Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität Zu Berlin, ECRC Experimental and Clinical Research Center, Lindenberger Weg 80, 13125, Berlin, Germany.
Working Group On Cardiovascular Magnetic Resonance, Experimental and Clinical Research Center, a joint cooperation between Charité Medical Faculty and the Max-Delbrück Center for Molecular Medicine, Lindenberger Weg 80, 13125, Berlin, Germany.
J Cardiovasc Magn Reson. 2023 Aug 14;25(1):47. doi: 10.1186/s12968-023-00954-9.
Parametric mapping sequences in cardiovascular magnetic resonance (CMR) allow for non-invasive myocardial tissue characterization. However quantitative myocardial mapping is still limited by the need for local reference values. Confounders, such as field strength, vendors and sequences, make intersite comparisons challenging. This exploratory study aims to assess whether multi-site studies that control confounding factors provide first insights whether parametric mapping values are within pre-defined tolerance ranges across scanners and sites.
A cohort of 20 healthy travelling volunteers was prospectively scanned at three sites with a 3 T scanner from the same vendor using the same scanning protocol and acquisition scheme. A Modified Look-Locker inversion recovery sequence (MOLLI) for T1 and a fast low-angle shot sequence (FLASH) for T2 were used. At one site a scan-rescan was performed to assess the intra-scanner reproducibility. All acquired T1- and T2-mappings were analyzed in a core laboratory using the same post-processing approach and software.
After exclusion of one volunteer due to an accidentally diagnosed cardiac disease, T1- and T2-maps of 19 volunteers showed no significant differences between the 3 T sites (mean ± SD [95% confidence interval] for global T1 in ms: site I: 1207 ± 32 [1192-1222]; site II: 1207 ± 40 [1184-1225]; site III: 1219 ± 26 [1207-1232]; p = 0.067; for global T2 in ms: site I: 40 ± 2 [39-41]; site II: 40 ± 1 [39-41]; site III 39 ± 2 [39-41]; p = 0.543).
Parametric mapping results displayed initial hints at a sufficient similarity between sites when confounders, such as field strength, vendor diversity, acquisition schemes and post-processing analysis are harmonized. This finding needs to be confirmed in a powered clinical trial. Trial registration ISRCTN14627679 (retrospectively registered).
心血管磁共振（CMR）中的参数映射序列可实现无创心肌组织特征描述。然而，定量心肌映射仍然受到需要局部参考值的限制。混杂因素，如场强、供应商和序列，使得站点间的比较具有挑战性。这项探索性研究旨在评估在控制混杂因素的多站点研究中，参数映射值是否在扫描仪和站点之间的预定义容差范围内，是否能提供初步的见解。
一项前瞻性研究纳入了 20 名健康旅行志愿者，他们在三个站点使用相同的供应商的 3T 扫描仪，使用相同的扫描方案和采集方案进行扫描。采用改良 Look-Locker 反转恢复序列（MOLLI）进行 T1 测量，快速低角度发射序列（FLASH）进行 T2 测量。在一个站点进行了扫描-再扫描，以评估扫描仪内的可重复性。使用相同的后处理方法和软件，在一个核心实验室分析所有采集的 T1-和 T2-映射。
排除一名因意外诊断出心脏病的志愿者后，19 名志愿者的 T1-和 T2-图谱在 3T 站点之间没有显著差异（ms 中的全球 T1 的平均值±标准差[95%置信区间]：站点 I：1207±32[1192-1222]；站点 II：1207±40[1184-1225]；站点 III：1219±26[1207-1232]；p=0.067；ms 中的全球 T2 的平均值±标准差[95%置信区间]：站点 I：40±2[39-41]；站点 II：40±1[39-41]；站点 III：39±2[39-41]；p=0.543）。
当混杂因素（如场强、供应商多样性、采集方案和后处理分析）得到协调时，参数映射结果初步提示各站点之间具有足够的相似性。这一发现需要在一项有影响力的临床试验中得到证实。试验注册 ISRCTN80201142（回顾性注册）。
