Denoising of Dynamic Contrast-Enhanced MR Images Using Dynamic Nonlocal Means
Artikel i vetenskaplig tidskrift, 2010

This paper presents a new algorithm for denoising dynamic contrast-enhanced (DCE) MR images. It is a novel variation on the nonlocal means (NLM) algorithm. The algorithm, called dynamic nonlocal means (DNLM), exploits the redundancy of information in the temporal sequence of images. Empirical evaluations of the performance of the DNLM algorithm relative to seven other denoising methods-simple Gaussian filtering, the original NLM algorithm, a trivial extension of NLM to include the temporal dimension, bilateral filtering, anisotropic diffusion filtering, wavelet adaptive multiscale products threshold, and traditional wavelet thresholding-are presented. The evaluations include quantitative evaluations using simulated data and real data (20 DCE-MRI data sets from routine clinical breast MRI examinations) as well as qualitative evaluations using the same real data (24 observers: 14 image/signal-processing specialists, 10 clinical breast MRI radiographers). The results of the quantitative evaluation using the simulated data show that the DNLM algorithm consistently yields the smallest MSE between the denoised image and its corresponding original noiseless version. The results of the quantitative evaluation using the real data provide evidence, at the alpha = 0.05 level of significance, that the DNLM algorithm yields the smallest MSE between the denoised image and its corresponding original noiseless version. The results of the qualitative evaluation provide evidence, at the alpha = 0.05 level of significance, that the DNLM algorithm performs visually better than all of the other algorithms. Collectively the qualitative and quantitative results suggest that the DNLM algorithm more effectively attenuates noise in DCE MR images than any of the other algorithms.

noise removal

dynamic contrast-enhanced (dce) magnetic resonance imaging (mri)

magnetic-resonance images

anisotropic diffusion

perfusion

robust

dynamic nonlocal means (dnlm)

rician noise

denoising

noise

nonlocal means

space

filter

breast

Författare

Y. Gal

Andrew Mehnert

Chalmers, Signaler och system

A. P. Bradley

K. McMahon

D. Kennedy

S. Crozier

IEEE Transactions on Medical Imaging

0278-0062 (ISSN)

Vol. 29 302-310

Styrkeområden

Livsvetenskaper och teknik

Ämneskategorier

Signalbehandling

Datorseende och robotik (autonoma system)