|
Intracranial dural arteriovenous fistulas (dAVFs) are a group ofacquired pathological vascular malformations that are defined by anabnormal connection between an artery and a vein, bypassing thecapillary bed. The shunting that is confined to the dura is supplied bybranches of the external carotid artery, tentorial branches of theinternal carotid artery, meningeal branches of the vertebral artery,and rarely, the pial branches of the cerebral arteries. 颅内硬脑膜动静脉瘘是一种由动脉和静脉之间绕过毛细血管床而异常连接的获得性病变。硬脑膜局部是由颈外动脉的分支,颈内动脉的小脑幕支,椎动脉的脑膜支和极少部分脑动脉的软膜支供血。
The dAVFs and more specifically the fistulas themselves are locatedwithin the walls of the dural venous sinus. They may develop due todural venous thrombosis, infection, previous surgery, or trauma,although many cases are idiopathic. Inflammatory changes fromthese conditions can cause angiogenesis, demonstrated by highconcentrations of vascular endothelial growth factor (VEGF) foundnear fistulas. A subset of these fistulas directly connects to a cortical(leptomeningeal) vein. 硬脑膜动静脉瘘（ dAVFs），确切地说瘘管本身位于硬脑膜静脉窦壁，其形成可能是由于硬脑膜静脉窦的血栓、感染、前期的手术或外伤, 但多数情况下是自发性的。炎症可以使瘘管周围聚集高浓度的血管内皮生长因子，最终导致血管再生。这些瘘管的一部分可直接与大脑皮层（或软膜）静脉相通。
Some researchers have also proposed embryologic theories thatimplicate abnormal recanalization of the primitive direct connectionsbetween the arteries and veins in response to an inflammatoryreaction or venous sinus occlusion. 一些研究者也提出了胚胎发育理论，其涉及动静脉的炎性反应或静脉窦闭塞引起的动静脉胚胎期原始连接的异常再通。
The frequency of arteriovenous malformations (AVMs) in the generalpopulation is approximately 0.15%, and an estimated 10% to 15% ofthese are dAVFs. Multiple classification systems for dAVFs exist.These systems are based on the lesions’ venous drainage patternsas this factor dictates the behavior of the lesion. Djindjian andThe Neurosurgical Atlas by Aaron Cohen-Gadol, M.D.Merland first classified dAVFs according to their venousangioarchitecture in 1978. In 1995, Cognard further classified bothcranial and spinal arteriovenous fistulas according to their venousoutflow with prognostic and treatment implications. 动静脉畸形在普通人群中的发病率约为0.15%，其中大约10% ～15%为dAVFs。硬脑膜动静脉瘘具有多个分类系统，这些分类系统都是基于病变的引流静脉模式而制定，从而决定了病变的表现形式。1978年，Djindjian和Merland根据静脉血管架构首次将dAVFs进行分型。1995年，Cognard根据dAVF的静脉流向相关的预后因素及治疗并发症，进一步将颅内和脊髓的dAVF进行分类。 