title: A comparative study of different level interpolations for improving spatial resolution in diffusion tensor imaging.
abstract: This paper studies and evaluates the feasibility and the performance of different level interpolations for improving spatial resolution of diffusion tensor magnetic resonance imaging (DT-MRI or DTI). In particular, the following techniques are investigated: anisotropic interpolation operating on scalar gray-level images, log-Euclidean interpolation method, and the quaternion interpolation method, which operate on diffusion tensor fields. The performance is evaluated both qualitatively and quantitatively using criteria such as tensor determinant, fractional anisotropy (FA), mean diffusivity (MD), fiber length, etc. We conclude that tensor field interpolations allow avoiding undesirable swelling effect in DTI, which is not the case with scalar gray-level interpolation, and that scalar gray-level image interpolation and log-Euclidean tensor field interpolation suffer from decrease in FA and MD, which may mislead the interpretation of the clinical parameters FA and MD. In contrast, the quaternion tensor field interpolation avoids such FA and MD decrease, which suggests its use for clinical applications.
authors.forename: Feng
authors.initials: F
authors.lastname: Yang
authors.forename: Yue-Min
authors.initials: YM
authors.lastname: Zhu
authors.forename: Jian-Hua
authors.initials: JH
authors.lastname: Luo
authors.forename: Marc
authors.initials: M
authors.lastname: Robini
authors.forename: Jie
authors.initials: J
authors.lastname: Liu
authors.forename: Pierre
authors.initials: P
authors.lastname: Croisille
mesh_terms: D016880:Anisotropy; D003198:Computer Simulation; D016208:Databases, Factual; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D056324:Diffusion Tensor Imaging / Q000379:methods*; D006321:Heart / Q000502:physiology; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*