脑血循环障碍的病理生理基础

脑血循环的解剖生理学脑血循环由颈内动脉和椎基底动脉供应,前者供应大脑前2/3的血管,后者供应大脑后1/3以及脑干、小脑,由二侧之后交通动脉联结。在脑底形成基底动脉环。脑血管功能上有效的侧支供血主要来自脑基底动脉环,其次为颈外一颈内动脉间的连络(如面动脉和限动脉间),软脑膜的交通支,及大脑前、中、后动脉间的皮质吻合支,很多情况下对脑梗塞的发生及减少梗塞的范围起一定作用。大脑中动脉皮质支于矢状沟旁区大脑前动脉的肼胝体缘支吻合,该区称为“边缘区”,在     

直接联合间接血管重建术治疗缺血型烟雾病疗效观察

目的 观察颞浅动脉-大脑中动脉分支吻合术联合脑-硬脑膜-肌肉血管融合术在缺血型烟雾病中的治疗作用.方法 回顾分析2009年3月至2011年12月在我院接受颞浅动脉-大脑中动脉分支吻合术联合脑-硬脑膜-肌肉血管融合术治疗的21例缺血型烟雾病患者的临床资料.其中5例接受同侧颞浅动脉-大脑中动脉2支血管吻合,16例接受同侧颞浅动脉-大脑中动脉单支吻合.结果 21例患者术中荧光造影显示吻合口全部通畅.16例术后1周内复查了CT血管成像,5例复查全脑数字减影血管造影术,其中20例显示吻合血管通畅,l例吻合血管闭塞.21例缺血型患者中有10例患者的运动或感觉障碍等症状在术后第2天即有明显改善.1例失语患者症状消失,4例头晕,4例头痛患者症状减轻.有2例患者临床症状较术前无明显改变.结论 应用直接联合间接血管重建术能明显改善缺血型烟雾病患者缺血症状.     

手术治疗烟雾病的困窘

Moyamoya(烟雾)病是一种特殊发展过程中的脑血管闭塞性疾病，有多种侧枝循环类型。该病手术方法有二，即直接吻合血管和间接非吻合血管再生法，前者有STA-MCA(颞浅动脉-大脑中动脉)吻合术、0A-MCA(枕动脉-大脑中动脉)吻合术和静脉移植术，后者则有EMS(脑肌联合血管术)、EDAS(脑硬膜动脉联合血管术)及其它方法。     

烟雾病3例的磁共振诊断

烟雾病指双侧颈内动脉（ICA）末端及大脑前、中动脉起始部进行性狭窄或闭塞，以颅底软脑膜和穿通动脉形成细小密集的吻合血管网为特征的慢性脑血管闭塞性疾病，该病血管造影呈烟雾状，故又称“烟雾病”。病因不明确，以往需用脑血管造影来明确诊断，现在MRI和MRA的发展不仅可对此病定性诊断．还可了解因动脉狭窄或闭塞继发的脑实质病变。已成为该病的首选方法。     

烟雾病双侧颈内动脉闭塞1例

<正>患者,女,68岁。因发作性头晕4年,再发1个月入院。于4年前无明显诱因出现头晕,视物旋转、黑蒙,给予静脉滴注血栓通、奥拉西坦等药治疗后,头晕症状缓解。近1月来再次发作,以"椎-基底动脉供血不足、2型糖尿病"收住神经科。彩色多普勒超声显示:双侧颈总动脉膨大部多发斑块形成,内径、血流速尚可;右侧颈内动脉闭塞;双侧颈外动脉多发斑块形成,内径增宽、血流速偏高,阻力指数减低。数字减影血管造影(DSA)及CT血管造影(CTA)显示:双侧颈内动脉闭塞,颈外动脉通过广泛脑膜吻合支入颅供应颅内,双侧大脑前动脉、大脑中动脉缺如,颅底较多细小动脉呈烟雾状     

Onxy栓塞硬脑膜动静脉瘘1例

<正>患者,男,62岁,因双眼视物模糊加重伴耳鸣2年、左眼视力下降5月、血压增高2年到笔者所在医院检查。门诊MRI检查:双侧大脑半球表面及环池、枕大池多处血管扩张。以"颅内血管畸形"收入院。为防止病情进一步加重,实施全脑血管造影术及动静脉瘘栓塞术。麻醉成功后,应用Seldinger技术穿刺右侧股动脉,行各血管造影示:双侧脑膜垂体干、双侧脑膜中动脉、双侧枕动脉远端分支破入     