Borden simplified the Cognard classification, emphasizing that themajor factor in predicting an aggressive clinical course is thepresence of cortical venous drainage. Unlike venous sinuses, corticalveins are not protected by the dura and cannot withstand arterialpressures. Therefore, dAVFs with cortical venous drainage (Bordentypes II and III) have a higher risk of rupture and hemorrhage. Thehemorrhage from dAVFs can be parenchymal, subarachnoid, orsubdural in nature. Borden 简化了Cognard分类,强调皮层引流静脉是预测一个临床诊疗结局的主要因素。不同于静脉窦，皮层静脉不受硬脑膜的保护，不能承受动脉压。因此，具有皮层静脉返流(Borden分型 II和III型)的硬脑膜动静脉瘘可能有更高的破裂或出血的风险，其出血特点可能为脑实质出血，蛛网膜下腔出血或硬膜下出血。
表1: 硬脑膜动静脉瘘分型
Intracranial hemorrhage and neurologic deficit is likely in 2% of theBorden classification type I, 39% of type II, and 79% of type III dAVFs. 硬脑膜动静脉瘘Borden分型I 型其脑出血和神经功能缺陷约占2%，II 型约39% ，III 型约占79%。
The most common presentation of a low-grade (Borden Type I) dAVFis pulsatile tinnitus, which may be auscultated as a bruit by theclinician. Other presentations include headaches or deterioratingmentation from the effects of venous congestion. Hydrocephalus oredema may occur as a result of an obstructive outflow in a largevenous varix or from impaired cerebrospinal fluid (CSF) drainagecaused by increased venous sinus pressures. 低级别的硬脑膜动静脉瘘(Borden I型)最常见的一个临床表现是搏动性耳鸣,听诊时可出现杂音。其他症状包括头痛或静脉淤血导致的恶化性精神症状。大的静脉扩张或静脉窦压力增加引起的脑脊液回流受阻都可导致脑积水或水肿。
The natural history of dAVFs without cortical venous drainage is fairlybenign; only 1% of these lesions convert from Borden types I and II toBorden type III. However, there is a 45% mortality rate over 4 yearsamong patients with cortical venous drainage, a 19.2% intracranialhemorrhage rate per year and 10.9% new neurologic deficit rate peryear. For patients who present with hemorrhage, the rehemorrhagerate is 35% within the first 2 weeks of the initial ictus. Venousstenosis is a concerning sign and suggests the risk of transformationto a more malignant one or the loss of venous access. 无皮层静脉回流的硬脑膜动静脉瘘的自然史属于良性病变。硬脑膜动静脉瘘仅有 1% 会从Borden I型 和 II型转变为Borden III型。然而，有皮层静脉返流的硬脑膜动静脉瘘4年以上的死亡率为45%，每年其脑出血率为19.2%、神经功能缺损为10.9%。出现脑出血的患者，其初次出血后2周以内，再出血率为35% 。静脉狭窄是一个让人担忧的问题，其提示病变的恶化或静脉通道的减少。
The surgical approach to many dAVFs may be associated withsignificant blood loss, and endovascular therapy is therefore thetreatment of choice for most intracranial locations, with a few notableexceptions, such as the ethmoidal and petrosal/tentorial dAVFs.These operative dAVFs are associated with higher risks ofhemorrhage than fistulas in other sites. I will review the subtypes ofintracranial dAVFs before discussing their surgical management. 硬脑膜动静脉瘘手术方式的选择与失血量相关联，因此,血管内介入治疗适用于大部分的病变，但是，对于筛骨、岩骨或小脑幕区的硬脑膜动静脉瘘不适用。硬脑膜动静脉瘘术中大出血的概率可能大于其他部位的动静脉瘘。在讨论手术技巧之前，我们将回顾颅内硬脑膜动静脉瘘的几种亚型。
