Treatment of high-flow vascular malformations by venous embolization aided by flow occlusion techniques

Embolization of arteriovenous malformations of head and neck: A systematic review

BACKGROUND

Cervicofacial arteriovenous malformations (AVMs) are a significant source of morbidity. Endovascular embolization has emerged as a promising treatment technique for these lesions. However, current literature on cervicofacial AVM embolization mostly consists of single-agent oriented case series, and to date, no comprehensive study has compared the outcomes of available embolic agents.

PURPOSE

To investigate the performance of different embolic agents in the management of cervicofacial AVMs.

METHODS

We systematically searched Ovid MEDLINE, Ovid EMBASE, Ovid Cochrane Central Register of Controlled Trials Scopus, and Web of Science. Studies providing data for the endovascular treatment of cervicofacial AVMs were included. The data regarding complication and cure rates were collected for each embolic agent. Pooled event rates were presented as descriptive statistics.

RESULTS

Eleven studies comprising 204 patients were included in the review. The overall complete and partial cure rates were 62.2% (127/204) and 36.2% (74/204), respectively. Embolization failed to achieve significant improvement in only 1.6% (3/204) of the patients. The complete cure rates were 87.5% (75-100%) for n-Butyl cyanoacrylate (NBCA, glue), 80.5% (61-100%) for Onyx (Medtronic, MN, USA), and 51.5% (18-85%) for ethanol. The overall complication rate was 30% (61/204). The complication rates were 33% (12.5-53%) for ethanol, 14% (0-28%) for Onyx, and 0% for NBCA.

CONCLUSIONS

Our systematic review supports that endovascular embolization is an effective treatment option for cervicofacial AVMs. In our review, the use of Onyx and NBCA was associated with consistently high complete cure rates and a promising safety profile. However, more research is needed to investigate the use of different embolic agents in the treatment of cervicofacial AVMs.

Systemic artery to pulmonary artery aneurysm malformations associated with variants at MCF2L

Arteriovenous malformations (AVM) are characterized by abnormal vessels connecting arteries and veins resulting in a disruption of normal blood flow. Hereditary hemorrhagic telangiectasia (HHT) is the most common cause of pulmonary AVM characterized by a right to left shunt. Here we describe a distinct malformation where the flow of blood was from a systemic artery to the pulmonary artery (PA) resulting in a left to right shunt instead of the right to left shunt seen in individuals with HHT. This distinct malformation was identified in seven probands, one from a multiplex family containing 10 affected individuals from five generations. To identify the molecular basis of this distinct malformation, we performed exome sequencing (ES) on the seven probands and the affected paternal female cousin from the multiplex family. PhenoDB was used to prioritize candidate causative variants along with burden analysis. We describe the clinical and radiological details of the new systemic artery to PA malformation with or without pulmonary artery aneurysm (SA-PA(A)) and recommend distinct treatment techniques. Moreover, ES analysis revealed possible causative variants identified in three families with variants in a novel candidate disease gene, MCF2L. Further functional studies will be necessary to better understand the molecular mechanisms involved on SA-PA(A) malformation, however our findings suggest that MCF2L is a novel disease gene associated with SA-PA(A).

Chest wall systemic artery-to-pulmonary artery vascular malformation treated by embolization of feeders and drainers: A case report

A 74-year-old woman presented with progressive dyspnea. Computed tomography revealed a large systemic artery-to-pulmonary artery vascular malformation (VM) on the right chest wall. Embolization of the VM was performed. First, the main drainers of the VM were retrogradely selected from the segmental pulmonary arteries and embolized using microcoils. Second, 2 main feeders of the VM were selected and embolized with N-butyl cyanoacrylate. Thus, marked flow reduction in the VM was achieved, and the patient's symptom improved dramatically. We believe that embolization of both feeders and drainers is an effective technique for treatment of a chest wall systemic artery-to-pulmonary artery VM.

