脑血管形态学类型与脑动脉瘤形成相关性研究

目的 研究脑血管形态学类型与脑动脉瘤形成的相关性.方法 截取1081份正常MRA图像定义为一般国人脑血管形态学类型,按颈内动脉供血范围进行分型,将一侧颈内动脉只供应同侧大脑前动脉和大脑中动脉定义为标准均衡型,将一侧颈内动脉不仅供应同侧大脑中动脉和大脑前动脉同时还供应对侧全部或部分大脑前动脉,而对侧大脑前动脉A1段明显变细(管径<对侧1/2)、发育不良或未发育定义为一侧优势型,将一侧大脑后动脉主要由同侧颈内动脉通过胚胎大脑后动脉供血定义为前循环优势型进行分析.对175例动脉瘤患者脑血管形态学类型与一般国人脑血管形态学类型进行对照,研究脑血管形态学类型与脑动脉瘤形成的相关性.结果 49例前交通动脉瘤中一侧优势型占87.76%(45例),与正常国人一侧优势型和标准均衡型构成有显著性差异(P<0.0001).其中左侧优势型(33例)约为右 侧优势型(12例)的3倍,与一般人群左侧优势与右侧优势型 比(11.19%/3.98%)无显著性差异(P=0.952).而且左右侧前交通动脉瘤数目构成与临床一般人群一侧优势型左右侧构成无显著性差异(P=0.544).58例颈内动脉-后交通动脉瘤患者中前循环优势型(21例)与标准均衡型(27例)构成与正常国人脑血管类型前循环优势型(224例)及标准均衡型(762例)构成存在显著性差异(P=0.0008).前交通动脉瘤、后交通动脉瘤、多发动脉瘤中脑血管类型异常比例均与正常国人脑血管类型异常比例之间存在显著性差异,而M1远端分叉处动脉瘤脑血管类型异常比例与正常国人脑血管类型异常比例之间不存在显著性差异.结论 一侧优势型供血与前交通动脉瘤的形成相关,造成前交通动脉瘤左右侧差异的原因是因为一侧优势型发育左右侧存在差异.Willis环的变异是Willis环上动脉瘤形成的一个重要因素.     

3D-CTA大脑前动脉A1-A2段夹角测量与前交通动脉瘤相关性研究

目的:探讨大脑前动脉A1-A2段夹角与前交通动脉(anterior communicating arterv,ACoA)动脉瘤发生的关系.方法:回顾性分析32例前交通动脉瘤及随机选取的同期35例非前交通动脉瘤影像学资料,利用3D-CTA测量A1-A2段夹角(外侧夹角);同时探讨其对前交通动脉瘤形成的可能影响.结果:32例前交通动脉瘤中,有19例大脑前动脉为A1段优势型,13例表现为A1段均衡型.3D-CTA所测得前交通动脉瘤组A1-A2段夹角平均值为99.0°±18.8°,而非前交通动脉瘤组夹角平均值为118.1°±16.4°,两者间具有统计学差异(P<0.001).A1段均衡型动脉瘤侧A1-A2段平均夹角为96.3°±18.8°,较非动脉瘤侧平均夹角(115.2°±15.3°)小11.9°±3.3°(P<0.05);结论:较小的A1一A2交界处夹角更容易发生前交通动脉瘤,这可能与该处不恰当成角造成的血流动力学改变有关.     

