Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA.
Systems and Biomedical Engineering Department, University of Cairo, Cairo, Egypt.
J Magn Reson Imaging. 2017 Dec;46(6):1829-1838. doi: 10.1002/jmri.25695. Epub 2017 Mar 16.
To evaluate diagnostic image quality of 3D late gadolinium enhancement (LGE) with high isotropic spatial resolution (∼1.4 mm ) images reconstructed from randomly undersampled k-space using LOw-dimensional-structure Self-learning and Thresholding (LOST).
We prospectively enrolled 270 patients (181 men; 55 ± 14 years) referred for myocardial viability assessment. 3D LGE with isotropic spatial resolution of 1.4 ± 0.1 mm was acquired at 1.5T using a LOST acceleration rate of 3 to 5. In a subset of 121 patients, 3D LGE or phase-sensitive LGE were acquired with parallel imaging with an acceleration rate of 2 for comparison. Two readers evaluated image quality using a scale of 1 (poor) to 4 (excellent) and assessed for scar presence. The McNemar test statistic was used to compare the proportion of detected scar between the two sequences. We assessed the association between image quality and characteristics (age, gender, torso dimension, weight, heart rate), using generalized linear models.
Overall, LGE detection proportions for 3D LGE with LOST were similar between readers 1 and 2 (16.30% vs. 18.15%). For image quality, readers gave 85.9% and 80.0%, respectively, for images categorized as good or excellent. Overall proportion of scar presence was not statistically different from conventional 3D LGE (28% vs. 33% [P = 0.17] for reader 1 and 26% vs. 31% [P = 0.37] for reader 2). Increasing subject heart rate was associated with lower image quality (estimated slope = -0.009 (P = 0.001)).
High-resolution 3D LGE with LOST yields good to excellent image quality in >80% of patients and identifies patients with LV scar at the same rate as conventional 3D LGE.
2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2017;46:1829-1838.
利用低维结构自学习和阈值（LOST）技术从随机欠采样的 k 空间重建具有高各向同性空间分辨率（约 1.4mm）的 3D 晚期钆增强（LGE）图像，评估其诊断图像质量。
前瞻性纳入 270 例（男 181 例；55±14 岁）因心肌存活评估而行 3D LGE 检查的患者。在 1.5T 扫描仪上使用 LOST 加速率为 3 至 5 进行各向同性空间分辨率为 1.4±0.1mm 的 3D LGE 采集。在 121 例患者的亚组中，采用并行成像加速率为 2 进行 3D LGE 或相位敏感 LGE 采集，用于比较。两位观察者采用 1（差）至 4（优）的评分标准评估图像质量并评估瘢痕存在情况。采用 McNemar 检验比较两种序列检测到的瘢痕比例。我们使用广义线性模型评估图像质量与特征（年龄、性别、躯干尺寸、体重、心率）之间的相关性。
总体而言，LOST 技术生成的 3D LGE 检测比例在观察者 1 和 2 之间相似（16.30%比 18.15%）。在图像质量方面，观察者 1 和 2 分别将 85.9%和 80.0%的图像归类为良好或优秀。瘢痕存在的总体比例与传统 3D LGE 无统计学差异（观察者 1 为 28%比 33%[P=0.17]，观察者 2 为 26%比 31%[P=0.37]）。受试者心率增加与图像质量降低相关（估计斜率为-0.009[P=0.001]）。
LOST 生成的高分辨率 3D LGE 在>80%的患者中获得良好至优秀的图像质量，并以与传统 3D LGE 相同的比例识别 LV 瘢痕患者。
2 技术功效：阶段 2 J. Magn. Reson. Imaging 2017；46：1829-1838。
