Embolization of high-flow craniofacial vascular malformations with onyx

Ethanol Embolization of Chest Wall Arteriovenous Malformations: Four-Year Findings

OBJECTIVES

To summarize the clinical characteristics and investigate the efficacy of ethanol embolotherapy in the treatment of chest well arteriovenous malformation (AVM). Treatment-associated complications were also explored.

MATERIALS AND METHODS

Between March 2017 and August 2021, 32 consecutive patients (mean age, 23.7 years; age range, 5-54 years) who underwent ethanol embolotherapy for chest well AVMs under general anesthesia were included in this study. Embolization was performed through a direct puncture, transarterial catheterization, or a combination of the 2 procedures. The mean follow-up duration after the last treatment was 18.0 months (range, 3-42 months). The degree of devascularization on follow-up (assessed using angiography or computed tomography), and the clinical signs and symptoms of AVMs were evaluated as the therapeutic outcomes. The major and minor complications associated with the procedures were recorded.

RESULTS

A total of 103 embolization procedures (mean, 3.2; range, 2-7) comprising 101 ethanol embolization and 2 coil embolizations were performed on 32 patients with chest wall AVMs. The AVM nidus was accessed through the transarterial approach alone in 4 patients, by direct puncture in 11, and a combined procedure in 17 patients. Overall, more than 80% of the procedures were performed using the combined approach. Complete AVM devascularization was achieved in 12 (37.5%) patients. Moreover, 76% to 99% AVM was achieved in 18 patients (56.3%), and 50% to 75% in 2 patients (6.3%). Bleeding, pain, heart failure, and cosmetic deformities were the indications for treatment. For 3 patients (3/32, 9.4%) who had bleeding, the treatment stopped the hemorrhage. Complete pain relief was reported in 8 patients (8/32, 25.0%), whereas complete relief from congestive heart failure post-embolization was observed in 5 of the 6 patients with congestive heart failure (5/6, 83.3%). Complete correction of cosmesis deformities after embolization was achieved in 10 patients (10/32, 31.3%). Two patients who underwent surgery to correct persistent deformity after embolization only showed insignificant improvement. In addition, 6 (18.8%) patients developed 13 complications including blister, necrosis, hemothorax, transient hemoglobinuria, and transient pulmonary artery hypertension.

CONCLUSIONS

Ethanol embolotherapy is a safe and effective procedure for chest well AVMs. Surgery is required for some patients with residual cosmesis deformity.

CLINICAL IMPACT

Currently, there is no standard treatment for chest well AVMs due to their rarity and high heterogeneity. The present study shows that thanol embolotherapy is a safe and clinically effective treatment procedure for the chest well AVMs. Transarterial embolization in combination with direct puncture embolization can reach the AVM nidus. Ethanol embolotherapy can achieve complete obliteration of the AVM nidus in the majority of patients. Surgery may still be needed to correct cosmetic deformity after embolization. The present study provides valuable evidence to inform clinical decision-making.

Endovascular treatment for scalp arteriovenous fistulas: prospects and dilemmas

Scalp arteriovenous fistula (AVF) is an anomalous arteriovenous connection without a capillary bed. For symptomatic scalp AVFs, an appropriate treatment must be chosen. Currently, endovascular treatment (EVT) can serve as an alternative to surgical excision. However, EVT of scalp AVFs constitutes a challenge. A standard EVT strategy for scalp AVFs has not yet been established. Therefore, a review of current research on EVT for scalp AVFs is essential. In this review, the following issues were discussed: scalp vessel anatomy; etiology, angioarchitecture and classification of scalp AVFs; EVT principles and techniques; and EVT complications and prognosis. In addition, we attempted to propose a feasible grading system with 4 grades. Based on the literature review and our experience, we found that scalp AVFs have a complex angioarchitecture, which made EVT only possible in specific cases with low-grade scalp AVFs. EVT can be performed by transarterial or transvenous embolization. Direct puncture embolization can also be used for scalp AVFs. Complete occlusion of scalp AVF by EVT had low complication and recurrence rates and a good prognosis.

A Rare Case of Scalp Arteriovenous Malformation in an Adolescent Patient

Scalp arteriovenous malformations (AVMs) are rare lesions that arise due to a pathological fistulous connection between scalp arterial feeders and draining veins without the involvement of capillary beds. Here, we report a case of a 17-year-old male who presented with an enlarging, pulsatile, mass in the scalp of the parietal region with mild headaches and was diagnosed with a scalp AVM that was treated successfully with endovascular trans-arterial embolization. Scalp AVMs are uncommon extracranial vascular abnormalities that neurosurgeons hardly ever see. To precisely define the angiographic architecture of an AVM and to organize further management, digital subtraction angiography is crucial.