脑底动脉环应用解剖与DSA对照分析

目的：通过脑底动脉环前半部解剖变异与脑血管DSA对照分析，探讨大脑前动脉(ACA)与前交通动脉(AcoA)及其与动脉瘤发生的关系。资料与方法：脑血管标本35具，观察脑底动脉环解剖结构及其变异。全脑血管DSA 50例。脑底动脉瘤57例，其中前交通动脉瘤13例，后交通动脉瘤24例，其他部位动脉瘤20例。结果：35具脑血管标本2具右侧A1发育不全，3具A1血管为多支及走行方向变异。全脑血管DSA50例，A1发育异常20例，其中一侧A1缺如9例，纤细11例。脑底动脉瘤57例，大脑前动脉A1纤细、缺如18例，其中前交通动脉瘤13例，颈内动脉前三分叉变异7例，动脉瘤发生部位与前交通动脉血流方向一致。结论：脑底动脉环前部的变异极为复杂，右侧变异多于左侧，与动脉瘤发生的关系密切。     

64排CTA对前交通动脉复合体变异类型与前交通动脉瘤相关性研究

目的利用64排螺旋CT血管成像(CTA),研究前交通动脉复合体变异类型与前交通动脉瘤(anteriorcommunicating aneurysms,ACoA)发病及破裂出血的相关性。资料与方法回顾性分析620例脑部CTA表现及临床资料,选取48例ACoA患者为研究组,121例无动脉瘤患者为对照组,分析A1段、前交通动脉影像表现及类型,比较ACoA发病、破裂出血与复合体变异、变异侧别的相关性。结果大脑前动脉A1段成窗畸形少见约3%,与ACoA发病无相关性。ACoA患者A1段变异发生率50%,对照组患者A1段变异发生率为31%,ACoA患者A1段变异发生率高于对照组,差异有显著统计学意义(χ2=5.12,P<0.05),存在明显左侧优势(χ2=7.79,P<0.01)。前交通动脉异常型发生率在ACoA患者中与对照组差异无统计学意义(χ2=0.72,P>0.05)。24例复合体变异的ACoA,动脉瘤破裂、蛛网膜下腔出血程度与复合体变异相关(Z=-2.63,P<0.05)。结论 CTA能清晰地显示前交通动脉复合体变异,前交通复合体变异与ACoA发病及破裂后出血严重程度相关。     

218例前交通动脉瘤三维CT血管造影临床分析

目的：对前交通动脉瘤的三维CT血管造影（three dimensional computed tomographic angiography,3D-CTA）结果进行分析。方法：总结分析了我院近6年经手术证实的218例前交通动脉瘤的影像学资料,随机选取220例非前交通动脉瘤的3D-CTA作为对照。结果：218例前交通动脉瘤中,180例为动脉瘤侧大脑前动脉灿段呈优势供血,对侧大脑前动脉A1段纤细或缺如,血管影像出现明显的A1优势征;对照组中,210例的大脑前动脉血管影像双侧对称,无以上表现,仅10例出现“A1优势征”。结论：双侧大脑前动脉发育不均衡是形成前交通动脉瘤的高危因素,出现“A1优势征”的患者应积极随访观察。     

前交通动脉瘤与大脑前动脉A1段缺如相关性研究

目的：探讨前交通动脉瘤（ACoA）发病及伴蛛网膜下腔出血与大脑前动脉A1段缺如的相关性。方法：回顾性分析705例全脑血管造影及临床资料,其中47例ACoA患者为研究组,129例无脑血管病变患者为对照组,比较ACoA发病、动脉瘤大小及蛛网膜下腔出血与大脑前动脉A1段缺如相关性。结果：47例ACoA患者中,大脑前动脉A1段缺如发生率为44.7%,对照组129例患者中大脑前动脉A1段缺如发生率为9.3%,ACoA患者伴大脑前动脉A1段缺如发生率明显高于对照组,差异有显著性意义（χ^2=28.303,P〈0.001）。21例伴A1段缺如的ACoA动脉瘤平均直径（5.8±2.8）mm,26例无A1段缺如的ACoA动脉瘤平均直径（4.2±2.2）mm,二者差异有显著性意义（t=2.098,P〈0.05）。21例伴A1段缺如的ACoA,其蛛网膜下腔出血程度与大脑前动脉A1段缺如相关（Z=-2.199,P〈0.05）。结论：前交通动脉瘤发病、动脉瘤大小以及伴发蛛网膜下腔出血均与大脑前动脉A1段缺如相关,大脑前动脉A1段缺如患者的ACoA发生率明显增高。     

