Gao Juan, Gong Yiwen, Emu Yixin, Chen Zhuo, Chen Haiyang, Yang Fan, Ding Zekang, Hua Sha, Jin Wei, Hu Chenxi
School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China.
Department of Cardiovascular Medicine, Heart Failure Center, Ruijin Hospital and Ruijin Hospital Lu Wan Branch, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
J Magn Reson Imaging. 2025 Mar;61(3):1388-1401. doi: 10.1002/jmri.29564. Epub 2024 Aug 14.
Cardiac T1 mapping is valuable for evaluating myocardial fibrosis, yet its resolution and acquisition efficiency are limited, potentially obscuring visualization of small pathologies.
To develop a technique for high-resolution cardiac T1 mapping with a less-than-100-millisecond acquisition window based on radial MOdified Look-Locker Inversion recovery (MOLLI) and a calibrationless space-contrast-coil locally low-rank tensor (SCC-LLRT) constrained reconstruction.
Prospective.
SUBJECTS/PHANTOM: Sixteen healthy subjects (age 25 ± 3 years, 44% females) and 12 patients with suspected cardiomyopathy (age 57 ± 15 years, 42% females), NiCl2-agar phantom.
FIELD STRENGTH/SEQUENCE: 3-T, standard MOLLI, radial MOLLI, inversion-recovery spin-echo, late gadolinium enhancement.
SCC-LLRT was compared to a conventional locally low-rank (LLR) method through simulations using Normalized Root-Mean-Square Error (NRMSE) and Structural Similarity Index Measure (SSIM). Radial MOLLI was compared to standard MOLLI across phantom, healthy subjects, and patients. Three independent readers subjectively evaluated the quality of T1 maps using a 5-point scale (5 = best).
Paired t-test, Wilcoxon signed-rank test, intraclass correlation coefficient analysis, linear regression, Bland-Altman analysis. P < 0.05 was considered statistically significant.
In simulations, SCC-LLRT demonstrated a significant improvement in NRMSE and SSIM compared to LLR. In phantom, both radial MOLLI and standard MOLLI provided consistent T1 estimates across different heart rates. In healthy subjects, radial MOLLI exhibited a significantly lower mean T1 (1115 ± 39 msec vs. 1155 ± 36 msec), similar T1 SD (74 ± 14 msec vs. 67 ± 23 msec, P = 0.20), and similar T1 reproducibility (28 ± 18 msec vs. 22 ± 15 msec, P = 0.34) compared to standard MOLLI. In patients, the proposed method significantly improved the sharpness of myocardial boundaries (4.50 ± 0.65 vs. 3.25 ± 0.43), the conspicuity of papillary muscles and fine structures (4.33 ± 0.74 vs. 3.33 ± 0.47), and artifacts (4.75 ± 0.43 vs. 3.83 ± 0.55). The reconstruction time for a single slice was 5.2 hours.
The proposed method enables high-resolution cardiac T1 mapping with a short acquisition window and improved image quality.
1 TECHNICAL EFFICACY: Stage 1.
心脏T1映射对于评估心肌纤维化很有价值，但其分辨率和采集效率有限，可能会使小病变的可视化变得模糊。
基于径向改良Look-Locker反转恢复（MOLLI）和无校准空间对比线圈局部低秩张量（SCC-LLRT）约束重建，开发一种采集窗口小于100毫秒的高分辨率心脏T1映射技术。
前瞻性研究。
受试者/体模：16名健康受试者（年龄25±3岁，44%为女性）和12名疑似心肌病患者（年龄57±15岁，42%为女性），NiCl2-琼脂体模。
场强/序列：3-T，标准MOLLI、径向MOLLI、反转恢复自旋回波、延迟钆增强。
通过使用归一化均方根误差（NRMSE）和结构相似性指数测量（SSIM）的模拟，将SCC-LLRT与传统局部低秩（LLR）方法进行比较。在体模、健康受试者和患者中，将径向MOLLI与标准MOLLI进行比较。三名独立读者使用5分制（5=最佳）主观评估T1图的质量。
配对t检验、Wilcoxon符号秩检验、组内相关系数分析、线性回归、Bland-Altman分析。P<0.05被认为具有统计学意义。
在模拟中，与LLR相比，SCC-LLRT在NRMSE和SSIM方面有显著改善。在体模中，径向MOLLI和标准MOLLI在不同心率下均提供了一致的T1估计值。在健康受试者中，与标准MOLLI相比，径向MOLLI的平均T1显著更低（1115±39毫秒对1155±36毫秒），T1标准差相似（74±14毫秒对67±23毫秒，P=0.20），T1再现性相似（28±18毫秒对22±15毫秒，P=0.34）。在患者中，所提出的方法显著提高了心肌边界的清晰度（4.50±0.65对3.25±0.43）、乳头肌和精细结构的可见性（4.33±0.74对3.33±0.47）以及伪影（4.75±0.43对3.83±0.55）。单一层面的重建时间为5.2小时。
所提出的方法能够实现具有短采集窗口和改进图像质量的高分辨率心脏T1映射。
1 技术疗效：1期。
