title: Volumetric late gadolinium-enhanced myocardial imaging with retrospective inversion time selection.
abstract: OBJECTIVE
  To develop and validate a novel free-breathing 3D radial late gadolinium-enhanced magnetic resonance imaging technique (3D LGE-MRI) with isotropic resolution and retrospective inversion time (TI) selection for myocardial viability imaging.
  
  
  METHODS
  The 3D radial LGE-MRI method featuring an interleaved and bit-reversed radial k-space trajectory was evaluated in 12 subjects that also had clinical breath-hold Cartesian 2D LGE-MRI. The 3D LGE-MRI acquisition requires a predicted TI and a user-controlled data acquisition window that determines the sampling width around the predicted TI. Sliding window reconstructions with update rates of 1× the repetition time (TR) allow for a user selectable TI to obtain the maximum nulling of the myocardium. The retrospective nature of the acquisition allows the user to choose from a range of possible TI times centered on the expected TI. Those projections most corrupted by respiratory motion, as determined by a respiratory bellows signal, were resampled according to the diminishing variance algorithm. The quality of the left ventricular myocardial nulling on the 3D LGE-MRI and 2D LGE-MRI was assessed using a 4-point Likert scale by two experienced radiologists. Comparison of image quality scores for the two methods was performed using generalized estimating equations.
  
  
  RESULTS
  All 3D LGE-MRI cases produced similar nulling of myocardial signal as the 2D LGE-MRI. The image quality of myocardial nulling was not significantly different between the two acquisitions (mean nulling of 3.4 for 2D vs. 3.1 for 3D, and P = 0.0645). The average absolute deviation from mean scores was also not determined to be statistically significant (1.8 for 2D and 0.4 for 3D and P = 0.1673). Total acquisition time was ∼9 minutes for 3D LGE-MRI with voxel sizes ranging from 1.6(3) to 2.0(3) mm(3) . Conversely, the total imaging time was twice as long for the 2D DCE-MRI (>17 minutes) with an eight times larger voxel size of 1.4 × 2.2 × 7.0 mm.
  
  
  CONCLUSIONS
  The 3D LGE-MRI technique demonstrated in this study is a promising alternative for the assessment of myocardial viability in patients who have difficulty sustaining breath-holds for the clinical standard 2D LGE-MRI.
authors: Department of Physics, University of Wisconsin, Madison, Wisconsin, USA; Department of Medical Physics, University of Wisconsin, Madison, Wisconsin, USA.
authors: Steve
authors: S
authors: Kecskemeti
authors: Kevin
authors: K
authors: Johnson
authors: Christopher J
authors: CJ
authors: François
authors: Mark L
authors: ML
authors: Schiebler
authors: Orhan
authors: O
authors: Unal
mesh_terms: D000465:Algorithms; D003287:Contrast Media; D005682:Gadolinium; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D009203:Myocardial Infarction / Q000150:complications / Q000473:pathology*; D015203:Reproducibility of Results; D055425:Respiratory-Gated Imaging Techniques / Q000379:methods*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D018487:Ventricular Dysfunction, Left / Q000209:etiology / Q000473:pathology*
chemical_list: D003287:Contrast Media; D005682:Gadolinium
keywords: delayed contrast imaging; inversion recovery; left ventricle; myocardial viability; non-Cartesian; radial k-space trajectory; volumetric imaging
references: Magn Reson Med. 1992 Dec;28(2):275-89
references: 1461126
references: Magn Reson Med. 2004 May;51(5):1055-60
references: 15122690
references: Magn Reson Med. 2009 Jan;61(1):215-21
references: 19097213
references: J Magn Reson Imaging. 2006 Mar;23(3):323-30
references: 16456820
references: Radiology. 2004 Dec;233(3):921-6
references: 15516607
references: Magn Reson Med. 2005 Aug;54(2):476-80
references: 16032682
references: Radiology. 2004 Mar;230(3):845-51
references: 14990846
references: Radiology. 2001 Jan;218(1):215-23
references: 11152805
references: Magn Reson Med. 1995 Sep;34(3):412-22
references: 7500881
references: Circulation. 2002 Jan 29;105(4):539-42
references: 11815441
references: Magn Reson Med. 2001 Feb;45(2):206-11
references: 11180427
references: Magn Reson Med. 2002 Feb;47(2):372-83
references: 11810682
references: J Magn Reson Imaging. 2011 Dec;34(6):1465-71
references: 21972108
references: Circulation. 1995 Oct 1;92(7):1902-10
references: 7671375
references: Magn Reson Med. 2011 May;65(5):1269-77
references: 21500255
references: Magn Reson Med. 2007 May;57(5):821-7
references: 17457875
references: Magn Reson Med. 2006 May;55(5):1150-6
references: 16598720
references: J Magn Reson Imaging. 2007 Oct;26(4):927-33
references: 17896381
references: Magn Reson Med. 2002 Mar;47(3):529-38
references: 11870840
references: Invest Radiol. 2006 Sep;41(9):661-7
references: 16896300
references: Magn Reson Med. 2002 Aug;48(2):297-305
references: 12210938
references: Magn Reson Med. 2007 Aug;58(2):365-72
references: 17654582
references: Magn Reson Med. 1990 Nov;16(2):192-225
references: 2266841