Utility of manual venous compression during transvenous Onyx injection for a scalp arteriovenous fistula: illustrative case

BACKGROUND

When performing transvenous liquid embolization for scalp arteriovenous fistulas, multiple networks of venous drainage could limit effective retrograde penetration of embolic agents into feeding arteries, resulting in incomplete obliteration. A salvage technique to achieve effective Onyx penetration with manual venous compression during transvenous embolization is demonstrated.

OBSERVATIONS

A 43-year-old man presented with a progressively enlarging mass on his left temporal scalp that was first noticed approximately 20 years earlier. External carotid artery injection showed two scalp arteriovenous fistulas (AVFs). The patient received endovascular embolization. After successful transarterial obliteration of one AVF, transvenous Onyx embolization was performed for another AVF located in the subcutaneous layer. To avoid unnecessary Onyx migration into multiple venous networks, several coils were put in a venous pouch as a scaffold for the Onyx, and feeding arteries were temporarily occluded. Despite these adjunctive techniques, the Onyx migrated into multiple veins and even toward the orbit without complete fistula obliteration. Thereafter, Onyx was injected under manual compression of venous outlets from the pouch, resulting in complete obliteration.

LESSONS

Manual compression of venous outlets can be used as a salvage procedure during transvenous Onyx embolization for a scalp AVF. A surgeon’s radiation exposure can be reduced by step-by-step adjunctive procedures.

Head and neck arteriovenous malformations: University of Tennessee experience, 2012–2022

OBJECTIVE

Head and neck arteriovenous malformations (AVMs) are complex lesions that represent a subset of vascular anomalies (VAs). The authors present an analysis of their institutional experience managing these lesions as a multidisciplinary team.

METHODS

A retrospective chart review was performed of head and neck AVM patients treated at the authors’ institution from 2012 to 2022. Recorded data included patient demographic characteristics, details of clinical presentation, Schöbinger clinical scale and Yakes AVM classification results, and details of all endovascular and surgical treatments. The primary outcome of the study was clinical response to treatment. Angiographic occlusion and complication rates were reported. Chi-square tests were used for comparative statistics.

RESULTS

Sixteen patients (9 female, 56%) with AVMs of the head and neck presented from age 3 to 77 years. The Schöbinger stage was stage II in 56% of patients (n = 9) and stage III in 44% of patients (n = 7). The Yakes AVM classification was nidus type (2a, 2b, or 4) in 7 patients (43%) and fistula type (1, 3a, or 3b) in 9 patients (57%). The majority of patients (n = 11, 69.0%) were managed with embolization as the only treatment modality, with an average of 1.5 embolizations/patient (range 1–3). Surgical resection was employed in 5 patients (4 in combination with embolization). Symptom resolution and symptom control were achieved in 69% and 31% of patients, respectively, in the entire cohort. A radiographic cure was demonstrated in 50% of patients. There were no statistical differences in clinical outcomes or radiographic cure rates between patients treated with different modalities.

CONCLUSIONS

Head and neck AVMs can be treated successfully with a primarily endovascular management strategy by a multidisciplinary team with the goal of symptomatic control.

Surgical management of auricular arteriovenous malformations: A literature review

Auricular arteriovenous malformations (AVMs) can cause a variety of symptoms that seriously impact the patient's appearance, life, and mental well‐being. Surgery is the primary management method for auricular AVMs, but there is no consensus on how to surgically manage auricular AVMs. In this article, we document a comprehensive review of the characteristics, classification, and surgical interventions to treat auricular AVMs.

Injectable Hydrogel Capable of In Situ Covalent Crosslinking for Permanent Embolization

Vascular embolization provides an effective approach for the treatment of hemorrhage, aneurysms, and other vascular abnormalities. However, current embolic materials, such as metallic coils and liquid embolic agents, are limited by their inability to provide safe, consistent, and controlled embolization. Here, we report an injectable hydrogel that can remain at the injection site and subsequently undergo in situ covalent crosslinking, leading to the formation of a dual-crosslinking network (DCN) hydrogel for endovascular embolization. The DCN hydrogel is simple to prepare, easy to deploy via needles and catheters, and mechanically stable at the target injection site, thereby avoiding embolization of nontarget vessels. It possesses efficient hemostatic activity and good biocompatibility. The DCN hydrogel is also clearly visible under X-ray imaging, thereby allowing for targeted embolization. In vivo tests in a rabbit artery model demonstrates that the DCN hydrogel is effective in achieving immediate embolization of the target artery with long-term occlusion by inducing luminal fibrosis. Collectively, the DCN hydrogel provides a viable, biocompatible, and cost-effective alternative to existing embolic materials with clinical translation potential for endovascular embolization.