Peripheral Arteriovenous Malformations: Imaging and Endovascular Management Strategies

The peripheral high-flow vascular malformation (HFVM) comprises arteriovenous malformation (AVM) and fistula (AVF), shows varied clinical presentation (ranging from subtle skin lesion to life-threatening congestive heart failure), and frequently poses diagnostic and therapeutic challenges. Importance of assigning a specific diagnosis to the vascular malformation cannot be overstated, as the treatment strategy is based on the type of vascular anomaly. Although the International Society for the Study of Vascular Anomalies (ISSVA) classification system is the most commonly accepted system for classifying congenital vascular anomalies in clinical practice, the Cho–Do et al classification is of utmost help in guiding optimal mode of treatment in peripheral AVM. Although transarterial approach remains the most commonly employed route for peripheral AVM embolization, the role of transvenous and direct percutaneous approach is ever increasing and the final decision on the approach depends on angioarchitecture of the AVM. In this article, we review various commonly employed classification systems for congenital vascular anomalies, and describe clinical features, imaging and treatment strategies for peripheral arteriovenous malformation (PAVM).

Endovascular Treatment of a Systemic-to-Pulmonary Artery Fistula: A Case Report

Systemic-to-pulmonary artery fistulas are rare. This condition may be congenital, post-traumatic, or post-inflammatory and can cause infection, hemorrhage, or pulmonary hypertension. Here, we report a case of an intercostal-to-pulmonary artery fistula, incidentally detected during the evaluation of dyspnea in a 67-year-old female. Retrograde transcatheter coil embolization in a dilated draining pulmonary artery was initially attempted. However, another draining pulmonary artery developed after 5 months. The intercostal arteries or systemic feeders were successfully embolized through a transarterial access. At the 10-month follow-up, the abnormally dilated vessels had regressed, and dyspnea had improved. Sequential or simultaneous retro- and antegrade transcatheter embolization may successfully treat pleural arterio-arterial fistulas.

Analysis of skin morphological features and real-time monitoring using snapshot hyperspectral imaging

We propose a snapshot hyperspectral imaging system and methods for skin morphological feature analysis and real-time monitoring of skin activities. The analysis method includes a strategy using weighted subtractions between sub-channel images to extract absorption information due to specific chromophores within skin tissue, for example hemoglobin and melanin. Based on morphological analysis results, we carry out real-time monitoring of the skin features to verify the ability of this method to provide temporal responses of the skin tissue activities, which is experimentally shown to be useful in the measurement of heartrate, monitoring of the tissue recovery after a body exercise, and studying of the tissue response due to a vascular occlusion. Compared to conventional multispectral imaging system, the proposed system improves the device simplicity and is immune to motion artifacts. Coupled with the extraction algorithms, the hyperspectral imaging promises a robust skin assessment tool with abilities for qualitative visualization and potentially quantitative analysis of skin features, useful in the applications of cosmetics and clinical dermatology.

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

PURPOSE

To evaluate the safety and efficacy of ethanol and coil embolization of type II arteriovenous malformation (AVM) according to a new subtype classification.

MATERIALS AND METHODS

Eighty-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.

RESULTS

AVM 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%.

CONCLUSIONS

The 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.

Polidocanol Sclerotherapy Combined with Transarterial Embolization Using n-Butyl Cyanoacrylate for Extracranial Arteriovenous Malformations

Purpose

To assess the safety and effectiveness of polidocanol sclerotherapy combined with transarterial embolization using a liquid adhesive agent (n-butyl cyanoacrylate, NBCA) for treatment of extracranial arteriovenous malformations (AVMs).

Materials and Methods

Twenty-three patients with symptomatic AVMs in the head and neck (6), upper (7) and lower extremity (10) with a mean age of 42 years (range 4–74) treated with polidocanol sclerotherapy were retrospectively assessed. AVMs were classified according to the angiographic morphology of the nidus. There were 2 type I, 6 type II, 6 type IIIa and 9 type IIIb. Arterial embolization using NBCA was performed to reduce arterial flow before sclerotherapy. Polidocanol mixed with contrast material or carbon dioxide was delivered by percutaneous direct puncture.

