Li Hao, Li Bo, Huang Wenjian, Dong Li, Zhang Jue
Academy of Advanced Interdisciplinary Studies, Peking University, Beijing, China.
College of Engineering, Peking University, Beijing, China.
Magn Reson Med. 2017 Apr;77(4):1612-1618. doi: 10.1002/mrm.26218. Epub 2016 Mar 28.
To develop and validate a dual-contrast image subtraction (DCIS) strategy for eliminating the flow artifacts in black-blood carotid MRI.
Twelve patients with carotid stenosis and eight healthy volunteers were imaged using the black and gray-blood dual-contrast imaging based on the relaxation-enhanced compressed sensing three-dimensional motion-sensitizing driven equilibrium prepared rapid-gradient-echo (RECS-3D MERGE) sequence. Subtraction of black-blood images (BBIs) and gray-blood images (GBIs), together with a preweighting procedure, was performed to eliminate the residual blood signal in BBIs. A wavelet denoising procedure was applied to offset the noise amplification. In addition to the lumen signal-to-noise ratio (SNR) and wall-lumen contrast-to-noise ratio (CNR), the signal variance ratio (SVR) and contrast variance ratio (CVR) were also used to evaluate the blood suppression efficiency.
By choosing the weighting factor of one, the lumen SNR of DCIS images was approximately 1% of that of the original BBIs, and the CNR showed a 91.4% improvement as compared with the BBIs. The median of the lumen SVR decreased to zero, and the CVR increased to 123% of that of the BBIs.
DCIS is demonstrated to be an effective strategy for sufficiently removing the residual flow signal from black-blood carotid MRI. Magn Reson Med 77:1612-1618, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
开发并验证一种双对比图像减法（DCIS）策略，以消除黑血颈动脉磁共振成像（MRI）中的血流伪影。
对12例颈动脉狭窄患者和8名健康志愿者，采用基于弛豫增强压缩感知三维运动敏感驱动平衡准备快速梯度回波（RECS - 3D MERGE）序列的黑血和灰血双对比成像进行扫描。通过对黑血图像（BBIs）和灰血图像（GBIs）进行减法运算，并结合预加权程序，来消除BBIs中的残留血液信号。应用小波去噪程序来抵消噪声放大。除了管腔信噪比（SNR）和壁 - 腔对比噪声比（CNR）外，还使用信号方差比（SVR）和对比方差比（CVR）来评估血液抑制效率。
通过选择权重因子为1，DCIS图像的管腔SNR约为原始BBIs的1%，与BBIs相比，CNR提高了91.4%。管腔SVR的中位数降至零，CVR增加到BBIs的123%。
DCIS被证明是一种从黑血颈动脉MRI中充分去除残留血流信号的有效策略。《磁共振医学》77:1612 - 1618, 2017。© 2016国际磁共振医学学会。