A Case of Scalp Arteriovenous Malformation Treated by Transvenous Embolization Using Onyx

Objective

We treated a case of scalp arteriovenous malformation (sAVM) by transvenous embolization using Onyx.

Case Presentation

We describe the case of a 17-year-old woman with a pulsatile mass at the right temporal area. DSA identified sAVM with the venous pouch between the right occipital artery (OA) and the right two occipital veins (OVs), which was also fed by multiple branches of the right posterior auricular artery (PAA) and superficial temporal artery (STA). The shunts were completely occluded by the reverse pressure cooker technique (RPCT), which involves navigating the balloon catheters just distal to the shunt point in the OVs approaching from the right external jugular vein (EJV) and injecting Onyx to each feeder retrogradely with balloons inflated.

Conclusion

This technique may be useful for treating sAVM with venous angioarchitecture enabling a transvenous approach.

The usefulness of temporary balloon occlusion during transarterial embolization for scalp arteriovenous fistula

Background:

We present two cases of scalp arteriovenous fistula (sAVF) treated by transarterial embolization with the aid of a temporary balloon occlusion (TBO) to detect precise vasculature.

Case Description:

Case 1: A 59-year-old woman noticed a sudden onset of pulsating bruits. sAVF was fed by the right superficial temporal artery (STA) and drained to the right superficial temporal vein. We performed feeder occlusion using coils after the recognition of a single feeder and a single fistula using TBO. Case 2: A 42-year-old woman noticed a pulsating subcutaneous mass. sAVF was fed by the right occipital artery (OA) and drained to the right occipital vein (OV). We could detect another feeder of the right STA after the TBO of the OA. We performed transarterial feeder occlusion for STA and OA using coil and N-butyl-2-cyanoacrylat including OV and shunt point, because this case was a single fistula with multiple feeders.

Conclusion:

sAVFs are a relatively rare disease with a complex vascular structure. For the adequate transarterial approach, TBO was useful for detecting the precise vasculature of sAVF.

The use of dual-lumen balloon for embolization of peripheral arteriovenous malformations

PURPOSE

We aimed to evaluate the safety and feasibility of the embolization of peripheral arteriovenous malformation (AVM) with non-adhesive liquid agents (NALA) injected by dual-lumen balloons (DLB).

METHODS

We conducted a multicenter retrospective study between January 2017 and June 2019, including patients with peripheral AVM embolized with NALA by DLB. Fourteen patients were included. The AVM classification, technical and clinical success were evaluated, as were nidus size, liquid agent used, volume and time of injection in DLB, complications, follow-up and need of surgical intervention.

RESULTS

The mean age of the patients was 37±22.5 years (range, 6-82 years). The mean nidus size was 5.2±2.4 cm (range, 3.0-12.0 cm). By Schobinger classification, 11 AVMs were classified in stage 3 and 3 AVMs were classified in stage 2. By Cho's classification, 2 AVMs were in stage II, 4 AVMs were in stage I, 4 AVMs were in stage IIIa and 4 AVMs were in stage IIIb. Onyx was used in 11 patients (78.6%), while Squid, PHIL, and both Onyx and Squid were used in one patient each (7.1%). Seven patients (50%) required one session of embolization, 4 patients (28.6%) required two, 2 patients (14.3%) required three and 1 patient (7.1%) required four sessions. Complete nidus exclusion was achieved in 11 patients (78.6%), optimal clinical response in 12 patients (85.7%). Four patients (28.6%) exhibited minor complications, all controlled. No major complications were seen. Four patients underwent surgical intervention (28.6%).

CONCLUSION

The embolization of peripheral AVM with NALA in DLB appears to be safe and feasible, achieving high rates of technical and clinical success.

