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.

顱內(nèi)硬腦膜動(dòng)靜脈瘺是一種由動(dòng)脈和靜脈之間繞過(guò)毛細(xì)血管床而異常連接的獲得性病變。硬腦膜局部是由頸外動(dòng)脈的分支,頸內(nèi)動(dòng)脈的小腦幕支,椎動(dòng)脈的腦膜支和極少部分腦動(dòng)脈的軟膜支供血,。

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.

硬腦膜動(dòng)靜脈瘺（ dAVFs）,，確切地說(shuō)瘺管本身位于硬腦膜靜脈竇壁，其形成可能是由于硬腦膜靜脈竇的血栓,、感染,、前期的手術(shù)或外傷, 但多數(shù)情況下是自發(fā)性的。炎癥可以使瘺管周圍聚集高濃度的血管內(nèi)皮生長(zhǎng)因子,，最終導(dǎo)致血管再生,。這些瘺管的一部分可直接與大腦皮層（或軟膜）靜脈相通。

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發(fā)育理論,，其涉及動(dòng)靜脈的炎性反應(yīng)或靜脈竇閉塞引起的動(dòng)靜脈胚胎期原始連接的異常再通,。

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.

動(dòng)靜脈畸形在普通人群中的發(fā)病率約為0.15%，其中大約10% ～15%為dAVFs,。硬腦膜動(dòng)靜脈瘺具有多個(gè)分類系統(tǒng),，這些分類系統(tǒng)都是基于病變的引流靜脈模式而制定，從而決定了病變的表現(xiàn)形式,。1978年,，Djindjian和Merland根據(jù)靜脈血管架構(gòu)首次將dAVFs進(jìn)行分型。1995年,，Cognard根據(jù)dAVF的靜脈流向相關(guān)的預(yù)后因素及治療并發(fā)癥,，進(jìn)一步將顱內(nèi)和脊髓的dAVF進(jìn)行分類。

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 簡(jiǎn)化了Cognard分類,強(qiáng)調(diào)皮層引流靜脈是預(yù)測(cè)一個(gè)臨床診療結(jié)局的主要因素,。不同于靜脈竇,，皮層靜脈不受硬腦膜的保護(hù)，不能承受動(dòng)脈壓,。因此,，具有皮層靜脈返流(Borden分型 II和III型)的硬腦膜動(dòng)靜脈瘺可能有更高的破裂或出血的風(fēng)險(xiǎn)，其出血特點(diǎn)可能為腦實(shí)質(zhì)出血,，蛛網(wǎng)膜下腔出血或硬膜下出血,。

表1: 硬腦膜動(dòng)靜脈瘺分型

Intracranial hemorrhage and neurologic deficit is likely in 2% of theBorden classification type I, 39% of type II, and 79% of type III dAVFs.

硬腦膜動(dòng)靜脈瘺Borden分型I 型其腦出血和神經(jīng)功能缺陷約占2%,，II 型約39% ,，III 型約占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.

低級(jí)別的硬腦膜動(dòng)靜脈瘺(Borden I型)最常見的一個(gè)臨床表現(xiàn)是搏動(dòng)性耳鳴,聽診時(shí)可出現(xiàn)雜音,。其他癥狀包括頭痛或靜脈淤血導(dǎo)致的惡化性精神癥狀,。大的靜脈擴(kuò)張或靜脈竇壓力增加引起的腦脊液回流受阻都可導(dǎo)致腦積水或水腫。

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.

無(wú)皮層靜脈回流的硬腦膜動(dòng)靜脈瘺的自然史屬于良性病變,。硬腦膜動(dòng)靜脈瘺僅有 1% 會(huì)從Borden I型 和 II型轉(zhuǎn)變?yōu)锽orden III型,。然而，有皮層靜脈返流的硬腦膜動(dòng)靜脈瘺4年以上的死亡率為45%,，每年其腦出血率為19.2%,、神經(jīng)功能缺損為10.9%。出現(xiàn)腦出血的患者,，其初次出血后2周以內(nèi),，再出血率為35% 。靜脈狹窄是一個(gè)讓人擔(dān)憂的問(wèn)題,，其提示病變的惡化或靜脈通道的減少,。

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.

