摘要
目的：探讨正常人脑及脑梗塞弥散加权平面回波成像（ＤＷＥＰＩ）的特点。材料与方法：２８例健康志愿者及１５例脑梗塞患者均作ＤＷＥＰＩ，分析其表现并计算正常人脑组织、脑梗塞区的表面弥散系数（ＡＤＣ）及相对ＡＤＣ（ｒＡＤＣ）。结果：正常人脑脊液、灰质、顶、额、枕叶白质的ＡＤＣ平均值分别为３．１２、０．８９、０．７１、０．８０、０．８４×１０－３ｍｍ２／ｓ；急性期脑梗塞在ＤＷＩ上表现为高信号，ＡＤＣ值下降为０．５７～０．６２×１０－３ｍｍ２／ｓ，ＤＷＩ对病变的显示明显优于常规Ｔ２ＷＩ；亚急性期和慢性期脑梗塞表现为高或等信号，平均ＡＤＣ值分别为０．７１、１．２７×１０－３ｍｍ２／ｓ，ＤＷＩ所示的高信号范围与常规Ｔ２ＷＩ不完全一致。结论：ＤＷＥＰＴ对脑梗塞的早期诊断及评价起重要的作用。
Objective: To evaluate the diffusion weighted echo planar imaging (DW EPI) features of brain in normal subjects and in patients with cerebral infarction.Materials and Methods:DW EPI was performed in 28 healthy volunteers and 15 patients with cerebral infarction. Apparent diffusion coefficient (ADC) and relative ADC of normal tissues and cerebral infarcts were calculated.Results:In normal subjects, the ADC values of cerebrospinal fluid, gray matter, and parietal, frontal, occipital white matter were 3.12, 0.89, 0.71, 0.80, and 0.84×10 -3 mm 2/s, respectively. Acute infarcts appeared as areas of hyperintensity on DW images, with a decreased ADC of 0.57～0.62×10 -3 mm 2/s. The lesions were more readily shown on DWI than on conventional T 2WI. Subacute and chronic infarcts presented hyperintensity or isointensity on DW images, with an average ADC of 0.71 and 1.27×10 -3 mm 2/s respectively. The areas of hyperintensity on DW images were not fully consistent with that on conventional T 2WI.Conclusion: DW EPI plays an important role in making early diagnosis and evaluation of cerebral infarction.
出处
《临床放射学杂志》
CSCD
北大核心
1999年第3期133-136,共4页
Journal of Clinical Radiology
