增强FLAIR图像上正常颅内强化结构分析

目的探讨正常颅内结构在液体衰减反转恢复(FLAIR)增强图像上的强化表现。方法100例常规头颅MRI显示正常者,行头颅增强前后FLAIR成像,比较图像,确定各颅内结构有无强化,并与T1WI增强图像进行比较。结果脉络丛、垂体柄和第四脑室外侧隐窝静脉的强化常见,出现率分别为98%、78%和59%。硬脑膜强化见于18%的受试者,其长度平均为24.2 mm,最常见于双侧颞叶岛盖;皮层血管强化的发生率为12%,常见于顶部层面,强化的硬脑膜和皮层血管在平扫FLAIR上多表现为等信号,强化后呈稍高信号。静脉窦和静脉窦壁的强化率分别为15%和7%,松果体强化发生率为7%。所有强化结构在增强T1WI上均有强化,且强化程度更明显。结论脑增强FLAIR图像上正常结构强化有其特定的表现,增强FLAIR在脑膜疾病、后颅窝及邻近脑沟的病灶显示方面具有潜在优势。

Analysis of normally enhancing intracranial structure on contrast-enhanced fluid-attenuated inversion-recovery MR imaging

Objective To investigate the appearance of normally enhancing intracranial structure on contrast-enhanced fluid-attenuated inversion-recovery(FLAIR) MR imaging.Methods Pre-and post-enhanced FLAIR imaging of the brain were performed in 100 normal persons,which were contributed to determine whether normal intracranial structure had enhancement and which were compared with post-enhanced T1WI.Results Choroid plexus,pituitary stalk and vein of lateral recess of fourth ventricle were the most common enhancing structure,the rate were 98%,78% and 59% respectively.The enhancement rate of dura matter was 18%,the average length of which was 24.2 mm,which were often located in bilateral temporal operculum;the enhanc rate of cortical veins was 12%,and which were often located in supra slice,enhancing dura and cortical vein almost were iso-signal on pre-enhanced FLAIR images and slightly hyper-signal on post-enhanced FLAIR images.The enhancing rate of dural sinuses and sinus mural were 15% and 7% respectively,the enhancement rate of pineal gland was 7%.All enhancing intracranial structure on post-enhanced FLAIR images had more obviously enhancement on post-enhanced T1WI.Conclusion The enhancement of normal intracranial structure have specified appearance on post-enhanced FLAIR imaging,which has potential superiority in discovering meningeal disease and lesions which located in posterior cranial fossa or closed to sulci.