硬腦膜動(dòng)靜脈瘺手術(shù)方式的選擇與失血量相關(guān)聯(lián)，因此,血管內(nèi)介入治療適用于大部分的病變,，但是,，對(duì)于篩骨、巖骨或小腦幕區(qū)的硬腦膜動(dòng)靜脈瘺不適用,。硬腦膜動(dòng)靜脈瘺術(shù)中大出血的概率可能大于其他部位的動(dòng)靜脈瘺,。在討論手術(shù)技巧之前，我們將回顧顱內(nèi)硬腦膜動(dòng)靜脈瘺的幾種亞型,。

Classifications and Operative Considerations 分類及手術(shù)注意事項(xiàng)

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.

目前發(fā)現(xiàn)大多數(shù)（60%）顱內(nèi)硬腦膜動(dòng)靜脈瘺位于橫竇和乙狀竇的交匯處,，其次位于海綿竇和上矢狀竇。橫竇和乙狀竇的交匯處的硬腦膜動(dòng)靜脈瘺主要應(yīng)用血管內(nèi)介入治療,，這樣可以直接經(jīng)靜脈途徑閉塞瘺管或靜脈竇,。

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.

圖 1: 上圖展示了最常見的顱內(nèi)硬腦膜動(dòng)靜脈瘺幾種類型的位置和發(fā)病率。篩骨和巖骨處的動(dòng)靜脈瘺適合顯微外科結(jié)扎,，而其他類型的硬腦膜動(dòng)靜脈瘺更適合血管內(nèi)介入治療,。

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.

在具有側(cè)支回流靜脈的前提下，通過(guò)血管內(nèi)介入栓塞可以使靜脈竇閉塞,。例如,，在左側(cè)橫竇和乙狀竇的交匯處的硬腦膜動(dòng)靜脈瘺中，可以通過(guò)血管內(nèi)治療閉塞左側(cè)橫竇( 只要Labbé靜脈未受損),。同樣,，治療頸內(nèi)動(dòng)脈海綿竇瘺必須完全栓塞海綿竇,，其靜脈回流可經(jīng)蝶頂竇和側(cè)裂靜脈重新回流至上矢狀竇。 

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.

經(jīng)動(dòng)脈途徑栓塞可到達(dá)瘺的靜脈端,。但是必須同時(shí)栓塞靜脈端,，僅栓塞動(dòng)脈端可能會(huì)導(dǎo)致瘺的再通。

Diagnosis and Evaluation 診斷與評(píng)價(jià)

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.

在頸動(dòng)脈海綿竇瘺的患者中,，計(jì)算機(jī)斷層掃描(CT)或磁共振成像(MRI)能夠顯示過(guò)度充盈的回流靜脈或擴(kuò)張的眼上靜脈,。血管造影的特征性表現(xiàn)是在動(dòng)脈相上顱內(nèi)靜脈或靜脈竇早顯。

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)可能不會(huì)發(fā)現(xiàn)硬腦膜動(dòng)靜脈瘺,。三維磁共振血管造影可能有所幫助,但傳統(tǒng)的導(dǎo)管或數(shù)字減影血管造影術(shù)仍然是診斷與治療硬腦膜動(dòng)靜脈瘺的金標(biāo)準(zhǔn),。血管造影應(yīng)同時(shí)評(píng)估頸內(nèi)動(dòng)脈,頸外動(dòng)脈和椎動(dòng)脈。血管造影應(yīng)是全方位的,因?yàn)閮H頸內(nèi)動(dòng)脈或椎動(dòng)脈造影可能導(dǎo)致醫(yī)生漏診由頸外動(dòng)脈供血的硬腦膜動(dòng)靜脈瘺,。此外,即使是一個(gè)簡(jiǎn)單的硬腦膜動(dòng)靜脈瘺也可能具有來(lái)自不同供血?jiǎng)用}的多個(gè)滋養(yǎng)動(dòng)脈,。

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.

硬腦膜動(dòng)靜脈瘺的病灶處是動(dòng)靜脈分流的中心，也是硬腦膜上所有滋養(yǎng)動(dòng)脈匯集處,，同時(shí)是引流靜脈轉(zhuǎn)向的部位,。 盡管存在大量的引流靜脈和過(guò)度充盈擴(kuò)張的靜脈，但單個(gè)粗大的引流靜脈通常是瘺最主要的引流部位,。

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,，必須評(píng)估皮層引流靜脈的存在與否，靜脈竇閉塞,，硬腦膜靜脈竇的引流方向(順行或逆行) 以及正常的皮層周圍引流靜脈的解剖,。

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.