大脑前动脉A1段变异与前交通动脉瘤相关性的CTA研究

目的探讨大脑前动脉A1段变异与前交通动脉瘤发生的相关性。方法回顾性分析132例脑CTA资料,其中42例前交通动脉瘤为研究组,90例无脑血管病变为正常对照组,比较两组大脑前动脉A1段变异的差异。结果前交通动脉瘤组大脑前动脉A1段变异率(78.6%)明显高于正常对照组(18.9%),差异有统计学意义(χ~2=43.349,P0.001)。结论大脑前动脉A1段变异与前交通动脉瘤发病存在相关性。CTA能清晰地显示前交通动脉瘤的情况,为治疗提供重要依据。     

Willis环变异与交通动脉瘤发生的相关性研究

目的探讨Willis环变异与交通动脉瘤发生的相关性。方法采用双源Flash CT血管成像技术,回顾性分析102例交通动脉瘤患者的临床及影像学资料,同期行颅脑CTA检查未见交通动脉瘤的患者42例作为对照组,观察交通动脉瘤的形态以及Willis环变异特点。结果前交通动脉瘤(ACoAA)、后交通动脉瘤(PCoAA)患者中Willis环变异率分别为69.2%、72%,对照组为45.2%;其中ACoAA组中大脑前动脉A1段变异率61.5%,PCoAA组中大脑后动脉P1段变异率48%,而对照组中分别为14.3%、23.8%;以上各组间比较均有显著性差异(P0.05)。另外ACoAA组中,右侧Al段发育变异的发生率明显高于左侧(P0.01)。结论 Willis环变异与交通动脉瘤的发生存在一定的相关性,特别是大脑前动脉A1段和大脑后动脉P1段的变异。同时,还发现了Willis环的一些少见变异。     

双能量减影CTA对颅内动脉窗式变异的诊断

目的探讨双能量减影CTA(DE-CTA)对颅内动脉窗式变异的诊断价值,了解颅内动脉窗式变异的CTA表现、检出率及好发部位。方法 2009年3月~2014年1月期间,回顾性分析我院3148例经头颈部DE-CTA诊断为颅内动脉窗式变异218例患者的影像学资料,分析颅内动脉窗式变异的发生率、部位、形态特征及合并症。结果 1在3148例患者中,检出颅内动脉窗式变异224个窗(218例),检出率为7.12%,其中位于基底动脉132个(4.19%),椎动脉45个(1.43%),大脑前动脉及前交通动脉43个(1.37%),大脑中动脉4个(0.13%)。5例为基底动脉与椎动脉2个窗式变异,1例为基底动脉与前交通动脉2个窗式变异;2基底动脉中,128个窗位于中下1/2段,4个窗位于中上1/2段;椎动脉中,V3段27个窗(左侧16个,右侧11个),V4段18个窗(左侧8个,右侧10个);大脑前动脉及前交通动脉中,A1段9个窗(左侧4个,右侧5个),A2段6个窗(左侧2个,右侧4个),A1与A1交界区3个窗(左侧2个,右侧1个),前交通25个窗;大脑中动脉4个窗均位于M1段;3根据血管变异形态分型:裂隙型126个,凸透镜型72个,重复型26个。9例合并颅内动脉瘤。结论双能量减影CTA能清楚、直观、准确的诊断颅内动脉窗式变异及所合并的其他血管病变。     

