Adjuvant use of e-aminocaproic acid (Amicar) in the endovascular treatment of cranial arteriovenous fistulae

We report our experience with the use of the antifibrinolytic agent ɛ -aminocaproic acid (EACA), Amicar, as an adjuvant to endovascular treatment of cranial arteriovenous fistulae. We also review applications of antifibrinolytic agents to neurovascular disorders and discuss the mechanism of action, dosing strategy, contraindications, and possible complications associated with the use of EACA. We identified 13 patients with cranial arteriovenous fistulae (five direct carotid cavernous fistulae [CCF], seven dural arteriovenous fistulae [DAVF], and one vein of Galen malformation) who received EACA as an adjunct to endovascular treatment. In all cases embolic coils were the primary embolic agent. We reviewed the modes of initial endovascular therapy and angiographic findings immediately thereafter and the response to EACA. Two direct CCF and two DAVF were completely thrombosed on follow-up angiography, and two DAVF demonstrated diminished flow after EACA therapy. Seven fistulae did not respond to EACA. Four of eight tightly coiled fistulae thrombosed, while none of five loosely coiled fistulae thrombosed. None of four cases with a residual fistula separate from the coil mass underwent thrombosis with EACA, while four of nine cases without a separate fistula thrombosed. There was no morbidity related to EACA therapy. EACA may thus be useful as an adjunct to endovascular treatment of cranial arteriovenous fistulae. Loose or incomplete coil packing of the fistula predicts a poor response to EACA therapy. Received: 18 March 1999 Accepted: 11 August 1999     

Computed tomographic and digital subtraction angiography evaluation of ophthalmic-ethmoidal artery dural arteriovenous fistula

Ophthalmic-ethmoidal dural arteriovenous fistula (DAVFs) is a rare type of dural arteriovenous fistulas and usually presenting with spontaneous subarachnoid hemorrhage, subdural hemorrhage or ocular symptoms. We present a case of a 59-year old gentleman presenting with acute headache, vomiting and generalized weakness. CT study of the brain revealed a large left frontal hematoma and abnormal aneurysmal sac with dilated cortical vein, communicating with the superior sagittal sinus. Conventional angiography confirmed diagnosis of ruptured ophthalmic-ethmoidal DAVF, resulting in a frontal intra-axial hemorrhage. Anterior fossa DAVFs are extremely rare, difficult to diagnose and treat. CT angiography is initial method of diagnosis, but digital substruction angiography remains the gold standard of confirming dural fistulas.     

Recurrence of the cavernous sinus dural arteriovenous fistula at adjacent sinuses following repeated transvenous embolizations: case report and literature review

We present a unique case of a cavernous sinus (CS) dural arteriovenous fistula (DAVF), which recurred at adjacent sinuses following repeated transvenous embolizations (TVEs). A 68-year-old woman presented with progressive left conjunctival chemosis and diplopia. Cerebral angiography revealed a left CS DAVF, which was completely obliterated by TVE via the left inferior petrosal sinus (IPS). Two years later, the DAVF recurred in the left IPS, and again in the left sigmoid sinus (SS) 3 years after the initial treatment in spite of a second TVE. Moreover, the left SS and the left internal jugular vein, which had been previously stenotic, had been occluded. The third TVE resulted in the complete obliteration of the SS DAVF. CS DAVFs may recur at adjacent sinuses even after complete obliteration by TVE. Careful follow-up is necessary to check for the recurrence of DAVFs, especially in cases with venous flow changes, such as sinus occlusion, following endovascular treatment.     

硬脑膜动静脉瘘的治疗

目的　探讨不同方法治疗不同类型的硬脑膜动静脉瘘 (DAVF)的疗效。方法　采用经动脉入路在供血动脉内采用低浓度NBCA胶、弹簧圈、游离纤毛钢圈、PVA等栓塞治疗 ;经静脉入路在瘘口静脉端用弹簧圈栓塞 ,或直接开颅手术夹闭瘘口、静脉窦表面颅骨钻孔后直接穿刺作静脉窦内栓塞及静脉内支架植入等方法治疗不同部位和不同类型的DAVF 32例。结果　 8例前颅凹底DAVF ,5例经动脉入路栓塞治疗 ,2例治愈 ,3例临床好转 ;3例 (1例经静脉入路治疗失败后 )前颅凹底入路行开颅瘘口直接夹闭治愈。 14例海绵窦区DAVF ,7例经眼上静脉入路海绵窦内栓塞治愈 ,4例经动脉入路 ,治愈 1例 ,好转 3例。 5例横窦区DAVF ,2例经静脉入路窦内栓塞治愈 ,2例动脉入路栓塞后好转 ,1例行窦孤立手术治愈。 4例多处瘘口的上矢状窦DAVF ,联合多种治疗方法经多次治疗 ,临床好转。 1例左侧颈静脉孔区DAVF联合多种治疗方法经多次治疗治愈。结论　前颅凹底DAVF以直接手术行瘘口夹闭疗效好 ,经动脉入路低浓度胶栓塞可治愈但需注意危险吻合 ;海绵窦区DAVF经静脉入路栓塞多可治愈。横窦区DAVF静脉入路栓塞瘘口静脉端效果好 ;复杂性DAVF治疗困难 ,目前联合多种治疗方法可以达到临床改善。将治疗策略定在针对瘘口的静脉端 ,可望达到临床治愈。     

