New Treatment Approaches to Arteriovenous Malformations

Complex management of concurrent lower extremity arteriovenous malformations: A case study and review of interventional techniques

Arteriovenous malformations (AVMs) are rare vascular anomalies that present complex diagnostic and therapeutic challenges, particularly in uncommon locations such as the lower extremities. A 72-year-old female with chronic atrial fibrillation, hypertension, and peripheral vascular disease presented with severe lower extremity edema due to multiple AVMs below the knee. This case underscores the importance of a multidisciplinary, individualized approach in managing complex AVMs and highlights the need for advanced imaging and diverse interventional techniques to ensure effective treatment and long-term outcomes.

Pseudoaneurysm formation after embolization of giant arteriovenous malformation of the lower limb associated with Parkes Weber syndrome: A case report and literature review

A 63-year-old woman presented with a giant arteriovenous malformation (AVM) of the lower limbs associated with Parkes Weber syndrome (PWS). The AVM was supplied by 4 branches of the right profunda femoris artery and 4-stage embolization was performed. At 67 years of age, she developed a pseudoaneurysm due to the recanalization of a coiled profunda femoris artery branch arterial aneurysm. We performed re-embolization of the coiled profunda femoris artery and observed its shrinkage, but 2 months later, the pseudoaneurysm began to expand again, having a fatal course. This case indicates that battles against giant AVM-associated PWS follow a long and convoluted path. We present this case with reviewing 15 previously reported cases to improve our management of PWS.

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.

Head and Neck Vascular Anomalies in Children

Craniomaxillofacial vascular anomalies encompass a diverse and complex set of pathologies that may have a profound impact on pediatric patients. They are subdivided into vascular tumors and vascular malformations depending on biological properties, clinical course, and distribution patterns. Given the complexity and potential for leading to significant functional morbidity and esthetic concerns, a multidisciplinary approach is generally necessary to optimize patient outcomes. This article reviews the etiology, clinical course, diagnosis, and current management practices related to vascular anomalies in the head and neck.

New Insights into Cervicofacial Vascular Anomalies

Congenital cervicofacial vascular anomalies are extremely rare and present many difficulties in diagnosis and treatment requiring a multidisciplinary approach. Firstly, there is little consensus on this subject among head and neck specialists. There are two main types of vascular anomalies: vascular tumors and vascular malformations. Vascular malformations are also divided into malformations with slow blood flow (veins, lymphatics, capillaries or combined) and malformations with a fast blood flow (arteriovenous malformations and fistula). Vascular tumors like hemangiomas are known for their spontaneous involution with aging, while vascular malformations grow in dimensions with age. It is very important to choose the correct differential diagnosis between cervicofacial hemangiomas and vascular malformations for proper therapy management. Anamnesis and clinical exams help in raising suspicions about the real nature of a cervico-vascular anomaly. Furthermore, imaging brings in-depth details of the anomaly, ranging from ultrasound and contrast CT to MRI scanning and minimally invasive angiography. Angiography with selective embolization is rarely a curative procedure for arteriovenous malformations, being more suitable as a preliminary step before attempted surgical removal. Surgery is clearly necessary when there are aesthetic and functional deficits. Slow-flow vascular malformations present a reduced morbidity, and in cases without involution, the surgical ablation is reserved for the cases with aesthetic dysfunctions or psychological trauma. Lymphatic malformations must undergo surgical ablation when they are associated with mass effects and compression of great vessels or aerial viscera. The prognosis after surgical removal is good, with a low rate of recurrence or morbidity. Fast-flow vascular malformations require a combined approach, with embolization and excision in the next 48 h for safety reasons. Removal may be followed by reconstructive surgery depending on the location and dimensions of the malformation, with a possible secondary recovery of the normal microscopic vessels. Some of the masses may hinder the normal airflow and swallowing. Pathology is the gold standard for confirming the clinical and imaging diagnosis.

