Orbach Darren B, Wu Chris, Law Meng, Babb James S, Lee Ray, Padua Abraham, Knopp Edmond A
Department of Radiology, Division of Neuroradiology, NYU Medical Center, New York, New York, USA.
J Magn Reson Imaging. 2006 Jul;24(1):16-24. doi: 10.1002/jmri.20612.
To evaluate signal-to-noise ratio (SNR) and neuroradiologists' subjective assessments of image quality in 3-Tesla (3-T) or phased-array MR systems that are now available for clinical neuroimaging.
Brain MR images of six normal volunteers were obtained on each of three scanners: a 1.5-T single-channel system, a 12-channel, phased-array system, and a 3-T single-channel system. Additionally, clinically optimized images acquired from 28 patients who underwent imaging in more than one of these systems were analyzed. SNRs were measured and image quality and artifact conspicuity were graded by two blinded readers.
The phased-array system produced higher SNR than either the 1.5-T or the 3-T single-channel systems, and in no instance was it outperformed. Both blinded readers judged the phased-array images to be of higher quality than those produced by the single-channel systems, with significantly less artifact. The 3-T magnet produced images with high SNR, but with increased artifact conspicuity. The phased-array system markedly decreased acquisition times without introduction of artifacts.
Both quantitatively and qualitatively, the phased-array system provided image quality superior to that of the 1.5-T and 3-T single-channel systems.
评估目前可用于临床神经成像的3特斯拉(3-T)或相控阵磁共振(MR)系统中的信噪比(SNR)以及神经放射科医生对图像质量的主观评估。
在三台扫描仪上分别获取了六名正常志愿者的脑部MR图像:一台1.5-T单通道系统、一台12通道相控阵系统和一台3-T单通道系统。此外,还分析了从28名在上述多个系统中接受成像检查的患者身上获取的临床优化图像。测量了SNR,并由两名不知情的阅片者对图像质量和伪影清晰度进行评分。
相控阵系统产生的SNR高于1.5-T或3-T单通道系统,且在任何情况下都未被超越。两名不知情的阅片者均判断相控阵图像的质量高于单通道系统产生的图像,伪影明显更少。3-T磁体产生的图像具有较高的SNR,但伪影清晰度增加。相控阵系统显著缩短了采集时间,且未引入伪影。
在定量和定性方面,相控阵系统提供的图像质量均优于1.5-T和3-T单通道系统。