Mastrodicasa Domenico, Elgavish Gabriel A, Schoepf U Joseph, Suranyi Pal, van Assen Marly, Albrecht Moritz H, De Cecco Carlo N, van der Geest Rob J, Hardy Rayphael, Mantini Cesare, Griffith L Parkwood, Ruzsics Balazs, Varga-Szemes Akos
Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, South Carolina, USA.
Department of Neuroscience and Imaging, Section of Diagnostic Imaging and Therapy - Radiology Division, SS. Annunziata Hospital, "G. d'Annunzio" University, Chieti, Italy.
J Magn Reson Imaging. 2018 Feb 15. doi: 10.1002/jmri.25973.
Binary threshold-based quantification techniques ignore myocardial infarct (MI) heterogeneity, yielding substantial misquantification of MI.
To assess the technical feasibility of MI quantification using percent infarct mapping (PIM), a prototype nonbinary algorithm, in patients with suspected MI.
Prospective cohort POPULATION: Patients (n = 171) with suspected MI referred for cardiac MRI.
FIELD STRENGTH/SEQUENCE: Inversion recovery balanced steady-state free-precession for late gadolinium enhancement (LGE) and modified Look-Locker inversion recovery (MOLLI) T -mapping on a 1.5T system.
Infarct volume (IV) and infarct fraction (IF) were quantified by two observers based on manual delineation, binary approaches (2-5 standard deviations [SD] and full-width at half-maximum [FWHM] thresholds) in LGE images, and by applying the PIM algorithm in T and LGE images (PIM ; PIM ).
IV and IF were analyzed using repeated measures analysis of variance (ANOVA). Agreement between the approaches was determined with Bland-Altman analysis. Interobserver agreement was assessed by intraclass correlation coefficient (ICC) analysis.
MI was observed in 89 (54.9%) patients, and 185 (38%) short-axis slices. IF with 2, 3, 4, 5SDs and FWHM techniques were 15.7 ± 6.6, 13.4 ± 5.6, 11.6 ± 5.0, 10.8 ± 5.2, and 10.0 ± 5.2%, respectively. The 5SD and FWHM techniques had the best agreement with manual IF (9.9 ± 4.8%) determination (bias 1.0 and 0.2%; P = 0.1426 and P = 0.8094, respectively). The 2SD and 3SD algorithms significantly overestimated manual IF (9.9 ± 4.8%; both P < 0.0001). PIM measured significantly lower IF (7.8 ± 3.7%) compared to manual values (P < 0.0001). PIM , however, showed the best agreement with the PIM reference (7.6 ± 3.6%, P = 0.3156). Interobserver agreement was rated good to excellent for IV (ICCs between 0.727-0.820) and fair to good for IF (0.589-0.736).
The application of the PIM technique for MI quantification in patients is feasible. PIM , with its ability to account for voxelwise MI content, provides significantly smaller IF than any thresholding technique and shows excellent agreement with the T -based reference.
2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2018.
基于二元阈值的量化技术忽略了心肌梗死（MI）的异质性，导致MI的大量错误量化。
评估使用梗死百分比映射（PIM）（一种原型非二元算法）对疑似MI患者进行MI量化的技术可行性。
前瞻性队列
因疑似MI接受心脏磁共振成像检查的患者（n = 171）。
场强/序列：在1.5T系统上采用反转恢复平衡稳态自由进动序列进行延迟钆增强（LGE）成像，并采用改良Look-Locker反转恢复（MOLLI）序列进行T映射。
两名观察者基于手动勾勒、LGE图像中的二元方法（2-5个标准差[SD]和半高宽[FWHM]阈值）以及在T和LGE图像中应用PIM算法（PIM ；PIM ）对梗死体积（IV）和梗死分数（IF）进行量化。
使用重复测量方差分析（ANOVA）分析IV和IF。采用Bland-Altman分析确定不同方法之间的一致性。通过组内相关系数（ICC）分析评估观察者间的一致性。
89例（54.9%）患者观察到MI，共185个短轴切片。采用2、3、4、5个SD和FWHM技术得到的IF分别为15.7±6.6%、13.4±5.6%、11.6±5.0%、10.8±5.2%和10.0±5.2%。5个SD和FWHM技术与手动测量的IF（9.9±4.8%）一致性最佳（偏差分别为1.0%和0.2%；P分别为0.1426和0.8094）。2个SD和3个SD算法显著高估了手动测量的IF（9.9±4.8%；两者P均<0.0001）。与手动测量值相比，PIM测量的IF显著更低（7.8±3.7%）（P<0.0001）。然而，PIM 与PIM参考值一致性最佳（7.6±3.6%，P = 0.3156）。观察者间对于IV的一致性评分为良好至优秀（ICC在0.727 - 0.820之间），对于IF的一致性评分为中等至良好（0.589 - 0.736）。
PIM技术在患者中进行MI量化的应用是可行的。PIM能够考虑体素层面的MI含量，与任何阈值技术相比，其得到的IF显著更小，并且与基于T的参考值具有良好的一致性。
2级 技术效能：1期 《磁共振成像杂志》2018年刊