DSA全脑血管造影431例分析

目的:分析431例全脑血管造影,探讨颅内血管病变用DSA全脑血管造影的价值。材料和方法:92年至96年行DSA全脑血管造影431例。采用Seldinger技术,经股动脉穿刺置管行选择性或/和超选择性全脑血管造影。前交通及后交通动脉瘤经显微神经外科证实。结果:动脉瘤155例,血管畸形76例,占位性病变48例。颅内动脉瘤发生在大脑前动脉系统为42.58％,而前交通动脉瘤为大脑前动脉系统的74.24％。颅内动脉瘤为全脑血管造影阳性发现的首位,其次为血管畸形,颅内占位。本组阴性率为25.75％。结论:CT、MR发现颅内出血或血管畸形时,不一定全脑血管造影有阳性改变。     

Effects of Circle of Willis Anatomic Variations on Angiographic and Clinical Outcomes of Coiled Anterior Communicating Artery Aneurysms

BACKGROUND AND PURPOSE:Anterior communicating artery aneurysms account for one-fourth of all intracranial aneurysms and frequently occur in the context of A1 vessel asymmetry. The purpose of this study was to correlate circle of Willis anatomic variation association to angiographic and clinical outcomes of anterior communicating aneurysm coiling.MATERIALS AND METHODS:The Cerecyte Coil Trial provides a subgroup of 124 cases with anterior communicating artery aneurysms after endovascular coiling. One hundred seventeen of 124 anterior communicating artery aneurysms had complete imaging and follow-up for clinical outcome analysis, stability of aneurysm coil packing, and follow-up imaging between 5 and 7 months after treatment. Clinical outcomes were assessed by the mRS at 6 months.RESULTS:Anterior cerebral artery trunk-dominance was seen in 91 of 124 (73%) anterior communicating artery aneurysms and codominance in 33 of 124 (27%) anterior communicating artery aneurysms. There was no significant difference (P > .5) in treatment success at 5–7 months for anterior communicating artery aneurysms between the anterior cerebral artery trunk-dominant (49 of 86, 57%) and anterior cerebral artery trunk-codominant (19 of 31) groups. Angiographic follow-up demonstrates a statistically significant increase in neck remnants and progressive aneurysm sac filling with the A1 dominant configuration (n = 21, 24% at follow-up versus n = 11, 12% at immediate posttreatment, P = .035). There was no statistically significant difference in clinical outcomes between types of anterior cerebral artery trunk configuration (P > .5).CONCLUSIONS:Anterior communicating artery aneurysms with anterior cerebral artery trunk-dominant circle of Willis configurations show less angiographic stability at follow-up than those with anterior cerebral artery trunk-codominance similar to other “termination” type aneurysms. This supports the hypothesis that anterior cerebral artery trunk-dominant flow contributes to aneurysm formation, growth, and instability after coiling treatment.

The most common site of intracranial aneurysms is the anterior communicating artery (AcomA). AcomA aneurysms account for approximately one-fourth of all intracranial aneurysms.¹ Also very common in the setting of AcomA aneurysms is unilateral anterior cerebral artery trunk (A1) dominance where 1 side supplies both pericallosal artery (A2) arteries, a well-known phenomenon previously shown to be a potent risk factor for AcomA aneurysm formation and rupture.^1–3To what extent vessel dominance influences the long-term result of endovascular packing of these aneurysms with detachable platinum coils and the patients'' clinical outcome is less well known.^4–6 One previous study indicates that vessel dominance is not a major factor in predicting short-term treatment outcome; however, the methodology and definition of vessel dominance as used in this instance was not stated.⁷ Yet, anterior communicating aneurysms are commonly “termination type” with the aneurysm forming with a relatively wide neck at the site of the inferred jet of flowing blood dynamics, with main branches nearly perpendicular to the parent vessel, also commonly seen for basilar tip, internal carotid tip, and middle cerebral bifurcations.⁸The Cerecyte Coil Trial (CCT) was a prospective, randomized, controlled study that entered 500 cases comparing endovascular coiling of ruptured and unruptured cerebral aneurysms with either Cerecyte or bare platinum coils that showed no difference between groups.^9,10 There was an expected large subset of AcomA aneurysms within the CCT cohort (n = 124).⁹ Therefore, data from this trial provided a unique opportunity to obtain a large number of AcomA aneurysm cases for determination of A1 dominance in relation to coiling treatment and angiographic outcomes immediately posttreatment and at follow-up. Our goal was to determine the impact of A1 dominance on treatment success, stability, and clinical outcomes of endovascularly coiled AcomA aneurysms.     