Classifications and Operative Considerations 分类及手术注意事项 The majority (60%) of intracranial dAVFs are found along thetransverse-sigmoid junction, followed by the cavernous sinus and thesuperior sagittal sinus. The lesions of the transverse and sigmoidjunction are largely treated endovascularly because there is a directtransvenous route that allows for occlusion of the fistula or thevenous sinus. 目前发现大多数（60%）颅内硬脑膜动静脉瘘位于横窦和乙状窦的交汇处，其次位于海绵窦和上矢状窦。横窦和乙状窦的交汇处的硬脑膜动静脉瘘主要应用血管内介入治疗，这样可以直接经静脉途径闭塞瘘管或静脉窦。 Figure 1: This illustration demonstrates the location andincidence of the most common types of intracranial dAVFs.Ethmoidal and petrosal fistulas are most favorable formicrosurgical ligation, unlike other dAVFs, which are moreamenable to endovascular therapy. 图 1: 上图展示了最常见的颅内硬脑膜动静脉瘘几种类型的位置和发病率。筛骨和岩骨处的动静脉瘘适合显微外科结扎，而其他类型的硬脑膜动静脉瘘更适合血管内介入治疗。
The venous sinuses may be occluded through embolization as longas there is an alternate collateral venous drainage route. Forinstance, in the case of a left transverse-sigmoid dAVF, a patenttorcula allows for occlusion of the left transverse sinus (as long as thevein of Labbé is spared). Similarly, the cavernous sinus often must becompletely embolized to cure a carotid cavernous fistula (CCF), andvenous drainage is rerouted to the sphenoparietal sinuses and theSylvian veins that join the superior sagittal sinus. 在具有侧支回流静脉的前提下，通过血管内介入栓塞可以使静脉窦闭塞。例如，在左侧横窦和乙状窦的交汇处的硬脑膜动静脉瘘中，可以通过血管内治疗闭塞左侧横窦( 只要Labbé静脉未受损)。同样，治疗颈内动脉海绵窦瘘必须完全栓塞海绵窦，其静脉回流可经蝶顶窦和侧裂静脉重新回流至上矢状窦。
Transarterial embolization may be used to reach the venous side ofthe fistula. However, it is necessary to embolize the venous sidebecause occlusion of the arteries alone will result in recanalization ofthe fistula via the smaller fistulous feeders, not initially detectable oramenable to embolization. 经动脉途径栓塞可到达瘘的静脉端。但是必须同时栓塞静脉端，仅栓塞动脉端可能会导致瘘的再通。
Diagnosis and Evaluation 诊断与评价
Computed tomography (CT) or magnetic resonance imaging (MRI)may demonstrate diffusely engorged venous congestion of thedraining veins or the presence of a dilated superior ophthalmic veinin a patient with a cavernous-carotid fistula. The characteristicangiographic feature of dAVFs is premature appearance ofintracranial veins or venous sinuses during the arterial phase. 在颈动脉海绵窦瘘的患者中，计算机断层扫描(CT)或磁共振成像(MRI)能够显示过度充盈的回流静脉或扩张的眼上静脉。血管造影的特征性表现是在动脉相上颅内静脉或静脉窦早显。