仔細(xì)觀察血管造影的靜脈相以確定正常的大腦中血液沒(méi)有引流入一個(gè)重要的靜脈(Labbe靜脈)，而是流入動(dòng)脈化的目標(biāo)靜脈中,。如果是這樣, 在分離動(dòng)脈化的靜脈的過(guò)程中應(yīng)該小心保留未動(dòng)脈化的靜脈,。

Supratentorial Dural Arteriovenous Fistulas  幕上的硬腦膜動(dòng)靜脈瘺

The majority of superatentrial fistulas that are amenable to operativeintervention are ethmoidal and parasagittal dAVFs.

大多數(shù)能夠手術(shù)干預(yù)的硬腦膜動(dòng)靜脈瘺是篩骨和矢狀竇旁區(qū)的硬腦膜動(dòng)靜脈瘺。

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.

圖 2: 左側(cè)頸外動(dòng)脈的正位片（左圖）和左側(cè)頸內(nèi)動(dòng)脈的側(cè)位片（右圖）展示了由篩前動(dòng)脈和鐮狀動(dòng)脈供血的引流入擴(kuò)張的動(dòng)脈化的皮層靜脈的篩骨區(qū)硬腦膜動(dòng)靜脈瘺,。

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.

篩骨的瘺管位于前顱窩底,，其供血?jiǎng)用}是篩前動(dòng)脈，眼動(dòng)脈的腦膜支以及沿眼動(dòng)脈上升的大腦鐮前動(dòng)脈,，也可能通過(guò)腦膜中動(dòng)脈的前支血供,，它們互相連接到瘺管，隱藏連接在額極或大腦鐮內(nèi)側(cè)的前顱窩底硬腦膜基底部軟膜靜脈 (嗅靜脈和額靜脈),。

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.

動(dòng)脈化的靜脈擴(kuò)張具有明顯的出血風(fēng)險(xiǎn),，在一些案例中其風(fēng)險(xiǎn)高達(dá)57%。由于這些靜脈具有軟膜的特征,，經(jīng)靜脈途徑血管內(nèi)介入不能到達(dá),。而經(jīng)動(dòng)脈通路是通過(guò)眼動(dòng)脈進(jìn)行,其經(jīng)動(dòng)脈栓塞可能導(dǎo)致失明。在“幕上硬腦膜動(dòng)靜脈瘺”章節(jié)中提到的外科治療則具有簡(jiǎn)單易行,、低風(fēng)險(xiǎn)等優(yōu)點(diǎn),。

Infratentorial Dural Arteriovenous Fistulas  幕下硬腦膜動(dòng)靜脈瘺

The majority of infratentorial dAVFs that are suitable to microsurgery are superior petrosal dAVFs.

多數(shù)適合顯微手術(shù)的幕下硬腦膜動(dòng)靜脈瘺是巖骨區(qū)的硬腦膜動(dòng)靜脈瘺,。

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.

圖 3: 頸內(nèi)動(dòng)脈側(cè)位造影片展示了小腦幕/巖骨的硬腦膜動(dòng)靜脈瘺，由頸內(nèi)動(dòng)脈的小腦幕支供血,，將后顱窩區(qū)的靜脈動(dòng)脈化流入巖靜脈,。

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

巖上的硬腦膜動(dòng)靜脈瘺通過(guò)血管內(nèi)介入很難到達(dá)其動(dòng)脈端或靜脈端。他們的供血?jiǎng)用}來(lái)自頸內(nèi)動(dòng)脈的小腦幕動(dòng)脈分支,，如天幕動(dòng)脈的下外側(cè)干和腦膜垂體干,；也有來(lái)自頸外動(dòng)脈的分支,，如腦膜中動(dòng)脈和咽升動(dòng)脈,。它們流入動(dòng)脈化的巖靜脈中，形成大的幕上或幕下動(dòng)脈化的擴(kuò)張靜脈,。這些病灶可以經(jīng)乙狀竇后入路通過(guò)夾閉動(dòng)脈化的巖上竇來(lái)治療,。此方法在“幕下硬腦膜動(dòng)靜脈瘺”這一章節(jié)中詳細(xì)介紹。

A large venous varix associated with the fistula can cause trigeminalneuralgia by compression of the root entry zone of the trigeminalnerve.

