A Retrograde Transvenous Embolization Technique with Balloon-Assisted Arterial Aspiration for a Peripheral Arteriovenous Malformation with a Venous Pouch

Management of arteriovenous malformations (AVMs) is challenging, and there is no consensus regarding either the ideal approach or the treatment timing. Percutaneous embolization is the most frequent approach currently used and is considered the first-line technique for AVMs. There is an ongoing discussion about the best technical approach to embolize AVMs. AVMs associated with a dominant outflow vein (DOV) are rare. Embolization of both the DOV and the nidus is considered more effective. Herein, we report a novel technique of transvenous embolization of a DOV under negative pressure from an arterial balloon catheter in a case of a peripheral AVM. This technique allows the embolization of the DOV and the nidus retrogradely.     

Dominant-hemisphere arteriovenous malformations: therapeutic embolization with isobutyl-2-cyanoacrylate

Embolization treatment of 16 patients with dominant-hemisphere arteriovenous malformations (AVMs) is described. This group was selected from 50 patients with brain AVMs embolized with isobutyl 2-cyanoacrylate (IBC-2) over a period of 3 years. All 16 AVMs were cortical in location; six involved the rolandic and speech areas, and four had a deep component. Ten AVMs were embolized through a transfemoral approach, an intraoperative approach was used for four cases, and a combined transfemoral/intraoperative approach was used in two cases. Complete obliteration of the AVM was obtained in one case. Partial obliteration and complete surgical resection was obtained in three cases. Obliteration of 70%-95% of the AVM was obtained in six cases and 45%-70% of the AVM was obliterated in six cases. IBC-2 embolization of the venous drainage was observed in three cases. After embolization, eight patients remained neurologically unchanged. Three patients had mild neurologic deficits that resolved completely within 48 hr; one had a deficit that cleared up 1 week later; and one had a deficit that disappeared within 6 months. In three patients a mild permanent neurologic deficit was evident 6 months after embolization.     

Uterine arteriovenous malformations: the role of intravenous 'dual-phase' CT angiography

The authors describe the use of dual-phase intravenous CT angiography of the pelvis in two female patients, who presented with ongoing excessive vaginal bleeding, to demonstrate large adnexal and uterine arteriovenous malformations (AVMs). Power Doppler was used as the initial modality to diagnose the AVMs. CT angiography, along with 3-D rendering in the form of maximum intensity projections and shaded surface display, were especially useful for anatomical conceptualization to the gynecologist. This greatly helped in the subsequent management in the form of therapeutic embolization in both patients by reducing the time, radiation dose, and contrast required for the procedure. Subsequent surgery, which was required in both patients (due to failed embolization), was also greatly aided by the demonstration of the exact extent of the AVMs on axial CT images. Thus, CT angiography emerged as an impressive non-invasive imaging modality for the complete evaluation and management of the uterine AVMs.     

Retrograde Transvenous Ethanol Embolization of High-flow Peripheral Arteriovenous Malformations

Purpose

To report the clinical efficiency and complications in patients treated with retrograde transvenous ethanol embolization of high-flow peripheral arteriovenous malformations (AVMs). Retrograde transvenous ethanol embolization of high-flow AVMs is a technique that can be used to treat AVMs with a dominant outflow vein whenever conventional interventional procedures have proved insufficient.

Methods

This is a retrospective study of the clinical effectiveness and complications of retrograde embolization in five patients who had previously undergone multiple arterial embolization procedures without clinical success.

Results

Clinical outcomes were good in all patients but were achieved at the cost of serious, although transient, complications in three patients.

Conclusion

Retrograde transvenous ethanol embolization is a highly effective therapy for high-flow AVMs. However, because of the high complication rate, it should be reserved as a last resort, to be used after conventional treatment options have failed.     

Obstetric iatrogenic arterial injuries of the uterus: diagnosis with US and treatment with transcatheter arterial embolization.

