Three-dimensional self-gated cardiac MR imaging for the evaluation of myocardial infarction in mouse model on a 3T clinical MR system

Purpose: To develop and assess a three-dimensional (3D) self-gated technique for the evaluation of myocardial infarction (MI) in mouse model without the use of external electrocardiogram (ECG) trigger and respiratory motion sensor on a 3T clinical MR system. Methods: A 3D T1-weighted GRE sequence with stack-of-stars sampling trajectories was developed and performed on six mice with MIs that were injected with a gadolinium-based contrast agent at a 3T clinical MR system. Respiratory and cardiac self-gating signals were derived from the Cartesian mapping of the k-space center along the partition encoding direction by bandpass filtering in image domain. The data were then realigned according to the predetermined self-gating signals for the following image reconstruction. In order to accelerate the data acquisition, image reconstruction was based on compressed sensing (CS) theory by exploiting temporal sparsity of the reconstructed images. In addition, images were also reconstructed from ...研究目的：开发并评估一项三维（3D）自门控技术，用于在3T临床磁共振（magnetic resonance, MR）系统上，无需外接心电图（electrocardiogram, ECG）触发器与呼吸运动传感器的前提下，评估小鼠模型中的心肌梗死（myocardial infarction, MI）。 研究方法：在3T临床MR系统上，对6只注射了钆类造影剂的心肌梗死模型小鼠，开发并实施了采用星状堆叠采样轨迹的三维T1加权梯度回波（gradient recalled echo, GRE）序列。通过在图像域对沿分层编码方向的k空间中心进行笛卡尔映射并实施带通滤波，提取呼吸与心脏自门控信号。随后根据预先获取的自门控信号对数据进行重对齐，以用于后续图像重建。为加速数据采集，本研究基于压缩感知（compressed sensing, CS）理论，利用重建图像的时间稀疏性完成图像重建。此外，图像还可从……