（优质课件）颅内动脉斑块高分辨成像.ppt

1、,高分辨核磁,1,各个序列,图像处理软件,2,历史沿革,1995年,最初,髂动脉粥样 硬化斑块,第一项关于颅内血管壁成像的研究进展,1990年,Edelman等分析了颈动脉粥样硬化性疾病的黑血和亮血成像技术斑块组成特点及MRI信号表现，对动脉粥样硬化的评价不再仅局限于动脉狭窄。,2003年,Naghavi等介绍了主要针对颈动脉不稳定斑块的模型，证明特定的斑块成分可以导致患者的临床症状进展，结局表现为血栓形成和栓塞,2009年,neurology HRMRI可以区分 颅内动脉不同的病变,3,磁共振斑块成像在中国,4,成像技术,“亮血”技术,用3D时间飞跃法成像 (three dimention

2、time of flight,3D-TOF) 优点：采集时间短,5,成像技术,“黑血”技术：通过各种方法抑制流动血液信号，使管腔内血液流动信号消失，以便更好的衬托出管壁软组织（动脉粥样硬化斑块）的信号，该技术是斑块成像技术的核心。,T1序列（T1-weighted imaging，T1WI）、 T2序列（T 2-weighted imaging，T2WI） 质子序列（proton density weighted imaging，PDWI） 磁化准备快速梯度回波序列（magnetization prepared rapid gradientecho，MP-RAGE） T1强化序列（T1 con

3、trast enhanced weighted imaging，T1+C）,6,颅内动脉粥样硬化,动脉夹层,Moyamoya病,动脉瘤,脑小血管病,静脉系统血栓,7,应用目的,判定缺血性卒中发病机制,8,应用目的,除外非动脉粥样硬化性狭窄,9,应用目的,分析斑块特点（稳定 OR 不稳定） 斑块负荷 斑块体积 斑块出血 斑块钙化 斑块强化 斑块分布（腹/背/上/下） 血管壁重构模式,10,易损斑块的四大病理特征,11,与组织病理学切片的交叉验证,12,利用多对比度磁共振信号特征可以区分斑块当中不同的成分,LRNC:大的富含脂质的坏死核心,13,主要序列及优势,14,斑块出血：斑块不稳定的标志之一

4、,A 72-year-old woman with basilar artery plaque and acute pontine infarction,15,16,斑块强化:与卒中复发相关,International Journal of Stroke 2016, Vol. 11(2) 171179,17,Representative brain MR finding of a stroke patient with intracranial atherosclerosis and recurrence. The patient was admitted with right side we

5、akness. Initial diffusion MR imaging (MRI) shows left internal capsular infarction (a, arrowhead) with left middle cerebral artery stenosis on time-of-flight MR angiography (b, arrow). High resolution MRI shows eccentric plaque with enhancement from T1 weighted gadolinium enhancement protocol (c, d,

6、 arrows) and heterogeneous signal from T2 weighted image (e, arrow). Five days after admission his weakness deteriorated with newly developed motor aphasia, and diffusion MRI disclosed additional multiple infarctions involving left middle cerebral artery territory (f, arrowhead),18,Another patient a

7、dmitted with right side weakness and initial brain imaging disclosed left pontine infarction from diffusion MR (g, arrowhead) and basilar artery stenosis(h, arrow). The plaque from high resolution MRI shows enhancing lesion (i, j, arrows) with heterogeneous signal (k, arrow). Two months after discha

8、rge she was admitted again with right side hypesthesia. Diffusion MRI shows another left pontine infarction(l, arrowhead).,19,斑块重构（阳性重构/阴性重构）,RI 1.05 was defined as positive remodeling (PR) and RI1.05 as non-PR. VA (MLN) RI= VA(REF) 阳性重构血管较之阴性重构血管更可能发生血管事件 症状性狭窄处血管阳性重构明显多于阴性重构 阳性重构较阴性重构更常见微栓子信号,20,斑块分布：影响复发风险及梗死类型,症状性大脑中动脉狭窄，斑块更容易出现在上象限 症状性基底动脉狭窄，斑块更容易出现在腹侧,21,22,斑块钙化争议,Stroke. 2(Stroke. 2011;42:3447-3453011