Results

Treatment was successfully performed in all patients. In the mean follow-up period of 38 months, symptoms resolved or improved in 20/23 patients (87.0%). AVMs were devascularized 100% in 2 patients, 76–99% in 13, 50–75% in 7 and < 50% in 1. More than 50% devascularization was seen in 22 patients (95.6%). Two (8%) patients had complete remission, 17 (74%) had partial remission and 3 (13%) had no remission. There was no aggravation. Treatment was considered effective (complete and partial remission) in 20 patients (87.0%). Minor complications including localized arterial thrombosis (2) and spontaneously healing skin ulcer (1) were seen in 2 patients (8.7%). There were no major procedure-related complications.

Conclusion

Polidocanol sclerotherapy combined with transarterial embolization using NBCA is safe and effective for treating extracranial AVMs with an acceptable risk of minor complications.

Absolute Ethanol Embolization Combined with Surgical Resection of Scalp Arteriovenous Malformations: Interim Results

PURPOSE

To assess treatment methods, interim results, and complications of absolute ethanol embolization combined with surgical resection of scalp arteriovenous malformations (AVMs).

MATERIALS AND METHODS

From September 2012 to January 2015, 15 consecutive patients (8 male and 7 female) with scalp AVMs underwent staged ethanol embolizations. Ethanol embolization was performed using transcatheter and/or direct puncture techniques. Ten patients with scalp AVMs with a dominant outflow vein (DOV) also underwent coil deployment before ethanol embolization. Two patients underwent surgical resection after ethanol embolization was achieved. Follow-up evaluations included clinical outcome of symptoms and signs and imaging at 1.5 months, 6 months, and annually thereafter.

RESULTS

In 15 patients, 33 ethanol embolizations were performed; 16 coil deployments were performed in 10 patients who had scalp AVMs with a DOV. Of 15 patients, 8 (53.3%) were cured, 2 of whom underwent surgical resection. All 8 patients showed no recurrence in the follow-up period (range, 12-48 months; mean, 25 months). Seven patients (46.7%) had partial remission and will need further treatment sessions for residual AVMs (range, 1-12 months; mean, 7 months). In 3 of 15 patients (20%), 7 minor complications (skin blisters and necrosis) occurred. All minor complications healed with wound dressing and observation. There were no major complications.

CONCLUSIONS

Ethanol embolization has the potential for cure in management of scalp AVMs, with an acceptable risk of minor and major complications. Once AVMs are devascularized, surgical resection can be performed to improve cosmetic results.

New Treatment Approaches to Arteriovenous Malformations

Arteriovenous malformations (AVMs) are high-flow vascular anomalies that have demonstrated a very high recurrence rate after endovascular treatment, surgical treatment, or a combination of both. Surgical treatments have shown good response when they are small and well localized but a poor response when diffuse. A better understanding of the nature of the lesion has led to a better response rate and a safer treatment for these patients. This has been accomplished through a detailed understanding of the angioarchitecture of the lesion, enabling a tailored approach in reaching and targeting the nidus of the AVM with different liquid embolic agents, more specifically ethanol. Flow reduction techniques help in exposing the nidus to sclerosant agents. A clinical classification, the Schobinger classification, will help determine the appropriate time to start or to pursue therapy.

New Alcohol and Onyx Mixture for Embolization: Feasibility and Proof of Concept in Both In Vitro and In Vivo Models

INTRODUCTION

Onyx and ethanol are well-known embolic and sclerotic agents that are frequently used in embolization. These agents present advantages and disadvantages regarding visibility, injection control and penetration depth. Mixing both products might yield a new product with different characteristics. The aim of this study is to evaluate the injectability, radiopacity, and mechanical and occlusive properties of different mixtures of Onyx 18 and ethanol in vitro and in vivo (in a swine model).

MATERIALS AND METHODS

Various Onyx 18 and ethanol formulations were prepared and tested in vitro for their injectability, solidification rate and shrinkage, cohesion and occlusive properties. In vivo tests were performed using 3 swine. Ease of injection, radiopacity, cohesiveness and penetration were analyzed using fluoroscopy and high-resolution CT.

