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,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,/75,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,/75,单击此处编辑母版标题样式,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,/75,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,/75,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,/75,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,/87,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,/87,击此处编辑母标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,单击此处编辑母版标题样式,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,单击此处编辑母版标题样式,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,单击此处编辑母版标题样式,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,/87,单击此处编辑母版标题样式,Characterization of Intracranial Artery Moyamoya Angiopathy by High-resolution MR,颅内动脉烟雾状,血管病的,HR-MRI,研究,Characterization of Intracrani,1,内,容,烟雾病的病理改变及诊断标准,基于,HRMRI,研究烟雾病与脑梗死相关性,HRMRI,血管壁特征与,动脉粥样硬化相关因素的关系,内 容烟雾病的病理改变及诊断标准基于HRMRI研究烟雾病,烟雾病定义,烟雾病又名,moyamoya,病,(MMD),或脑底异常血管网病,以脑血管造影发现,双侧,颈内动脉虹吸部及大脑前中动脉起始部,严重狭窄或闭塞,,颅底软脑膜、穿通动脉等小血管代偿增生形成,脑底异常血管网,为特征的一种慢性,进行性,闭,塞性脑血管疾病,1957,年由日本学者最早报道,因在血管造影中脑底异常血管,的,形状酷似,一团,烟雾,故称之烟雾病,Weinberg, Arnaout et al. 2011,Takeuchi K, et al. Brain,Nerve,1957,烟雾病定义烟雾病又名moyamoya病(MMD)或脑底异常血,诊断标准,2012,年版日本烟雾病委员会制定的烟雾病的诊断标准,脑动脉,造影,脑动脉造影可作为独立的诊断标准,,至少应符合以下标准,:,颈内动脉终,末段(,TICA,)和(或)大脑前动脉(,ACA,)起始段和(或),大脑中动脉,(,MCA,)起始段严重,狭窄,或闭塞,;,动脉期在闭塞动脉周围有,异常血管网,(侧枝循环),;,上述病变应该是,双侧,的。,磁,共振成像(,MRI,) 如果磁共振血管成像(,MRA,)和,MRI,清晰地显示以下改变,无需做数字减影血管造影(,DSA,)检查也可以诊断,:,TICA,、,ACA,起始段和,MCA,起始段严重,狭窄,或闭塞,;,脑基底部,异常血管网,(侧枝循环),,,如果在,MRI,上看到,2,个以上明显的血管流空影,也可以认为有异常血管网,;,上述改变为,双侧,。,诊断标准2012 年版日本烟雾病委员会制定的烟雾病的诊断标准,MMD,诊断流程,Moyamoya disease (MMD): 84%,Unilateral MMD: 10.5%,Quasi-MMD,:,5.4-30%,Fujimura M, et al. Neurol Med Chir (Tokyo). 2015,Hayashi K, et al. Clin Neurol Neurosurg. 2013,Moyamoya syndrome,Probable MMD,akin-MMD,moyamoya phenomenon,moyamoya-like vasculopathy,moyamoya angiopathy,动脉粥样,硬化,;,自身,免疫性疾病,;,脑,膜炎,;,脑肿,瘤,;,唐氏综合症;,神经纤维,瘤病,;,颅外伤;,放射线头部,照射,;,其,他原因。,MMD诊断流程Moyamoya disease (MMD):,病理进展,受累血管,狭窄闭塞,脑底异常,血管网,脑血管,事件,遗传因素,血管增生,免疫炎症,病理发现,颈内动脉远端(,TICA,)和,Willis,环周围动脉,如大脑前、中和后动脉有,不同程度的狭窄或闭塞,,Willis,环周围和软脑膜上大量小血管网形成(穿通动脉和吻合血管);,病理改变为,内膜纤维增生,、内弹力层和中层变薄,,通常没有炎性细胞或粥样硬化改变,;,Yamashita M, et al. stroke. 1983.,Takekawa Y, et al. Neuropathology. 