title: Imaging of heterogeneous materials with a turbo spin echo single-point imaging technique.
abstract: A magnetic resonance imaging method is presented for imaging of heterogeneous broad linewidth materials. This method allows for distortionless relaxation weighted imaging by obtaining multiple phase encoded k-space data points with each RF excitation pulse train. The use of this method, turbo spin echo single-point imaging-(turboSPI), leads to decreased imaging times compared to traditional constant-time imaging techniques, as well as the ability to introduce spin-spin relaxation contrast through the use of longer effective echo times. Imaging times in turboSPI are further decreased through the use of low flip angle steady-state excitation. Two-dimensional images of paramagnetic doped agarose phantoms were obtained, demonstrating the contrast and resolution characteristics of the sequence, and a method for both amplitude and phase deconvolution was demonstrated for use in high-resolution turboSPI imaging. Three-dimensional images of a partially water-saturated porous volcanic aggregate (T(2L) approximately 200 ms, Deltanu(1/2) approximately 2500 Hz) contained in a hardened white Portland cement matrix (T(2L) approximately 0.5 ms, Deltanu(1/2) approximately 2500 Hz) and a water-saturated quartz sand (T(2) approximately 300 ms, T(2)(*) approximately 800 microseconds) are shown.
authors.affiliation: MRI Centre, University of New Brunswick, Fredericton, New Brunswick, E3B 5A3, Canada.
authors.forename: S D
authors.initials: SD
authors.lastname: Beyea
authors.forename: B J
authors.initials: BJ
authors.lastname: Balcom
authors.forename: I V
authors.initials: IV
authors.lastname: Mastikhin
authors.forename: T W
authors.initials: TW
authors.lastname: Bremner
authors.forename: R L
authors.initials: RL
authors.lastname: Armstrong
authors.forename: P E
authors.initials: PE
authors.lastname: Grattan-Bellew
mesh_terms: D019327:Copper Sulfate / Q000737:chemistry*; D017352:Echo-Planar Imaging; D007091:Image Processing, Computer-Assisted; D008903:Minerals / Q000737:chemistry*; D019047:Phantoms, Imaging; D016062:Porosity; D012680:Sensitivity and Specificity; D012685:Sepharose / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry*; D013113:Spin Labels; D014867:Water / Q000032:analysis*
chemical_list: D008903:Minerals; D013113:Spin Labels; D014867:Water; D012822:Silicon Dioxide; D012685:Sepharose; D019327:Copper Sulfate