RESULTS

All mixtures were easy to inject through a microcatheter with no resistance or blockage in vitro and in vivo. The 50%-ethanol mixture showed delayed copolymerization with fragmentation and proximal occlusion. The 75%-ethanol mixture showed poor radiopacity in vivo and was not tested in vitro. The 25%-ethanol mixture showed good occlusive properties and accepted penetration and radiopacity.

CONCLUSION

Mixing Onyx and ethanol is feasible. The mixture of 25% of ethanol and 75% of Onyx 18 could be a new sclero-embolic agent. Further research is needed to study the chemical changes of the mixture, to confirm the significance of the added sclerotic effect and to find out the ideal mixture percentages.

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.

Embolization of Congenital Renal Arteriovenous Malformations Using Ethanol and Coil Depending on Angiographic Types

PURPOSE

To evaluate effectiveness and safety of embolization of congenital renal arteriovenous malformations (AVMs) using ethanol and/or coil according to angiographic type.

MATERIALS AND METHODS

Between August 2010 and October 2015, 11 patients (13 sessions; 10 women and 1 man; mean age, 50.8 y) with congenital renal AVMs were treated using ethanol and/or coils via 2 approaches (transarterial access or direct puncture). Demographics, clinical findings, diagnostic modalities, angiographic types, technical and clinical success rates, and complications were reviewed. Renal AVMs were classified into 3 angiographic types, and treatment was based on this classification.

RESULTS

Technical success rate was 91% (10/11), and clinical success rate was 100% (11/11). Of patients, 7 had type III AVMs, 3 had type I AVMs, and 1 had type II AVM. Embolic agents were ethanol in 5 patients, coils with ethanol in 3 patients, and coils in 3 patients. Of the 8 patients treated with ethanol, 6 had infarcted renal areas of 3.5%-30% (mean, 14.6%). After a mean follow-up period of 16.3 months, there was no evidence of recurrent AVMs on imaging or laboratory studies.

CONCLUSIONS

Embolization of congenital renal AVMs via transarterial or direct percutaneous approaches using ethanol and/or coils based on a simple angiographic classification was safe and effective and elicited good outcomes. Most of the patients with congenital renal AVMs were women.

Salvage treatment of hemorrhagic arteriovenous malformations in jaws

OBJECTIVE

To present our clinical experience on embolotherapy of arteriovenous malformations (AVMs) in jaws with acute hemorrhage.

MATERIALS AND METHODS

Twelve patients with a history of hemorrhage were selected for this study. Continuous interdental sling suture, digital pressure on the extraction socket, and iodoform gauze packed into the socket and fixed with sutures to the adjacent gum were used for temporary hemostasis before embolization. Fiberoptic bronchoscopy was used in all cases to facilitate endotracheal intubation. Absolute ethanol combined with coils was used as method of embolization.

RESULTS

Eight patients presented with intermittent interdental gum bleeding or controlled hemostasis before embolization. Four patients presented with torrential hemorrhage around the tooth, controlled by continuous pressure on the tooth and bilateral gum for temporary hemostasis. All patients were successfully salvaged before embolization. Ten of 12 patients were cured, and 2 had partial remission. Follow-up ranged from 12 to 26 months (mean, 16.5 months) for all patients, and there was no recurrence of the lesions.

CONCLUSIONS

The treatment of hemorrhagic AVMs of the jaw requires a multidisciplinary team approach; such cases can be successfully salvaged and stably controlled by embolization with coils and absolute ethanol.

Iatrogenic percutaneous vascular injuries: clinical presentation, imaging, and management

Vascular interventional radiology procedures are relatively safe compared with analogous surgical procedures, with overall major complication rates of less than 1%. However, major vascular injuries resulting from these procedures may lead to significant morbidity and mortality. This review will discuss the etiology, clinical presentation, diagnosis, and management of vascular complications related to percutaneous vascular interventions. Early recognition of these complications and familiarity with treatment options are essential skills for the interventional radiologist.