大的擴(kuò)張靜脈可通過(guò)壓迫三叉神經(jīng)根入口區(qū)引起三叉神經(jīng)痛,。

Cavernous-Carotid Fistulas 頸內(nèi)動(dòng)脈海綿竇瘺

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.

頸內(nèi)動(dòng)脈海綿竇瘺是顱內(nèi)硬腦膜動(dòng)靜脈瘺的一個(gè)特殊類型,，它是頸內(nèi)動(dòng)脈和海綿竇的相溝通。此類型可能是頸內(nèi)動(dòng)脈直接與海綿竇溝通,，屬于高流量瘺,，常見于外傷；或者是頸內(nèi)動(dòng)脈或頸外動(dòng)脈的分支動(dòng)脈間接溝通引起,。

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.

頸內(nèi)動(dòng)脈海綿竇瘺雖然可以表現(xiàn)為皮層靜脈逆行引流癥狀,，但眼部癥狀是其特有癥狀。初期癥狀包括突眼,球結(jié)膜水腫與眼內(nèi)壓的升高,。青光眼 (IOP > 20)可致失明, 需要盡快治療,。

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.

頸內(nèi)動(dòng)脈海綿竇瘺也可引起第三、四,、六組顱神經(jīng)麻痹,，可經(jīng)過(guò)巖下竇， 眼上靜脈或基底靜脈叢用血管內(nèi)介入治療具有很好的療效,。偶爾也需要通過(guò)翼點(diǎn)開顱直接穿刺眼上靜脈或海綿竇,。

Indications for Microsurgery  顯微手術(shù)的適應(yīng)癥

縱觀自然病程，具有皮層靜脈回流的硬腦膜動(dòng)靜脈瘺未經(jīng)治療,，其發(fā)病率和死亡率均較高,。硬腦膜動(dòng)靜脈瘺需閉塞瘺的靜脈端；單純的動(dòng)脈端閉塞將導(dǎo)致治療無(wú)效或無(wú)法達(dá)到根治的目的,。

除非有難以忍受的耳鳴,，視力減退或者疼痛等癥狀，無(wú)皮層靜脈回流的病變一般無(wú)需治療,。對(duì)于此類型的硬腦膜動(dòng)靜脈瘺其治療目標(biāo)是緩解病情,，而不是治愈,。

不像動(dòng)靜脈畸形，其病變血管巢位于腦實(shí)質(zhì),，且如果在所有供血?jiǎng)用}阻斷之前靜脈閉塞,，則容易出血并破裂。硬腦膜動(dòng)靜脈瘺的病變則位于硬腦膜較局限而厚的區(qū)域,。因此,，靜脈閉塞是安全且有效的。

有三種顯微手術(shù)方法可以治療硬腦膜動(dòng)靜脈瘺,。第一種方法是直接栓塞或填充病變的硬腦膜靜脈竇（對(duì)于頸內(nèi)動(dòng)脈海綿竇瘺行翼點(diǎn)開顱或海綿竇穿刺）,。第二種方法手術(shù)切除硬腦膜動(dòng)靜脈瘺和相關(guān)的病變硬腦膜以及靜脈竇。第三種方法,，也是最常用的方法是單獨(dú)斷開動(dòng)脈化的軟腦膜回流靜脈,，而不是病灶的切除。

不能經(jīng)動(dòng)脈或靜脈途徑處理的一些硬腦膜動(dòng)靜脈瘺（還用是沒(méi)有經(jīng)靜脈竇回流）則應(yīng)用顯微外科處理,。像篩骨,，前顱窩，巖上或小腦幕的硬腦膜動(dòng)靜脈瘺都可行顯微手術(shù)治療,；由于它們與優(yōu)勢(shì)靜脈竇無(wú)關(guān),，通常都具有皮層引流靜脈。阻斷動(dòng)脈化的靜脈來(lái)防止以后的出血,。

MICROSURGICAL DISCONNECTION OF dAVFs  顯微手術(shù)阻斷硬腦膜動(dòng)靜脈瘺

顯微手術(shù)結(jié)扎幕上及幕下的硬腦膜動(dòng)靜脈瘺在相應(yīng)的章節(jié)詳細(xì)介紹,。

除非有腦內(nèi)血腫引起的占位癥狀，對(duì)于硬腦膜動(dòng)靜脈瘺引起的急性腦出血,，我不主張立即修復(fù)瘺管,。如果不需要緊急清除血腫, 我主張?jiān)?-3天內(nèi)擇期手術(shù)切除瘺管。急診干預(yù),，適用于破裂動(dòng)脈瘤,，而不適用于硬腦膜動(dòng)靜脈瘺。

