title: Improved diffusion imaging through SNR-enhancing joint reconstruction.
abstract: Quantitative diffusion imaging is a powerful technique for the characterization of complex tissue microarchitecture. However, long acquisition times and limited signal-to-noise ratio represent significant hurdles for many in vivo applications. This article presents a new approach to reduce noise while largely maintaining resolution in diffusion weighted images, using a statistical reconstruction method that takes advantage of the high level of structural correlation observed in typical datasets. Compared to existing denoising methods, the proposed method performs reconstruction directly from the measured complex k-space data, allowing for gaussian noise modeling and theoretical characterizations of the resolution and signal-to-noise ratio of the reconstructed images. In addition, the proposed method is compatible with many different models of the diffusion signal (e.g., diffusion tensor modeling and q-space modeling). The joint reconstruction method can provide significant improvements in signal-to-noise ratio relative to conventional reconstruction techniques, with a relatively minor corresponding loss in image resolution. Results are shown in the context of diffusion spectrum imaging tractography and diffusion tensor imaging, illustrating the potential of this signal-to-noise ratio-enhancing joint reconstruction approach for a range of different diffusion imaging experiments.
authors.affiliation: Department of Electrical and Computer Engineering, Beckman Institute for Advanced Science and Technology, University of Illinois, Urbana, Illinois, USA. jhaldar@usc.edu
authors.forename: Justin P
authors.initials: JP
authors.lastname: Haldar
authors.forename: Van J
authors.initials: VJ
authors.lastname: Wedeen
authors.forename: Marzieh
authors.initials: M
authors.lastname: Nezamzadeh
authors.forename: Guangping
authors.initials: G
authors.lastname: Dai
authors.forename: Michael W
authors.initials: MW
authors.lastname: Weiner
authors.forename: Norbert
authors.initials: N
authors.lastname: Schuff
authors.forename: Zhi-Pei
authors.initials: ZP
authors.lastname: Liang
mesh_terms: D000818:Animals; D001921:Brain; D003198:Computer Simulation; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D051379:Mice