猫眼视盘微血管铸型研究

目的 利用血管铸型技术观察猫眼视盘微血管的三维结构。方法 采用甲基丙烯酸甲酯／丙烯酸甲酯分别经颈总动脉灌注家猫8例16眼。解剖显微镜及扫描电镜观察。结果 猫眼视神经中央无大血管贯穿,视网膜及脉络膜供应血管由睫状后动脉分支形成,视盘表面放射状毛细血管由睫状视网膜动脉分支构筑。视盘血管由睫状后动脉形成的鞘膜动脉网和脉络膜动脉直接分支供应,睫状后动脉在鼻侧形成半环状样结构。结论 猫眼无中央血管系统及完整的秦氏环,睫状后动脉是视盘血管的主要来源。猫眼视盘微血管构筑与人眼相似．     

基底动脉尖综合征

基底动脉尖(TOB)综合征:是指基底动脉顶端血液循环障碍引起的一组临床综合征,由于其发病症状多样,特异性不突出,且临床预后多不良,及早发现及早期干预,对病情估计及提高就治率有积极的临床意义. 1 局部解剖 基底动脉尖(TOB)是基底动脉顶端2cm范围内的五条血管即2条大脑后动脉、两条小脑上动脉以及基底动脉顶端,形成一个"干"字.大脑后动脉是基底动脉的终末支,绕过大脑脚跨过小脑幕切迹,最后达距状裂,供应枕叶内侧面和颞叶的底面,还发出许多小支,供应丘脑的内测部、大脑脚的内侧部及外侧膝状体.     

颅外椎动脉和侧支吻合的解剖学研究及其临床意义

目的 :观察颅外椎动脉段及其侧支吻合情况 ,并探讨其临床意义。方法 :在 4 0具 80侧经防腐处理的成人尸体标本上 ,观察颅外椎动脉各段的走行、分支及其侧支吻合情况 ,测量各段起点的外径、长度。结果 :前两段左侧椎动脉起点直径大于右侧 ,左右比较有显著性差异 (P <0 .0 5 ) ;而各段长度比较无显著性差异 (P >0 .0 5 ) ;椎动脉与颈动脉间有广泛的吻合 ,一般为细小的肌支吻合 ,椎动脉与枕动脉间的血管吻合比较恒定。结论 :颅外椎动脉各段测量结果对椎动脉重建术有重要参考价值 ;其侧支吻合是椎动脉代偿机制的重要解剖学基础之一 ,在椎基底动脉供血不足发病中有重要的意义     

经脉络膜裂房部至四叠体池的显微解剖

目的：研究经脉络膜裂房部至四叠体池的解剖特点,为经脉络膜裂入路治疗四叠体池周围区域病变提供解剖学依据。方法经10％甲醛固定的完整成人湿性尸头标本10例（20侧）,观察脉络膜裂房部的神经血管结构,显微镜下模拟经脉络膜裂房部到四叠体池手术入路。结果脉络膜裂房部是位于侧脑室房部内侧壁穹窿伞和丘脑枕之间的一条自然裂隙,其后缘为丘脑枕处,此处到侧脑室三角区后缘的距离为（15苘．9±3．3）mm,到中线的垂直距离为（21．6±2．8）mm,距室间孔后缘的脉络膜裂起点的裂长度为（31．4±3．5）mm。经此裂隙可进入四叠体池,池的前壁内侧为松果体和四叠体,脉络膜裂房部后缘到松果体的距离为（10．8±2．1）mm。脉络膜后外动脉通过脉络膜裂进入侧脑室,分布于颞角后部、房部、体部后部的脉络丛,脉络膜后内动脉经四叠体池进入三脑室顶壁,分布于中间帆内的脉络丛。房内侧静脉为位于侧脑室房部和枕角内侧壁呈放射状向脉络膜裂汇聚的一组静脉,经穹窿内侧到达四叠体池,汇入大脑内静脉或大脑大静脉。模拟经脉络膜裂房部的手术入路,可显露的范围包括四叠体池和同侧环池的后部,对池内走行的大脑后动脉（ P2和P3）、基底静脉等众多血管结构显露良好,分离这些血管可以显露位置较深的松果体,而对上下丘显露十分困难。结论脉络膜裂房部及四叠体池周围神经血管结构复杂,熟悉其解剖特点十分重要,经脉络膜裂入路为治疗四叠体池周围区域病变提供了一条良好的路径。     

