Free-breathing myocardial T1 mapping using inversion-recovery radial FLASH and motion-resolved model-based reconstruction.
Free-breathing myocardial T1 mapping using inversion-recovery radial FLASH and motion-resolved model-based reconstruction.
复制标题
使用反转恢复径向 FLASH 和基于运动分辨模型的重建进行自由呼吸心肌 T1 映射。
DOI：
10.1002/mrm.29521
复制
发表时间：
2023
影响因子：
3.3
通讯作者：
Uecker,Martin
中科院分区：
文献类型：
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作者：
Wang,Xiaoqing;Rosenzweig,Sebastian;Roeloffs,Volkert;Blumenthal,Moritz;Scholand,Nick;Tan,Zhengguo;Holme,HChristianM;Unterberg-Buchwald,Christina;Hinkel,Rabea;Uecker,Martin
目的利用反转恢复(IR)径向快速小角度激发(Flash)技术和基于无标定运动分辨模型的重建技术，建立自由呼吸心肌T1$1标测技术。首先，为了减少两次反演之间的等待时间，导出了一个解析公式，该公式考虑了T1${\mathm{T}}_1$$的不完全恢复，从而实现了T1$${\mathm{T}}_1$$的精确计算。其次，使用自适应奇异谱分析(SSA-Fary)技术从对比度变化采集的k空间中心估计呼吸运动信号。第三，使用基于运动分辨模型的重建方法，直接从分类的k空间数据估计参数和线圈敏感度图。因此，除了空间稀疏性约束外，时空全变分还可以直接应用于参数映射。结果与红外自旋回波参考模型相比，模型结果证实了良好的T1$$\mathm{T}}_1$$准确性，使用新的校正方法将等待时间从5个S减少到1个S。与仅基于空间正则化的重建相比，基于运动分辨模型的重建进一步提高了T1$${\mathm{T}}_1$$的精度。体内研究表明，除了使用改进的SSA-Fary可以估计出可靠的呼吸运动信号外，动态心肌T1${mathm{T}}_1$$映射可以在2分钟内获得，且具有良好的精度和重复性。结论运动分辨心肌T1$\mathm{T}}_1$$映射结合反转-恢复径向闪光、自选通和基于无标定运动分辨模型的重建，可以在自由呼吸过程中获得具有良好精度、精密度和重复性的运动分辨心肌T1$$映射。
PurposeTo develop a free‐breathing myocardial T1$$ {\mathrm{T}}_1 $$ mapping technique using inversion‐recovery (IR) radial fast low‐angle shot (FLASH) and calibrationless motion‐resolved model‐based reconstruction.MethodsFree‐running (free‐breathing, retrospective cardiac gating) IR radial FLASH is used for data acquisition at 3T. First, to reduce the waiting time between inversions, an analytical formula is derived that takes the incomplete T1$$ {\mathrm{T}}_1 $$ recovery into account for an accurate T1$$ {\mathrm{T}}_1 $$ calculation. Second, the respiratory motion signal is estimated from the k‐space center of the contrast varying acquisition using an adapted singular spectrum analysis (SSA‐FARY) technique. Third, a motion‐resolved model‐based reconstruction is used to estimate both parameter and coil sensitivity maps directly from the sorted k‐space data. Thus, spatiotemporal total variation, in addition to the spatial sparsity constraints, can be directly applied to the parameter maps. Validations are performed on an experimental phantom, 11 human subjects, and a young landrace pig with myocardial infarction.ResultsIn comparison to an IR spin‐echo reference, phantom results confirm good T1$$ {\mathrm{T}}_1 $$ accuracy, when reducing the waiting time from 5 s to 1 s using the new correction. The motion‐resolved model‐based reconstruction further improves T1$$ {\mathrm{T}}_1 $$ precision compared to the spatial regularization‐only reconstruction. Aside from showing that a reliable respiratory motion signal can be estimated using modified SSA‐FARY, in vivo studies demonstrate that dynamic myocardial T1$$ {\mathrm{T}}_1 $$ maps can be obtained within 2 min with good precision and repeatability.ConclusionMotion‐resolved myocardial T1$$ {\mathrm{T}}_1 $$ mapping during free‐breathing with good accuracy, precision and repeatability can be achieved by combining inversion‐recovery radial FLASH, self‐gating and a calibrationless motion‐resolved model‐based reconstruction.