120 likes | 231 Views
Accelerated mouse cardiac imaging using threefold undersampling and kt-BLAST reconstruction. 3847. Ian Marshall, Maurits A Jansen, Yuehui Tao, Gavin D Merrifield, Gillian A Gray University of Edinburgh. Computer 35. Mouse kt-BLAST cardiac imaging 3847. Introduction. Why acceleration?
E N D
Accelerated mouse cardiac imaging using threefold undersampling and kt-BLAST reconstruction 3847 Ian Marshall, Maurits A Jansen, Yuehui Tao, Gavin D Merrifield, Gillian A Gray University of Edinburgh Computer 35
Mouse kt-BLAST cardiac imaging3847 Introduction Why acceleration? - shorter scan times, reduced costs, - improved patient compliance - reduced animal burden Parallel imaging now widely used clinically (some) kt-undersampling for human cardiac scanning Limited translation of techniques to rodent imaging - would improve animal welfare (3Rs)
Mouse kt-BLAST cardiac imaging3847 Study design 6 healthy + 2 MI adult mice Cardiac MRI scans in short-axis plane Standard CINE sequence 3-fold accelerated ktBLAST sequence + training data Comparison of image quality and cardiac indices EDV, ESV, EF, EDM, ESM
Mouse kt-BLAST cardiac imaging3847 Scanning details 7T scanner (Agilent Technologies) 39 mm quad coil Respiratory gating and cardiac triggering CINE Gradient Echo sequence - (12 frames, 192×192, FOV 30 mm, 3 Averages) kt-BLAST sequence (Tsao MRM 2003) - 3× undersampling (linear grid) - 16 central training rows
Mouse kt-BLAST cardiac imaging3847 Image analysis One analyst, blinded to type of images Subjective quality (scale 1-5) Endo- and epicardial borders drawn manually Cardiological indices derived
Mouse kt-BLAST cardiac imaging3847 Images fully sampled 3× undersampled
Mouse kt-BLAST cardiac imaging3847 “Ratios” •=MI
Mouse kt-BLAST cardiac imaging3847 Bland-Altman plot EDV MI MI
Mouse kt-BLAST cardiac imaging3847 Results summary Image quality: 4.3±1.2 (full) versus 3.8±1.4 (ktBLAST) Cardiological indices (σ)wrt fully sampled images “Ratios” Bland-Altman bias EDV 0.94 (0.07) -5 (8) μL ESV 1.06 (0.14) 2 (6) μL EF 0.93 (0.08) -5 (5) % EDM1.11 (0.10) 13 (12) mg ESM 1.01 (0.06) 1 (8) mg
Mouse kt-BLAST cardiac imaging3847 Discussion kt-BLAST images have similar “quality” “Ratios” biased up to 11% (for EDM) - corresponding Bland-Altman bias 13 mg Observer variability 3-10% (Heijman JMRI 2008) MI mice (large hearts and small EF) Overall acceleration 2.4× Compare with Compressed Sensing (Wech JMRI 2011)
Mouse kt-BLAST cardiac imaging3847 Conclusion Accelerated cardiac imaging of mice is feasible Threefold acceleration gives acceptable results This enables - increased throughput - improved animal welfare
Mouse kt-BLAST cardiac imaging3847 Acknowledgements Peter Hoskins Tom Anderson Steven Fortune Mike Davies Gabriel Rilling Ross Lennen Agnieszka Kozak