Assess whether MRI-derived pressure drop predicts plaque-surface WSS discrepancy

Determine whether pressure-drop estimates derived from 4D flow MRI velocity fields carry the same information as CFD-derived pressure drop for explaining the discrepancy between CFD-derived and MRI-derived plaque-surface wall shear stress.

Background

The exploratory regression found that CFD-derived pressure drop across the plaque was significantly associated with the discrepancy in mean plaque-surface wall shear stress, whereas stenosis degree was not significant in that model. However, pressure drop and CFD wall shear stress were both obtained from the same simulated flow field, so the association may partly reflect computational coupling rather than an independently validated relationship.

The paper notes that pressure drop can in principle be obtained from 4D flow velocity fields, but does not evaluate whether an MRI-derived pressure estimate provides comparable explanatory information. Independent validation would be needed before using pressure-informed corrections to MRI wall shear stress.

References

Third, whether an MRI-derived pressure drop, obtainable from 4D flow velocity fields, carries the same information was not tested.

— Comparative Evaluation of Carotid Artery Hemodynamics: Patient-Specific CFD Simulations vs. 4D flow MRI  (2609.17295 - Mokhtari et al., 15 Sep 2026) in Section "Discussion," subsection "Correlates of the Discrepancy"

Under the present acquisition and post-processing protocol, absolute plaque-surface WSS values from 4D flow MRI should be interpreted cautiously and should not be considered interchangeable with CFD-derived values; whether pressure-informed adjustments or hybrid MRI-CFD approaches can reduce the disagreement remains to be tested.

— Comparative Evaluation of Carotid Artery Hemodynamics: Patient-Specific CFD Simulations vs. 4D flow MRI  (2609.17295 - Mokhtari et al., 15 Sep 2026) in Section "Conclusion"