Pelvic vascular malformations

Vascular malformations (VMs) comprise a wide spectrum of lesions that are classified by content and flow characteristics. These lesions, occurring in both focal and diffuse forms, can involve any organ and tissue plane and can cause significant morbidity in both children and adults. Since treatment strategy depends on the type of malformation, correct diagnosis and classification of a vascular lesion are crucial. Slow-flow VMs (venous and lymphatic malformations) are often treated by sclerotherapy, whereas fast-flow lesions (arteriovenous malformations) are generally managed with embolization. In addition, some cases of VMs are best treated surgically. This review will present an overview of VMs in the female pelvis as well as a discussion of endovascular therapeutic techniques.

Guidelines for the use of NBCA in vascular embolization devised by the Committee of Practice Guidelines of the Japanese Society of Interventional Radiology (CGJSIR), 2012 edition

Cyanoacrylates are a group of fast-acting adhesives. They form low viscosity liquids in the monomer state and instantly polymerize to become adhesive upon contact with ionic substances. Since the 1950s, they have been used around the world for industrial and household purposes. N-butyl cyanoacrylate (NBCA) is a cyanoacrylate that is commonly used for medical care, and the closure of skin wounds with NBCA has been found to promote hemostasis. However, in Japan, the intravascular injection of NBCA is considered to be off-label use, except during the treatment of gastric varices under endoscopy. The use of NBCA in embolotherapy is considered when the target vessels cannot be cannulated superselectively, for vascular diseases that require long segments of the target vessel to be embolized, or for patients in a hypocoagulable state. NBCA-based embolotherapy can be used to treat vascular malformations, acute hemorrhaging, tumors, and venous disease. The complications associated with NBCA-based embolotherapy include tissue ischemia, hemorrhaging, systemic or local reactions, and catheter adhesion to blood vessels. NBCA is mixed with Lipiodol to make it radiopaque and to adjust its polymerization time. Since there are various technical aspects to performing NBCA-based embolotherapy safely, it should be carried out by, or with the assistance of, proficient interventional radiologists.

Ethanolamine oleate sclerotherapy combined with transarterial embolization using n-butyl cyanoacrylate for extracranial arteriovenous malformations

PURPOSE

This study was designed to assess the safety and effectiveness of ethanolamine oleate (EO) sclerotherapy combined with transarterial embolization using a liquid adhesive agent (n-butyl cyanoacrylate, NBCA) for treatment of extracranial arteriovenous malformations (AVMs).

METHODS

Twenty-four patients with symptomatic AVMs in the head and neck (n = 15), extremity (n = 5), and trunk (n = 4) with a mean age of 44 years (range, 18-78) treated with EO sclerotherapy were retrospectively assessed. AVMs were classified according to the angiographic morphology of the nidus. There were 7 type II (arteriolovenous fistulae), 6 type IIIa (arteriolovenulous fistulae with nondilated fistula), and 11 type IIIb (arteriolovenulous fistulae with dilated fistula). Transarterial embolization using NBCA was performed to reduce arterial flow before sclerotherapy. EO mixed with contrast material was delivered by percutaneous direct puncture or by catheterization into the draining vein under balloon occlusion.

RESULTS

Three (13%) of 24 patients were cured, 17 (71%) had partial remission, and 4 (16%) no remission. Treatment was considered effective (cure and partial remission) in 20 patients (83%). Four patients (16%) experienced transient minor complications, including self-healing skin ulcer (n = 3) and localized deep venous thrombosis (n = 1). There were no major complications.

CONCLUSIONS

EO sclerotherapy combined with transarterial embolization using NBCA is safe and effective for treating extracranial AVMs with an acceptable risk of minor complications.

Vascular access complications: diagnosis and management

OPINION STATEMENT

The incidence of vascular access site related complications ranges between 0.8 % to 1.8 % of diagnostic cardiac catheterization and up to 9 % of percutaneous coronary interventions (PCI) [1]. The femoral vessels at the groin are used as the access site for the majority of percutaneous coronary, peripheral arterial and venous, and electrophysiologic interventions. With emergence of endovascular abdominal aortic aneurysm repair (EVAR), thoracic endovascular aneurysm repair (TEVAR), and transcatheter aortic valve replacement (TAVR), larger access sheaths (up to 18Fr-24Fr) are required, which further increases the potential for access site complications. The true incidence of access site complications arising from non-coronary interventions is unknown; hence it is likely that the total incidence of vascular access site complications is greatly underestimated. Vascular closure devices (VCDs), radial artery access, fluoroscopic guidance, and ultrasound guidance have all been used with a hope to minimize these complications. Despite these attempts, vascular access complications have not been eliminated. Cardiovascular specialists must promptly identify these complications and manage them appropriately.