Uterine curettage or surgical trauma can cause uterine vascular abnormalities, including pseudoaneurysms, acquired arteriovenous malformations (AVMs), arteriovenous fistulas, and rupture of vessels. Recognition of these abnormalities as the cause of hemorrhage is important, since these abnormalities can be treated safely and effectively with transcatheter arterial embolization but may be worsened by uterine curettage, precipitating massive uterine bleeding. Ultrasonography (US) is the most commonly performed initial imaging examination for evaluation of abnormal uterine bleeding. Color and duplex Doppler US allows convincing detection and diagnosis of these vascular abnormalities and helps differentiate vascular abnormalities that require embolization from nonvascular abnormalities. In cases of pseudoaneurysms, color and duplex Doppler US shows a blood-filled cystic structure with swirling arterial flow. In cases of AVMs, color Doppler US shows an intense vascular tangle, whereas duplex Doppler US shows low-resistance, high-velocity arterial flow. Cases of an AVM combined with a pseudoaneurysm demonstrate the findings of both AVMs and pseudoaneurysms. Transcatheter arterial embolization after angiography is the therapy of choice for these vascular abnormalities, with the advantage of retained reproductive capacity. Routine use of color and duplex Doppler US during examination of abnormal uterine bleeding is recommended to identify and characterize the vascular abnormality.     

Pressure measurements in arterial feeders of brain arteriovenous malformations before and after endovascular embolization

Arteriovenous malformations (AVMs) are composed of abnormal arterial and venous vessels in the brain causing arteriovenous shunts of arterialized blood directly from pial arteries to draining veins. The hemodynamics of these lesions is not well-understood. Changes in blood flow and pressure are probably related to the natural history of AVMs and may also play a major role in AVM treatment. In this study intra-arterial pressure was measured in feeding arteries of AVMs using a microcatheter that had been placed for subsequent embolization treatment (201 measurements were performed in 95 patients before and after the embolization procedure). Results show a direct relationship between pressure changes and degree of embolization. Since pressure changes during the embolization procedure are relatively small, it seems unlikely that these changes are the direct cause of rupture and periprocedural bleedings.     

The efficacy of particulate embolization combined with stereotactic radiosurgery for treatment of large arteriovenous malformations of the brain.

PURPOSETo evaluate the efficacy of combined particulate embolization and single-stage stereotactic radiosurgery in the treatment of large arteriovenous malformations (AVMs) of the brain.METHODSTwenty-four patients with large brain AVMs (diameter > 3.0 cm; volume > 14 cm3), who had previously undergone particulate embolization and stereotactic radiosurgery, were retrospectively evaluated 2 or more years after radiosurgery.RESULTSIn 12 (50%) of these patients there was complete AVM obliteration, comparing favorably with a 58% obliteration rate in a group of AVMs having a 4- to 10-cm3 volume, treated by radiosurgery alone. Recanalization of embolized, but not radiated, AVM segments was identified in 3 (12%) patients. However, long-term occlusion was demonstrated in the embolized portions of most AVMs subsequently treated by radiosurgery. Complications included 1 (4%) patient with a mild upper extremity paresis after radiosurgery and 2 (8%) patients with transient neurologic deficits after embolization.CONCLUSIONCombined embolization and stereotactic radiosurgery was more efficacious than radiosurgery alone for large brain AVMs. Recanalization after embolization did occur but was a relatively minor cause of treatment failure.     

Dissolution of isobutyl 2-cyanoacrylate on long-term follow-up

Eight patients with arteriovenous malformations (AVMs) in the basal ganglionic and deep parietooccipital regions and one patient with an AVM in the shoulder region showed resorption of the isobutyl 2-cyanoacrylate cast and recanalization of the arteries after delayed follow-up angiography. All the AVMs were large, had multiple arterial pedicles, and revealed significant obliteration of the AVM immediately after embolotherapy. Although a 50-75% obliteration was achieved immediately after embolization, follow-up angiography 6-20 months later revealed almost the original status. The residual bucrylate cast was disproportionately small compared with the recanalized malformation in seven patients, while in two patients there was no evidence of bucrylate on plain films. Degradation of bucrylate probably is due to the lysosomal activity of the endothelial cells. The results from our nine patients with some degree of resorption of isobutyl 2-cyanoacrylate and six with recanalized AVMs 6-20 months after embolization suggest that operable AVMs should be excised soon after embolotherapy and inoperable AVMs should be embolized as completely as possible.     