Congenital Vascular Malformations in Children: From Historical Perspective to a Multidisciplinary Approach in the Modern Era-A Comprehensive Review

Congenital vascular malformations (CVMs) are the result of an aberrant development during embryogenesis. Although these lesions are present at birth, they are not always visible yet. Once symptomatic, patients suffer from pain, bleeding, ulcers, infections or lymphatic leakage, depending on the subtype of vessels involved. Treatment includes conservative management, surgery, sclerotherapy, embolization and pharmacological therapy. The clinical presentation varies widely and treatment can be challenging due to the rarity of the disease and potential difficulties of treatment. This review gives an overview of the historical developments in diagnosis and classification and exposes the key elements of innovations in the past decades on the identification of genetic mutations and personalized treatment. These advances in the field and a multidisciplinary approach are highly valuable in the optimization of clinical care aimed at both curing or stabilizing the CVM and pursuing physical and psychosocial wellbeing.

Surgical Treatment of Multiple Venous and Arterial Aneurysms Due to Arteriovenous Malformations of the Arm

Introduction

Arteriovenous malformations (AVMs) are rare, especially in elderly patients. Occasionally, AVM can produce aneurysmal degenerations, which can lead to bleeding or rupture. The aim of this case report was to describe the surgical treatment of large arterial and venous aneurysms in the arm associated with an AVM.

Report

An 83 year old woman of White ethnicity who was a non-smoker presented with a large pulsatile aneurysm at the left elbow with paresis of the first three fingers. The diagnosis was made by duplex ultrasonography (DUS), computed tomography angiography (CTA), and arteriography. Additional tests confirmed aneurysms of the brachial artery and the outflow veins, with the largest more than 7 cm in diameter. A very proximal brachial artery bifurcation and increased venous flow were noted. DUS confirmed the AVM by showing continuous flow in the axillary vein. The decision for surgical resection involved vascular surgeons, radiologists, angiologists, and anaesthetists. Treatment involved opening and excision of multiple venous aneurysms and AVMs. A short segment of the aneurysmal brachial artery was also resected and repaired with end to end anastomosis. The deep brachial artery which supplied AVMs and venous aneurysms was ligated and excision of these lesions was performed. At one year follow up, there were no complications and the revascularisation was patent.

Discussion

Arterial and venous aneurysms occurring together with AVMs are rare and not well documented in the medical literature. In this case, surgical intervention, including resection with direct anastomosis of the arterial aneurysm coupled with excision of venous aneurysms and AVM, proved to be effective, as evidenced by stable post-operative outcomes after one year.

Application of epinephrine mixed with local anaesthetics in injection sclerotherapy of early-stage arteriovenous malformation

PURPOSE

To explore the effect of epinephrine mixed with local anaesthetic injection on blood flow control in early stage arteriovenous malformation (AVM) and explore suitable cases.

METHODS

Twenty-five patients with early stage (Schobinger clinical stage I/II) AVM were selected between September 2019 and March 2022. Local anaesthetics containing epinephrine were injected around the nourishing artery and into lesions under the guidance of ultrasound, and the blood flow distribution grade in the lesions as well as the changes in diameter, peak systolic velocity (PSV), and resistance index (RI) of the nourishing arteries and vessels in the lesions were observed to determine the type of AVM suitable for epinephrine injection. After blood flow was controlled, sclerosant agents were injected into the lesions for sclerotherapy.

RESULTS

After local injection of the epinephrine mixture, the blood flow distribution in the lesion decreased by one to three grades; the diameter and PSV also decreased, while RI increased. There were statistically significant differences before and after the injection (P < 0.05). The efficacy of the injection was 80% (20/25), especially in patients with lesion vessels, a nourishing artery lumen diameter <2 mm, and a PSV <40 cm/s in the lesion. Patients with Schobinger clinical stage I AWM showed good results.

CONCLUSIONS

Local anaesthetics containing epinephrine play a positive role in reducing the distribution and velocity of blood flow in patients with AVM lesions and may be used as an experimental method for the treatment of AVM, which is beneficial for sclerotherapy in patients with early AVM.