2004,Scott RM, et al. N Engl J Med. 2009.,病理进展受累血管脑底异常脑血管遗传因素病理发现 Yamash,临床,特点,63.4%,脑缺血,受累血管,狭窄闭塞,脑底异常,血管网,脑血管,事件,遗传因素,血管增生,免疫炎症,临床特点63.4%脑缺血受累血管脑底异常脑血管遗传因素,铃木分期(,Suzukis stages,),Suzuki J, et al. Arch Neurol. 1969.,Stage 1: Narrowing of Carotid Fork,,颈内动脉分叉,狭窄期,,末端分叉处,狭窄,无其他异,常。,Stage 2: Initiation of the Moyamoya,,烟雾血管,形成期,,,颈内动脉末端分叉处狭窄,颅底有烟雾血管形成,,大脑前动脉和大脑中动脉的分支扩张,,尚没有颅外至颅内的侧枝循环形成。,Stage 3: Intensification of the Moyamoya,,烟雾血管,增,多期,,,ACA,和,MCA,主要分支缺失,,烟雾血管非常明显,,形成血管团,,,无法识别血管团,的每一条动脉。,PCA,或后交通不受影响,无颅外至颅内的侧枝循环形成。,Stage 4: Minimization of the Moyamoya,,,烟雾血管,衰减期,,,烟雾状血管开始减少,从颅外到颅内的侧枝循环逐渐形成。,Stage 5: Reduction of the Moyamoya,,烟雾血管,减,少期,,,从,ICA,发出的全部主要动脉完全消失,烟雾血管比第,4,期更少,从颅外到颅内的侧枝供血进一步增多。,Stage 6: Disappearance of the Moyamoya,,,烟雾,消失期,,,烟雾状血管完全消失,仅见到从颅外进入颅,内的侧枝循环,,,ICA,对颅内的,供血完全,消失,,脑循环完全依靠颈外动脉或椎动脉,。,颈内动脉末端分叉处狭窄,烟雾血管,(形成,-,增多,-,衰减,-,减少,-,消失),颅外侧枝循环,铃木分期(Suzukis stages)Suzuki J,MRA,分期,a,Normal or equivocal stenotic change in the left M1 portion.,b,Moderate stenotic change in the horizontal portion of the left MCA (M1).,c,Severe signal decrease or loss of the left M1 portion and its distal branches.,d,The left M1 portion and its distal branches are difficult to identify.,Houkin K, et al. Cerebrovasc Dis. 2005,正常,狭窄,断续,消失,MRA分期a Normal or equivocal ste,R: Stage II; L:Stage IV,CBF,MTT,T0,TTP,R,L,R,L,Stage 2,: Initiation of the Moyamoya,,烟雾血管形成期,颈内动脉末端分叉处狭窄,颅底有烟雾血管形成,大脑前动脉和大脑中动脉的分支扩张,尚没有颅外至颅内的侧枝循环形成,。,Stage 4,: Minimization of the Moyamoya,,烟雾血管衰减期,烟雾状血管开始减少,从颅外到颅内的侧枝循环逐渐形成,。,灌注:左侧大脑半球血流减慢,血流量没有显著增加,并没有代偿出足够的灌注,处于失代偿,脑梗死,CBV,R: Stage II; L:Stage IVCBFMTTT,Stage IV,CBF,MTT,T0,TTP,R,L,Stage,4,: Minimization of the Moyamoya,,烟雾血管衰减期,烟雾状血管开始减少,从颅外到颅内的侧枝循环逐渐形成,。,灌注:两侧大脑半球灌注基本代偿,没有脑梗死,CBV,Stage IVCBFMTTT0TTPRLStage 4:,FFE,-T2*PWI &,PRESTO,-T2*,PWI,3D,多次激发,FFE-EPI,技术,TETR,rCBV,rCBF,MTT,T0,TTP,PRESTO,-T2*PWI,FFE,-T2*PWI,FFE-T2*PWI & PRESTO-T2*PWI3D多,Temporal delay areas in Time Shift Analysis of BOLD in stroke,5 days,after stroke onset,T2*PWI TTP,TSA,MRA,DWI,Temporal delay areas in Time S,8 days,After stroke onset,Temporal delay (hypoperfusion) was more likely to be present in stroke patients with intracranial large-vessel occlusion or stenosis,T2*PWI TTP,TSA,MRA,DWI,Temporal delay areas in Time Shift Analysis of BOLD in stroke,8 daysT2*PWI TTP TSA MRA DWI T,内,容,烟雾病的病理改变及诊断标准,基于,HRMRI,研究烟雾病与脑梗死相关性,HRMRI,血管壁特征与,动脉粥样硬化相关因素的关系,内 