Dural arteriovenous fistula of the cervical spine presenting with subarachnoid hemorrhage

We describe a case of dural arteriovenous fistula (DAVF) presenting with subarachnoid hemorrhage (SAH). The diagnosis of DAVF was based on spinal angiography. A review of the literature revealed that five of 13 previously reported DAVFs of the cervical spine were accompanied by SAH. SAH has not been observed in DAVFs involving other segments of the spinal canal.     

Intracranial dural arteriovenous fistulas: evaluation with combined 3D time-of-flight MR angiography and MR digital subtraction angiography

OBJECTIVE: The purpose of this study was to compare the diagnostic utility of 3D time-of-flight (TOF) MR angiography and MR digital subtraction angiography in patients with angiographically proven moderate- to high-flow intracranial dural arteriovenous fistula. MATERIALS AND METHODS: Two neuroradiologists, unaware of patients' histories and angiographic findings, retrospectively reviewed 17 MR angiograms with 3D TOF MR angiography and MR digital subtraction angiography in 15 patients with dural arteriovenous fistula and also reviewed 35 MR angiograms in control patients without findings of dural arteriovenous fistula on angiography. Disagreements were resolved by consensus. RESULTS: In patients with dural arteriovenous fistula, source images of 3D TOF MR angiography showed two abnormal findings: multiple high-intensity curvilinear or nodular structures adjacent to the sinus wall and high-intensity areas in the venous sinus. Findings of multiple high-intensity structures adjacent to the sinus wall were observed in all cases of dural arteriovenous fistula. Findings of high-intensity areas in the venous sinus were observed in 13 of 17 cases of dural arteriovenous fistula. Findings of multiple high-intensity structures adjacent to the sinus wall were not observed in any control subjects. Findings of high-intensity areas within the venous sinus were observed in five of 35 control subjects. Findings of MR digital subtraction angiography showed early filling of the venous sinus, suggestive of dural arteriovenous fistula, in 13 of 15 patients with dural arteriovenous fistula. Sensitivity and specificity of multiple high-intensity structures adjacent to the sinus wall, high-intensity areas in the venous sinus, and early filling of the venous sinus were 100% and 100%, 76% and 86%, and 87% and 100%, respectively. Although 3D TOF MR angiography failed to show the findings of retrograde cortical venous drainage and venous sinus occlusion, MR digital subtraction angiography clearly showed both findings in all five subjects. CONCLUSION: A protocol including both 3D TOF MR angiography (source images) and MR digital subtraction angiography allowed the diagnosis of moderate- to high-flow dural arteriovenous fistula. In addition, cortical venous drainage was reliably noted in a small subset of patients.     

头颈部双源CT血管成像诊断硬脑膜动静脉瘘的价值探讨

目的探讨头颈部双源cT血管成像（CTA）诊断硬脑膜动静脉瘘（DAVF）的价值。方法收集2009年6月至2012年6月8例DAVF患者的头颈部CTA资料,以8例性别及年龄相似的正常头颈部CTA为对照组,对比分析DAVF患者与正常头颈部CTA的征象差异,分析征象包括畸形血管的供血动脉数量,患侧硬膜窦边缘是否规整,有无异常穿颅血管通道,大脑皮层静脉是否扩张以及双侧颈内静脉密度是否对称等。结果多支（≥3条）供血动脉诊断DAVF的特异性、敏感性分别为88％、100％。患侧静脉窦边缘不规则的敏感性较低（50％）,特异性很高（100％）。出现异常穿颅血管通道的敏感性较低（38％）,特异性较高（88％）。DAVF组的双侧颈内静脉密度不对称性差异存在统计学意义（P=0．017）。结论头颈部双源CTA对诊断DAVF具有较高的价值,出现多支供血动脉、患侧静脉窦边缘不规则及双侧颈内静脉密度不对称高度提示DAVF。     