Magnetic resonance angiography (MRA) or CT angiography (CTA)may not detect a dAVF. Three-dimensional MRA may be useful, buttraditional catheter or digital subtraction angiography remains thegold standard for the diagnosis and management of dAVFs. Theangiogram should evaluate both internal carotid arteries, bothexternal carotid arteries, and both vertebral arteries. A thoroughangiogram is mandatory because internal carotid or vertebral arteryinjections alone may lead the physician to overlook a large dAVF fedby the external carotid circulation. In addition, even a simple dAVFmay recruit multiple feeding arteries from different circulations ofthere could be multiple dAVFs. 磁共振血管成像(MRA)或CT血管成像(CTA)可能不会发现硬脑膜动静脉瘘。三维磁共振血管造影可能有所帮助,但传统的导管或数字减影血管造影术仍然是诊断与治疗硬脑膜动静脉瘘的金标准。血管造影应同时评估颈内动脉,颈外动脉和椎动脉。血管造影应是全方位的,因为仅颈内动脉或椎动脉造影可能导致医生漏诊由颈外动脉供血的硬脑膜动静脉瘘。此外,即使是一个简单的硬脑膜动静脉瘘也可能具有来自不同供血动脉的多个滋养动脉。
The nidus of a dAVF is the center of arteriovenous shunting and thesite of the dura where all feeding arteries converge to and the venousdraining channels diverge from. Although multiple draining veins andintimidating engorged varices and veins are apparent, a single largedraining vein is most often the main draining site of the fistula. 硬脑膜动静脉瘘的病灶处是动静脉分流的中心，也是硬脑膜上所有滋养动脉汇集处，同时是引流静脉转向的部位。 尽管存在大量的引流静脉和过度充盈扩张的静脉，但单个粗大的引流静脉通常是瘘最主要的引流部位。 The presence or absence of cortical venous drainage, venous sinusocclusion, direction of flow (anterograde versus retrograde) in thedural venous sinuses, and the normal venous drainage anatomy ofthe surrounding cortices must be evaluated. 所以，必须评估皮层引流静脉的存在与否，静脉窦闭塞，硬脑膜静脉窦的引流方向(顺行或逆行) 以及正常的皮层周围引流静脉的解剖。
I carefully study the venous phase of the angiogram to ensure thatnormal brain is not draining into an indispensible vein (vein of Labbe)that is joining the arterialized target vein. If that is the case, thenonarterialized vein(s) should be carefully spared during thedisconnection of the arterialized ones. 仔细观察血管造影的静脉相以确定正常的大脑中血液没有引流入一个重要的静脉(Labbe静脉)，而是流入动脉化的目标静脉中。如果是这样, 在分离动脉化的静脉的过程中应该小心保留未动脉化的静脉。
Supratentorial Dural Arteriovenous Fistulas 幕上的硬脑膜动静脉瘘
