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.     

椎管内血管畸形的血管造影诊断与血管内介入治疗

目的:探讨椎管内血管畸形的血管造影诊断与血管内介入治疗效果。方法:回顾性分析66例椎管内血管畸形的选择性动脉造影与栓塞治疗资料。结果:66例椎管内血管畸形的血管造影表现为隐匿性髓内血管畸形者6例,余60例均能显示病变的范围、血供情况及其特征。12例髓内动静脉畸形、17例硬脊膜动静脉瘘和9例髓周动静脉瘘接受了栓塞治疗,其愈显率分别为58.3%、64.7%和66.7%。所有栓塞病例均无严重并发症发生。结论:经选择性血管造影确诊后行栓塞治疗是椎管内血管畸形安全有效的治疗手段。     

How Do We Treat Arteriovenous Malformations (Tips and Tricks)?

Ethanol embolization is sufficient to eliminate or improve symptoms of arteriovenous malformations (AVMs) in a high percentage of patients, but with substantial risk of minor and major complications. Inadvertent embolization must be avoided by superselective catheterization or direct puncture of the nidus. According to the angiographic morphology of the nidus, AVMs of the trunk and extremities can be classified into four types: type I (arterio-venous fistulae), type II (arteriolo-venous fistulae), type IIIa (arteriolo-venulous fistulae without dilation of the fistula), and type IIIb (arteriolo-venulous fistulae with dilation of the fistula). The described angiographic classification provides considerable information concerning the characteristics of AVMs in the body and extremities, the optimal therapeutic approach, and the likely therapeutic outcome.     

经皮血管成形术治疗血液透析动静脉内瘘狭窄或闭塞

目的:探讨经皮血管成形术(PTA)治疗血液透析患者动静脉内瘘狭窄和闭塞的临床效果。方法:对16例动静脉内瘘狭窄和闭塞的血液透析患者行PTA治疗,比较PTA治疗前后的血管造影表现、透析时血流量及静脉压的变化情况。结果:术后血管造影显示狭窄和闭塞的血管扩张、再通,触诊感血管震颤增强。术后第2天透析时血流量升高至200ml/min以上,可完成透析,在血流量为250ml/min时静脉压下降为(110.62±15.71)mmHg;其中2例分别在术后3个月和6个月发生再狭窄,再次行PTA后血流量恢复。所有患者均未出现血管破裂、出血、血栓形成等并发症。结论:PTA是治疗动静脉内瘘狭窄和闭塞的有效、安全、微创的方法,可选择适宜的患者采用。     

Spontaneous closure of traumatic arteriovenous fistula.

A case of spontaneous closure of traumatic arteriovenous fistula with large false aneurysm is reported. The diagnosis was proved by follow-up angiographic study. The closure of the aneurysm is explained by thrombosis followed by fibrosis with occlusion at the venous orifice.     

De novo development of a lesion with the appearance of a cavernous malformation adjacent to an existing developmental venous anomaly

A case is presented in which a complex multicystic hemosiderin-containing lesion developed adjacent to a previously documented developmental venous anomaly (venous angioma). This lesion had the characteristic MR imaging appearance of a cavernous malformation. Follow-up MR imaging demonstrated a decrease in both the size and complexity of this lesion, which suggests at least a portion of the lesion was due to sequelae of hemorrhage. This case further supports the association of a de novo, hemosiderin-containing lesion in association with developmental venous anomaly. Implications of these findings are that the commonly seen "cavernous malformations" in association with developmental venous anomaly are acquired lesions, and not congenital in origin. A review of the literature discussing the etiology of cavernous malformations and their reported association with the developmental venous anomaly is provided.     

Value of acute-phase angiography in the detection of vascular injuries caused by gunshot wounds to the head: analysis of 12 cases.

A study of the angiographic findings in consecutive civilian patients with cranial gunshot wounds examined in the acute stage has not been done. Most prior clinical studies have evaluated the findings in survivors in the subacute or chronic stages and have often been of war-time casualties. We determined the clinicoradiologic features of six cases of posttraumatic intracranial aneurysm, vascular occlusion, or arteriovenous fistula caused by penetrating missiles among 12 civilian patients who were examined in the acute posttraumatic stage (within 48 hr of injury) during a 1-year period. Three internal carotid/vertebral artery aneurysms, one external carotid artery aneurysm, one combined aneurysm/arteriovenous fistula of the vertebrobasilar circulation, and one cerebral venous occlusion were identified. The 50% overall prevalence of major vascular lesions in this series of civilian patients with penetrating missile injuries examined in the acute stage suggests these injuries are more common than previously suspected. It may indicate that selective cerebral angiography should be considered in the evaluation of the cranial vascular system of such persons.     

Congenital arteriovenous fistulas supplied by a single branch of the maxillary artery.

