title: Improved image reconstruction of low-resolution multichannel phase contrast angiography.
abstract: In low-resolution phase contrast magnetic resonance angiography, the maximum intensity projected channel images will be blurred with consequent loss of vascular details. The channel images are enhanced using a stabilized deblurring filter, applied to each channel prior to combining the individual channel images. The stabilized deblurring is obtained by the addition of a nonlocal regularization term to the reverse heat equation, referred to as nonlocally stabilized reverse diffusion filter. Unlike reverse diffusion filter, which is highly unstable and blows up noise, nonlocal stabilization enhances intensity projected parallel images uniformly. Application to multichannel vessel enhancement is illustrated using both volunteer data and simulated multichannel angiograms. Robustness of the filter applied to volunteer datasets is shown using statistically validated improvement in flow quantification. Improved performance in terms of preserving vascular structures and phased array reconstruction in both simulated and real data is demonstrated using structureness measure and contrast ratio.
authors.affiliation: Indian Institute of Information Technology and Management-Kerala , Medical Image Computing and Signal Processing Laboratory, Trivandrum 695581, Kerala, India.
authors.forename: Akshara
authors.initials: A
authors.lastname: P Krishnan
authors.affiliation: Indian Institute of Information Technology and Management-Kerala , Medical Image Computing and Signal Processing Laboratory, Trivandrum 695581, Kerala, India.
authors.forename: Ajin
authors.initials: A
authors.lastname: Joy
authors.affiliation: Indian Institute of Information Technology and Management-Kerala , Medical Image Computing and Signal Processing Laboratory, Trivandrum 695581, Kerala, India.
authors.forename: Joseph Suresh
authors.initials: JS
authors.lastname: Paul
keywords: maximum intensity projection; multichannel parallel images; nonlocal reverse diffusion; phase contrast magnetic resonance angiography; phased array reconstruction
references.citation: Med Phys. 1996 Jun;23(6):857-69
references.pmid: 8798171
references.citation: Quant Imaging Med Surg. 2014 Apr;4(2):136-44
references.pmid: 24834426
references.citation: IEEE Trans Med Imaging. 2004 Dec;23(12):1490-507
references.pmid: 15575407
references.citation: Med Image Anal. 1998 Sep;2(3):243-60
references.pmid: 9873902
references.citation: J Magn Reson Imaging. 1991 Jul-Aug;1(4):405-13
references.pmid: 1790362
references.citation: Magn Reson Med. 2007 Dec;58(6):1182-95
references.pmid: 17969013
references.citation: IEEE Trans Image Process. 2000;9(2):256-66
references.pmid: 18255392
references.citation: Magn Reson Med. 1994 Sep;32(3):330-4
references.pmid: 7984065
references.citation: J Magn Reson Imaging. 2004 May;19(5):632-9
references.pmid: 15112314
references.citation: IEEE Trans Image Process. 1998;7(3):421-32
references.pmid: 18276262
references.citation: IEEE Trans Image Process. 1996;5(11):1539-53
references.pmid: 18290071
references.citation: IEEE Trans Image Process. 2012 Mar;21(3):983-95
references.pmid: 21937351