Alternative Approaches 替代療法

血管內(nèi)介入治療是現(xiàn)今治療多數(shù)硬腦膜動(dòng)靜脈瘺的主要方式,。經(jīng)靜脈栓塞是其主要途徑,，雖然在Onxy膠應(yīng)用時(shí)代經(jīng)動(dòng)脈入路被常用，但如果導(dǎo)管能夠定位到接近病灶,，則Onxy膠可以被打到瘺的靜脈端,。

如果導(dǎo)管能夠定位到被竇壁包裹的瘺管中，則經(jīng)動(dòng)脈栓塞可以保留竇腔,；同時(shí)在使用液體栓塞材料栓塞時(shí),，使用靜脈球囊保護(hù)靜脈竇腔也能夠保護(hù)竇腔。

立體定向放射治療被用于不能行血管內(nèi)介入治療或外科手術(shù)治療的瘺,。也有一些應(yīng)用伽馬刀治愈的報(bào)道,；然而,，放射治療對(duì)于高流量硬腦膜動(dòng)靜脈瘺的療效有待于進(jìn)一步研究。另外,，放射治療及其療效使患者有每年15-20%腦出血的風(fēng)險(xiǎn),，

Microsurgical Resection of dAVFs  硬腦膜動(dòng)靜脈瘺的顯微外科切除

硬腦膜動(dòng)靜脈瘺的顯微外科切除包括供血?jiǎng)用}和皮層引流靜脈的阻斷以及病灶周圍硬腦膜和閉塞/無(wú)功能硬腦膜靜脈竇的切除。如果正常大腦靜脈回流不受阻,，則相關(guān)的硬腦膜靜脈竇需要被切除,。在此介紹術(shù)前經(jīng)動(dòng)脈栓塞供血?jiǎng)用}來(lái)減少術(shù)中失血量。盡管術(shù)前采取這些防止措施,，但在開顱過(guò)程中做頭皮切口和骨瓣時(shí)可能會(huì)大出血,。

顱骨供血?jiǎng)用}豐富, 其需要足夠數(shù)量的骨蠟來(lái)止血，因此顱骨切開術(shù)或切除術(shù)通常不得不行逐層鉆孔,。暴露受累的硬腦膜和相關(guān)靜脈竇,。接著受累的硬腦膜和供血?jiǎng)用}被燒灼,，剪開并離斷,。切除相關(guān)的靜脈竇，在靜脈竇兩側(cè)平行于靜脈竇周圍剪開硬腦膜,。最后,，靜脈竇病變處的近端和遠(yuǎn)端結(jié)扎，沿著病變硬腦膜將其切除,。

所有動(dòng)脈化的皮層回流靜脈在靜脈竇的人口將其切斷,。我通常應(yīng)用術(shù)中血管造影來(lái)確定瘺的清除情況。若靜脈竇有功能,，且參與大腦的正常靜脈回流,，則因該將其分離并原位保留。

靜脈竇的徹底暴露需要沿著竇的各面阻斷硬腦膜病灶供血,，然后完全中斷供應(yīng)瘺管的腦膜動(dòng)脈,。此方法可以保留靜脈竇和未動(dòng)脈化的皮層靜脈。橫竇,、乙狀竇或上矢狀竇后部的硬腦膜動(dòng)靜脈瘺需要電凝并切斷臨近靜脈竇的小腦幕和大腦鐮,。術(shù)中熒光造影可以區(qū)別動(dòng)脈化的靜脈和正常未動(dòng)脈化的靜脈。

Transverse/Sigmoid Sinus dAVF 橫竇/乙狀竇硬腦膜動(dòng)靜脈瘺

橫竇/乙狀竇的硬腦膜動(dòng)靜脈瘺是顱內(nèi)最常見的硬腦膜動(dòng)靜脈瘺,。其主要的供血?jiǎng)用}起自枕動(dòng)脈的乳突支,、耳后動(dòng)脈和腦膜中動(dòng)脈，還可能為咽升動(dòng)脈,。其靜脈回流經(jīng)過(guò)同側(cè)的橫竇或乙狀竇,，當(dāng)同側(cè)靜脈竇閉塞時(shí)，其靜脈回流可經(jīng)過(guò)對(duì)側(cè),。

