高分辨率核磁共振管壁成像技术在头颈动脉闭塞病因诊断中的应用价值

摘要

目的 探讨高分辨率MRI(high-resolution MRI,HR-MRI)在头颈部动脉闭塞患者病因诊断中的价值.方法 前瞻性连续纳入2015年12月至2017年2月首都医科大学宣武医院急性头颈动脉闭塞患者25例,采用32通道头颈联合专用线圈行头颈一体化HR-MRI成像,分析闭塞血管节段局部管壁特征和闭塞中远段腔内血栓信号特征.由2名神经内科医师结合纳入患者的临床病史、实验室检查、影像学检查对闭塞病因进行评价并作为参考标准,比较常规管腔成像技术与常规管腔成像联合HR-MRI在病因分类中的准确率.结果 (1)25例急性头颈动脉闭塞患者均完成HR-MRI检查,共诊断闭塞血管31段,其中常规管腔成像诊断了21段,常规管腔成像+HR-MRI诊断了30段;动脉硬化性闭塞24段(19例),动脉夹层性闭塞4段(4例),动脉炎性闭塞3段(2例).(2)动脉硬化性闭塞患者中,闭塞节段近端管壁均可见偏心性增厚;动脉夹层性闭塞均见典型的双腔征或新月形高信号壁内血肿;血管炎性闭塞血管节段中可见长节段环形增厚及强化.(3)常规管腔成像技术与常规管腔成像联合HR-MRI对病因分类诊断的准确率分别为67.7%(21/31)和 96.8%(30/31),差异有统计学意义(P<0.01).结论 相较于常规管腔成像技术,头颈联合HR-MRI可显示闭塞起始段动脉管壁特征,对判读动脉粥样硬化、动脉夹层和动脉炎性病变等病因具有一定优势.%Objective To discuss the value of high-resolution magnetic resonance imaging (HR-MRI) in the etiological diagnosis of patients with head and neck artery occlusion.Methods From December 2015 to February 2017,25 consecutive patients with acute head and neck artery occlusion in Xuanwu Hospital,Capital Medical University were enrolled prospectively.The 32-channel head-neck combined coils were used to conduct head-neck integrated HR-MRI.The characteristics of proximal vascular wall of the occluded vascular segments and the signal features of thrombi in the middle and distal segments of occlusion were analyzed.The evaluation of the occlusive etiology was performed by two neurologists according to the clinical history,laboratory examinations,and imaging examinations of the patients,and the accuracy of conventional lumen imaging and conventional lumen imaging combined with HR-MRI in etiological classification were compared.Results Twenty-five patients with acute head and neck artery occlusion completed HR-MRI examinations.A total of 31 segments of the occluded vessels were diagnosed,and 21 of these were diagnosed with the conventional luminal imaging,30 were diagnosed with the conventional luminal imaging+HR-MRI,including 24 segments of atherosclerotic occlusion (n=19),4 segments of arterial dissecting occlusion (n=4),and 3 segments of arteritis occlusion (n=2).(2) In patients with atherosclerotic occlusion,the eccentric thickening was observed in the proximal wall of occlusive segment;the typical double-lumen or crescent-shaped hyperintense hematoma were observed in occlusive arterial dissection;long-segment annular thickening and enhancement were observed in the segment of arteritis occlusion.(3) The accuracy of the cause classification diagnosis of conventional luminal imaging and conventional luminal imaging+HR-MRI were 67.7% (21/31) and 96.8% (30/31) respectively (P<0.01).Conclusions Compared with the luminal imaging,the head and neck combined HR-MRI can reveal the arterial wall characteristics of the initial segment of occlusion.It has certain advantages in the interpretation of the causes,such as atherosclerosis,arterial dissection and arteritis.