Article Text
Abstract
Objectives Late gadolinium enhancement (LGE) sequences have evolved. Free-breathing, motion-corrected LGE (MOCO-LGE)1,2 has several potential advantages over breath held LGE (bh-LGE)3 including minimal user input for the LGE short axis (SA) stack and no need for breath-holds. We hypothesised that the use of MOCO-LGE would be faster, cheaper and easier for clinical scanning, increasing throughput.
Methods 200 consecutive clinical patients underwent bh-LGE or MOCO-LGE at 1.5T. Image quality (Figure 1), scan time, patient throughput (change-over time) and reader confidence were compared. LGE image quality was evaluated qualitatively (adaption of previously reported method)4 and quantitatively (assessing image texture heterogenity using grayscale lacunarity, λ).
Adapted Quality Scoring Method for LGE images in CMR: 10 criteria; range of scores 0 (optimal quality) to 31 (poorest quality).
Example images from a single patient showing bh-LGE image (left) with corresponding MOCO-LGE (right).
Results MOCO-LGE image quality was better than bh-LGE qualitatively (lower score better: 0.56±1.2 vs 1.93±0.83, p<0.0001) especially in clinically vulnerable patients eg. atrial fibrillation , poor breath-holding, low ejection fraction (0.59 vs 3.05, p=0.0001). Excellent image quality (score=0) was also more common (78% vs 27%, p<0.0001). Quantitative image quality was superior with MOCO-LGE (lower score better: blood pool lambda bh-LGE 0.38±0.11 vs MOCO-LGE 0.28±0.08, p<0.0001). MOCO-LGE led to greater diagnostic confidence (blinded review: basic analytic, retained diagnostic and “Omary” correction methods, respectively p=0.005; p=0.018, p<0.001). Although patient change-over time did not differ significantly between scan protocols, total LGE imaging time was 1.6 times shorter with MOCO-LGE compared to bh-LGE (5.23 vs 8.84 minutes, p<0.0001).
Conclusion MOCO-LGE is superior to bh-LGE in a clinical service, with better image quality, easier interpretation and faster scanning times.
References
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References2. Peter Kellman, Andrew EArai. Cardiac imaging techniques for physicians: Late enhancement. JMRI Published Online First : 17 Aug 2012.3. Piehler KM, Wong TC, Puntil KS, et al. Free-breathing, motion-corrected late gadolinium enhancement is robust and extends risk stratification to vulnerable patients. Circ Cardiovasc Imaging 2013;6(3):423-32.4. Vincenzo Klinke, Stefano Muzzarelli, Nathalie Lauriers, et al. Quality assessment of cardiovascular magnetic resonance in the setting of the European CMR registry: description and validation of standardized criteria. J Cardiovasc Magn Reson 2013;15:55.