乳头体的动脉及其临床意义

目的研究乳头体的动脉,为血管性老年痴呆提供形态资料。方法在50例人脑标本,用手术显微镜观察乳头体动脉来源,分支,分部,组织切片方法研究来源动脉病理改变对乳头体动脉的影响。结果乳头体依形态可分为Ⅰ、Ⅱ、Ⅲ、Ⅳ型等几种类型,动脉的主要来源为后交通动脉和大脑后动脉双来源型的占38%。60～80岁老年人乳头体的来源动脉有动脉粥样硬化的占88%。可见异常粗大,大脑后动脉、基底动脉和颈内动脉骨化的脑血管样本2例,致乳头体管腔狭窄阻塞。结论乳头体动脉位于后交通动脉和大脑后动脉的边缘区,血供较差,动脉钙化可使小动脉阻塞,可能是导致老年痴呆的原因之一。     

Pharmacological characterization of postjunctional alpha-adrenoceptors in cerebral arteries from the sheep.

1. The responsiveness to noradrenaline was characterized in cerebral arteries from the sheep, since this species was large enough to permit a comparison of arteries from different parts of the cerebral vasculature. 2. Noradrenaline caused contraction of the basilar artery, middle cerebral artery and small pial arteries by stimulation of alpha 1-adrenoceptors. 3. The maximum contraction to noradrenaline was small in the basilar artery (28% of the 5-hydroxytryptamine (5-HT) maximum) but larger in the middle cerebral artery (78% of the 5-HT maximum) and pial artery (92% of the 5-HT maximum) of the sheep. 4. Cocaine (10 microM) potentiated noradrenaline-induced contractions in the sheep middle cerebral artery but not in the sheep basilar artery. 5. The noradrenaline contraction, relative to the 5-HT contraction, was not affected by removal of the endothelium in either the sheep basilar or middle cerebral artery. 6. The results showed a variation within the sheep cerebral vasculature in the response to noradrenaline which cannot be explained by regional differences in alpha-adrenoceptor subtypes, noradrenaline uptake mechanisms or endothelial function.     

Vasodilator effects of KRN2391, levcromakalim and 3-morpholino-sydnonimin in human pial and omental arteries

The vasodilator action of KRN2391 (10 nM-10 microM), a combined ATP-sensitive potassium channel (KATP) opener and organic nitrate, was investigated in human pial and omental arteries. Previous animal studies have suggested that opening of KATP and activation of guanylate cyclase may contribute to varying extents to the vasodilator action of KRN2391, depending on the origin and size of the vascular preparation. Vasodilator responses were studied in isolated vascular segments (diameter 0.4-0.8 mm) pre-contracted with endothelin-1 in the presence or absence of glibenclamide (inhibitor of KATP), LY83583 (inhibitor of guanylate cyclase), zaprinast (inhibitor of cyclic GMP phosphodiesterase V) and NG-nitro-L-arginine (inhibitor of nitric oxide synthase). KRN2391 induced concentration-dependent vasodilator responses of similar potency in arteries from the two vascular regions. While glibenclamide (1 microM) had no effect in omental arteries, this compound produced a tenfold rightwards shift of the concentration-response curve for KRN2391 in pial arteries without affecting the maximal response (Emax). LY83583 (10 microM), zaprinast (10 microM) and NG-nitro-L-arginine (0.1 mM) all failed to affect the vasodilator responses to KRN2391 significantly in either artery. However, in ring segments of rat aorta LY83583 displaced the concentration-response curve for the nitric oxide donor 3-morpholino-sydnonimin (10 nM-0.1 mM) to the right, while zaprinast produced a leftwards shift. The prototype KATP opener levcromakalim (0.01-10 microM) elicited a larger relaxation in pial (Emax 80+/-6%) than in omental (Emax 47+/-13%) arteries, whereas 3-morpholino-sydnonimin produced a smaller relaxation in pial (Emax 50+/-18%) than in omental (Emax 90+/-4%) arteries. These results suggest that the vasodilator response to KRN2391 is mediated by KATP in human cerebral arteries, but dependent on neither KATP nor guanylate cyclase in human omental arteries. The results with levcromakalim and 3-morpholino-sydnonimin indicate that opening of KATP may be a more effective mechanism of vasodilatation in pial than in omental arteries from man, whereas the reverse appears to be true for guanylate cyclase activation.     

