Song Hee Kwon, Yan Lirong, Smith Robert X, Xue Yiqun, Rapacchi Stanislas, Srinivasan Subashini, Ennis Daniel B, Hu Peng, Pouratian Nader, Wang Danny J J
Department of Radiology, University of Pennsylvania Medical Center, Philadelphia, Pennsylvania, USA.
Magn Reson Med. 2014 Dec;72(6):1541-51. doi: 10.1002/mrm.25057. Epub 2013 Dec 12.
To explore the feasibility of 2D and 3D golden-angle radial acquisition strategies in conjunction with k-space weighted image contrast (KWIC) temporal filtering to achieve noncontrast enhanced dynamic MRA (dMRA) with high spatial resolution, low streaking artifacts and high temporal fidelity.
Simulations and in vivo examinations in eight normal volunteers and an arteriovenous malformation patient were carried out. Both 2D and 3D golden angle radial sequences, preceded by spin tagging, were used for dMRA of the brain. The radial dMRA data were temporally filtered using the KWIC strategy and compared with matched standard Cartesian techniques.
The 2D and 3D dynamic MRA image series acquired with the proposed radial techniques demonstrated excellent image quality without discernible temporal blurring compared with standard Cartesian based approaches. The image quality of radial dMRA was equivalent to or higher than that of Cartesian dMRA by visual inspection. A reduction factor of up to 10 and 3 in scan time was achieved for 2D and 3D radial dMRA compared with the Cartesian-based counterparts.
The proposed 2D and 3D radial dMRA techniques demonstrated image quality comparable or even superior to those obtained with standard Cartesian methods, but within a fraction of the scan time.
探讨二维和三维黄金角径向采集策略结合k空间加权图像对比度(KWIC)时间滤波,以实现具有高空间分辨率、低条纹伪影和高时间保真度的非对比增强动态磁共振血管造影(dMRA)的可行性。
对8名正常志愿者和1名动静脉畸形患者进行了模拟和体内检查。在自旋标记之前,二维和三维黄金角径向序列均用于脑部dMRA。使用KWIC策略对径向dMRA数据进行时间滤波,并与匹配的标准笛卡尔技术进行比较。
与基于标准笛卡尔的方法相比,采用所提出的径向技术采集的二维和三维动态MRA图像序列显示出优异的图像质量,没有明显的时间模糊。通过视觉检查,径向dMRA的图像质量等同于或高于笛卡尔dMRA。与基于笛卡尔的dMRA相比,二维和三维径向dMRA的扫描时间分别减少了高达10倍和3倍。
所提出的二维和三维径向dMRA技术显示出的图像质量与标准笛卡尔方法相当甚至更优,但扫描时间仅为其几分之一。