Dye Laser to Treat an Arteriovenous Malformation of the Tongue: 40-Month Follow-Up

Arteriovenous malformations (AVMs) are abnormal connections between blood vessels that bypass the normal capillary bed. To avoid the invasiveness of the gold standard surgical excision, the use of dye laser has been suggested as an alternative. A 53-year-old man in good overall health presented with a large bluish-red nodular growth covered by intact mucosa on the left side of his tongue. The growth had a hard-elastic consistency and was not painful to touch. Imaging investigations revealed a capsulated growth consistent with a diagnosis of AVM. The patient underwent two sessions of rhodamine dye laser treatment using the following parameters: fluence of 12 J/cm2, 6 mm laser spot, a single pulse with repetition up to 1.0 Hz, and a pulse duration of 3.0 ms. Follow-up examinations were conducted at 12, 24, 36, and 40 months after the treatment. At the 40-month follow-up, the lesion had reduced in size, with a more organized vascular network, and was not clinically detectable. Considering the limitations of this case report, the application of dye laser appears to be a potentially successful treatment option for AVMs.

Early experience of thalidomide therapy for high-grade peripheral and facial arteriovenous malformations

BACKGROUND

Arteriovenous malformations (AVMs) are developmental defects in the vascular system with abnormal connections between arteries and veins. A minority of AVMs are characterized by aggressive growth and continue to proliferate despite maximal surgical and interventional therapy. We report our outcomes with the use of thalidomide as the only UK specialist center adopting this novel approach for the management of AVMs refractory to conventional therapy.

METHODS

This was a retrospective case series which included only complex and proliferative AVM lesions (Schobinger grade III and IV). All patients prescribed thalidomide on a compassionate basis between September 2006 and August 2022 after attempts at embolosclerotherapy without satisfactory response were reviewed.

RESULTS

Eleven patients were included in our study. The median total duration of thalidomide use was 10 months. Two thirds of patients with pain (six of nine) reported an improvement, three quarters reported a reduction in swelling (six of eight) and all who presented with bleeding reported improvement in overall volume or frequency (four of four). Over the study period, 45% achieved a non-proliferative state with no further target vessel demonstrable on angiography. Mild, tolerable side effects such as fatigue were common (73%). There was only one major adverse reaction (neutropenia) necessitating cessation of therapy.

CONCLUSIONS

We can conclude that thalidomide is able to reduce the symptom burden for patients with complex and proliferative AVMs that were refractory to established treatment modalities. Adverse effects are common, but the benefit achieved from taking thalidomide in otherwise treatment resistant cases outweighs the risks, most of which are manageable.

Angiographic Types of Palpebral Arteriovenous Malformations and Relevant Therapeutic Options Based on Ethanol Embolization: A Multicenter Study

PURPOSE

The present work aimed to determine the different angio-architectural types of palpebral arteriovenous malformations (pAVMs) and appropriate ethanol embolotherapy for each type.

MATERIALS AND METHODS

This was a multi-center comparative effectiveness research retrospectively conducted from November 2012 to October 2021. A total of 70 patients with pAVMs were included, which was classified into cystic pAVMs (n=29) and diffuse pAVMs (n=41) based on the angio-architecture. Of the included patients, 17 with cystic pAVMs and 13 with diffuse pAVMs underwent ethanol embolization combined with coils (CE). The remaining participants underwent no-coil ethanol embolization (NCE). Participants had undergone 60 months of follow-up. Normality of data was tested by the D'Agostino and Pearson test. Correlation was tested by the Pearson χ2 test. Deterioration-free survival (DFS) rate was estimated using the Kaplan-Meier survival analysis. Multivariate Cox regression models included variables that were significant at a p value<0.05 in the univariate analysis to screen the prognostic factor.

RESULTS

The local symptoms of pAVMs, including pulsation, warmth, red plaque, blepharoptosis, bleeding, and visual blurring, along with the devascularizational grade of angiography were recorded before and after the respective procedures. Post-treatment complications were either evaluated at the 3-month routine follow-up or were self-reported by patients. Cystic pAVMs presented with significantly different clinical and angiographic features compared with diffuse pAVMs. With CE, patients with cystic pAVMs obtained a higher devascularizational grade (p<0.0001) and better clinical outcomes (p=0.0009) than those with diffuse pAVMs. Contrarily, with NCE, patients with diffuse pAVM had better outcomes than those with cystic pAVMs (p=0.0248). Moreover, the overall DFS rate was higher in patients with cystic pAVMs (p=0.0006). Finally, the angio-architecture of pAVMs was found to independently influence its prognosis (p=0.02).