We report four cases (two children, two adults) of congenital arteriovenous fistula supplied by a single large (pterygoid) branch of the second part of the maxillary artery deep to the parotid gland and mandible, with emphasis on the angiographic findings, therapeutic implications, and cause, with a review of the literature. Awareness of a predilection of congenital arteriovenous fistulas for this site, excellent-quality selective angiography, and careful attention to flow patterns help make the correct diagnosis. Endovascular balloon occlusion is the preferred treatment.     

Regional association of developmental venous anomalies with angiographically occult vascular malformations

This study reviews the neuroradiological findings of 43 patients with a developmental venous anomaly In in order to the clinical significance of this entity. All patients underwent unenhanced and contrast-enhanced computer tomography and magnetic resonance tomography, as well as selective angiography, and were followed for at least 2 years In 40% (17 of 43) of patients a cryptic vascular malformation found In the proximity to the developmentmental venous anomaly. Neurolo gical symptoms were present in 8 of 17 patients (47%) in this group. Patients with an isolated developmental venous anomaly had symptoms in 19% (5 of 26), but none of them had experienced a hemorrhage. Magnetic resonance was the most sensitive method for the diagnose of both types of lesions and alterations of the adjacent parenchyma. These results further support that developmental venous anomalies represent a clinically benign entity. However, patient, with an sociation of a developmental venous anomaly and a cryptic vascular malformation are at risk for hemorage from their angiographically occult vascular malformation. Magnetic resonance proved to be the imaging modality of choice for both entities and is appropriate for diagnosis and follow-up.     

Spinal Dural Arteriovenous Fistula: Imaging Features and Its Mimics

Spinal dural arteriovenous fistula (SDAVF) is the most common spinal vascular malformation, however it is still rare and underdiagnosed. Magnetic resonance imaging findings such as spinal cord edema and dilated and tortuous perimedullary veins play a pivotal role in the confirmation of the diagnosis. However, spinal angiography remains the gold standard in the diagnosis of SDAVF. Classic angiographic findings of SDAVF are early filling of radicular veins, delayed venous return, and an extensive network of dilated perimedullary venous plexus. A series of angiograms of SDAVF at different locations along the spinal column, and mimics of serpentine perimedullary venous plexus on MR images, are demonstrated. Thorough knowledge of SDAVF aids correct diagnosis and prevents irreversible complications.     

Dynamic 3D MR angiography of intra- and extracranial vascular malformations at 3T: a technical note

Time-resolved, contrast-enhanced 3D MR angiography combined with parallel imaging at 3T was applied to an intracranial arteriovenous malformation, a dural arteriovenous fistula, and an extracranial facial arteriovenous malformation. The temporal resolution was one image every 1.5 seconds. Arterial feeders were depicted in all three cases. Early venous drainage was observed in the intracerebral arteriovenous malformation and the dural arteriovenous fistula, but not in the facial arteriovenous malformation. All findings were concordant with conventional angiography.     

血液透析患者上肢动静脉内瘘狭窄或闭塞的介入治疗

目的探讨经皮球囊导管血管成形术治疗上肢动静脉内瘘狭窄和闭塞的疗效。方法14例上肢动静脉内瘘狭窄和闭塞的患者,对比术前和术后的临床表现、彩色多普勒超声、血透时血流量的改变及血管造影改变。结果所有病例经球囊扩张后,狭窄段明显扩张,闭塞处再通,经造影证实狭窄小于30%。结论球囊成形术是治疗动静脉内瘘狭窄和闭塞的有效方法,其操作简单、创伤小、安全、近期效果明显。     

急性动静脉内瘘血栓形成的置管溶栓治疗

目的探讨透析用动静脉内瘘急性血栓形成的置管溶栓治疗的方法及临床价值。方法 2008年1月至2011年1月治疗50例患者发生的67例次急性动静脉内瘘血栓形成。经股动脉插管行上肢动脉造影明确诊断,先用泥鳅导丝行血栓闭塞段导丝穿通术,然后经导管团注尿激酶25万u,如果血栓不能完全清除则保留导管持续泵入尿激酶1～3 d,置管溶栓治疗后24、48、72 h行造影复查,如血管造影显示血栓完全溶解则终止溶栓。结果 67例次急性动静脉内瘘急性血栓形成中,8例次经过尿激酶团注治疗透析道恢复通畅;在置管溶栓后24、48、72 h造影复查时分别有34例次、18例次及5例次显示血栓完全溶解而停止溶栓治疗;2例次溶栓治疗失败。所有病例在置管溶栓过程中均未出现肺栓塞及出血等并发症。结论置管溶栓治疗急性动静脉内瘘血栓形成具有操作简便、疗效肯定、微创、安全的特点,具有较高的临床应用价值。     