Alteration in the venous drainage of a dural arteriovenous fistula following angioplasty

The pattern of venous drainage from a dural arteriovenous fistula (DAVF) has been shown to affect the natural history of these lesions. Angioplasty and stent placement of the dural sinuses have been described to improve outflow in venous hypertensive states and may improve the venous drainage pattern from a DAVF. We report the case of a patient with a benign but stenosed type IIa transverse sinus DAVF who underwent angioplasty to improve venous outflow. This resulted in conversion of the DAVF to a more malignant type IIb drainage pattern with reflux into the cortical venous system.     

Isolated cortical venous thrombosis and ulcerative colitis.

Aseptic cortical venous thrombosis is rare without concomitant dural sinus thrombosis. Ulcerative colitis is associated with both dural sinus thrombosis and isolated cortical venous thrombosis. We describe a 26-year-old woman with ulcerative colitis who had a spontaneous cerebral hemorrhage. An overlying thrombosed cortical vein was identified on spin-echo MR images and confirmed with angiography. Signal characteristics of thrombosed cortical veins are similar to those described in dural sinus thrombosis.     

Treatment of dural sinus thrombosis by urokinase infusion.

PURPOSETo gain a preliminary understanding of the role of thrombolytic therapy for the thrombosed dural sinus, we retrospectively reviewed our initial experience.METHODSSeven patients, ages 25 to 71, who presented with symptomatic dural sinus thrombosis and who failed a trial of medical therapy were treated with direct infusion of urokinase into the thrombosed sinus. Patients received urokinase doses ranging from 20,000 to 150,000 U/h with a mean infusion time of 163 hours (range 88 to 244 hours).RESULTSPatency of the affected dural sinus was achieved with antegrade flow in all patients. Six patients either improved neurologically over their prethrombolysis state or were healthy after thrombolysis; one of them required angioplasty. The other patient improved after surgical repair of a residual dural arteriovenous fistula. The only complications were an infected femoral access site which resolved after treatment with antibiotics and hematuria which cleared after discontinuation of anticoagulation.CONCLUSIONSThrombolysis of the thrombosed dural sinus shows promise as a safe and efficacious treatment. The results of this study should provide the impetus for further research.     

Phase-contrast MR angiography of intracranial dural arteriovenous fistulae

MRI and phase-contrast MR angiography (PC MRA) were obtained in 13 patients with angiographically confirmed intracranial dural arteriovenous fistulae (DAVF). Three- and two-dimensional PC MRA was obtained with low (6–20 cm/s) and high (> 40 cm/s) velocity encoding along the three main body axes. MRI showed focal or diffuse signal abnormalities in the brain parenchyma in six patients, dilated cortical veins in seven, venous pouches in four with type IV DAVF and enlargement of the superior ophthalmic vein in three patients with DAVF of the cavernous sinus. However, it showed none of the fistula sites and did not allow reliable identification of feeding arteries. 3D PC MRA enabled identification of the fistula and enlarged feeding arteries in six cases each. Stenosis or occlusion of the dural sinuses was detected in six of eight cases on 3D PC MRA with low velocity encoding. In six patients with type II DAVF phase reconstruction of 2D PC MRA demonstrated flow reversal in the dural sinuses or superior ophthalmic vein. Received: 14 May 1998 Accepted: 15 December 1998     

Recurrence of dural arteriovenous fistula in another location after selective transvenous coil embolization: report of two cases

Two cases of a second dural arteriovenous fistula (DAVF), both developing in different locations after selective transvenous embolization of the first DAVF, are presented. One recurrent DAVF developed on the sigmoid sinus 5 months after transvenous embolization of a DAVF in the paratransverse sinus channel, and the other recurrence developed around the jugular bulb 5 months after transvenous embolization of a cavernous DAVF. The former was obliterated by a second embolization, and the latter disappeared spontaneously at 20 months.     

