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bioRxiv · 10.1101/2025.08.31.673334

Optimized Quantitative Susceptibility Mapping at 7T MRI for Assessing Iron Deposition in Alzheimers Disease

Ma, F.·Ozbay, P. S.·Bilgic, B.·Hedden, T.·Delman, B.·Balchandani, P.·Alipour, A.
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Abstract

INTRODUCTIONElevated brain iron levels are common in Alzheimers disease (AD). Quantitative Susceptibility Mapping (QSM) is an advanced MRI technique for assessing iron accumulation. The optimized QSM at 7 Tesla (7T) MRI may further improve the sensitivity to detect subtle susceptibility changes in AD. METHODSWe optimized a QSM processing pipeline for 7T MRI by systematically comparing multiple reconstruction algorithms. Evaluation criteria included image quality, artifact suppression, and anatomical clarity. The finalized pipeline was applied to individuals with AD and healthy controls (HCs). RESULTSThe results revealed significantly elevated magnetic susceptibility values in the globus pallidus and dentate nucleus of the AD group compared to HCs. These findings were confirmed through both visual inspection and quantitative analysis of high-resolution QSM maps. DISCUSSIONOur results highlight the importance of optimizing QSM pipelines at 7T for accurate susceptibility quantification. We identified an optimal pipeline suitable for future applications in patients with AD and other neurological conditions.

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Ma, F., Ozbay, P. S., Bilgic, B., Hedden, T., Delman, B., Balchandani, P., Alipour, A.. 2025-09-01. Optimized Quantitative Susceptibility Mapping at 7T MRI for Assessing Iron Deposition in Alzheimers Disease. https://doi.org/10.1101/2025.08.31.673334

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