Subclassification and Treatment Results of Ethanol Embolotherapy of Type II Arteriovenous Malformations of the Extremity and Body

PurposeTo evaluate the safety and efficacy of ethanol and coil embolization of type II arteriovenous malformation (AVM) according to a new subtype classification.Materials and MethodsEighty-four type II AVMs in the body or extremity of 79 patients who underwent AVM treatment from 1996 to 2017 were retrospectively subclassified according to the angiographic morphology of the draining vein as type IIa (arterioles shunt to focal segment of single draining vein), type IIb (arterioles shunt to venous sac with multiple draining veins), and type IIc (arterioles shunt along long segment of draining vein). Coil and ethanol embolization of the focal or long segment of the draining vein or the venous sac was performed with direct puncture or transvenous approach according to subtype. Treatment outcomes, number of treatment sessions, and complications were analyzed.ResultsAVM cure (ie, complete embolization) rates were 95%, 76%, and 65% in types IIa, IIb, and IIc AVMs, respectively. The cure rate of type IIa AVMs was significantly better than that of type IIc AVMs (P = .015). Median numbers of treatment sessions were 1 in types IIa and IIb AVMs and 2.5 in type IIc AVMs, with a significant difference between type IIc and the other 2 types (P < .05). Minor complications occurred in 20% of patents and major complications occurred in 7%.ConclusionsThe cure rate of type IIa AVMs was significantly better than that of type IIc AVMs, which also required significantly more treatment sessions than the other 2 types.     

Severe postpartum haemorrhage from ruptured pseudoaneurysm: successful treatment with transcatheter arterial embolization

The purpose of this retrospective study was to evaluate the role of transcatheter arterial embolization in the management of severe postpartum haemorrhage due to a ruptured pseudoaneurysm and to analyse the clinical symptoms that may suggest a pseudoaneurysm as a cause of postpartum haemorrhage. A retrospective search of our database disclosed seven women with severe postpartum haemorrhage in whom angiography revealed the presence of a uterine or vaginal artery pseudoaneurysm and who were treated using transcatheter arterial embolization. Clinical files were reviewed for possible clinical findings that could suggest pseudoaneurysm as a cause of bleeding. Angiography revealed extravasation of contrast material in five out of seven patients. Transcatheter arterial embolization allowed to control the bleeding in all patients and subsequently achieve vaginal suture in four patients with vaginal laceration. No complications related to transcatheter arterial embolization were noted. Only two patients had uterine atony, and inefficiency of sulprostone was observed in all patients. Transcatheter arterial embolization is an effective and secure technique for the treatment of severe postpartum haemorrhage due to uterine or vaginal artery pseudoaneurysm. Ineffectiveness of suprostone and absence of uterine atony should raise the possibility of a ruptured pseudoaneurysm.     

经静脉途径治疗脑动静脉畸形的研究进展

脑动静脉畸形（AVMs）是胎儿期脑血管形成异常的先天性疾病。传统的手术治疗方法包括微创外科、立体放射外科、经动脉血管内栓塞,以解决引起脑出血的病灶,同时尽可能不损害正常的供血动脉和引流静脉为治疗原则。近年来随着经静脉途径介入治疗硬脑膜动静脉瘘和外周血管畸形的成功实施,经静脉途径介入治疗技术逐渐被运用于AVMs的治疗。虽然仍具有挑战和风险,但是已有多个中心相继报道成功案例。本文主要对经静脉途径治疗脑动静脉畸形的文献进行回顾性分析,综述该方法在治疗AVMs方面的研究进展。     

Spontaneous Hemothorax in Neurofibromatosis Treated with Percutaneous Embolization

We evaluated the effectiveness of transcatheter arterial coil embolization therapy for the treatment of spontaneous hemothorax followed by aneurysm rupture in neurofibromatosis patients. Three patients were treated for massive hemothorax caused by arterial lesions associated with neurofibromatosis. Bleeding episodes were secondary to ascending cervical artery aneurysm and dissection of vertebral artery in 1 patient, and intercostal artery aneurysm with or without arteriovenous fistula in 2 patients. Patients were treated by transarterial coil embolization combined with chest drainage. In 1 patient, the ruptured ascending cervical artery aneurysm was well embolized but, shortly after the embolization, fatal hemorrhage induced by dissection of the vertebral artery occurred and the patient died. In the other 2 patients, the ruptured intercostal artery aneurysm was well embolized and they were successfully treated and discharged. Transcatheter arterial coil embolization therapy is an effective method for the treatment of spontaneous hemothorax followed by aneurysm rupture in neurofibromatosis patients.     

Ruptured brain arteriovenous malformations associated with aneurysms: safety and efficacy of selective embolization in the acute phase of hemorrhage

Introduction

The impact of targeted embolization of ruptured cerebral arteriovenous malformation (AVM)-associated arterial aneurysms in the acute phase of bleeding is not well known. The objective of our study was to analyze the safety and efficacy of this treatment strategy with special emphasis on its protective effect against rebleeding.