容烟雾病的病理改变及诊断标准基于HRMRI研究烟雾病,高分辨血管壁成像,PDVISTA,T1VISTA,T1VISTA/C+,高分辨血管壁成像PDVISTAT1VISTAT1VISTA/,PDVISTA,T1VISTA,T1VISTA/C+,烟雾病,双侧颈内动脉弥漫斑块形成,环形增厚,大动脉炎可能(中枢神经系统血管炎),女,,46,岁,无高血压,高血脂,高血糖病史,PDVISTAT1VISTAT1VISTA/C+烟雾病,双侧,原发性中枢神经血管炎,原发性中枢神经血管炎,3/87,颅内动脉烟雾状血管病的HR-MRI研究-学习ppt课件,3/87,颅内动脉烟雾状血管病的HR-MRI研究-学习ppt课件,3/87,烟雾病血管壁强化与脑梗死相关性研究,Background and Purpose,:,Moyamoya,vasculopathy (MMV) is a progressive stenosis of intracranial arteries at the distal portion of the internal carotid artery (ICA) and the proximal anterior and middle cerebral arteries, which can result in transient ischemic attacks or strokes.,We,investigated the characteristics of intracranial vessel enhancement and the relationship between vessel enhancement and ischemic infarction in patients with MMV.,烟雾病血管壁强化与脑梗死相关性研究Background an,血管壁强化程度分级,MMV enhancement is defined as,follows:,grade,0 indicates no enhancement (Fig 1);,grade,1, vessel wall shows mild enhancement and less than that of the pituitary,infundibulum,(Fig 2);,grade,2, obvious enhancement, which is similar to or greater than that of the infundibulum (Fig 3).,垂体柄为强化程度分级参照物。,Radiology. 2014 May;271(2):534-42,血管壁强化程度分级MMV enhancement is de,烟雾病血管壁(无强化),Figure 1. Grade 0 enhancement of MMV. A, TOF MRA shows right MCA and ACA disappeared and stenosis of left MCA. B, Pre- and C, post-enhanced images show the stenosis of right distal ICA with no enhancement.,烟雾病血管壁(无强化)Figure 1. Grade 0 e,烟雾病血管壁(,轻度同心圆强化,),MERGE,R,L,Figure 2. Grade 1 enhancement of MMV. A, TOF MRA shows that bilateral MCA are discontinuous. B, Pre- and C, post-enhanced images show the stenosis of right proximal ACA with mild enhancement (red arrow and arrow head) but less than that of pituitary infundibulum (yellow arrow).,烟雾病血管壁(轻度同心圆强化)MERGERLFigure,烟雾病血管壁,(明显强化,),Figure 3. Grade 2 enhancement of MMV. A, TOF MRA shows bilateral MCA disappeared. C, DWI shows acute ischemic infarction of left frontal lobe. B, Pre- and post-enhanced images show stenosis of left distal ICA, proximal MCA and ACA (red arrow and arrow head). The enhancement in the bifurcation of left distal ICA is greater than that of pituitary infundibulum (yellow arrow).,R,L,烟雾病血管壁(明显强化)Figure 3. Grade 2,烟雾病血管壁明显强化是,脑梗死的独立预测因子,Acute Infarction,group,(n=25),Non-acute Infarction group (n=22),P Value,Enhancement of