颅脑集成MRI与常规MRI图像质量的对比研究  

Comparative study of image quality between synthetic MRI and conventional MRI

作　　者：郑作锋[1] 张东坡[1] 毛磊[1] 耿艳杰[1] 梁枫[1] 赵洪静 张璐[1] ZHENG Zuofeng;ZHANG Dongpo;MAO Lei;GENG Yanjie;LIANG Feng;ZHAOHongjing;ZHANG Lu(Department of Radiology, Beijing Chuiyangliu Hospital, Beijing, 100022, China)

机构地区：[1]北京市垂杨柳医院放射科,朝阳区北京100022

出　　处：《磁共振成像》2019年第5期361-365,共5页Chinese Journal of Magnetic Resonance Imaging

摘　　要：目的将颅脑集成MRI与常规MRI图像对比分析,观察两种图像对比度、噪声水平、伪影的差异,以及对病变的检出能力是否存在差异。材料与方法回顾性分析2018年4月至2018年11月于我院同时行常规MRI和集成MRI扫描的患者30例。对扫描所得T1FLAIR、T2WI、T2FLAIR图像采用观察与测量相结合的方法进行对比。观察内容包括:灰白质界限、病变边界、图像噪声及图像伪影。图像对比度采取测量计算的方法,选取包括脑灰质、脑白质及脑脊液在内的12个感兴趣区,分别测量其信号强度,并计算脑灰质与脑白质,脑灰质与脑脊液,脑白质与脑脊液的相对对比度。结果 Syn MRI信号强度普遍高于ConMRI(P<0.01);Syn T1FLAIR脑灰质、白质及脑脊液的对比度均高于Con T1FLAIR (P<0.01);Syn T2WI灰白质对比度与Con T2WI比较无明显差异,灰质与脑脊液、白质与脑脊液对比度低于Con T2WI (P<0.01);Syn T2FLAIR灰白质对比度与Con T2FLAIR比较无明显差异,灰质与脑脊液、白质与脑脊液对比度高于Con T2FLAIR (P<0.01)。Syn MRI噪声和伪影水平较Con MRI显著,以Syn T2FLAIR图像明显;Syn MRI对脑白质缺血灶边界的显示优于Con MRI,但对灰白质界限清晰度的显示不及Con MRI。结论集成MRI图像灰白质对比度不低于常规扫描,对病变边界显示优于常规扫描;集成MRI与常规MRI相比图像质量下降;集成MRI图像中T2FLAIR伪影严重,日常工作中可加扫常规T2FLAIR以弥补其不足。Objective: Compare the image quality between Synthetic MRI and conventional MRI of the brain by assessment of image contrast, noise level and artifact, and further investigate the differences of diagnostic quality. Materials and Methods: Retrospectively reviewed 30 patients who had synthetic MRI added to conventional MRI scan from Apr to Nov 2018. Images of T1FLAIR, T2WI, T2FLAIR were compared in two different ways: visual grading scale and measurement. Visual imaging quality were rated in 5 scales according to the 4 criteria: gray and white matter interface, margin of the lesion, noise level and artifact. In each patient, 12 regions of interest were placed in the brain image, which included the gray matter, white matter and cerebral spinal fluid. The image contrasts were calculated and compared from the differences of signal intensities measured from 12 different ROIs. Results: Synthetic T1FLAIR, T2WI and T2FLAIR generally had higher signal intensity than conventional MRI (P<0.01). Synthetic T1FLAIR had higher contrast between gray matter, white matter and cerebral spinal fluid than conventional T1FLAIR (P<0.01). Synthetic T2WI had similar contrast between gray matter and white matter with conventional T2WI (P<0.01), and had lower contrast between gray matter and cerebral spinal fluid (P<0.01) as well as white matter and cerebral spinal fluid (P<0.01). Synthetic T2FLAIR had similar contrast between gray matter and white matter, and had higher contrast between gray matter and cerebral spinal fluid (P<0.01) as well as white matter and cerebral spinal fluid (P<0.01). Synthetic MRI had higher level of noise and artifact, especially on T2FLAIR. The conspicuity of white matter focal cerebral ischemia were higher in the Synthetic T1WI and Synthetic T2WI but the interfaces between gray matter and white matter were less clear in Syn MRI. Conclusions: Synthetic MRI has similar or higher image contrast between gray matter and white matter, and has higher lesion conspicuity than conventional MRI. Synthetic MRI image quality

关 键 词：集成磁共振成像 质量控制 脑 

分 类 号：R445.2[医药卫生—影像医学与核医学] R651.1[医药卫生—诊断学]