title: Comparing anisotropic diffusion filters for the enhancement of sodium magnetic resonance images.
abstract: The anisotropic diffusion (AND) filter, an image processing technique derived from physics, was applied to low-resolution sodium magnetic resonance imaging (MRI) to examine the possibilities of image enhancement by postprocessing. We compared six different variants of AND filters. Besides the qualitative good results on phantom measurements, quantitative analyses on MRI of human kidney yielded major improvements in noise reduction and other quality measures: the noise (i.e., the standard deviation in the image background) could be reduced to 1%-2% of its original value, while linear filters (Gaussian, Fermi, Hamming) achieved a reduction to 42%-64%. Besides that, less than 5% of structures and intensities are lost when using AND filters. Comparing the different variants, the two-dimensional and the three-dimensional AND filter outperformed the histogram-of-gradient and tensor-based AND filter. We envision that by using these AND filters, quantitative analysis of sodium MRI of kidney could be improved.
authors: Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, 68167 Mannheim, Germany.
authors: Christoph M
authors: CM
authors: Decker
authors: Frank G
authors: FG
authors: Zöllner
authors: Simon
authors: S
authors: Konstandin
authors: Lothar R
authors: LR
authors: Schad
mesh_terms: D000465:Algorithms; D016880:Anisotropy; D003287:Contrast Media / Q000493:pharmacokinetics; D005374:Filtration; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012964:Sodium / Q000493:pharmacokinetics; D006801:Humans
chemical_list: D003287:Contrast Media; D012964:Sodium