Methods

From a prospective database, all patients presenting between December 2005 and March 2012 with a ruptured cerebral AVM associated with arterial aneurysms contiguous to the hemorrhage were selected. Hemorrhagic stroke severity and clinical outcome were measured using, respectively, Glasgow Coma Scale (GCS) and modified Rankin Scale (mRS) scores.

Results

Twenty-five patients with ruptured cerebral AVMs associated with 31 arterial aneurysms contiguous with the hemorrhage were included. In the first group of 17 patients, the mean time to treatment was 30.1 h, while in the second group with 1 patient in poor initial clinical conditions and 7 admitted 7 to 28 days after bleeding, it was 17 days. All arterial aneurysms were totally occluded. Four patients presented rebleeding before treatment (mean interval 9.6 days) and four had rebleeding after treatment (mean interval 8.25 months). At a mean follow-up of 56 months, 21 patients were alive (19 mRS?≤?2, 2 mRS?>?2). Three patients died 2 days, 9 days, and 2 months after bleeding and another died of rebleeding of her residual AVM 19 months after treatment. Treatment-related morbidity and mortality were, respectively, 4 and 0 %.

Conclusion

Selective embolization of arterial aneurysms associated with ruptured AVMs is a safe procedure and could lower the immediate risk of rebleeding.     

MR动态减影血管造影在脑动静脉畸形治疗前后中的评价

目的评价MR动态减影血管造影（MR-DSA）在脑动静脉畸形（AVM）栓塞治疗前后的价值和限度。方法22例AVM患者，在栓塞前后均行MR—DSA、三维增强MR血管造影（3D—CEMRA）、MR质子加权成像（PWI）和DSA检查，同时由2名有经验的医生独立进行双盲对照研究。结果MR-DSA和DSA在22例AVM栓塞前后的瘤巢大小及分类上结果一致，MR—DSA能够显示AVM栓塞后的血液动力学改变，瘤巢及引流静脉显影推迟17例，瘤巢变小13例（其中完全消失4例），与DSA符合率为100％。与DSA相比，MR-DSA没有显示瘤巢内动脉瘤和栓塞后引流静脉及供血动脉直径变小各1例，而3D-CEMRA对此显示清晰。栓塞后的PWI与栓塞前相比，22例均可见不同程度的高信号。结论MR—DSA是1种快速、有效、无创的血管造影检查方法，能提供AVM栓塞前后的血流动力学信息，MR—DSA、3D-CEMRA和PWI应在AVM的随访中相互结合，综合运用。     

Transdural blood supply to cerebral arteriovenous malformations adjacent to the dura mater

BACKGROUND AND PURPOSE: Subpial cerebral arteriovenous malformations (AVMs) can develop a transdural arterial blood supply. The relationships between AVM volume, patient age, embolization and prior hemorrhage, and the frequency of transdural blood supply were investigated. METHODS: During 1997-1999, 105 consecutive patients with 107 AVMs adjacent to the dura mater were treated with embolization at one center. One of the authors, who was not directly involved in the treatment, retrospectively reviewed the angiograms. Patient histories were collected from hospital records. RESULTS: Angiograms obtained before the first embolization included a selective injection into the dural arteries in 86 (80%) AVMs. Thirty-six (42%) of those had transdural blood supply. The frequency increased with AVM volume and patient age but not with intracranial hemorrhage. Follow-up angiograms obtained subsequent to at least one embolization were available in 32 patients who had no transdural blood supply at the first examination. In eight (25%) patients, a transdural blood supply developed during a mean treatment time of 12 months. CONCLUSION: A transdural blood supply is common in AVMs adjacent to the dura mater. The frequency increases with AVM volume and patient age. Intracranial hemorrhage does not seem to be a predisposing event. Transarterial embolization appears to induce factors that promote the development of a transdural blood supply.     