Vascular anomalies: Classification and management

Vascular anomalies are broadly classified into two major categories: vascular tumors and vascular malformations. Most vascular anomalies are caused by sporadic mosaic gene mutations, and recent genetic studies have advanced our understanding of the molecular pathways involved in their pathogenesis. These findings have suggested new therapeutic approaches to vascular anomalies, focusing on their pathogenetic mechanism. This chapter seeks to integrate an improved molecular understanding within the updated classification system of the International Society for Study of Vascular Anomalies. We emphasize the genetic, radiologic, and interventional aspects of diagnosis and management in hopes of allowing improved multidisciplinary collaboration surrounding these complex and interesting anomalies.

High Flow Scalp Arteriovenous Malformation: A Case Report

Scalp arteriovenous malformations (AVMs) are abnormal vascular lesions, which can be managed effectively and safely with surgical or endovascular approaches. Here, we discuss a case of scalp AVM malformation in a 25-year-old female, in which due to the proximity of the feeder artery to right orbit, surgical excision was preferred and the AVM was excised with an uneventful post-op course.

Method for Safely Excising a Large Head and Neck Arteriovenous Malformation in the Hybrid Operating Room

Large head and neck arteriovenous malformations are notoriously difficult to manage given their location and propensity for extreme hemorrhage. We propose a unique approach utilizing a Hyperform balloon and percutaneous Surgiflo sclerotherapy to provide intraoperative hemostatic stability during the excision of a left-sided scalp arteriovenous malformation. In a hybrid operating room a microcatheter balloon was fed into the left external carotid artery for occlusion of the malformation's main blood supply, and subsequently followed with digital subtraction angiography guided sclerotherapy of selective vessels. A split thickness graft was used to reconstruct the site of excision. This method offered optimal hemostatic control with a blood loss less than 120 cc. Our approach may offer safety advantages over traditional modalities and allow resection of head and neck lesions previously thought to be inoperable.

Resection of a posterior fossa arteriovenous malformation complicated by leaked Onyx: a case report and review of literature

Extravasation of Onyx is a rare complication during embolization of arteriovenous malformations (AVM). We present a case of embolization that was complicated by leakage of Onyx into the cerebellum which was later encountered during surgical excision of the AVM. Our goal is to report this rare event and to outline successful treatment of this complication. The patient's records were reviewed for medical history, laboratory and radiologic workup, and outpatient clinical follow-up. A 62-year-old female presented with Hunt Hess grade 2 and modified Fisher grade 2 subarachnoid hemorrhage (SAH) secondary to ruptured left posterior inferior cerebellar artery (PICA) aneurysm associated with a superior cerebellar vermian AVM. Following endovascular intervention, the aneurysm was completely embolized; however, only 75% of the AVM could be safely obliterated. Extravasation of Onyx from the ruptured aneurysm was noted on her initial angiogram. Elective suboccipital craniectomy was subsequently planned for resection of the residual AVM where the extravasated Onyx posed an operative nuisance during resection. Post-op angiogram confirmed complete resection of the AVM, as well as the bulk of the extravasated Onyx. Patient did well post-operatively, remaining neurologically intact throughout her hospital course. Although infrequently reported in the literature, Onyx extravasation is a potential complication that neurosurgeons should be ready to face. Adherence of Onyx to surrounding parenchyma could hinder optimal surgical resection of AVM and increase complications. Therefore, careful surgical dissection should be performed with special care to delicate neurovasculature. In this case, complete resection of the AVM and Onyx mass was safely achieved.

Management of extracranial arteriovenous malformations of the head and neck

The purpose of this study was to review the outcomes of the different therapies for extracranial head and neck arteriovenous malformations (AVMs). AVMs are high-flow congenital vascular anomalies. They are composed of a complex system of vessels directly connecting feeding arteries to draining veins forming a nidus. They may be potentially life-threatening due to progressive symptoms and infiltrative disease. Extracranial AVMs most commonly affect the head and neck area (47.4%) followed by the extremities (28.5%). AVMs are best characterized as being either focal or diffuse. Focal AVMs have good outcomes following adequate treatment. Diffuse lesions have multiple feeding vessel, which results in high rates of recurrence despite treatment. The management of AVMs includes conventional surgery and endovascular techniques. A combination of embolization and surgical resection has become the treatment of choice over the last years. The main goal of both forms of treatment being the complete blockage or resection of the nidus. Transcatheter embolization of vessels has evolved over the years and new embolic agents have emerged. The types of materials available for embolization are classified into mechanical devices, liquid agents and particulates. Efficacy, rate of recurrence and most common complications were evaluated. AVMs recurrence after embolization or resection is reported in up to 80% of cases. Incomplete resection and embolization can induce aggressive growth of the remaining nidus and the risk of progression is up to 50% within the first 5 years and recurrences can occur up to 10 years later. Although ethanol seems to be associated with the highest degree of cure and permanent occlusion, the overall complication rate reported was 48%. Other materials, such as cyanoacrylate, have obtained modest rates of complete remission, while the reported rates of complete regression of AVMs with Fibrin glue and Polyvinyl alcohol are above 50%. At present, there are no unified agreement on the ideal embolic agent. Therefore, a multidisciplinary approach is recommended to support decision making about the best therapeutic approach and to achieve optimal outcome. A long-term post-treatment follow-up is recommended to recognize early recurrence.

