磁共振颅内动脉斑块成像技术的临床应用

Clinical Use of Magnetic Resonance Plaque Imaging for Intracranial Arteries

目的总结分析颅内动脉斑块成像技术的临床应用价值和局限性。方法回顾性分析北京协和医院2006年12月至2010年9月完成的颅内动脉斑块成像资料(422例)。结果颅内动脉斑块成像技术的成功率97%。颅内主要动脉(大脑中M1段、基底动脉、大脑前动脉M2-3段)的管壁结构能够清晰显示。对大脑中动脉斑块的判断,同一评价者间具有较高的一致性[k=0.96(95%CI=0.88-1.03)]。不同评价者间也具有较高的一致性[k=0.91(95%CI=0.80-1.03)];相对于无症状大脑中动脉狭窄组(35例),症状性狭窄组(26例)有更大的管壁面积(P=0.000)和更大的重塑比(P=0.000),扩张性重塑更多见(P=0.003),缩窄性重塑更少见(P=0.008)。3例大脑中动脉炎性病变表现为均匀强化的环形管壁增厚。结论磁共振斑块成像技术对颅内动脉狭窄的诊断有帮助,但作为一项新技术,尚存在成像范围有限、分辨率较低等局限性。

Objective To summarize the value and limitations of magnetic resonance （MR） plaque imaging for intracranial arteries. Method The data of MR plaque imaging of intracranial arteries in 422 patients performed in Peking Union Medical College Hospital from December 2006 to September 2010 were analyzed retrospectively. Results The success rate for MR plaque imaging of intracranial arteries was 97%. MR plaque imaging clearly displayed the wall structure of the arteries trunk （ M1 segment of middle cerebral arteries, M2-3 segment of anterior cerebral arteries, and basilar arteries）. Good inter-observer （k =0. 91, 95% CI = 0. 80-1.03 ） and intra-observer reproducibility （k = 0.96, 95% CI = 0. 88-1.03 ） was observed in the evalua- tion of middle cerebral arteries＇ atherosclerosis. The wall features had significant difference between symptom- atic and asymptomatic intracranial arteries＇ stenosis; compared with asymptomatic middle cerebral artery stenosis （35 cases）, symptomatic middle cerebral artery stenosis （26 cases） had a significantly larger wall area （P = 0. 000）, greater remodeling ratio （ P = 0. 000 ）, higher prevalence of expansive remodeling （ outward expansion of the vessel wall） （ P = 0.003 ）, and lower prevalence of constrictive remodeling （ P = 0. 008 ）. Arteritis of middle cerebral artery （3 cases） showed circular wall-thicking with apparent gadolinium-diethylene triamine pentaacetic acid-biotin enhancement. Conclusion The MR plaque imaging is helpful in the evaluation of intracranial arteries stenosis, although it still has the limitations such as short scan range and low resolution.