The majority of superatentrial fistulas that are amenable to operativeintervention are ethmoidal and parasagittal dAVFs. 大多数能够手术干预的硬脑膜动静脉瘘是筛骨和矢状窦旁区的硬脑膜动静脉瘘。 Figure 2: An anteroposterior angiogram of the left externalcarotid artery (left) and a lateral angiogram of the left internalcarotid artery (right) demonstrate an ethmoidal dAVF that is fedby the anterior ethmoidal and falcine arteries and drains into anarterialized cortical vein associated with venous varices. 图 2: 左侧颈外动脉的正位片（左图）和左侧颈内动脉的侧位片（右图）展示了由筛前动脉和镰状动脉供血的引流入扩张的动脉化的皮层静脉的筛骨区硬脑膜动静脉瘘。
Ethmoidal fistulas are located at the anterior fossa floor and fed bythe anterior ethmoidal arteries, the dural branches of the ophthalmicartery, and the anterior falcine artery that arises from the ophthalmicartery. They may also recruit dural arterial supply via the anteriordivision of the middle meningeal arteries. They serve a fistulousconnection harboring pial vein(s)(olfactory and frontal veins) thatconnect at the base of the anterior fossa dura just under the frontallobe or medially into the falx. 筛骨的瘘管位于前颅窝底，其供血动脉是筛前动脉，眼动脉的脑膜支以及沿眼动脉上升的大脑镰前动脉，也可能通过脑膜中动脉的前支血供，它们互相连接到瘘管，隐藏连接在额极或大脑镰内侧的前颅窝底硬脑膜基底部软膜静脉 (嗅静脉和额静脉)。
Venous varices on the arterialized vein carry a significant risk ofhemorrhage, shown to be up to 57% in some series. Due to the pialnature of these veins, there is no practical transvenous route to reachthem. The transarterial route is through the ophthalmic artery,rendering transarterial embolization a risk for blindness. Surgicaltreatment, however, is technically easy and low risk and is describedin the chapter titled: Supratentorial Dural Arteriovenous Fistulas. 动脉化的静脉扩张具有明显的出血风险，在一些案例中其风险高达57%。由于这些静脉具有软膜的特征，经静脉途径血管内介入不能到达。而经动脉通路是通过眼动脉进行,其经动脉栓塞可能导致失明。在“幕上硬脑膜动静脉瘘”章节中提到的外科治疗则具有简单易行、低风险等优点。
Infratentorial Dural Arteriovenous Fistulas 幕下硬脑膜动静脉瘘 The majority of infratentorial dAVFs that are suitable to microsurgery are superior petrosal dAVFs. 多数适合显微手术的幕下硬脑膜动静脉瘘是岩骨区的硬脑膜动静脉瘘。 Figure 3: A lateral internal carotid artery (ICA) angiogramdemonstrates a tentorial/petrosal dAVF, supplied by the tentorialfeeders from the ICA and draining into the petrosal vein witharterialization of the posterior fossa veins. 图 3: 颈内动脉侧位造影片展示了小脑幕/岩骨的硬脑膜动静脉瘘，由颈内动脉的小脑幕支供血，将后颅窝区的静脉动脉化流入岩静脉。
Superior petrosal dAVFs are also difficult to access endovascularlyfrom either the arterial or venous side. They feed from the tentorialbranches of the internal carotid artery, such as the tentorial artery ofBernasconi and Casinari, the inferolateral trunk, and themeningohypophyseal trunk, as well as the external carotid branches,such as the middle meningeal and