Current status of endovascular treatment for dural arteriovenous fistula of the transverse-sigmoid sinus: A literature review

Most intracranial dural arteriovenous fistulae (DAVFs) involve the transverse-sigmoid sinus (TSS), and various types of endovascular treatment (EVT) have been involved in managing TSS DAVFs. A current, comprehensive review of the EVT of TSS DAVFs is lacking. This study used the PubMed database to perform a literature review on TSS DAVFs to increase the current understanding of this condition. For high-grade TSS DAVFs such as Borden type 3, the goal of EVT is curative treatment. However, for low-grade TSS DAVFs such as Borden type 1 and some Borden type 2 TSS DAVFs, symptom relief or elimination of cortical reflux may be sufficient. Currently, EVT has become the first-line treatment for TSS DAVFs, including transarterial embolization (TAE), transvenous embolization (TVE) or both. TAE alone and TSS balloon-assisted TAE are also commonly used. However, TVE for TSS DAVFs is recognized as the most effective treatment, including coil direct packing TSS, Onyx® (ethylene vinyl alcohol copolymer) TVE, and balloon-assisted Onyx® TVE, which are commonly applied. In addition, TSS reconstructive treatment can be an effective procedure to treat TSS DAVFs. EVT is accompanied with complications, including technique- and treatment-related complications. Although complications may occur, TSS DAVFs have an acceptable prognosis after EVT.

Results of Endovascular-First Approach for Treatment of Scalp Arteriovenous Malformations and the Effect of Simplified Angiographic Classification in Therapeutic Decision-Making and Outcomes

BACKGROUND

Scalp arteriovenous malformation (SAVM) is primarily treated by surgery and reports on endovascular treatment are scarce. We report the results of an endovascular-first approach in the treatment of SAVM. We also have proposed a simple dichotomized classification using the angiographically determined morphology findings and discussed its effect on therapeutic decision-making and outcomes.

METHODS

A consecutive series of 25 patients with SAVM treated by initial or endovascular-only methods were included in the final analysis. The SAVM was categorized as a plexiform or fistulous type according to the angiographic morphology. The demographic data, treatment variables, and final clinical outcomes were analyzed and correlated with the proposed classification.

RESULTS

Of the 25 patients, 21 were treated with n-butyl cyanoacrylate (n-BCA) and 3 with liquid ethylene vinyl alcohol. One patient had been treated initially with polyvinyl alcohol particles and later with n-BCA. Overall, complete or near complete obliteration (>90%) was achieved in 72%. Surgical excision was performed in 76%, most often after n-BCA embolization. Fistulous-type SAVMs required greater n-BCA concentrations (median, 33% vs. 20%; P = 0.024) and achieved greater rates of complete or near-complete obliteration (90% vs. 63%). Two patients with fistulous-type SAVMs treated with liquid ethylene vinyl alcohol showed complete resolution, and further treatment was not necessary. Overall, regardless of the embolic material used, the fistulous type demonstrated a significantly greater rate of complete obliteration (75% vs. 33%; P = 0.041) compared with plexiform type.

CONCLUSION

High rates of complete and durable obliteration of SAVM are achievable with endovascular embolization. The proposed simplified classification is easy to implement and can aid in choosing the appropriate embolic agent and predicting the therapeutic outcome.

Delayed migration of Squid 18 following embolisation of a direct carotico-cavernous fistula

We report a case of delayed migration of Squid 18 following treatment of a direct carotico-cavernous fistula.