MMV,Grade 2,26,8,0.011,Grade 1,11,11,Grade 0,92,98,Grade 2 enhancement,was independently associated with ischemic infarction (OR = 22.5; 95% CI: 2.3 - 223.4;,P,= 0.008,),whereas,grade 1 enhancement was not (OR = 3.7; 95% CI: 0.3 - 42.4;,P,= 0.287),after,adjusted for hypertension when grade 0 was considered as reference.,烟雾病血管壁明显强化是脑梗死的独立预测因子Acute I,烟雾病血管强化与炎症过程有关,血管壁强化多见:,80.9,% patients with MMV in this study had enhanced moyamoya-affected vessel,wall.,向心性强化:,MMV,enhancement were commonly concentric and located in the distal,ICA.,活动性血管生成:,There is an,active angiogenetic process in the enhanced vessel wall in patients with MMV.,向心性强化与炎症有关:,In,extracranial vessel, inflammatory conditions had been thought to be associated with concentric, circumferential wall thickening and enhancement with pathologic,confirmation.,动脉粥样硬化斑块与炎症有关:,A,strong inflammatory response in patients with atherosclerotic plaque reflected increased macrophage infiltration and,neovascularity.,烟雾病血管壁强化也可能与炎症有关:,Our,results extend those observations to moyamoya-affected vessels by suggesting concentric enhancement of intracranial vessels in patients with MMV may indicate inflammatory response in patients with MMV.,烟雾病血管强化与炎症过程有关血管壁强化多见:80.9% pa,内,容,烟雾病的病理改变及诊断标准,基于,HRMRI,研究烟雾病与脑梗死相关性,HRMRI,血管壁特征与,动脉粥样硬化相关因素的关系,内 容烟雾病的病理改变及诊断标准基于HRMRI研究烟雾病,入组标准,Fujimura M, et al. Neurol Med Chir (Tokyo). 2015,Hayashi K, et al. Clin Neurol Neurosurg. 2013,动脉粥样,硬化,;,自身,免疫性疾病,;,脑,膜炎,;,脑肿,瘤,;,唐氏综合症;,神经纤维,瘤病,;,颅外伤;,放射线头部,照射,;,其,他原因。,2013,年,10,月,-2014,年,12,月,南京,大学附属鼓楼医院神经,外科,20,例烟雾病,患者,23,例动脉粥样硬化型烟雾综合征患者,入组标准Fujimura M, et al. Neurol,动脉粥样硬化诊断标准,动脉粥样硬化是指有,2,个或,2,个以上动脉粥样硬化危险因素和(或)存在大中动脉粥样,硬化的证据。,动脉粥样硬化,危险因素,包括如下:,(,1,)年龄(男性,55,岁,女性,60,岁),;,(,2,)高血压(收缩压,l40mmHg,,舒张压,90mmHg,,或者目前正在服用降压药物),;,(,3,)高脂血症,(,总胆固醇,5.20mmol/L,,或甘油三酯,1.70mmol/L,,或低密度脂蛋白,3.12mmol/L,,或正在服用降血脂药物,),;,(,4,)糖尿病,(,空腹糖,7.0mmol/l,,餐后,2,小时血糖,11.1mmol/l,,或使用胰岛素降糖药物),;,(,5,)吸烟与肥胖。,Tanaka M,et al.J,Stroke Cerebrovasc Dis.,2012.,动脉粥样硬化诊断标准 动脉粥样硬化是指有2个或2个以上动脉粥,临床资料,MMD,(,N=20),AS-MMS,(N=23),P,值,年龄(岁),43.27.92,55.227.73,0.001,女性(,%,),13(65.0),9,(,39.1,),0.129,高血压(,%,),4(20),18,(,78.3,),0.001,高血脂(,%,),4(20),9,(,39.1,),0.203,糖尿病(,%,),0,10,(,43.5,),吸烟(,%,),6(30),9,(,39.1,),0.749,临床表现,脑梗死(,%,),3(15),12,(,52.2,),0.023,脑出血(,%,),10(50),3,(,13,),0.018,TIA,(,%,),5(25),8,(,34.8,),0.526,头痛(,%,),1(5),0,头晕(,%,),1(5),0,注:,MMD,指烟雾病;,AS-MMS,指动脉粥样硬化烟雾综合征;,TIA,指短暂性脑缺血发作。