MSCTA对后循环缺血椎-基底动脉粥样斑块的诊断价值

目的探讨多排螺旋CT血管造影(MSCTA)对后循环缺血的椎-基底动脉粥样斑块和狭窄程度的诊断价值。方法对53例后循环缺血患者行MSCTA检查。应用原始图像、MIP和CPR图像寻找斑块,探讨椎-基底动脉粥样斑块发生部位、数量、成分、性质、动脉狭窄程度。结果53例中,共发现83处斑块。其中,椎动脉颅内段、三段、二段、起始段、基底动脉、大脑后动脉分别35处、9处、4处、16处、16处、3处。软斑块41处(49.4%),混合斑块18处(21.7%),钙化斑块24处(28.9%)。轻、中、重度狭窄、闭塞分别29处,51处、15处、10处。斑块表面不规则15处,斑块溃疡9处。结论 MSCTA可充分显示后循环缺血的椎-基底动脉粥样斑块发生情况和动脉狭窄程度,为其诊断和治疗提供可靠的依据。     

发生囊状动脉瘤的颅内动脉血管分叉的角度研究

目的探讨囊状动脉瘤与颅内动脉血管分叉的角度关系。方法随机选取后交通动脉显影(包括胚胎型)且有动脉瘤者30例作为试验组,另选取后交通动脉显影(包括胚胎型)且无动脉瘤者30例作为对照组,均予三维(3D)脑血管造影观察颈内动脉后交通动脉段及后交通动脉间夹角,比较2组血管分叉的角度差异。结果试验组主流出道与流入道偏角、小分支与流入道偏角及分支夹角均大于对照组,差异均有统计学意义(P<0.01)。结论动脉瘤的发生发展与颈内动脉后交通动脉分支段和后交通动脉之间夹角变大有关。     

Effects of the new calcium antagonist 2-nitratopropyl 3-nitratopropyl 2,6-dimethyl-4-(3-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate on cerebral circulation in cats

Effects of CD-349 (2-nitratopropyl 3-nitratopropyl 2,6-dimethyl-4-(3-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate) on cerebral circulation were studied in 10 cats. The cats were fixed in a stereotactic head-holder, and two burr holes were made at 3-mm intervals over the left parietal cortex. Through one cranial window, the pial artery and vein diameters were measured continuously by a newly developed videocamera system in conjunction with a width analyzer, and the other one was used for measurement of cerebral blood volume (CBV). The pial artery (141 +/- 14 micron) was dilated by 16.6 +/- 4.9% (p less than 0.01) 1 min and 24.8 +/- 5.1% (p less than 0.01) 5 min after the CD-349 injection. The pial vein (101 +/- 20 micron) was also dilated with the percent increase of the diameter being 11.4 +/- 4.0% (p less than 0.01) 1 min and 11.3 +/- 4.9% (p less than 0.05) 5 min after the CD-349 administration. The CBV was also increased. The mean arterial blood pressure was decreased by 39.8 +/- 7.3 mmHg (p less than 0.01) 1 min and 34.4 +/- 5.5 mmHg (p less than 0.01) 5 min after drug injection. Thereafter, the blood pressure gradually returned to the pre-drug level. Form these results it is suggested that CD-349 exerts direct vasodilatory action via inhibition of calcium influx across vascular cell membranes into cerebral vessels.     

Prostaglandin metabolism and prostacyclin in cerebral vasospasm

1. Contractions of isolated human pial arteries, induced either by exposition to hemorrhagic cerebrospinal fluid (CSF) from patients with subarachnoid hemorrhage and cerebral vasospasm or by exposition to noradrenaline, were markedly augmented after preincubation of the vessel segments with the cyclooxygenase inhibitor indomethacin, while serotonin-induced contractions were unaffected. 2. Prostacyclin relaxed human pial arteries contracted by either PGF2 alpha, noradrenaline, serotonin or hemorrhagic CSF. The same though less marked effects were obtained with 6-keto-PGE1. 3. The results support the contention that an intact vascular prostacyclin synthesis is important for the maintenance of a normal cerebrovascular tone, and that disturbances of the prostaglandin metabolism may be a prerequisite for the development of arterial spasm after aneurysmal subarachnoid hemorrhage. Tentatively. 4. a prostacyclin deficiency may be involved in the pathogenesis of delayed cerebral vasospasm after subarachnoid hemorrhage.     