Absolute Ethanol Embolization of Lip Arteriovenous Malformations: Observational Results from 10 Years of Experience

PurposeTo evaluate the safety and efficacy of ethanol embolization of lip arteriovenous malformations (AVMs).Materials and MethodsSeventy-six patients with lip AVMs were treated with 173 ethanol embolization procedures. Lip AVMs were treated with direct puncture alone in 21 patients (35 procedures, 20.2%), transarterial embolization alone in 13 patients (18 procedures, 10.4 %), and a combination of both in 60 patients (120 procedures, 69.3%). Adjunctive surgical resection was performed after embolization for cosmetic purposes based on the patient’s request, including patient preference, functional impairment, and skin necrosis. The mean duration of follow-up was 30.9 months ± 27.6. The follow-up included clinic visits and telephonic questionnaires to evaluate the clinical signs and symptoms of AVMs as well as quality of life measures.ResultsOf 76 patients, 51 showed 100% devascularization of AVMs, as determined using arteriography, followed by 23 with 76%–99% devascularization and 2 with 50%–75% devascularization. Of the 76 patients, 40 achieved complete symptom relief and 25 achieved major improvements in cosmetic deformity after embolization. Additionally, 54 patients achieved satisfactory function and aesthetic improvement with ethanol embolotherapy alone, whereas 22 achieved similar outcomes with a combination of ethanol embolotherapy and surgical intervention. Thirty-three adverse events (including 1 major) were documented.ConclusionsEthanol embolization of lip AVMs, as a mainstay, is efficacious in managing these lesions, with acceptable complications. Surgical resection after embolization may improve function and cosmesis in a subset of patients.     

Partial “targeted” embolisation of brain arteriovenous malformations

The treatment of pial arteriovenous brain malformations is controversial. Little is yet known about their natural history, their pathomechanisms and the efficacy and risks of respective proposed treatments. It is known that only complete occlusion of the AVM can exclude future risk of haemorrhage and that the rates of curative embolisation of AVMs with an acceptable periprocedural risk are around 20 to 50%. As outlined in the present article, however, partial, targeted embolisation also plays a role. In acutely ruptured AVMs where the source of bleeding can be identified, targeted embolisation of this compartment may be able to secure the AVM prior to definitive treatment. In unruptured symptomatic AVMs targeted treatment may be employed if a defined pathomechanism can be identified that is related to the clinical symptoms and that can be cured with an acceptable risk via an endovascular approach depending on the individual AVM angioarchitecture. This review article gives examples of pathomechanisms and angioarchitectures that are amenable to this kind of treatment strategy.     

内脏假性动脉瘤出血的栓塞治疗

目的 探讨内脏假性动脉瘤出血经导管栓塞治疗的方法及疗效.方法 回顾性分析7例以不同部位出血为主要表现的患者,行腹、盆腔相关动脉造影,明确出血原因为假性动脉瘤及其部位后行栓塞治疗.结果 7例中,肝动脉瘤2例,胃十二指肠动脉瘤3例,子宫动脉瘤2例.动脉造影能够清晰显示假性动脉瘤的部位、形态和供养血管.DSA造影动脉瘤呈现类圆形囊状突起,栓塞后再次造影见动脉瘤及其供血动脉消失,7例介入治疗均获成功.所有术后出血均停止.结论 DSA造影能明确假性动脉瘤的部位,经导管栓塞治疗假性动脉瘤是安全有效的.     

MR-DSA在评价脑动静脉畸形栓塞前后的价值和限度

目的 评价动态MR血管造影(MR—DSA)在观察脑动静脉畸形栓塞前后的价值和限度。资料与方法 22例脑动静脉畸形患者，在栓塞前后均行MR—DSA、三维增强MR血管造影(3D—CEMRA)、质子加权成像(proton imaging)和数字减影血管造影(DSA)检查，同时由2位有经验的医师独立进行双盲对照研究。结果 MR—DSA和DSA在22例脑动静脉畸形栓塞前后的瘤巢大小及分类上结果一致(100％)，MR—DSA能够显示脑动静脉畸形栓塞后的血流动力学改变，瘤巢及引流静脉延迟显影17例，瘤巢变小13例(其中完全消失4例)，与DSA的符合率为100％。与DSA相比，分别有瘤巢内动脉瘤和栓塞后引流静脉及供血动脉直径变小各1例，MR—四A没有显示，而3D—CEMRA显示清晰。栓塞后的质子加权图像与栓塞前相比，22例均可见不同程度的高信号。结论 MR—DSA是一种快速、有效且无创的血管造影检查方法，能提供脑动静脉畸形栓塞前后的血流动力学信息，MR，DSA、3D—CEMRA和质子加权成像应在脑动静脉畸形的随访中相互结合，综合运用。     

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.