CONCLUSIONS

In pAVMs, the angio-architectural type was associated with the relative prognostic status. Ethanol embolization combined with coils was an effective method to treat cystic pAVMs, whereas NCE was more suitable for the diffuse type, further emphasizing the importance of a type-based therapeutic strategy for pAVMs.

CLINICAL IMPACT

Palpebral arteriovenous malformations (pAVMs) are rare and tricky in clinical practices. The present study has divided the pAVMs into cystic and diffuse types according to their angiographic characteristics. Ethanol embolization with (CE) or without coils (NCE) was performed on both types. CE was suitable for cystic pAVMs; whereas NCE was a better choice for diffuse pAVMs. The five-year survival analyses provided evidence of the safety and efficacy of ethanol application in pAVMs. Finally, our work demonstrated that both the short- and long-term clinical outcomes of diffuse pAVMs were poor compared to those of cystic pAVM.

Management of scalp arteriovenous malformations: a rising trend towards percutaneous direct puncture embolization technique-our experience

BACKGROUND

Scalp arteriovenous malformations (AVMs), or cirsoid aneurysms of the scalp, usually present with troublesome symptoms and cosmetic disfigurement. Endovascular/percutaneous embolization has evolved as a sole treatment method or adjunct to surgical excision in the management of scalp AVMs with an excellent outcome.

PURPOSE

To discuss minimally invasive techniques for treating scalp AVMs as well as to highlight the role of embolization before surgery.

MATERIAL AND METHODS

This is a retrospective study of 50 patients with scalp AVM who underwent embolization (percutaneous/endovascular) during 2010-2019 at a tertiary care center. n-butyl cyanoacrylate (n-BCA) was used as an embolizing agent in all the cases and the patients were followed up at three- and six-month intervals with Doppler evaluation.

RESULTS

A total of 50 patients were included in the study. The occipital region was the most common location; 82% were Schobinger class II lesions and 18% were class III lesions. Thirteen patients had small-sized AVMs and 37 patients had large-sized AVMs. Post-embolization surgery was performed in 36 patients. Of the patients, 28 underwent percutaneous embolization, 20 underwent endovascular embolization, and two underwent both to achieve complete embolization of the lesion. The number of percutaneous procedures increased in the latter half of the study period as the safety and efficacy of the technique were established. No major complications were seen in this study.

CONCLUSION

Embolization of scalp AVMs is a safe and effective technique and can be used in isolation for small lesions and as an adjunct procedure to surgery for large-sized lesions.

Lower-Extremity Arteriovenous Malformation Masquerading as Peripheral Artery Disease

An arteriovenous malformation (AVM) refers to an anomalous, direct connection between an artery and a vein. Typically, these two vessels are interposed by high-resistance capillary beds, the absence of which results in a high-flow system from an artery into a vein. Venous vessel walls are not designed to handle such high-pressure blood flow, and their vessel wall structure becomes permanently altered and weakened. For this reason, AVMs are at an increased risk for hemorrhages and ruptures. AVMs present with a spectrum of symptoms, ranging from skin discoloration, ischemia in distal tissues, and heart failure from arteriovenous shunting. Here, we present a case of a patient who underwent amputation of his second left toe, initially thought to be a result of peripheral arterial disease (PAD) due to his extensive smoking history. Further imaging findings revealed a rare lower-extremity AVM as the source of his ischemia, not PAD. Ultimately, the treatment of the vascular anomaly and resolution of the patient's symptoms were achieved via transarterial embolization. This case emphasizes the importance of looking beyond PAD as the cause of distal lower-extremity ischemia and provides insights into an uncommon and often missed diagnosis of extracranial AVMs.