,临床资料MMDAS-MMSP值年龄(岁)43.27.92,血管壁,评估内容及标准,管腔狭窄形态,特点(偏心性,、,向,心性,),:如果血管横断面的管腔显示圆形或近似圆形,管壁厚度均一,则为同心性(,concentric,);反之,则为偏心性(,ecentric,),。,管壁,信号均质性,:如果狭窄血管壁的成分在,MERGE,增强序列上出现不等信号则为不均质性(,heterogeneous,);反之,则为均质性(,homogeneous,),。,血管外径,(,outer diameter,)测量:在高分辨率图像上选取的层面,测量时要求测量线必须通过管腔中心,取不同方向测量值的平均值,。,血管面积,(,vessl area,)、,管腔面积,(,lumen area,):在选取的横断面上血管外缘围成的面积及血管内缘围成的面积。管壁面积(,wall area,)的计算:管壁面积,=,血管面积,-,管腔面积,。,血管壁评估内容及标准 管腔狭窄形态特点(偏心性、向心性):如,HRMRI,结果,MCA,MMD,(,N=21),AS-MMS,(N=18),P,值,同心性狭窄(,%,),17,(,81,),3(16.7),0.001,均匀增强(,%,),19,(,90.5,),6(33.3),0.001,血管外径(,mm,),2.970.41,3.480.66,0.016,管壁面积(,mm2,),6.481.86,8.662.89,0.001,注:,MMD,指烟雾病;,AS-MMS,指动脉粥样硬化烟雾综合征;,MCA,指大脑中动脉,。,MMD,(,N=40,),AS-MMS,(,N=34,),P,值,同心性狭窄(,%,),25,(,62.5,),1,(,2.9,),0.001,均匀增强(,%,),27,(,67.5,),1,(,2.9,),0.001,血管外径(,mm,),4.670.85,5.610.94,0.001,管壁面积(,mm2,),14.34.25,19.856.57,0.001,ICA,末端(,C1,起始段,),HRMRI结果MCAMMDAS-MMSP值同心性狭窄(%),MCA,环形,vs,.,偏心性斑块,Naghavi, et al. Circulation. 2003,Yamashita M, et al. stroke. 1983.,Takekawa Y, et al. Neuropathology. 2004,Scott RM, et al. N Engl J Med. 2009.,AS,-MMS,动脉粥样硬化烟雾综合征,MMD,烟雾病,MCA 环形 vs. 偏心性斑块Naghavi, et al,MMD vs. AS-MMS,管腔狭窄形态,特点,和,管壁,信号均质,性:,MMD,向心性,和均质,:动脉内膜增,厚,平滑肌细胞增生,内弹力层高度迂曲、分层、断裂,中膜萎缩变薄,平滑肌细胞明显减,少。,增厚的内膜在,HR-MRI,上表现为均质、同心性狭窄。,AS,-,MMS,偏心性和不均质:动脉内膜损伤后相继出现脂质点和条纹,、粥样斑块和纤维粥样斑块以及复合性病变,使纤维帽、脂质、坏死的纤维组织、钙化点、,血栓等出现在动脉壁中,.,血管外径,、,血管面积,、管腔面积,:,MMD,AS-,MMS,MMD,:,因为中膜萎缩变,薄,平滑肌细胞减少,故烟雾病的血管总体上病理性缩窄,AS-,MMS,:,动脉粥样,硬化性疾病血管大多呈现正向重构(,positive remodeling,,,PR,),血管壁向外代偿性增生扩张,MMD vs. AS-MMS管腔狭窄形态特点和管壁信号均质性,MMD,中的偏心斑块与信号不均,本研究中,MMD,患者的,ICA,末端,呈现偏,心性狭窄的比例较高(,37.5%,),管壁信号不均比例达(,32.5%,)。这可能与以下几点原因有关,:,颈内动脉相对大脑中动脉血管,直径较,粗,,内膜增厚可能出现分布不均,;,颈内动脉进,行性狭窄后,可能,继发,血栓,形成,附壁血栓造成偏心性,狭窄;,部分烟雾病患者可能,合并有动脉粥样,硬化,,入组标准中,烟雾病组只含有一个动脉粥样硬化危险因素的患者没有被排除,。,MMD中的偏心斑块与信号不均本研究中MMD患者的 ICA末端,研究的局限性,1.,烟雾病分期是否与强化有关?,本,研究中,MMD,组与,AS-MMS,组,,MCA,完全闭塞或难以与侧支循环区别,的比例比较高,分别占,47.5%,、,47.1,%,,,可能与,入组,的成年烟雾病患者大部分处于,Suzuki,分级,的中晚期,有关,。,2.,血管壁强化,与各种脑血管预后有关?,斑块特征与脑白质高信号与脑梗死转化,,以及出血转化关,系,,,如,急性梗死(,发生,时间,),慢性梗死(时间),,缺氧,性脑改变(脑白质高信号),分级,,,其他脑内病灶,3.,颈动脉的改变是否与烟雾病有关?侧枝循环的评估和脑灌注的评估,研究的局限性1. 