Unilateral Hard Palate Necrosis After Ascending Palatine Artery Embolization

Embolization is a common treatment modality for refractory epistaxis. Here, the authors reported that the first patient with unilateral necrosis of the mucosa overlying the hard palate developed after embolization of ascending palatine artery. A 46-year-old man with a history of maxillofacial trauma complicated by 2 episodes of significant unilateral epistaxis. Although he did not experience any epistaxis after embolization, unilateral necrosis of the mucosa overlying the hard palate developed gradually 2 weeks after embolization. The necrotic tissue of hard palate was treated by surgical debridement and followed by antibiotic and analgesic.

Embolization of a superior sagittal sinus dural arteriovenous fistula under intrasinus balloon protection: A case report

Endovascular embolization has evolved to become the primary therapeutic option for dural arteriovenous fistulas (DAVFs). While guaranteeing complete occlusion of the fistula orifice, the goal of DAVF embolization is also to ensure the patency of normal cerebral venous drainage. This paper describes a case of successful embolization of a complex DAVF in the superior sagittal sinus with a multistaged approach using a combination of transvenous and transarterial tactics. The strategies and techniques are discussed.

Embolization of palpebral and orbito-frontal fistulas: technical and anatomical considerations in treating high-flow superficial skin lesions with liquid embolics

The treatment of palpebral and periorbital fistulas may be challenging due to the presence of multiple anastomosis with eloquent ophthalmic and intracranial vascular territories. Moreover, cosmetic and functional characteristics of this area pose unique challenges to open surgical approaches and endovascular therapy. We review the advantages and disadvantages of different liquid embolics in treating palpebral and periorbital fistulas as we describe three successfully treated cases. Moreover, we describe important anatomical landmarks that should be considered at the time of treatment of these lesions.

Preliminary experience with precipitating hydrophobic injectable liquid in brain arteriovenous malformations

Advancement in microcatheter design and emergence of new embolic agents offer better results in endovascular treatment of brain arteriovenous malformations (AVMs). Precipitating hydrophobic injectable liquid (PHIL) (Microvention) is a newly introduced dimethyl sulfoxide-based embolic agent for endovascular use. Herein, we present three patients who underwent endovascular treatment of brain AVMs with PHIL, followed by surgical resection. Endovascular features and same-day surgical handling of the new embolic agent PHIL are presented along with histopathologic changes in the acute stage in brain AVMs are presented, and its major differences from Onyx. In our series, PHIL had moderate inflammatory reaction in the acute stage without any associated angionecrosis that is different than Onyx which cause mild inflammatory reaction with angionecrosis. Smallest vessel containing PHIL was 2.9 μm compared to 5 μm with Onyx, which suggests better penetration.

Absence of skin discoloration after transarterial embolization of a subcutaneous auricular arteriovenous malformation with PHIL

BACKGROUND AND OBJECTIVE

One of the treatment options for arteriovenous malformations consists of embolization, with a choice of various embolic agents, with or without subsequent surgical excision. If embolization is offered without subsequent surgery, the embolic material will stay in situ, in which case the consistency and color become important in superficial lesions. The purpose of this case report is to describe if the use of a novel liquid embolic agent (PHIL) is well suited for treatment of superficial AVMs without subsequent surgery.

CASE DESCRIPTION

A 30-year-old male presented with a painful reddish, pulsatile swelling of the left ear that had been present for more than 10 years. Angiography confirmed an arteriovenous malformation supplied by the superficial temporal artery and the posterior auricular artery. The lesion was successfully treated by embolization with PHIL, through the superficial temporal artery. A minute residual shunt, from the posterior auricular artery, was accepted. Immediate disappearance of pulsatile tinnitus was reported. Moreover, return of normal skin color was observed without discomfort from the embolic deposits. This result has been stable throughout one year of clinical follow-up.

CONCLUSION

To our knowledge, this is the first case report describing PHIL embolization as a treatment option for superficial arteriovenous malformations without the necessity for subsequent surgery. The white color and rubbery consistency are beneficial characteristics of PHIL in treatment of subcutaneous lesions, especially in cosmetically relevant locations.

Interventional management of high-flow craniofacial vascular malformations: a database analysis and review of the literature

Background

High-flow craniofacial vascular malformations are uncommon, locally aggressive lesions that pose a therapeutic challenge.

Objective

To report our experience with the treatment of high-flow craniofacial vascular malformations.

Methods

After institutional review board approval was obtained, the neurointerventional databases of two institutions were retrospectively reviewed for vascular malformations from October 2010 to June 2015. All patients who had been treated for a high-flow craniofacial vascular malformation were included in the analysis. Clinical presentation, location, type, agent and techniques used, procedural complications, and clinical and imaging follow-up were included in the analysis.

