Evaluating Volumetric and White Matter Hyperintensity Lesion Measures for Low-field MRI using WMH-SynthSeg

Sep 30, 2026

Uploaded by James

White matter hyperintensities (WMH) predict amyloid-related imaging abnormalities (ARIA) in Alzheimer patients receiving anti-amyloid immunotherapy. The study evaluates FreeSurfer WMH-SynthSeg for extracting WMH lesions and brain volumetric changes from low-field MRI, aiming to reduce safety risks versus high-field MRI. Low-field scans were acquired on a portable 0.064T system and compared with 3T MRI, assessing volumetric agreement, WMH lesion localization, and group differences with ARIA stratification.

LanguageEnglish

CategoryHealthcare

FormatPDF

Pages5

Reading Time13 min

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Abstract

Background

Method

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DOI: 10. 1002/alz70856_106017 BIOMARKERS POSTER PRESENTATION NEUROIMAGING Evaluating Volumetric and White Matter Hyperintensity Lesion Measures for Low-field MRI using WMH-SynthSeg Hope Shimony1 Sarah J. Keefe 1 Kavon J Sharifi 1 Jude-Patrick Nnamdi Okafor 1 Nelly Joseph-Mathurin 1 Jessica N Banks 1 Jessica Hu2 Stephen Jarman 1 Edmond Knopp3 Madeline Paczynski 1 Joo Lim 1 Alexandra Venuto 1 Nupur Ghoshal 1 B. Joy Snider 1, 4 Shaney Flores 1 Tammie L.S. Benzinger4, 5 1Washington University School of Medicine, St. Louis, MO, USA 2Washington University in St. Louis, St. Louis, MO, USA 3 Hyperfine, White Plains, NY, USA 4 Knight Alzheimer Disease Research Center, St. Louis, MO, USA 5Washington University School of Medicine in St. Louis, St. Louis, MO, USA Correspondence Hope Shimony, Washington University School of Medicine, St. Louis, MO, USA. Email: [hope.shimony@wustl.edu](hope.shimony@wustl.edu) Abstract Background: White matter hyperintensities (WMH) are known predictors of amyloid-related imaging abnormalities (ARIA) in patients undergoing anti-amyloid immunotherapy (AAT) for Alzheimer disease. WMHsand brain volumetric changes can potentially be captured by low-field magnetic resonance imaging (MRI) that imposes minimal safety risks to those with contraindicators to high-field MRI. We investigate the recently released FreeSurfer WMH-SynthSeg for volumetric and WMH lesion processing of low-field MRI and its comparability to 3T MRI. Method: Low-field head MRI scans for 19 healthy controls and 23 patients undergoing AAT were acquired on a 0.064T Hyperfine SwoopÒ Portable MRI scanner. Treated patients also underwent a 3T MRI for ARIA screening by a clinical neuro-radiologist per treatment protocol. Volumetric measures of cortical grey matter, white matter, ventricles, and hippocampus were extracted from WMH-SynthSeg for low-field and FreeSurfer-7.4 for 3T MRI. WMH lesion probability maps were generated for all participants from WMH-SynthSeg. Linear regressions examined agreement between volumetrics for low-field and 3T MRI in treated patients without ARIA. Spatial localization of WMH lesions with ARIA pathology were visually assessed and compared with the clinical 3T scan. Finally, WMH volume measures were assessed amongst healthy controls and patients with and without ARIA using a pairwise Wilcoxon with Benjamini-Hochberg correction for multiple comparisons. Result: Four patients were clinically identified as having ARIA with cerebral edema (ARIA-E) from 3T MRI. WMH-SynthSeg estimates of lateral ventricular, white matter, and cortical grey matter volumes agreed with 3T MRI but tended to be significantly underestimated for the hippocampus (Figure 1). WMH lesion probability maps aligned This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. © 2025 The Alzheimer’s Association. Alzheimer’s & Dementia published by Wiley Periodicals LLC on behalf of Alzheimer’s Association. Alzheimer’s Dement. 2025;21(Suppl. 2):e106017. [https://doi.org/10.1002/alz70856_106017](https://doi.org/10.1002/alz70856_106017) wi[leyonlinelibrary.com/journal/alz](leyonlinelibrary.com/journal/alz) 1of5 BIOMARKERS with known ARIA but failed to capture the entire area affected (Figure 2). While WMH volumes for healthy controls were significantly lower than those on AAT therapy, WMH volumes were not significantly different betweenAAT patientswith and without ARIA-E (Figure 3). Conclusion: WMH-SynthSeg provides comparable volumetric measures to 3T for large brain regions and can spatially capture known ARIA. However, in our small sample, these measures were not sensitive enough to fully identify areas of ARIA. Further development is needed to improve small region quantification and WMH lesion detection, particularly at low-fields. BIOMARKERS BIOMARKER

FAQs

What problem does the study address for Alzheimer ARIA monitoring?

WMH are known predictors of ARIA during anti-amyloid immunotherapy, and capturing WMH-related changes with safer low-field MRI could support monitoring for patients who cannot undergo high-field MRI.

How were low-field and 3T MRI data used in the evaluation?

Low-field head MRI scans were collected on a 0.064T portable scanner for healthy controls and ARIA-screened patients, and treated patients also underwent 3T MRI for ARIA screening; WMH-SynthSeg outputs were compared against 3T FreeSurfer processing.

What were the main findings about WMH-SynthSeg performance?

WMH-SynthSeg agreed with 3T MRI for several large brain regions, but tended to underestimate hippocampal volume, and in a small sample it did not fully capture ARIA-affected areas.

Sep 30, 2026

Uploaded by James