烟雾病分期是否与强化有关?,影像指导下的精准化治疗,image-guide therapy,青年卒中血管病因学影像机制,男,,31,岁,突发失语伴头晕,6,小时,常规血管造影阴性,高分辨血管壁,HRMRI,发现夹层,影像指导下的精准化治疗image-guide therap,3/87,脑梗死的精准影像诊断,急性期脑梗死,HRMRI+MRA,TCD,CTA,DSA,MRS,各种原因栓子,颅内动脉粥样硬化斑块,30,类烟雾病,颅内动脉夹层,烟雾病,线粒体脑肌病,原发性中枢神经血管炎,Wei Y, et al. J Stroke Cerebrovasc Dis. 2013,表面现象,工具:,HRMRI,病因,脑梗死的精准影像诊断急性期脑梗死HRMRI+MRA, 各种原,影像指导下的精准化治疗,image-guide therapy,急性期脑梗死,HRMRI+MRA, TCD,CTA,DSA,各种原因栓子,30-40%,颅内动脉粥样硬化斑块,30,类烟雾病,颅内动脉夹层,烟雾病,原发性中枢神经血管炎,Wei Y, et al. J Stroke Cerebrovasc Dis. 2013,影像指导下的精准化治疗image-guide therap,血管壁增强的存在问题:,理解机制和规范扫描,When,the enhancement is,very clear,such as with vasculitis, a postcontrast scan may be,sufficient(,Figures 3 and 4),.,合并有炎症才会明显强化。,However, the contrast,enhancement can,also be,modest.,I,ntracranial,vessel wall,lesions may,already have a relatively hyperintense signal before,the administration,of contrast (Figure 2),.,增强前即为高信号。,In these more,difficult cases, precontrast and postcontrast MRI vessel wall imaging,is required,to establish the presence of contrast uptake.,Whether there,is an optimal time point between contrast,administrationand,peak enhancement needs to be determined.,Preliminary results,from 7 T MRI examinations show a contrast-,tonoise ratio,peak after,20 minutes,of contrast,administration (,Figure 4),.,Finally, the exact pathophysiological,mechanisms of,contrast uptake in the intracranial arterial walls,and atherosclerotic,plaques need to be established,.,颅内斑块及造影剂摄取的机制需要进一步探讨。,2014 Nikki Dieleman review Circulation,血管壁增强的存在问题:理解机制和规范扫描When the,血管壁病理与磁共振对照时存在的问题,A.G. van der Kolk 2015,7TMRI,with histopathology AJNR,血管壁病理与磁共振对照时存在的问题A.G. van der,3/87,A.G. van der Kolk 2015 7TMRI with histopathology AJNR,A.G. van der Kolk 2015 7TMRI w,3/87,组织学检查显示纤维斑块和蛋白聚,糖,,,胶原升高,泡沫样巨噬细胞,胶原在所有序列都是高信号,泡沫样巨噬细胞是低信号,内膜中膜伪影,血管壁病理与磁共振对照时存在的问题,A.G. van der Kolk 2015 7TMRI with histopathology AJNR,组织学检查显示纤维斑块和蛋白聚糖,胶原升高,泡沫样巨噬细胞血,3/87,A.G. van der Kolk 2015 7TMRI with histopathology AJNR,HR-MRI,信号理解的注意事项,离体扫描注意事项:,去除腔内血块,减少异物伪影,标本固定在琼脂糖中,减少空气伪影,(磁敏感伪影),活体扫描注意事项:,斑块内复杂成分(出血和钙化)导致的磁敏感伪影,斑块周围脂肪和脑脊液成分导致的化学位移伪影,斑块内胶原和泡沫样巨噬细胞,内膜和中膜间隙导致图像信号理解困难,A.G. van der Kolk 2015 7TMRI w,3/87,小结和展望,HRMRI,技术提供了观察颅内动脉管壁的可能,MMD,颅内动脉管壁增强是脑梗死发生的独立预测因子,MMD,中多数为向心性和均匀斑块,动脉粥样硬化多数为偏心性和不均匀斑块,评估,MMD,预后时应综合考虑分期、侧枝循环和脑灌注状态,颅内动脉管壁与颈内动脉管壁结构差异,斑块成分复杂,,导致理解困难,有待于对,MMD,闭塞和微小动脉,以及,MMD,斑块的特异性成像技术,MMD,病因有待于深入探讨,除动脉粥样硬化之外,还可以测定炎症和免疫细胞,因子,如趋化因子和黏附分子、血管增生相关分子、调节性,T,细胞,小结和展望HRMRI技术提供了观察颅内动脉管壁的可能,3/87,Thank you!,Thank you!,
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