title: Improving Signal-to-Noise Ratio in Susceptibility Weighted Imaging: A Novel Multicomponent Non-Local Approach.
abstract: In susceptibility-weighted imaging (SWI), the high resolution required to obtain a proper contrast generation leads to a reduced signal-to-noise ratio (SNR). The application of a denoising filter to produce images with higher SNR and still preserve small structures from excessive blurring is therefore extremely desirable. However, as the distributions of magnitude and phase noise may introduce biases during image restoration, the application of a denoising filter is non-trivial. Taking advantage of the potential multispectral nature of MR images, a multicomponent approach using a Non-Local Means (MNLM) denoising filter may perform better than a component-by-component image restoration method. Here we present a new MNLM-based method (Multicomponent-Imaginary-Real-SWI, hereafter MIR-SWI) to produce SWI images with high SNR and improved conspicuity. Both qualitative and quantitative comparisons of MIR-SWI with the original SWI scheme and previously proposed SWI restoring pipelines showed that MIR-SWI fared consistently better than the other approaches. Noise removal with MIR-SWI also provided improvement in contrast-to-noise ratio (CNR) and vessel conspicuity at higher factors of phase mask multiplications than the one suggested in the literature for SWI vessel imaging. We conclude that a proper handling of noise in the complex MR dataset may lead to improved image quality for SWI data.
authors.affiliation: Advanced Biomedical Sciences Department, University of Napoli "Federico II", Napoli, Italy; IRCCS SDN, Naples, Italy.
authors.forename: Pasquale
authors.initials: P
authors.lastname: Borrelli
authors.affiliation: Institute of Biostructures and Bioimaging, National Research Council, Napoli, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Palma
authors.affiliation: Advanced Biomedical Sciences Department, University of Napoli "Federico II", Napoli, Italy.
authors.forename: Enrico
authors.initials: E
authors.lastname: Tedeschi
authors.affiliation: Advanced Biomedical Sciences Department, University of Napoli "Federico II", Napoli, Italy.
authors.forename: Sirio
authors.initials: S
authors.lastname: Cocozza
authors.affiliation: Institute of Biostructures and Bioimaging, National Research Council, Napoli, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Comerci
authors.affiliation: Institute of Biostructures and Bioimaging, National Research Council, Napoli, Italy.
authors.forename: Bruno
authors.initials: B
authors.lastname: Alfano
authors.affiliation: The MRI Institute for Biomedical Research, Detroit, MI, United States of America.
authors.forename: E Mark
authors.initials: EM
authors.lastname: Haacke
authors.affiliation: IRCCS SDN, Naples, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Salvatore
mesh_terms: D000465:Algorithms; D006801:Humans; D007089:Image Enhancement; D059629:Signal-To-Noise Ratio