title: Hybrid-SPRITE MRI.
abstract: In a FID based frequency encoding MRI experiment the central part of k-space is not generally accessible due to the probe dead time. This portion of k-space is however crucial for image reconstruction. SPRITE (Single Point Ramped Imaging with T1 Enhancement), SPI with a linearly ramped phase encode gradient, has been employed to image short relaxation time systems for many years with great success. It is a robust imaging method in significant measure because it provides acquisition of high quality k-space origin data. We propose a new sampling scheme, termed hybrid-SPRITE, combining phase and frequency encoding to ensure high quality images with reduced acquisition times, reduced gradient duty cycle and increased sensitivity. In hybrid-SPRITE, numerous time domain points are collected to assist image reconstruction. An Inverse Non-uniform Discrete Fourier Transform (INDFT) is employed in 1D applications. A pseudo-polar grid is exploited in 2D hybrid-SPRITE for rapid and accurate image reconstruction.
authors.affiliation: MRI Research Center, Department of Physics, University of New Brunswick, 8 Bailey Drive, Fredericton, NB E3B 5A3, Canada. Electronic address: d.x@unb.ca.
authors.forename: Dan
authors.initials: D
authors.lastname: Xiao
authors.forename: Bruce J
authors.initials: BJ
authors.lastname: Balcom
mesh_terms: D000465:Algorithms; D005583:Fourier Analysis; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy; D019047:Phantoms, Imaging; D011846:Radio Waves
keywords: Frequency and phase encoding; Inverse Non-uniform Discrete Fourier Transform; Profiles; Pseudo-polar grid; SPRITE; Sensitivity