Unique Case of Parathyroid Adenoma With Arteriovenous Malformation

Direct communication between dysmorphic arteries and veins without an interceding capillary segment is known as arteriovenous malformation (AVM). Its etiology is still unknown; however, it is commonly acknowledged that it could be related to trauma or is congenital in origin. Often, AVMs are found in the central nervous system or other sites such as under the skin or in the deep solid organs. They can be encountered as a solitary abnormality or associated with another pathology. If they are large enough, they can deprive the neighboring tissue of oxygen, eventually leading to tissue damage and compressing the surrounding organs, causing potentially more serious consequences. AVM in parathyroid adenoma is an unusual entity in the medical reports and known clinical practice. We herein report a unique case of a 49-year-old female patient who presented with a neck mass and associated symptoms of hyperparathyroidism (HPT) with no history of previous trauma or surgery. The imaging and laboratory tests were consistent with parathyroid neoplasm. Parathyroidectomy was performed and revealed parathyroid adenoma with AVM.

A rare association of arteriovenous malformation of the omentum and pseudo-Meigs' syndrome: case report and scoping review of literature

Meigs' syndrome is defined as a secondary triad of ascites, pleural effusion and benign ovarian tumor, usually fibroma. While pseudo-Meigs' syndrome is a rare condition that is associated with benign ovarian tumor-other than fibroma-or even malignant. The case presented is a 40-year-old Saudi, nulliparous woman who was referred for precise diagnostic work-up as a case of huge pelvic-abdominal mass, tense ascites and pleural effusion. After further investigations cancer antigen-125 was found to be elevated. An abdominal CT scan revealed significant interval increase in the size of ascites, which cause huge abdominal distention, as well as a significant pleural effusion. Pathology of surgical specimens revealed a giant uterine leiomyoma, whereas the omentum excision surprisingly confirmed multiple disorganized arteries and veins, which resulted in omental arteriovenous malformation. To the best of our knowledge, this is the first reported case in the worldwide literature of two different rare conditions.

Management of high-output cardiac failure caused by head and neck AVMs: Percutaneous suture-assisted ethanol and coil embolotherapy

Purpose

The aim of this study was to describe the treatment technique, outcomes, and complications of Schobinger stage IV head and neck arteriovenous malformations (HNAVMs) with associated high-output cardiac failure (HOCF) using ethanol and coils with the percutaneous suture technique.

Methods

From January 2015 to December 2019, 19 patients who had HNAVMs with associated HOCF were treated first with a percutaneous suture of the remarkably dilated dominant drainage vein (RDDOV) and subsequent embolization with coils and ethanol. The percutaneous suture of RDDOV was preferred to be performed, followed by the deployment of coils and the injection of absolute ethanol via transarterial approach, direct puncture approach, or both of them. Treatment outcomes and complication rates were evaluated at follow-up.

Results

A total of 19 patients who experienced HNAVMs with HOCF received 19 percutaneous suture procedures and 84 embolization procedures with ethanol and coils. Complete or >90% shunt reduction of the AVM was achieved in 16 patients. Notably, 19 patients with New York Heart Association (NYHA) stage II improved to stage I, and the symptom of dyspnea disappeared after embolization. The symptoms of five patients with bleeding disappeared. All patients presented with cosmetic concerns; Four were cured, and eight had a clearly recognizable improvement. Of note, 19 (100%) patients presented with impairment of daily life, which was resolved. The minor complications were encountered and recovered by the self. No major complications occurred.

Conclusion

This study provides evidence that ethanol and coil embolotherapy is effective and safe in treating HOCF caused by HNAVMs with acceptable complications in these cases. The percutaneous suture technique for RDDOV management can act as an adjunct for embolotherapy.

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.

Vascular anomalies: clinical perspectives

Vascular anomalies are classified as vascular tumors or vascular malformations according to their cellular features and biological behavior. Detailed history and clinical assessment allow for the proper clinical diagnosis of most vascular anomalies and guide the choice of imaging to evaluate them. This article discusses the general information needed from a clinical history and physical exam to formulate a diagnosis of vascular anomaly. Then, the authors review the clinical findings from the most common vascular tumors and vascular malformations.

