老年人颈动脉粥样硬化的高分辨率MRI研究

Study on high resolusion MRI in carotid atherosclerotic plaque in elderly patients

目的 探讨高分辨率磁共振成像（MRI）在老年颈动脉粥样硬化斑块检测及评价中的应用价值。方法 采用双翻转脉冲（DIR）-T1WI、快速自选回波（FSE）-T2WI和三维时间飞跃法（3D—TOF）序列对16例老年患者行颈动脉高分辨率MRI成像，评价有无硬化斑块并对其分型。结果 13例29处可见粥样硬化改变，包括颈总动脉4处，颈动脉分叉17处，颈内动脉7处和颈外动脉l处。其中Ⅲ型12个、Ⅳ-Ⅴ型9个、Ⅵ型3个、Ⅶ型5个。硬化斑块在T1WI、T2WI上表现为管壁不规则增厚，伴有或不伴有局限性的新月形或半月形信号灶突入管腔，TOF上表现为管腔内高信号血流中见低信号充盈缺损。3例颈内动脉有明显狭窄（狭窄〉70％）。比较3个序列。DIR—T1WI在显示粥样硬化斑块方面优于其它序列。结论 MRI能清晰显示颈动脉粥样硬化斑块，并能根据其信号变化判断其组成，为临床选择治疗方案及估计预后提供有力的帮助。

Objective To evaluate the application value of high resolution MRI in the detection of carotid arteriosclerosis and in characterizing the morphology of individual atheroselerotic carotid plaques in old patients, Methods Carotid arteries MRI was performed in 16 elderly patients, DIR-T1WI, FSE-T2WI ancl 3D-TOF sequence were used in the MRI measurement for all patients. Results Of 16 patients, 13 showed changes of carotid arteriosclerosis on 29 locations,including 4 in the common carotid artery, 17 in carotid artery bifurcation, 7 in internal carotid artery, and 1 in external carotid artery. The MRI classification included 12 cases of type Ⅲ ,9 of type Ⅳ-Ⅴ ,3 of type Ⅵ and 5 of type Ⅶ, All plaques showed defects in the high intensity of vessel lumen on TOF sequence, and presented moderate, low and （or） high intensity on DIR-T1 WI and T2WI. Conclusions MRI is a powerful noninvasive imaging tool with high spatial resolution in determining atherosclerotic plaque volume and tissue components. This imaging technique is useful in establishing treatment plan and estimating the therapeutic efficacy and outcome of the patients.