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arXiv · 1303.2439

Voxel-wise Weighted MR Image Enhancement using an Extended Neighborhood Filter

Joseph Suresh Paul·Joshin John Mathew·Souparnika Kandoth Naroth·Chandrasekar Kesavadas
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Abstract

We present an edge preserving and denoising filter for enhancing the features in images, which contain an ROI having a narrow spatial extent. Typical examples include angiograms, or ROI spatially distributed in multiple locations and contained within an outlying region, such as in multiple-sclerosis. The filtering involves determination of multiplicative weights in the spatial domain using an extended set of neighborhood directions. Equivalently, the filtering operation may be interpreted as a combination of directional filters in the frequency domain, with selective weighting for spatial frequencies contained within each direction. The advantages of the proposed filter in comparison to specialized non-linear filters, which operate on diffusion principle, are illustrated using numerical phantom data. The performance evaluation is carried out on simulated images from BrainWeb database for multiple-sclerosis, acute ischemic stroke using clinically acquired FLAIR images and MR angiograms.

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Joseph Suresh Paul, Joshin John Mathew, Souparnika Kandoth Naroth, Chandrasekar Kesavadas. 2013-03-11. Voxel-wise Weighted MR Image Enhancement using an Extended Neighborhood Filter. https://arxiv.org/abs/1303.2439

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