A Step-by-Step Practical Approach to Imaging Diagnosis and Interventional Radiologic Therapy in Vascular Malformations

Within vascular anomalies, vascular malformations are those present at birth that grow with the patient and exhibit abnormal dilated vascular channels lined by mature endothelium. Vascular tumors, the other group of vascular anomalies, demonstrate endothelial hypercellularity. Vascular malformations are further divided into low-flow varieties (capillary, venous, and lymphatic malformations) and high-flow varieties (arteriovenous malformation and fistula). All malformations exhibit a predictable group of clinical patterns that vary in severity and rate of progression. The interventional radiologist must incorporate this clinical data with characteristic ultrasound and magnetic resonance findings to arrive at a diagnosis. One must then decide in a multidisciplinary fashion, based on objective clinical criteria and image-based morphology, if the patent is a candidate for intervention. Sclerotherapy is a technique used to treat vascular malformations whereby an endothelial-cidal agent is introduced into the endoluminal compartment to initiate vascular closure. The high flow rate of an arteriovenous malformation requires the incorporation of superselective transarterial, direct, and transvenous access with flow reduction techniques to deliver adequate dose of sclerosant and embolic to the nidus. Satisfactory outcomes are seen in over half of all malformations patients. Similar treatment-related complications are seen between malformations but are lowest in lymphatic and highest in arteriovenous malformations.

Pediatric vascular malformations: pathophysiology, diagnosis, and the role of interventional radiology

The Mulliken and Glowacki classification (1982) differentiated vascular anomalies into two groups based on their endothelial characteristics: hemangiomas and vascular malformations. Vascular anomalies are localized defects of the vasculature that affect a limited number of vessels in a restricted area of the body. These defects are secondary to errors in vascular morphogenesis. Depending on the type of vessel involved, the vascular malformation group was subdivided into high-flow (such as arteriovenous malformation and arteriovenous fistula) and low-flow lesions (such as venous and lymphatic malformations). Depending on the type of lesion, the location and degree of involvement and the clinical effect, different types of treatment would be required. For the purpose of this review, we concentrate solely on vascular malformations: the clinical features, genetics, diagnosis, and current treatment options.

The surgical management of 73 vascular malformations and preoperative predictive factors of major haemorrhage--a single centre experience

OBJECTIVES

In our series of patients with congenital vascular malformations (CVMs) we investigate the preoperative factors for predicting major haemorrhage at surgery and propose an algorithm for their surgical management.

DESIGN

This is a partly prospective case series of patients with severe symptoms/complications due to CVMs.

MATERIALS AND METHODS

Data were collected on 73 consecutive procedures in 41 patients with CVMs from 1992 to 2006 at a large university hospital and the association of following factors with blood loss during the procedure were investigated: type of procedure, possibility of proximal tourniquet use, lesion flow characteristics, previous history of major haemorrhage with CVM surgery, platelet counts and length of hospital stay.

RESULTS

Significantly higher blood loss was associated with debulking surgery (p=0.006) and with previous history of major haemorrhage during CVM surgery, (p=0.041). Blood loss was higher in lesions where proximal tourniquet application was not possible (p=0.093). High-flow lesions were not strongly associated with major blood loss (p=0.288). Major blood loss (>2l) occurred in 16 (20.8%) procedures performed on 11 (26.2%) patients, but this did not prolong hospital stay.

CONCLUSION

Surgery can potentially improve morbidity/mortality in patients with life/limb-threatening complications or severe symptoms due to CVMs, providing they are managed in multidisciplinary specialised centres.

