Rashid Shams, Rapacchi Stanislas, Shivkumar Kalyanam, Plotnik Adam, Finn J Paul, Hu Peng
Department of Radiological Sciences, David Geffen School of Medicine, University of California, Los Angeles, California, USA.
UCLA Cardiac Arrhythmia Center, David Geffen School of Medicine, University of California, Los Angeles, California, USA.
Magn Reson Med. 2016 Feb;75(2):572-84. doi: 10.1002/mrm.25601. Epub 2015 Mar 13.
To study the effects of cardiac devices on three-dimensional (3D) late gadolinium enhancement (LGE) MRI and to develop a 3D LGE protocol for implantable cardioverter defibrillator (ICD) patients with reduced image artifacts.
The 3D LGE sequence was modified by implementing a wideband inversion pulse, which reduces hyperintensity artifacts, and by increasing bandwidth of the excitation pulse. The modified wideband 3D LGE sequence was tested in phantoms and evaluated in six volunteers and five patients with ICDs.
Phantom and in vivo studies results demonstrated extended signal void and ripple artifacts in 3D LGE that were associated with ICDs. The reason for these artifacts was slab profile distortion and the subsequent aliasing in the slice-encoding direction. The modified wideband 3D LGE provided significantly reduced ripple artifacts than 3D LGE with wideband inversion only. Comparison of 3D and 2D LGE images demonstrated improved spatial resolution of the heart using 3D LGE.
Increased bandwidth of the inversion and excitation pulses can significantly reduce image artifacts associated with ICDs. Our modified wideband 3D LGE protocol can be readily used for imaging patients with ICDs given appropriate safety guidelines are followed.
研究心脏设备对三维（3D）延迟钆增强（LGE）磁共振成像（MRI）的影响，并为图像伪影减少的植入式心脏复律除颤器（ICD）患者制定一种3D LGE方案。
通过实施宽带反转脉冲（可减少高强度伪影）和增加激发脉冲的带宽来修改3D LGE序列。修改后的宽带3D LGE序列在模型中进行测试，并在6名志愿者和5名ICD患者中进行评估。
模型和体内研究结果表明，3D LGE中与ICD相关的信号空洞和波纹伪影有所增加。这些伪影的原因是层块轮廓失真以及切片编码方向上随后出现的混叠。与仅采用宽带反转的3D LGE相比，修改后的宽带3D LGE显著减少了波纹伪影。3D和2D LGE图像的比较表明，使用3D LGE可提高心脏的空间分辨率。
增加反转和激发脉冲的带宽可显著减少与ICD相关的图像伪影。在遵循适当安全指南的情况下，我们修改后的宽带3D LGE方案可轻松用于ICD患者的成像。
