Zhang Lin, Huttin Olivier, Marie Pierre-Yves, Felblinger Jacques, Beaumont Marine, Chillou Christian DE, Girerd Nicolas, Mandry Damien
INSERM, U947, IADI, Nancy, F-54000, France.
Université de Lorraine, Nancy, F-54000, France.
J Magn Reson Imaging. 2016 Nov;44(5):1206-1217. doi: 10.1002/jmri.25285. Epub 2016 Apr 20.
To compare three widely used methods for myocardial infarct (MI) sizing on late gadolinium-enhanced (LGE) magnetic resonance (MR) images: manual delineation and two semiautomated techniques (full-width at half-maximum [FWHM] and n-standard deviation [SD]).
3T phase-sensitive inversion-recovery (PSIR) LGE images of 114 patients after an acute MI (2-4 days and 6 months) were analyzed by two independent observers to determine both total and core infarct sizes (TIS/CIS). Manual delineation served as the reference for determination of optimal thresholds for semiautomated methods after thresholding at multiple values. Reproducibility and accuracy were expressed as overall bias ± 95% limits of agreement.
Mean infarct sizes by manual methods were 39.0%/24.4% for the acute MI group (TIS/CIS) and 29.7%/17.3% for the chronic MI group. The optimal thresholds (ie, providing the closest mean value to the manual method) were FWHM30% and 3SD for the TIS measurement and FWHM45% and 6SD for the CIS measurement (paired t-test; all P > 0.05). The best reproducibility was obtained using FWHM. For TIS measurement in the acute MI group, intra-/interobserver agreements, from Bland-Altman analysis, with FWHM30%, 3SD, and manual were -0.02 ± 7.74%/-0.74 ± 5.52%, 0.31 ± 9.78%/2.96 ± 16.62% and -2.12 ± 8.86%/0.18 ± 16.12, respectively; in the chronic MI group, the corresponding values were 0.23 ± 3.5%/-2.28 ± 15.06, -0.29 ± 10.46%/3.12 ± 13.06% and 1.68 ± 6.52%/-2.88 ± 9.62%, respectively. A similar trend for reproducibility was obtained for CIS measurement. However, semiautomated methods produced inconsistent results (variabilities of 24-46%) compared to manual delineation.
The FWHM technique was the most reproducible method for infarct sizing both in acute and chronic MI. However, both FWHM and n-SD methods showed limited accuracy compared to manual delineation. J. Magn. Reson. Imaging 2016;44:1206-1217.
比较三种广泛应用于延迟钆增强（LGE）磁共振（MR）图像上心肌梗死（MI）面积测量的方法：手动勾勒法和两种半自动技术（半高宽[FWHM]法和n标准差[SD]法）。
对114例急性心肌梗死后（2 - 4天和6个月）患者的3T相敏反转恢复（PSIR）LGE图像，由两名独立观察者进行分析，以确定梗死总面积和梗死核心面积（TIS/CIS）。手动勾勒法作为参考，用于在多个阈值下确定半自动方法的最佳阈值。重复性和准确性以总体偏差±95%一致性界限表示。
急性心肌梗死组手动测量的平均梗死面积，梗死总面积/梗死核心面积分别为39.0%/24.4%；慢性心肌梗死组为29.7%/17.3%。TIS测量的最佳阈值（即与手动方法均值最接近）为FWHM30%和3SD，CIS测量为FWHM45%和6SD（配对t检验；所有P>0.05）。使用FWHM法获得了最佳重复性。对于急性心肌梗死组的TIS测量，Bland - Altman分析显示，FWHM30%、3SD和手动测量的观察者内/观察者间一致性分别为 - 0.02±7.74%/-0.74±5.52%、0.31±9.