64层螺旋CT头颈动脉联合成像诊断颅内动脉瘤的应用价值

 目的 评价64层螺旋CT诊断颅内动脉瘤的临床应用价值。方法 选取我院176例颅内动脉瘤患者的头颈CTA(computed tomographic angiography,CTA)检查资料,评价颅内动脉瘤的大小、形态、位置及术后情况。结果 176例均行数字减影血管造影(digital subtraction angiography,DSA)存在动脉瘤(157经手术治疗),共计 201个动脉瘤,其中19例为多发动脉瘤。首次CTA明确诊断动脉瘤171例(196个),漏诊5例,阳性诊断率97.5%(196/201)。171例(196个)中颈内动脉瘤112例,后交通动脉瘤10例,前交通动脉瘤26例,基底动脉瘤5例,大脑中动脉瘤13例,大脑前动脉瘤5例,对照DSA再次重组首次漏诊的5例CTA图像,又发现动脉瘤2例,阳性诊断率提高至98.5%。结论 应用多层螺旋CT头颈血管联合成像选择合理的后处理方法,有助于提高图像质量与诊断的准确性,对临床术前评估与术后评价有重要意义。     

Patient-specific computational modeling of cerebral aneurysms with multiple avenues of flow from 3D rotational angiography images

RATIONALE AND OBJECTIVES: Previous studies of aneurysm flow dynamics based on three-dimensional (3D) rotational angiography (RA) images were limited to aneurysms with a single route of blood inflow. However, aneurysms of the circle of Willis frequently involve locations with more than one source of inflow, such as aneurysms of the anterior communicating artery. The highest resolution images of cerebral vessels are from RA images, but this technique is limited to visualizing only one route of inflow at a time, leaving a significant limitation in the application of 3DRA image sets for clinical studies of patient-specific computational fluid dynamics (CFD) simulations. In this report, subject-specific models of cerebral aneurysms with multiple avenues of flow are constructed from RA images by using a novel combination of image co-registration and surface merging techniques. MATERIALS AND METHODS: RA images are obtained by means of contrast injection in each vessel that provides inflow to the aneurysm. Anatomic models are constructed independently of each of these vascular trees and fused together into a single model. The model is used to construct a finite element grid for CFD simulations of hemodynamics. RESULTS: Three examples of patient-specific models are presented: an anterior communicating artery aneurysm, a basilar tip aneurysm, and a model of an entire circle of Willis with five coincident aneurysms. The method is evaluated with a numeric phantom of an aneurysm in the anterior communicating artery. CONCLUSION: These examples show that this new technique can be used to create merged network numeric models for CFD modeling. Furthermore, intra-aneurysmal flow patterns are influenced strongly by merging of the two inflow streams. This effect decreases as distance from the merging streams increases.     

多层螺旋CT血管成像诊断颅内动脉瘤的价值

目的:探讨多层螺旋CT血管成像诊断颅内动脉瘤的价值。材料和方法:对比分析21例颅内动脉瘤的多层螺旋CT血管成像(MSCTA)和数字减影血管成像(DSA)的表现。结果:21例中,MSCTA发现21个动脉瘤,DSA发现20个动脉瘤,其中1例双侧动脉瘤,DSA只发现1侧,另1例MSCTA及DSA均未发现病变;21个动脉瘤中18个为圆形或类圆形,3个为不规则形,平均最长径为6.9mm(2.2~15mm);21个动脉瘤1个位于后交通动脉,2个位于基底动脉,5个位于大脑前动脉,5个位于大脑中动脉,8个位于前交通动脉。结论:MSCTA对颅内动脉瘤的诊断具有较高价值,可以作为外科治疗或介入治疗颅内动脉瘤的筛选方法。     