Vascular lesions of the pediatric orbit: A radiological walkthrough

Vascular anomalies of the pediatric orbit represent a heterogeneous group that include both vascular tumors and vascular malformations. The disorder may initially be silent and then associated with symptoms and/or function damage, depending on the type of vascular anomaly and its extension. Vascular tumors include benign, locally aggressive (or borderline) and malignant forms while vascular malformations are divided into "simple", "combined" and syndromic, or "low flow" or "high flow". Both entities can arise in isolation or as part of syndromes. In this review, we describe the imaging findings of the vascular lesions of the orbit in the pediatric population, which are key to obtain a correct diagnosis and to guide the appropriate treatment in the light of the new genetic and molecular discoveries, and the role of the radiologist in their multidisciplinary management. We will also touch upon the main syndromes associated with orbital vascular abnormalities.

Moorman A. Congenital systemic arteriovenous fistulas: Interventional strategies and embryological perspectives

Background:

Data on congenital systemic arteriovenous fistulas are largely based on individual case reports. A true systemic arteriovenous fistula needs to be differentiated from other vascular malformations like capillary or venous hemangiomas, which are far more common.

Objectives:

We sought to identify the varied symptoms, diagnostic challenges, describe interventional treatment options, and postulate an embryological basis for this uncommonly described entity.

Methods:

This is a descriptive study of a cohort of systemic arteriovenous fistulas seen in the department of pediatric cardiology at a tertiary cardiac institute from 2010 to 2020, with prospective medium-term follow-up. A total of seven cases were identified. The diagnosis was confirmed by computed tomographic imaging, magnetic resonance angiography, or conventional angiography.

Results:

All were successfully closed using duct occluders or embolization coils with no recurrence in six cases over a median duration of follow-up of 48 months (interquartile range: 16; 36–52 months). Four of the seven cases underwent follow-up imaging using echocardiography or ultrasound.

Conclusion:

The incidence of congenital systemic arteriovenous fistulas is low and accounted for 0.009% of pediatric outpatients seen over 10 years at our institute. The spectrum of clinical presentation varies from an innocuous swelling or a pulsating mass to frank heart failure. Strong clinical suspicion and advanced imaging modalities have helped identify some hitherto undescribed connections. Large malformations with multiple communications may persist or recur despite transcatheter closure.

Dominant outflow vein occlusion in the management of naturally occurring peripheral arteriovenous anomalies in cats and dogs

Two dogs and 1 cat were referred to a tertiary veterinary center for the consultation and treatment of limb edema, variable dermal sanguineous crusting lesions, and intermittent lameness. A peripheral arteriovenous anomaly (PAA) was diagnosed via computed tomographic angiography (CTA) in each case. Arteriography enabled further evaluation of the PAA with confirmation of a dominant outflow vein. Dominant outflow vein occlusion was achieved by direct ligation in 1 dog and retrograde transvenous glue embolization in the cat and other dog. Repeat arteriography demonstrated resolution of arteriovenous shunting. Presenting clinical signs resolved in all animals. The previously identified aberrant vessels in 1 dog were not identified after CTA 40 days postoperatively. No postoperative complications or recurrence was identified in any case during the 6- to 55-month follow-up period.

Non-Adhesive Liquid Embolic Agents in Extra-Cranial District: State of the Art and Review of the Literature

This review focuses on the use of “new” generation of non-adhesive liquid embolic agents (NALEA). In literature, non-adhesive liquid embolic agents have mainly been used in the cerebral district; however, multiple papers describing the use of NALEA in the extracranial district have been published recently and the aim of this review is to explore and analyze this field of application. There are a few NALEA liquids such as Onyx, Squid, and Phil currently available in the market, and they are used in the following applications: mainly arteriovenous malformations, endoleaks, visceral aneurysm or pseudoaneurysm, presurgical and hypervascular lesions embolization, and a niche of percutaneous approaches. These types of embolizing fluids can be used alone or in combination with other embolizing agents (such as coils or particles) so as to enhance its embolizing effect or improve its possible defects. The primary purpose of this paper is to evaluate the use of NALEAs, predominantly used alone, in elective embolization procedures. We did not attempt a meta-analysis due to the data heterogeneity, high number of case reports, and the lack of a consistent follow-up time period.