Peripheral arteriovenous malformations with a dominant outflow vein: results of ethanol embolization

Objective

To assess retrospectively the treatment results of ethanol embolization of peripheral arteriovenous malformations (AVMs) with a dominant outflow vein (DOV).

Materials and Methods

Nineteen patients who had peripheral AVMs with a DOV were enrolled in this study (mean age, 29.7 years; range, 15-42 years). Fifty-one ethanol embolizations (mean, 2.7; range, 1-8) were performed by direct puncture (n = 29), the transarterial approach (n = 13), the transvenous approach (n = 5), or a combination of methods (n = 4) under general anesthesia. Coil and/or core-removed guide wire embolization of the DOV or another flow occlusion technique (i.e., use of an external pneumatic pressure cuff) to achieve vascular stasis were required in all patients during ethanol embolization. Clinical follow-up (mean, 22.2 months; range, 1-53 months) was performed for all patients, and imaging follow-up (mean, 22.1 months; range, 2-53 months) from the last treatment session was performed for 14 patients. The therapeutic outcome (cure, improvement, no change, or aggravation) was assessed according to the clinical response and the degree of devascularization at angiography.

Results

Ethanol embolization was considered as an effective procedure in all patients. Thirteen (68%) of 19 patients were cured and six displayed improvement. Three of six patients with improvement needed further treatment sessions for residual AVMs. Four patients (21%) experienced a total of eight complications. Five complications (three events of a distal embolism and one event each of a urinary bladder necrosis and a brain infarct related to the accidental cannulation of the common carotid artery during insertion of the Swan-Ganz catheter) were major and three complications (skin necrosis) were minor.

Conclusion

Peripheral AVMs with a DOV can be effectively treated with a high cure rate by the use of ethanol embolization alone or in conjunction with the use of coil and/or core-removed guide wire embolization.

Ethanol embolotherapy of pelvic arteriovenous malformations: an initial experience

Objective

We retrospectively assessed the results of performing ethanol embolization for pelvis arteriovenous malformations (AVMs).

Materials and Methods

During the past 10 years, eight patients (8 females, age range: 27-52 years) with AVMs in the pelvic wall (n = 3) and uterus (n = 5) underwent staged ethanol embolizations (range: 1-5, mean: 2.5) under general anesthesia. Ethanol embolization was performed by the use of the transcatheter and/or direct puncture techniques. Clinical follow-up was performed for all of the patients, and imaging follow-up was available for seven patients. The therapeutic outcomes were established by evaluating the clinical outcome of the signs and symptoms, as well as the degree of devascularization observed on post-procedural angiography.

Results

During the 20 sessions of ethanol embolization, the solitary transarterial approach was used 14 times, the transvenous approach was used three times and direct puncture was used once. For two patients, the transarterial and transvenous or direct puncture approaches were used together in one session. For four patients, ethanol and coils were used as embolic agents, and n-butyl cyanoacrylate (NBCA) and ethanol were used in one patient. Seven (88%) of eight patients were cured of their AVMs and one patient (12%) displayed improvement. Major complications were seen in two patients (25%).

Conclusion

Ethanol embolization is effective for the treatment of pelvic arteriovenous malformations, though there is a chance of a major complication.

Traitement radiologique des malformations artérioveineuses périphériques

Management of high-flow arteriovenous malformation remain often problematic. Complete eradication of the nidus is the only potential cure, but this, however, is often difficult if not impossible. Frequently, a multidisciplinary approach is required. In these article, techniques and results of the endovascular management of MAV are discussed.

Arteriovenous Malformations of the Body and Extremities: Analysis of Therapeutic Outcomes and Approaches According to a Modified Angiographic Classification

PURPOSE

To propose a modified angiographic classification for peripheral arteriovenous malformations (AVMs) and to determine its value for assessing therapeutic outcomes and approaches to ethanol embolization of AVMs in the body and extremities.