Computational fluid dynamics modeling of intracranial aneurysms: effects of parent artery segmentation on intra-aneurysmal hemodynamics

PURPOSE: The purpose of this study is to show the influence of the upstream parent artery geometry on intraaneurysmal hemodynamics of cerebral aneurysms. METHODS: Patient-specific models of 4 cerebral aneurysms (1 posterior communicating artery [PcomA], 2 middle cerebral artery [MCA], and 1 anterior communicating artery [AcomA]) were constructed from 3D rotational angiography images. Two geometric models were constructed for each aneurysm. One model had the native parent vessel geometry; the second model was truncated approximately 1 cm upstream from the aneurysm, and the parent artery replaced with a straight cylinder. Corresponding finite element grids were generated and computational fluid dynamics simulations were carried out under pulsatile flow conditions. The intra-aneurysmal flow patterns and wall shear stress (WSS) distributions were visualized and compared. RESULTS: Models using the truncated parent vessel underestimated the WSS in the aneurysms in all cases and shifted the impaction zone to the neck compared with the native geometry. These effects were more pronounced in the PcomA and AcomA aneurysms where upstream curvature was substantial. The MCA aneurysm with a long M1 segment was the least effected. The more laminar flow pattern within the parent vessel in truncated models resulted in a less complex intra-aneurysmal flow patterns with fewer vortices and less velocity at the dome. CONCLUSIONS: Failure to properly model the inflow stream contributed by the upstream parent artery can significantly influence the results of intra-aneurysmal hemodynamic models. The upstream portion of the parent vessel of cerebral aneurysms should be included to accurately represent the intra-aneurysmal hemodynamics.     

颅内宽颈动脉瘤的血管内治疗33例分析

目的总结应用颅内支架或球囊辅助技术治疗颅内宽颈动脉瘤的体会。方法应用颅内支架或球囊辅助瘤颈成形术结合Microplex弹簧圈栓塞治疗颅内破裂宽颈动脉瘤33例。动脉瘤位于前交通动脉8例,后交通动脉19例,大脑中动脉3例,基底动脉顶端3例。结果以支架辅助治疗的19例动脉瘤中13例完全致密填塞,4例填塞90％以上,2例大部填塞（70％～90％）。以球囊辅助治疗的14例动脉瘤中9例完全致密填塞,3例填塞90％以上,2例大部填塞。结论支架或球囊辅助治疗颅内宽颈动脉瘤是安全、有效的方法,两种方法各有优缺点,应根据动脉瘤的具体情况来选择采用支架或球囊治疗。     

颅内交通动脉瘤与Willis环血流动力学变化的关系

目的；探讨颅内交通动脉瘤与Willis环血流动力学变化的关系。资料与方法，回顾性分析199例数字减影脑血管造影资料。结果前交通动脉瘤，A1优势征多见；后交通动脉瘤，非基底动脉共血与基底动脉供血比较无差异。结论：颅内前交通动脉瘤的形成与Willis前环的血流动力学变化有关，后交通动脉瘤与Willis后环的血流动力学变化尚未见明显关系。     

Flow changes after endovascular treatment of a wide-neck anterior communicating artery aneurysm by using X-configured kissing stents (cross-kissing stents) technique

Endovascular treatment for a wide-neck anterior communicating artery (AcomA) aneurysm remains technically challenging. Stent-assisted embolization has been proposed as an alternative of treatment of complex aneurysms. The X-configuration double-stent-assisted technique was used to achieve successful coiling of wide-neck AcomA aneurysm. Implanted stent can alter intra-arterial flow. Follow-up angiograms 4 months later showed flow changes due to used X-technique of stents implantation and filling of the anterior cerebral artery from the opposite internal carotid artery.