Dalmer Antonia, Meinel Felix G, Böttcher Benjamin, Manzke Mathias, Lorbeer Roberto, Weber Marc-André, Baeßler Bettina, Klemenz Ann-Christin
Institute of Diagnostic and Interventional Radiology, Pediatric Radiology and Neuroradiology, University Medical Centre Rostock, Rostock, Germany.
Department of Radiology, Ludwig-Maximilian University, Munich, Germany.
Quant Imaging Med Surg. 2024 Jan 3;14(1):20-30. doi: 10.21037/qims-23-943. Epub 2023 Nov 14.
Myocardial mapping techniques can be used to quantitatively assess alterations in myocardial tissue properties. This study aims to evaluate the influence of spatial resolution on quantitative results and reproducibility of native myocardial T1 mapping in cardiac magnetic resonance imaging (MRI).
In this cross-sectional study with prospective data collection between October 2019 and February 2020, 50 healthy adults underwent two identical cardiac MRI examinations in the radiology department on the same day. T1 mapping was performed using a MOLLI 5(3)3 sequence with higher (1.4 mm × 1.4 mm) and lower (1.9 mm × 1.9 mm) in-plane spatial resolution. Global quantitative results of T1 mapping were compared between high-resolution and low-resolution acquisitions using paired -test. Intra-class correlation coefficient (ICC) and Bland-Altman statistics (absolute and percentage differences as means ± SD) were used for assessing test-retest reproducibility.
There was no significant difference between global quantitative results acquired with high low-resolution T1 mapping. The reproducibility of global T1 values was good for high-resolution (ICC: 0.88) and excellent for low-resolution T1 mapping (ICC: 0.95, P=0.003). In subgroup analyses, inferior test-retest reproducibility was observed for high spatial resolution in women compared to low spatial resolution (ICC: 0.71 0.91, P=0.001) and heart rates >77 bpm (ICC: 0.53 0.88, P=0.004). Apical segments had higher T1 values and variability compared to other segments. Regional T1 values for basal (ICC: 0.81 0.89, P=0.023) and apical slices (ICC: 0.86 0.92, P=0.024) showed significantly higher reproducibility in low-resolution compared to high-resolution acquisitions but without differences for midventricular slice (ICC: 0.91 0.92, P=0.402).
Based on our data, we recommend a spatial resolution on the order of 1.9 mm × 1.9 mm for native myocardial T1 mapping using a MOLLI 5(3)3 sequence at 1.5 T particularly in individuals with higher heart rates and women.
心肌成像技术可用于定量评估心肌组织特性的改变。本研究旨在评估空间分辨率对心脏磁共振成像（MRI）中天然心肌T1成像定量结果和可重复性的影响。
在这项2019年10月至2020年2月前瞻性收集数据的横断面研究中，50名健康成年人于同一天在放射科接受了两次相同的心脏MRI检查。使用MOLLI 5(3)3序列进行T1成像，其平面内空间分辨率较高（1.4 mm×1.4 mm）和较低（1.9 mm×1.9 mm）。使用配对t检验比较高分辨率和低分辨率采集的T1成像的整体定量结果。组内相关系数（ICC）和Bland-Altman统计量（绝对差异和百分比差异，以均值±标准差表示）用于评估重测可重复性。
高分辨率和低分辨率T1成像获得的整体定量结果之间无显著差异。整体T1值的可重复性在高分辨率时良好（ICC：0.88），在低分辨率T1成像时优秀（ICC：0.95，P = 0.003）。在亚组分析中，与低空间分辨率相比，女性高空间分辨率的重测可重复性较差（ICC：0.71对0.91，P = 0.001），心率>77次/分时也是如此（ICC：0.53对0.88，P = 0.004）。与其他节段相比，心尖节段的T1值和变异性更高。与高分辨率采集相比，低分辨率下基底段（ICC：0.81对0.89，P = 0.023）和心尖切片（ICC：0.86对0.92，P = 0.024）的区域T1值显示出显著更高的可重复性，但心室中段切片无差异（ICC：0.91对0.92，P = 0.402）。
根据我们的数据，我们建议在1.5 T时使用MOLLI 5(3)3序列进行天然心肌T1成像时，空间分辨率约为1.9 mm×1.9 mm，特别是对于心率较高的个体和女性。