ELECTRICAL FIELD STIMULATION IN CEREBRAL AND PERIPHERAL ARTERIES: A CRITICAL EVALUATION OF THE CONTRACTILE RESPONSE

• 1 Electrical field stimulation with recording of isometric contraction in vitro was carried out on small circular segments of pial arteries, in comparison with peripheral arteries from several regions of rat, rabbit, cow, cat, dog and man.
• 2 It was found that tetrodotoxin (TTX)-resistant contractions were obtained more readily in pial arteries of various species, including man, than in peripheral arteries of similar size. In fact, it was not possible to obtain a purely neurogenic response — without a TTX-resistant change in tone — in any pial vessels tested.
• 3 The stimulation parameters that induced TTX-resistant contraction in pial arteries were similar to those weak parameters that could reveal a purely neurogenic response in certain other arteries, such as rabbit central ear artery and rabbit and feline mesenteric arteries. In these arteries, release of noradrenaline (NA) onto postjunctional α-adrenoreceptors was found to be fully responsible for the contraction. The contractile response could be considerably potentiated by blockade of neuronal and extraneuronal uptake, prejunctional α-receptor blockade, and 4-aminopyridine (4-AP)-induced enhancement of transmitter release. Addition of compounds to prevent oxidation of released NA (EDTA by its ability to bind metal ions, and ascorbic acid-glutathione, which prevents formation of free radicals) did not enhance the neurogenic response.
• 4 However, not even under any of these conditions was it possible to reveal a purely neurogenic response in cerebral arteries. Only TTX-resistant contractions, likely to be due to direct smooth muscle activation, were obtained. The explanation may be morphological differences related to myogenic propagation, probably together with poorly sensitive α-adrenoreceptors, in these pial arteries. The situation was further complicated by the fading of the TTX-resistant contraction which often occurred upon repeated stimulation.
• 5 Therefore, acceptance of partial blockade by TTX as a criterion for a neurogenic response in cerebral vessels, as by several previous investigators, may lead to misinterpretation of the true nature of the response. Hence, when studying neurogenic mechanisms in vitro in these arteries, parameters other than vascular tone should be recorded in conjunction with electrical field stimulation, such as registration of junction potentials and measurements of released transmitter.

     

The in vivo effect of adrenomedullin on rat dural and pial arteries

Adrenomedullin is related to the calcitonin gene-related peptide (CGRP) family and is present in cerebral blood vessels. It may be involved in migraine mechanisms. We measured the change in dural and pial artery diameter, mean arterial blood pressure and local cerebral blood flow flux (LCBF(Flux)) after intravenous (i.v.) infusion of adrenomedullin. The study was performed in the presence or absence of the CGRP1 (calcitonin-receptor-like-receptor (CALCRL)/receptor activity-modifying protein-1 (RAMP1)) receptor antagonists BIBN4096BS, CGRP-(8-37) and the adrenomedullin receptor antagonist adrenomedullin-(22-52). I.v. infusion of 15 mug kg(-1) adrenomedullin (n=8) induced dilatation of dural (32+/-7.5%) and pial (18+/-5.5%) arteries, a reduction in mean arterial blood pressure (19+/-3%) and an increase in LCBF(Flux) (16+/-8.4%). The duration of the responses was 25 min for the dural artery, while the response of the pial artery lasted for 15 min. The CGRP1-receptor antagonists BIBN4096BS and CGRP-(8-37) and the adrenomedullin receptor antagonist adrenomedullin-(22-52) significantly inhibited the effect of adrenomedullin (n=7, P<0.05 for both arteries) on dural and pial artery diameter and mean arterial blood pressure. No significant inhibition of LCBF(Flux) was found. The antagonist alone had no effect on mean arterial blood pressure or LCBF(Flux). In conclusion, we suggest that adrenomedullin in the rat cranial circulation dilates dural and pial arteries, reduces mean arterial blood pressure and increases LCBF(Flux), probably via a CGRP1-receptor.     

大脑前动脉皮质支分布区域梗死所致的偏瘫、缄默或淡漠

目的：提高对大脑前动脉皮质支分布区域梗死的临床认识。方法：本文结合3例患者的临床表现及CT影像学特点进行了回顾性调查分析。结果：3例大脑前动脉皮质支分布区域的额叶矢状窦旁皮质、额叶内侧面包括扣带回前部、中央前回内侧面、运动前区和辅助运动区梗死的病人，出现了以对侧偏身严重瘫痪、精神缄默或淡漠为突出的临床症状。结论：大脑前动脉皮质支闭塞，可以造成对侧偏瘫、精神缄默或淡漠症候群。