脑动静脉畸形供血方式与栓塞的关系研究

目的探讨脑动静脉畸形供血方式与栓塞的关系。方法回顾性分析12 4例4 0 0次超选择性微导管造影所显示的脑动静脉畸形的供血方式及其栓塞后并发症的发生率。结果4 0 0次微导管超选择性造影显示终末型供血方式2 92次,占73% ,穿枝型供血方式2 8次,占7% ,动静脉直接交通型36次,占9%。畸形血管团内伴有动脉瘤2 4例,占6 %。畸形血管团内含有静脉瘤或引流静脉呈瘤样扩张者2 0例,占5 %。除穿枝型供血方式16例未行栓塞外,余者栓塞后无严重并发症发生。结论了解脑动静脉畸形供血方式便可知道能否安全的进行栓塞,而测定脑动静脉畸形的动静脉循环时间可指导栓塞用胶的配制浓度。     

Spinal dural arteriovenous fistula localization with a technique of first-pass gadolinium-enhanced MR angiography: initial experience

Nine patients with initial magnetic resonance (MR) imaging and clinical findings suggestive of spinal dural arteriovenous fistula (AVF) underwent spinal MR angiography with an autotriggered elliptic centric ordered three-dimensional gadolinium-enhanced technique (hereafter, this MR angiographic technique) before conventional intraarterial angiography. In all nine patients, findings with this MR angiographic technique correctly and precisely localized the spinal dural AVF. Observer error resulted in one case in which the site of the fistula was not prospectively reported but was easily identified retrospectively on the spinal MR angiogram.     

Angiographic findings in two cases of aneurysmal malformation of vein of Galen prior to spontaneous thrombosis: therapeutic implications.

Two cases of aneurysmal malformations of the vein of Galen with later spontaneous thrombosis are reported. Angiograms before thrombosis in both cases showed mural type aneurysmal malformations of the vein of Galen with slow arteriovenous shunts and associated stagnation of contrast in the venous sac secondary to severe outflow restriction. Based on these angiographic findings, the patients were managed conservatively and the arteriovenous malformations of the vein of Galen thrombosed with good clinical outcomes. Twenty cases of spontaneous thrombosis previously reported in the literature are reviewed.     

Venous infarctions

Summary Strokes of venous origin are relatively unfrequent. They usually cause venous infarcts which can be observed in 2 main circumstances: cerebral thrombophlebitis or dural arteriovenous (AV) fistulae draining into cerebral veins. The authors study the CT and angiographic aspects of these venous infarcts and their evolution. Conventional angiography remains indispensable to confirm the diagnosis.     

Aneurysms related to cerebral arteriovenous malformations: superselective angiographic assessment in 58 patients.

PURPOSETo report the comprehensive superselective angiographic characteristics of aneurysms associated with cerebral arteriovenous malformations.METHODOne hundred consecutive patients referred for cerebral arteriovenous malformation embolization underwent preembolization superselective angiography. Superselective angiograms were obtained after microcatheterization of arteriovenous malformation pedicles, and assessed for number and location of aneurysms related to the malformation. A chi 2 test was conducted to correlate these parameters with the onset of intracranial hemorrhage.RESULTSAneurysms were demonstrated in 58 of 100 patients. Single aneurysms were found in 24 patients and multiple aneurysms in 34. Presence and number of aneurysms were found to correlate significantly with a clinical presentation of hemorrhage.CONCLUSIONSuperselective angiography was found to be of paramount importance in elucidating the precise and detailed angioarchitecture of brain arteriovenous malformations.     

颅内动静脉瘘的CT和MRI诊断价值

目的:探讨CT和MRI对颅内动静脉瘘的诊断价值。方法:回顾性分析18例颅内动静脉瘘的CT和MRI表现。18例均经DSA检查明确诊断。其中12例行CT检查;16例行MRI检查,同期6例行MRA检查。结果:颅内动静脉瘘的CT和MRI的特征性表现为脑沟、脑裂、基底池内血管影增粗、增多,呈散在分布,受累及的静脉窦增粗,且病变区没有畸形血管团。海绵窦硬脑膜动静脉瘘在T2WI上表现为局部流空信号增宽,MRA原始图像显示局部有较丰富的异常纤细血流信号。结论:认识颅内动静脉瘘的CT和MRI表现,有助于早期诊断及治疗。MRI对显示软脑膜血管扩张优于CT。选择性脑血管造影是确诊本病的可靠手段。     

MRI detection of a female pelvic arteriovenous fistula after hysterectomy: treatment with superselective coil embolisation

We present a rare case of acquired pelvic arteriovenous fistula of the uterine vessels in a woman with a remote history of hysterectomy who presented with chronic pelvic and left limb pain. It was successfully treated by coil embolisation of the left uterine artery. The MRI and angiographic features are described, together with the current management and a review of literature.