硬脑膜动静脉瘘的治疗

目的 探讨不同方法治疗的不同类型的硬脑膜动静脉瘘(DAVF)的疗效。方法 采用经动脉入路在供血动脉内采用低浓度NBCA胶、弹簧圈、游离纤毛钢圈、PVA等栓塞治疗；经静脉入路在瘘口静脉端用弹簧圈栓塞，或直接开颅手术夹闭瘘口、静脉窦表面颅骨钻孔后直接穿刺作静脉窦内栓塞及静脉内支架植入等方法治疗不同部位和不同类型的DAVF32例。结果 8例前颅凹底DAVF，5例经动脉入路栓塞治疗，2例治愈，3例临床好转；3例(1例经静脉入路治疗失败后)前颅凹底入路行开颅瘘口直接夹闭治愈。14例海绵窦区DAVF，7例经眼上静脉入路海绵窦内栓塞治愈，4例经动脉入路，治愈1例，好转3例。5例横窦区DAVF，2例经静脉入路窦内栓塞治愈，2例动脉入路栓塞后好转，1例行窦孤立手术治愈。4例多处瘘口的上矢状窦DAVF，联合多种治疗方法经多次治疗，临床好转。1例左侧颈静脉孔区DAVF联合多种治疗方法经多次治疗治愈。结论 前颅凹底DAVF以直接手术行瘘口夹闭疗效好，经动脉入路低浓度胶栓塞可治愈但需注意危险吻合；海绵窦区DAVF经静脉入路栓塞多可治愈。横窦区DAVF静脉入路栓塞瘘口静脉端效果好；复杂性DAVF治疗困难，目前联合多种治疗方法可以达到临床改善。将治疗策略定在针对瘘口的静脉端，可望达到临床治愈。     

Suspected dural arteriovenous fistula: results with screening MR angiography in seven patients.

Previous studies have shown that spin-echo (SE) magnetic resonance (MR) imaging has been helpful in the assessment of dural arteriovenous fistula (DAVF); however, direct visualization of the fistula site is limited. Thus, conventional plain angiography is required to establish the diagnosis. Because of this limitation, the additional use of MR angiography may improve noninvasive screening for this disorder. Seven patients with DAVFs proved at plain angiography were evaluated with SE MR imaging and with three-dimensional (3D) time-of-flight (TOF) MR angiography. In six of seven cases, 3D TOF MR angiography demonstrated the fistula site. Correlation was good when compared with findings at plain angiography. Occlusion of the dural sinus was found at plain angiography in three of seven patients but was missed at SE imaging in all three. MR angiography also failed to demonstrate sinus occlusion in two of three patients. Arterial feeders could not be seen on SE MR images, but MR angiography improved their depiction. Plain angiography demonstrated abnormal venous drainage into distended cortical veins in three patients, but dilated cortical veins were noted in only two of the patients on both SE MR images and MR angiograms.     

Thrombosis of aggressive dural arteriovenous fistula after incomplete embolization

We report the cases of three patients diagnosed with dural arteriovenous fistula (DAVF) and cortical venous reflux (CVR). All were treated by transarterial endovascular embolization. Residual shunting and cortical venous drainage continued to be present at the end of the treatment procedure, despite the fact that during endovascular embolization glue penetration into the proximal venous component of the fistula had been achieved. Subsequently, follow-up angiography showed total obliteration of the fistulas and absent associated CVR. The fistulas were no longer opacified, and no additional treatment was performed. We demonstrate that residual aggressive DAVF may progress to total thrombosis if strategic deposition of the glue into the venous side has been achieved. Early follow-up angiogram is recommended prior to a planned complementary surgical approach.     

Follow-up MRI in dural arteriovenous malformations involving the cavernous sinus: emphasis on detection of venous thrombosis

Summary Six patients with a dural arteriovenous malformation (dural AVM) involving the cavernous sinus were followed up with magnetic resonance imaging in order to assess change in the lesions. Spin-echo (SE) imaging of three patients in whom the AVM appeared to have closed at least 1 month earlier (two of them spontaneously, and one after external carotid artery embolization) showed neither apparent flow void in the involved cavernous sinus nor evidence of venous thrombosis. SE images of the other three patients who had not been cured by external carotid artery embolization (two of whom were examined within a week of treatment), detected persisting arteriovenous shunts, including high-flow cortical venous drainage, seen as flow void. Two-dimensional time-of-flight MR angiography (2D TOF MRA) was performed simultaneously in three patients. Whereas shunting blood and the normal cavernous sinus were of high intensity, presumed thrombosed cavernous sinuses were isointense with stationary brain tissue. SE imaging can confirm the resolution of arteriovenous shunts, but poorly delineates ver acute and chronic thrombosis of the draining veins. In contrast, 2D TOF MRA directly demonstrates flowing blood, permitting the diagnosis of venous thrombosis; it should be included in follow-up of a dural AVM involving the cavernous sinus when venous thrombosis is suspected.     