ascending pharyngeal arteries.They drain into the arterialized petrosal vein and produce largesupratentorial or infratentorial arterialized varices. These lesions areusually easily treated via clip ligation of the arterialized superiorpetrosal sinus through the retrosigmoid approach. This technique isdescribed in the chapter titled: Infratentorial Dural ArteriovenousFistulas 岩上的硬脑膜动静脉瘘通过血管内介入很难到达其动脉端或静脉端。他们的供血动脉来自颈内动脉的小脑幕动脉分支，如天幕动脉的下外侧干和脑膜垂体干；也有来自颈外动脉的分支，如脑膜中动脉和咽升动脉。它们流入动脉化的岩静脉中，形成大的幕上或幕下动脉化的扩张静脉。这些病灶可以经乙状窦后入路通过夹闭动脉化的岩上窦来治疗。此方法在“幕下硬脑膜动静脉瘘”这一章节中详细介绍。
A large venous varix associated with the fistula can cause trigeminalneuralgia by compression of the root entry zone of the trigeminalnerve. 大的扩张静脉可通过压迫三叉神经根入口区引起三叉神经痛。
Cavernous-Carotid Fistulas 颈内动脉海绵窦瘘
One unique type of intracranial dAVF is the cavernous-carotid fistula(CCF), a connection between the carotid artery and the cavernoussinus. This connection may be direct from the cavernous carotidartery itself, which is usually high-flow and due to trauma, or indirectfrom the arterial feeders from the internal or external carotid artery. 颈内动脉海绵窦瘘是颅内硬脑膜动静脉瘘的一个特殊类型，它是颈内动脉和海绵窦的相沟通。此类型可能是颈内动脉直接与海绵窦沟通，属于高流量瘘，常见于外伤；或者是颈内动脉或颈外动脉的分支动脉间接沟通引起。
CCFs are unique in their presenting ophthalmic symptoms, althoughthey can also present with symptoms of retrograde cortical venousdrainage. Initial symptoms include a proptotic, chemotic eye withincreased intraocular pressure (IOP). Glaucoma (IOP > 20) can leadto blindness, and is considered an urgent condition requiringtreatment. 颈内动脉海绵窦瘘虽然可以表现为皮层静脉逆行引流症状，但眼部症状是其特有症状。初期症状包括突眼,球结膜水肿与眼内压的升高。青光眼 (IOP > 20)可致失明, 需要尽快治疗。 CCFs may also present with third, fourth, or sixth cranial nervepalsies and are best treated through endovascular embolization ofthe cavernous sinus accessed via the inferior petrosal sinus, superiorophthalmic vein, or more rarely, the basilar plexus. A direct punctureof the superior ophthalmic vein or the cavernous sinus via pterionalcraniotomy is occasionally required for access. 颈内动脉海绵窦瘘也可引起第三、四、六组颅神经麻痹，可经过岩下窦， 眼上静脉或基底静脉丛用血管内介入治疗具有很好的疗效。偶尔也需要通过翼点开颅直接穿刺眼上静脉或海绵窦。
Indications for Microsurgery 显微手术的适应症
纵观自然病程，具有皮层静脉回流的硬脑膜动静脉瘘未经治疗，其发病率和死亡率均较高。硬脑膜动静脉瘘需闭塞瘘的静脉端；单纯的动脉端闭塞将导致治疗无效或无法达到根治的目的。 除非有难以忍受的耳鸣，视力减退或者疼痛等症状，无皮层静脉回流的病变一般无需治疗。对于此类型的硬脑膜动静脉瘘其治疗目标是缓解病情，而不是治愈。
