M. MR contrast due to intravascular magnetic susceptibility perturbations. Magn. Reson. Med. 1995;34:555–566. - PubMed
    1. Kiselev V.G., Strecker R., Ziyeh S., Speck O., Hennig J. Vessel size imaging in humans. Magn. Reson. Med. 2005;53:553–563. doi: 10.1002/mrm.20383. - DOI - PubMed
    1. Xu C., Kiselev V.G., Möller H.E., Fiebach J.B. Dynamic hysteresis between gradient echo and spin echo attenuations in dynamic susceptibility contrast imaging. Magn. Reson. Med. 2013;69:981–991. - PubMed
    1. Emblem K.E., Mouridsen K., Bjornerud A., Farrar C.T., Jennings D., Borra R.J., Wen P.Y., Ivy P., Batchelor T.T., Rosen B.R., et al. Vessel architectural imaging identifies cancer patient responders to anti-angiogenic therapy. Nat. Med. 2013;19:1178–1183. doi: 10.1038/nm.3289. - DOI - PMC - PubMed
    1. Hohmann A., Zhang K., Mooshage C.M., Jende J.M.E., Rotkopf L.T., Schlemmer H.P., Bendszus M., Wick W., Kurz F.T. Whole-brain vascular architecture mapping identifies region-specific microvascular profiles in vivo. AJNR Am. J. Neuroradiol. 2024;45:1346–1354. - PMC - PubMed

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