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arXiv · 2512.04586

Structure-Aware Adaptive Kernel MPPCA Denoising for Diffusion MRI

Ananya Singhal·Dattesh Dayanand Shanbhag·Sudhanya Chatterjee
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Abstract

Diffusion-weighted MRI (DWI) at high b-values often suffers from low signal-to-noise ratio (SNR), making image quality poor. Marchenko-Pastur PCA (MPPCA) is a popular method to reduce noise, but it uses a fixed patch size across the whole image, which doesn't work well in regions with different structures. To address this, we propose an adaptive kernel MPPCA (ak-MPPCA) that selects the best patch size for each voxel based on its local neighborhood. This improves denoising performance by better handling structural variations.

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Ananya Singhal, Dattesh Dayanand Shanbhag, Sudhanya Chatterjee. 2025-12-04. Structure-Aware Adaptive Kernel MPPCA Denoising for Diffusion MRI. https://arxiv.org/abs/2512.04586

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