METHODS

AVMs of the trunk and extremities were categorized according to the angiographic morphology of the nidus: type I (arteriovenous fistulae), type II (arteriolovenous fistulae), type IIIa (arteriolovenulous fistulae with non-dilated fistula), and type IIIb (arteriolovenulous fistulae with dilated fistula). Sixty-six patients (41 women; mean age 28.3 years, range 5-53) with inoperable AVMs in the body and extremities who underwent staged ethanol embolizations were retrospectively analyzed. Therapeutic outcomes and approaches were evaluated according the above classification system.

RESULTS

The 66 AVMs were composed of 30 (45%) type IIIb, 13 (20%) type II, 12 (18%) mixed types IIIa and IIIb, 9 (14%) mixed types II and IIIb, and 2 (3%) type IIIa. Ethanol embolization was most effective for type II (100%), and more effective for type IIIb (83%) than for type IIIa or mixed types (< or = 50%). Despite the use of the transarterial approach, direct puncture and transvenous approaches were more relevant for treating type II AVMs. Only the transarterial approach was used for treating type IIIa; both direct puncture and transarterial approaches were used for treating the other types.

CONCLUSION

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.

Classification, diagnosis, and interventional radiologic management of vascular malformations

Vascular anomalies are comprised of either hemangiomas or vascular malformations.Low-flow vascular malformations can be divided into capillary, venous, and lymphatic types and are usually present at birth, undergo pari passu growth, and produce symptoms related to mass effect or stasis. High-flow malformations are comprised pre-dominantly of arteriovenous malformations that follow a more aggressive clinical course of hyperemia, adjacent mass effect, steal phenomenon, tissue destruction, and ultimately high output failure. Ultrasound, CT, nuclear medicine, angiography, and particularly MRI have greatly enhanced diagnostic accuracy and provide detailed information for percutaneous and surgical treatment planning and an objective means of following therapeutic efficacy. Interventional radiologic percutaneous sclerotherapy for low-flow lesions and embolosclerotherapy for high-flow lesions with or without adjunctive surgical intervention have become the mainstay of therapy.

Ethanol embolization of arteriovenous malformations: interim results

PURPOSE

To assess retrospectively the interim results and the complications of ethanol embolization treatment of arteriovenous malformations (AVMs).

MATERIALS AND METHODS

Institutional review board approval was obtained for a retrospective review of patient medical and imaging records. Informed consent was not required by the institutional review board. Written consent for the procedure was obtained from all patients after a discussion about the advantages and risks of the procedure. After a general anesthetic was administered, 40 patients (16 male, 24 female; age range, 9-53 years) with inoperable AVMs in the body and extremities underwent staged ethanol embolizations (range, 1-24; median, 3). Pulmonary artery pressure and arterial blood pressure were monitored as ethanol was injected. Ethanol embolizations (50%-100% ethanol mixed with nonionic contrast material) were performed by using transcatheter and/or direct puncture techniques. Ten patients underwent additional coil deployment during ethanol embolization. Clinical follow-up (range, 2-48 months; mean, 14.6 months; median, 12 months) was performed in all patients, and results from imaging follow-up (range, 0-48 months; mean, 8.4 months; median, 6 months) were available from the last treatment session in 28 patients. Therapeutic outcomes were established by evaluating the clinical outcome of symptoms and signs, as well as the degree of devascularization at follow-up angiography.

RESULTS

One hundred seventy-five ethanol embolizations were performed in 40 patients. Sixteen (40%) of 40 patients were cured, 11 (28%) had partial remission, seven (18%) had no remission, and one (2%) experienced aggravation. Treatment failed in five patients (12%). Ethanol embolization was considered effective (cure, 16 patients; partial remission, 11 patients) in 27 patients (68%). Eleven patients will need further treatment sessions for residual AVMs. Twenty-one patients (52%) experienced complications. Twenty-seven minor complications (skin and transient peripheral nerve injuries) (27 [15%] of 175 procedures) occurred in 18 (45%) of 40 patients. All minor complications were healed with wound dressing and observation. Five major complications (five [3%] of 175 procedures) occurred in five (12%) of 40 patients, and four patients recovered completely.

CONCLUSION

Ethanol embolization has the potential for cure in the management of AVMs of the body and extremities but with acceptable risk of minor and major complications.