Significance of Subtle Diffusion Weighted Imaging Lesion Dynamics: A Comparative Analysis of Methods for Detecting Diffusion Weighted Imaging Lesion Reversal in Endovascular Stroke Treatment

Thor Håkon Skattør; Kine Mari Bakke; Terje Nome; Atle Bjørnerud; Brian Anthony Enriquez; Cecilie Mørck Offersen; Ingrid Digernes; Anne Hege Aamodt; Mona Kristiansen Beyer

doi:10.1161/SVIN.125.001835

Significance of Subtle Diffusion Weighted Imaging Lesion Dynamics: A Comparative Analysis of Methods for Detecting Diffusion Weighted Imaging Lesion Reversal in Endovascular Stroke Treatment

Stroke Vasc Interv Neurol. 2025 Nov 8;5(6):e001835. doi: 10.1161/SVIN.125.001835. eCollection 2025 Nov.

Authors

Thor Håkon Skattør^{1

2

3}, Kine Mari Bakke⁴, Terje Nome², Atle Bjørnerud^{4

5}, Brian Anthony Enriquez¹, Cecilie Mørck Offersen^{6

7}, Ingrid Digernes⁴, Anne Hege Aamodt^{1

8}, Mona Kristiansen Beyer^{2

3}

Affiliations

¹ Department of Neurology Oslo University Hospital Oslo Norway.
² Division of Radiology and Nuclear Medicine Oslo University Hospital Oslo Norway.
³ Institute of Clinical Medicine University of Oslo Oslo Norway.
⁴ Department of Physics and Computational Radiology Oslo University Hospital Oslo Norway.
⁵ Centre for Lifespan Changes in Brain and Cognition University of Oslo Oslo Norway.
⁶ Department of Radiology Copenhagen University Hospital Rigshospitalet Copenhagen Denmark.
⁷ Department of Clinical Medicine University of Copenhagen Copenhagen Denmark.
⁸ Department of Neuroscience and Movement Science The Norwegian University of Science and Technology Trondheim Norway.

Abstract

Background: Restrictive diffusion on magnetic resonance imaging is recognized as an early marker of ischemic brain damage, even though diffusion-weighted imaging lesion reversal (DWI-R) is well known. This study aimed to compare methodologies for detecting DWI-R, including voxel-based analysis, which captures subtle lesion dynamics, and to test their correlation with clinical outcomes.

Methods: We retrospectively analyzed magnetic resonance imaging data from 216 consecutive patients with acute ischemic stroke obtained before and after endovascular therapy. DWI-R was defined either as an increase in DWI-Alberta Stroke Program Early Computed Tomography Score, a decrease of total DWI signal volume or as partial reversal of the initial DWI lesion, irrespective of the final DWI load. Associations between 3-month poststroke modified Rankin scale score and DWI-R was assessed according to the different definitions of DWI-R using logistic binary regression.

Results: In patients undergoing endovascular therapy, 25% had increased DWI-Alberta Stroke Program Early Computed Tomography Score and 32% showed reduced DWI volume. Both measures were strongly associated with favorable outcomes (modified Rankin Scale score ≤2) with odds ratios of 4.90 and 5.60, respectively (95% CIs: 1.66-14.46 and 2.09-14.98). Voxel-based analysis revealed DWI-R of ≥20% of the initial lesion in 64.5% of cases. Even with an overall increase of lesion volume due to progression elsewhere, ≥20% reversal of initial lesion was associated with a significantly improved outcome compared with <20% reversal, odds ratio 2.22 (95% CIs: 1.05-4.70).

Conclusion: DWI-R was common in patients treated with endovascular therapy and linked to favorable outcomes. Subtle lesion dynamics detected only by the voxel-based analysis also conferred significant clinical benefits, supporting DWI-R as a continuum rather than a binary measure as "present" or "absent."