不像动静脉畸形，其病变血管巢位于脑实质，且如果在所有供血动脉阻断之前静脉闭塞，则容易出血并破裂。硬脑膜动静脉瘘的病变则位于硬脑膜较局限而厚的区域。因此，静脉闭塞是安全且有效的。 有三种显微手术方法可以治疗硬脑膜动静脉瘘。第一种方法是直接栓塞或填充病变的硬脑膜静脉窦（对于颈内动脉海绵窦瘘行翼点开颅或海绵窦穿刺）。第二种方法手术切除硬脑膜动静脉瘘和相关的病变硬脑膜以及静脉窦。第三种方法，也是最常用的方法是单独断开动脉化的软脑膜回流静脉，而不是病灶的切除。 不能经动脉或静脉途径处理的一些硬脑膜动静脉瘘（还用是没有经静脉窦回流）则应用显微外科处理。像筛骨，前颅窝，岩上或小脑幕的硬脑膜动静脉瘘都可行显微手术治疗；由于它们与优势静脉窦无关，通常都具有皮层引流静脉。阻断动脉化的静脉来防止以后的出血。
MICROSURGICAL DISCONNECTION OF dAVFs 显微手术阻断硬脑膜动静脉瘘 显微手术结扎幕上及幕下的硬脑膜动静脉瘘在相应的章节详细介绍。
除非有脑内血肿引起的占位症状，对于硬脑膜动静脉瘘引起的急性脑出血，我不主张立即修复瘘管。如果不需要紧急清除血肿, 我主张在2-3天内择期手术切除瘘管。急诊干预，适用于破裂动脉瘤，而不适用于硬脑膜动静脉瘘。
Alternative Approaches 替代疗法
血管内介入治疗是现今治疗多数硬脑膜动静脉瘘的主要方式。经静脉栓塞是其主要途径，虽然在Onxy胶应用时代经动脉入路被常用，但如果导管能够定位到接近病灶，则Onxy胶可以被打到瘘的静脉端。
如果导管能够定位到被窦壁包裹的瘘管中，则经动脉栓塞可以保留窦腔；同时在使用液体栓塞材料栓塞时，使用静脉球囊保护静脉窦腔也能够保护窦腔。
立体定向放射治疗被用于不能行血管内介入治疗或外科手术治疗的瘘。也有一些应用伽马刀治愈的报道；然而，放射治疗对于高流量硬脑膜动静脉瘘的疗效有待于进一步研究。另外，放射治疗及其疗效使患者有每年15-20%脑出血的风险，
Microsurgical Resection of dAVFs 硬脑膜动静脉瘘的显微外科切除
硬脑膜动静脉瘘的显微外科切除包括供血动脉和皮层引流静脉的阻断以及病灶周围硬脑膜和闭塞/无功能硬脑膜静脉窦的切除。如果正常大脑静脉回流不受阻，则相关的硬脑膜静脉窦需要被切除。在此介绍术前经动脉栓塞供血动脉来减少术中失血量。尽管术前采取这些防止措施，但在开颅过程中做头皮切口和骨瓣时可能会大出血。
颅骨供血动脉丰富, 其需要足够数量的骨蜡来止血，因此颅骨切开术或切除术通常不得不行逐层钻孔。暴露受累的硬脑膜和相关静脉窦。接着受累的硬脑膜和供血动脉被烧灼，剪开并离断。切除相关的静脉窦，在静脉窦两侧平行于静脉窦周围剪开硬脑膜。最后，静脉窦病变处的近端和远端结扎，沿着病变硬脑膜将其切除。 所有动脉化的皮层回流静脉在静脉窦的人口将其切断。我通常应用术中血管造影来确定瘘的清除情况。若静脉窦有功能，且参与大脑的正常静脉回流，则因该将其分离并原位保留。
静脉窦的彻底暴露需要沿着窦的各面阻断硬脑膜病灶供血，然后完全中断供应瘘管的脑膜动脉。此方法可以保留静脉窦和未动脉化的皮层静脉。横窦、乙状窦或上矢状窦后部的硬脑膜动静脉瘘需要电凝并切断临近静脉窦的小脑幕和大脑镰。术中荧光造影可以区别动脉化的静脉和正常未动脉化的静脉。
Transverse/Sigmoid Sinus dAVF 横窦/乙状窦硬脑膜动静脉瘘
横窦/乙状窦的硬脑膜动静脉瘘是颅内最常见的硬脑膜动静脉瘘。其主要的供血动脉起自枕动脉的乳突支、耳后动脉和脑膜中动脉，还可能为咽升动脉。其静脉回流经过同侧的横窦或乙状窦，当同侧静脉窦闭塞时，其静脉回流可经过对侧。
血管内介入治疗可以有效处理这些病变。有时血管内介入治疗无效或因其血管通道受限而采取显微外科治疗。术前经动脉栓塞是减少术中大出血的关键。
我更喜欢公园椅位，头部转向地面,病变在头的最高点。术中根据CT血管造影图像，用马蹄形或“S”形切开暴露瘘管的部位。
过度增大的枕动脉和耳后动脉可以电凝或夹闭后切断。头皮和枕下肌为瘘提供大量血供，逐步彻底止血是至关重要的。
开颅暴露横窦和其上下的硬脑膜。我习惯于咬开骨窗而不是颅骨切开，这可以防止提起骨瓣时骨窦的急剧大出血。通过额外的钻孔可以避免硬脑膜的撕裂。通过明胶海绵或止血纱布填塞可以控制硬脑膜的大出血。硬脑膜的供血动脉可以通过双极电凝或止血夹进行控制。 硬膜内部分的操作是基于底部硬脑膜动静脉瘘的特殊解剖。如果要目标是动脉化的皮层回流静脉，则在基于横窦和这些回流静脉相应的部位切开硬脑膜。需要找到所有动脉化的静脉并切断。术中荧光造影可以确定目标。
如果手术目标是切除闭塞的静脉窦的瘘管，可用高速金刚磨钻行单侧乳突局部切除。此方法应暴露硬脑膜外侧及乙状窦前，平行于横窦/乙状窦的长轴在其上下方切入。逐步将供血动脉电凝或离断。游离的无功能的横窦/乙状窦，用两根缝合线通过小脑幕结扎静脉窦的两端。 通过腰大池释放脑脊液后，轻柔的抬高枕叶、牵拉小脑。此方法可以进一步暴露小脑幕并切断其所有血供血管，以便结扎部分静脉窦以及平行切开小脑幕。此技术可以游离硬脑膜静脉窦的病灶段。
找到所有动脉化的软膜静脉并分离。需要保护引流到横窦或乙状窦的未动脉化Labbe 静脉。若Labbe 静脉已被动脉化，则需被切断。
Other Considerations 注意事项
对于没有皮层静脉回流的患者，应给予观察。每3 - 5年复查血管造影动态评估畸形血管的结构，并排除新进展的皮层静脉回流的风险。
Pearls and Pitfalls 经验与教训
Contributors: Thomas Wilson, BS, and Stacey Quitero-Wolfe, MD DOI: https:///10.18791/nsatlas.v3.ch03.1 原著作者: Aaron Cohen 编译者：比拉力·巴拉江，新疆医科大学第一附属医院神经外科，在读研究生，导师:更·党木仁加甫。 审校：李远志，湖南省衡阳市中心医院，神经外科，医学硕士，副主任医师。 |
|
|