血管內(nèi)介入治療可以有效處理這些病變,。有時(shí)血管內(nèi)介入治療無(wú)效或因其血管通道受限而采取顯微外科治療,。術(shù)前經(jīng)動(dòng)脈栓塞是減少術(shù)中大出血的關(guān)鍵。

我更喜歡公園椅位,，頭部轉(zhuǎn)向地面,病變?cè)陬^的最高點(diǎn),。術(shù)中根據(jù)CT血管造影圖像，用馬蹄形或“S”形切開暴露瘺管的部位,。 

過(guò)度增大的枕動(dòng)脈和耳后動(dòng)脈可以電凝或夾閉后切斷,。頭皮和枕下肌為瘺提供大量血供，逐步徹底止血是至關(guān)重要的,。

開顱暴露橫竇和其上下的硬腦膜,。我習(xí)慣于咬開骨窗而不是顱骨切開，這可以防止提起骨瓣時(shí)骨竇的急劇大出血,。通過(guò)額外的鉆孔可以避免硬腦膜的撕裂,。通過(guò)明膠海綿或止血紗布填塞可以控制硬腦膜的大出血。硬腦膜的供血?jiǎng)用}可以通過(guò)雙極電凝或止血夾進(jìn)行控制,。

硬膜內(nèi)部分的操作是基于底部硬腦膜動(dòng)靜脈瘺的特殊解剖,。如果要目標(biāo)是動(dòng)脈化的皮層回流靜脈，則在基于橫竇和這些回流靜脈相應(yīng)的部位切開硬腦膜,。需要找到所有動(dòng)脈化的靜脈并切斷,。術(shù)中熒光造影可以確定目標(biāo)。

如果手術(shù)目標(biāo)是切除閉塞的靜脈竇的瘺管,，可用高速金剛磨鉆行單側(cè)乳突局部切除,。此方法應(yīng)暴露硬腦膜外側(cè)及乙狀竇前，平行于橫竇/乙狀竇的長(zhǎng)軸在其上下方切入,。逐步將供血?jiǎng)用}電凝或離斷,。游離的無(wú)功能的橫竇/乙狀竇，用兩根縫合線通過(guò)小腦幕結(jié)扎靜脈竇的兩端,。

通過(guò)腰大池釋放腦脊液后,，輕柔的抬高枕葉、牽拉小腦,。此方法可以進(jìn)一步暴露小腦幕并切斷其所有血供血管,，以便結(jié)扎部分靜脈竇以及平行切開小腦幕。此技術(shù)可以游離硬腦膜靜脈竇的病灶段,。

找到所有動(dòng)脈化的軟膜靜脈并分離,。需要保護(hù)引流到橫竇或乙狀竇的未動(dòng)脈化Labbe 靜脈。若Labbe 靜脈已被動(dòng)脈化,，則需被切斷,。

Other Considerations 注意事項(xiàng)

對(duì)于沒(méi)有皮層靜脈回流的患者，應(yīng)給予觀察。每3 - 5年復(fù)查血管造影動(dòng)態(tài)評(píng)估畸形血管的結(jié)構(gòu),，并排除新進(jìn)展的皮層靜脈回流的風(fēng)險(xiǎn),。

Pearls and Pitfalls 經(jīng)驗(yàn)與教訓(xùn)

• 硬腦膜動(dòng)靜脈瘺的治愈必須栓塞瘺的靜脈端。

• 血管內(nèi)介入治療是多數(shù)包括頸內(nèi)動(dòng)脈海綿竇瘺,、橫竇和乙狀竇附近的動(dòng)靜脈瘺以及上矢狀竇的硬腦膜動(dòng)靜脈瘺在內(nèi)的硬腦膜動(dòng)靜脈瘺的一線治療方法,，因手術(shù)治療關(guān)系到術(shù)中大出血。

• 然而,，篩骨和巖骨的硬腦膜動(dòng)靜脈瘺仍需顯微手術(shù)干預(yù),，因其風(fēng)險(xiǎn)較小，且血管內(nèi)介入到達(dá)病灶極具挑戰(zhàn)性 ,。

Contributors: Thomas Wilson, BS, and Stacey Quitero-Wolfe, MD

DOI: https:///10.18791/nsatlas.v3.ch03.1