title: Improved k-t BLAST and k-t SENSE using FOCUSS.
abstract: The dynamic MR imaging of time-varying objects, such as beating hearts or brain hemodynamics, requires a significant reduction of the data acquisition time without sacrificing spatial resolution. The classical approaches for this goal include parallel imaging, temporal filtering and their combinations. Recently, model-based reconstruction methods called k-t BLAST and k-t SENSE have been proposed which largely overcome the drawbacks of the conventional dynamic imaging methods without a priori knowledge of the spectral support. Another recent approach called k-t SPARSE also does not require exact knowledge of the spectral support. However, unlike k-t BLAST/SENSE, k-t SPARSE employs the so-called compressed sensing (CS) theory rather than using training. The main contribution of this paper is a new theory and algorithm that unifies the above mentioned approaches while overcoming their drawbacks. Specifically, we show that the celebrated k-t BLAST/SENSE are the special cases of our algorithm, which is asymptotically optimal from the CS theory perspective. Experimental results show that the new algorithm can successfully reconstruct a high resolution cardiac sequence and functional MRI data even from severely limited k-t samples, without incurring aliasing artifacts often observed in conventional methods.
authors.affiliation: Bio-Imaging & Signal Processing Lab., Korea Advanced Institute of Science & Technology (KAIST), 373-1 Guseong-Dong, Yuseong-Gu, Daejon 305-701, Korea.
authors.forename: Hong
authors.initials: H
authors.lastname: Jung
authors.forename: Jong Chul
authors.initials: JC
authors.lastname: Ye
authors.forename: Eung Yeop
authors.initials: EY
authors.lastname: Kim
mesh_terms: D000465:Algorithms; D016477:Artifacts; D001921:Brain / Q000000981:diagnostic imaging / Q000473:pathology*; D005583:Fourier Analysis; D006321:Heart / Q000000981:diagnostic imaging; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000295:instrumentation* / Q000379:methods; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D015233:Models, Statistical; D009206:Myocardium / Q000473:pathology; D016011:Normal Distribution; D011859:Radiography; D013997:Time Factors