Results

Eighteen patients (12 female and 6 male) harboring 21 high-flow vascular malformations met the inclusion criteria in our study. All patients were symptomatic. One patient had two separated arteriovenous malformations (AVMs) (one nasal and the other forehead/scalp), and one patient had three separated scalp lesions. One patient with a nasal AVM had capillary malformation-AVM syndrome. Overall, 13 AVM and 8 arteriovenous fistuli were treated in 31 targeted embolization procedures (ranging from 1 procedure to 4 procedures, mean 1.7 procedures). Onyx was the predominant agent used in 25 procedures. In 31 procedures, 1 procedural complication (skin ulceration) occurred. At the end of the last treatment session 14 of the 21 lesions were cured. Symptomatic control was achieved in all cases, with resolution or significant improvement of the symptoms (mean follow-up of 10 months).

Conclusions

High-flow craniofacial vascular malformations can be successfully managed with interventional techniques.

Occurrence and Management Strategies for Catheter Entrapment with Onyx Liquid Embolization

In June 2012, Food and Drug Administration (FDA) issued a warning about the risk of catheter entrapment associated with Onyx embolization. We used our experience, literature review, and FDA Manufacturer and User Facility Device Experience (MAUDE) data review to identify five strategies to address catheter entrapment: 1/. Surgical resection of vessel at point of entrapment of catheter and retraction from exterior portion at the femoral region; 2/. Advancing and closing the loop of snare over the entrapped catheter followed by retraction; 3/. Advancing the distal access catheter over the entrapped catheter and retraction with forward movement of the distal access catheters; 4/. Inflation of balloon catheter coaxial to the entrapped catheter with subsequent retraction; and 5/. Intravascular retention and internalization of microcatheter. In the MAUDE data, there were 77 reports of catheter entrapment with Onyx embolization; microcatheter was retracted by surgical excision in 15, endovascular snare or other retriever devices in 5, deliberately entrapped inside the vessel using stent in 1, and left without intervention within intravascular compartment in 27 patients.

Use of ethylene-vinyl alcohol copolymer as a liquid embolic agent to treat a peripheral arteriovenous malformation in a dog

CASE DESCRIPTION

An 11-year-old castrated male Tibetan Mastiff was evaluated because of a visibly enlarged blood vessel and progressively worsening swelling of the right hind limb.

CLINICAL FINDINGS

On physical examination, the right hind limb was markedly larger than the left hind limb and the dog was minimally weight bearing on the affected limb. A bruit was auscultated over the affected region. Ultrasonography of the tarsal region of the right hind limb revealed an artery with turbulent flow that communicated with venous drainage. A CT scan confirmed the presence of an arteriovenous malformation (AVM).

TREATMENT AND OUTCOME

Embolization of the AVM with a liquid embolic agent (ethylene-vinyl alcohol copolymer dissolved in dimethyl sulfoxide) was elected. An arteriogram was performed prior to treatment and delineated the vessels that were targeted for embolization. The embolic agent was infused into the AVM, and a postinjection arteriogram confirmed complete occlusion of the AVM nidus and normal arterial flow to the paw with subsequent normal venous drainage. The circumference of the abnormal paw was 51 cm before the procedure and 22.9 cm at 4 weeks after the procedure. Additionally, the gait of the dog dramatically improved. No complications associated with the procedure developed.

CLINICAL RELEVANCE

Peripheral AVMs in dogs are uncommon, and described treatment options are limited and generally associated with serious morbidity. A liquid embolic agent, ethylene-vinyl alcohol copolymer dissolved in dimethyl sulfoxide, was successfully administered in this case, and no morbidity was observed secondary to the procedure. Clinical success was characterized by substantial improvement in limb swelling and marked improvement in the gait of the dog.

Ethylene vinyl alcohol copolymer (Onyx®) in peripheral interventional radiology: indications, advantages and limitations

Onyx(®) is a remarkable liquid embolizing agent that may allow a well-trained operator to undertake challenging embolization procedures. In multiple interventional radiology indications, the physico-chemical properties of Onyx(®) allow safe embolization. The purpose of this article is to review the advantages and disadvantages of Onyx(®) and identify its main indications.