Dural arteriovenous fistula involving the transverse sigmoid sinus after treatment: assessment with magnetic resonance digital subtraction angiography

Introduction The purpose of this study was to evaluate the utility of magnetic resonance digital subtraction angiography (MRDSA) in showing the presence or absence of retrograde venous drainage (RVD) in patients with intracranial dural arteriovenous fistula (DAVF) involving the transverse sigmoid sinus (TSS) after treatment. Methods Of 16 patients with DAVF involving the TSS, 13 underwent digital subtraction angiography (DSA) and MRDSA before and after treatment, and 3 underwent DSA before treatment and DSA and MRDSA after treatment. Five patients underwent these procedures twice after treatment. A total of 21 examinations after treatment were evaluated retrospectively. The presence or absence of DAVF and RVD was decided on the basis of the DSA findings. Two neuroradiologists reviewed the MRDSA findings concerning the presence or absence of DAVF and RVD. Results DSA showed residual DAVF in 9 and residual RVD in 5 of 21 examinations. MRDSA revealed residual DAVF in 8 of 21 examinations. MRDSA did not show residual DAVF in one examination because of a very small (low-flow) residual DAVF without RVD. MRDSA identified residual RVD in 5 of 21 examinations. MRDSA was completely consistent with DSA concerning the presence or absence of residual RVD. Conclusion MRDSA could evaluate the presence or absence of RVD in patients with DAVF involving TSS after treatment. MRDSA may give reliable information as to whether patients with DAVF involving the TSS should undergo additional DSA after treatment.     

Magnification angiography of dural carotid-cavernous sinus fistulae

Summary Eleven patients with dural carotid-cavernous sinus fistulae were studied with selective magnification angiography. The angiographic features of this condition were analyzed in detail. The arterial plexus normally present in and around the cavernous sinus has been thought to rupture into the sinus and establish an arteriovenous fistula with an extensive dural arterial supply. Changeable angiographic and clinical findings, including spontaneous regression, can be explained on the basis of thrombosis and occlusion in the arterial network. The indications for and methods of embolization are also discussed.     

Dural arteriovenous fistulas involving the inferior petrosal sinus: angiographic findings in six patients

We report the angiographic findings from six patients with intracranial dural arteriovenous fistulas of the inferior petrosal sinus and describe the clinical presentation, vascular anatomy, and embolization techniques used in the treatment of this disorder. Dural arteriovenous fistulas at this site are rare; of 105 patients diagnosed with this abnormality, only six had lesions involving the inferior petrosal sinus. The patients included three men and three women, ranging in age from 41 to 75 years. Patients presented with bruit, proptosis, abducens palsy, or loss of vision, and symptoms were present for up to 1 year prior to diagnosis. These presentations were similar to cavernous sinus arteriovenous fistulas. The arterial supply in all cases was from branches of the external carotid artery and in three cases from the meningohypophyseal trunk of the internal carotid artery. Venous drainage in four patients was via the cavernous sinus to the superior ophthalmic vein. The remaining two patients had drainage primarily to the jugular bulb. In four patients treatment was performed by introducing wire coils into the fistula from the transvenous route. This approach could be used even though the inferior petrosal sinus was thrombosed. One patient, treated early in the series, had only transarterial embolization with both liquid adhesives and particulate embolic agents. One patient had an asymptomatic fistula that was not treated. All patients were cured, as evidenced both angiographically and clinically during the follow-up period. Three patients experienced complications from angiography and treatment: two had transverse sinus thrombosis and one had a transient ischemic attack.     

Arterialization of cerebral veins on dynamic MDCT angiography: a possible sign of a dural arteriovenous fistula

OBJECTIVE: MDCT angiography allows fast imaging of the cerebral vessels, and its potential as a noninvasive technique to detect vascular abnormalities on the basis of morphologic changes is well established. We analyzed vascular enhancement patterns of cerebral venous structures on MDCT angiography, which enabled us to diagnose dural arteriovenous fistula. CONCLUSION: MDCT angiography performed during an early arterial phase showed asymmetrically higher contrast intensity in the transverse or sigmoid sinus, or both, in five patients. In all patients, digital subtraction angiography confirmed the presence of a dural arteriovenous fistula on the side on which the higher contrast intensity appeared. Radiologists should actively look for this sign in the imaging workup of patients presenting with nonspecific symptoms that might be related to a dural arteriovenous fistula.