Concomitant transarterial and transvenous embolization of a pelvic arteriovenous malformation using a new liquid embolic agent, squid-12 and detachable coils

We describe a complex congenital pelvic AVM with multiple feeding arteries arising from the side branches of the right internal iliac artery and a single draining vein in a male patient. Concomitant transarterial and transvenous embolization with a new liquid embolic agent Squid-12 and metallic coils enabled a complete embolization at a single session. Squid-12 is composed of ethylene vinyl alcohol copolymers and its lower viscosity makes it a promising agent for the treatment of AVMs. The patient showed prompt resolution of the symptoms and complete devascularization of the AVM lesion was persisted on the 1-month control angiography. The patient was asymptomatic on the 6th month follow-up.

Endovascular balloon-assisted embolization of intracranial and cervical arteriovenous malformations using dual-lumen coaxial balloon microcatheters and Onyx: initial experience

BACKGROUND

Ethylene vinyl alcohol copolymer (Onyx) is widely used for the embolization of arteriovenous malformations (AVMs) of the brain, head, and neck. Balloon-assisted Onyx embolization may provide additional unique advantages in the treatment of AVMs in comparison with traditional catheter-based techniques.

OBJECTIVE

To report our initial experience in performing balloon-assisted AVM embolization for brain and neck AVMs with the use of the new Scepter-C and Scepter-XC coaxial dual-lumen balloon microcatheters.

METHODS

Balloon-assisted transarterial embolization was performed in a series of 7 patients with AVMs (4 with brain AVMs, 1 with a dural arteriovenous fistula, and 2 with neck AVMs) by using Onyx delivered through the lumen of Scepter-C or Scepter XC coaxial balloon microcatheters. Following the initial balloon-catheter navigation into a feeding artery and the subsequent inflation of the balloon, the embolization was performed by using Onyx 18, Onyx 34, or both.

RESULTS

A total of 12 embolization sessions were performed via 17 arterial feeders in these 7 patients. In 1 patient, there was an arterial perforation from the inflation of the balloon; in all others, the embolization goals were successfully achieved with no adverse events.

CONCLUSION

The balloon microcatheters showed excellent navigability, and there were no problems with retrieval or with the repeated inflation and deflation of the balloons. A proximal Onyx plug, which is crucial in many AVM embolizations, was not necessary with this technique. Additionally, fluoroscopy and procedural times seemed lower with this technique compared with conventional embolization methods.

Facial necrosis after endovascular Onyx-18 embolization for epistaxis

Background:

Evolution in techniques and equipment has expanded the role, effectiveness, and safety of endovascular transarterial embolization for the treatment of severe epistaxis. Risks from this treatment approach include major ischemic complications. To date, there have been only a few reports of soft tissue necrosis following endovascular embolization for severe epistaxis; none involve the use of Onyx-18.

Case Description:

We report the case of a 52-year-old woman who presented with epistaxis that was refractory to medical and surgical management, which lead to endovascular intervention and embolization with Onyx-18. The patient subsequently developed nasal ala and facial necrosis as a result of the procedure.

Conclusion:

We report the use of Onyx-18 for the endovascular embolization of a patient with severe epistaxis and subsequent complications. In cases of severe epistaxis that warrant intervention in the form of embolization, ischemic complications are rare; however, ischemic complications may be unavoidable and should factor into the discussion regarding procedural risks.

Treatment of dural arteriovenous fistula by balloon-assisted transarterial embolization with Onyx

OBJECTIVE

This study evaluated the feasibility, safety, and efficacy of embolization of dural arteriovenous fistula via a very small, short feeding artery with the assistance of a balloon placed proximal to the tip of the microcatheter, such that the balloon serves as a plug.

METHODS

Eight patients who underwent treatment of DAVF by balloon-assisted transarterial embolization with Onyx were retrospectively reviewed. Gender, age, angiography findings, procedure details, clinical and angiographic outcomes, complications, and follow-up were recorded and analyzed.

RESULTS

Nine embolization procedures were performed in eight male patients via extracranial arteries. Balloon-assisted embolization was successful in all eight patients. A Hyperglide balloon was used in five patients, and a Hyperform balloon was used in three patients. Angiographic resolution of the fistula was achieved in all patients without complications. All patients recovered uneventfully. During the follow-up period of 7-19 months, all patients were asymptomatic except for one patient who experienced mild headaches.

CONCLUSIONS

Treatment of DAVF by balloon-assisted embolization with Onyx achieved promising results, even in patients with very small and short feeding arteries. This technique allowed the treatment of DAVF cases where other techniques have failed.

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.