Safety and Effectiveness of Ethylene Vinyl Alcohol Copolymer Embolization of Peripheral High-Flow Arteriovenous Malformations: Results of a Prospective Study

PURPOSE

To prospectively evaluate the efficacy and safety of a new ethylene vinyl alcohol (EVOH) copolymer-based embolic agent in the treatment of symptomatic peripheral arteriovenous malformations (AVMs).

MATERIALS AND METHODS

This prospective single-center study evaluated EVOH embolization with 3 different formulations of EVOH (Squid Peri 12 cP, 18 cP, and 34 cP; BALT Germany GmbH, Düsseldorf, Germany) in patients with symptomatic AVMs. Between April 2018 and October 2019, 36 embolization procedures in 21 patients (3 males and 18 females; mean age, 34.7 years) were performed (inclusion criteria: symptomatic peripheral AVM, ≥14 years of age, and elective embolization). Symptoms, technical aspects (transarterial, transvenous, or percutaneous approach; plug or balloon occlusion), clinical and technical success (defined as the improvement of symptoms and complete angiographic eradication of the AVM nidus), adverse events, and short-term outcomes were assessed.

RESULTS

The mean volume of the embolic agent used per session was 3.4 mL of EVOH 34 cP (standard deviation [SD], ± 5.4), 6.2 mL ± 8.1 of EVOH 18 cP, and 4.6 mL ± 10.1 of EVOH 12 cP. Angiographic success was achieved in 18 patients (85.7%). The mean follow-up was 190 days (range, 90-538 days; median, 182 days). In the follow-up assessment, findings of magnetic resonance imaging showed that 19 patients (90.5%) had a persistent state of devascularization compared with postinterventional angiography. Amelioration or complete elimination of pain was achieved in 90.0% of the patients. One patient experienced a major adverse event; minor adverse events developed in 2 patients.

CONCLUSIONS

In this study, EVOH appeared to be a safe and effective embolic agent in peripheral AVMs and had a low rate of adverse events in a limited number of patients.

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

PURPOSE

To evaluate the safety and efficacy of ethanol embolization of lip arteriovenous malformations (AVMs).

MATERIALS AND METHODS

Seventy-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.

RESULTS

Of 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.

CONCLUSIONS

Ethanol 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.

The Rare Cases of Parotid Gland Arteriovenous Malformations

Arteriovenous malformation (AVM) results from errors in vascular development during embryogenesis; absent capillary beds lead to shunting directly from the arterial to venous circulation. Although it is common in the head and neck region, AVMs located in the parotid gland are quite rare. Here, we report two cases of arteriovenous malformation of the parotid gland that presented to our out-patient setup with swelling in the parotid region and were diagnosed as arteriovenous malformation on histopathological study after surgical resection.

Arteriovenous Malformations-Current Understanding of the Pathogenesis with Implications for Treatment

Arteriovenous malformations are a vascular anomaly typically present at birth, characterized by an abnormal connection between an artery and a vein (bypassing the capillaries). These high flow lesions can vary in size and location. Therapeutic approaches are limited, and AVMs can cause significant morbidity and mortality. Here, we describe our current understanding of the pathogenesis of arteriovenous malformations based on preclinical and clinical findings. We discuss past and present accomplishments and challenges in the field and identify research gaps that need to be filled for the successful development of therapeutic strategies in the future.

Giant parapharyngeal high-flow arteriovenous malformation causing airway compromise: emergency embolo-sclerotherapy via an endovascular-only approach

Head and neck arteriovenous malformations are the commonest extracranial vascular malformations but demonstrate a unique challenge in the limited available surgical options secondary to their intimate association to vital structures. We present a case of middle-aged female patient who presented with threatened upper-airway obstruction and bleeding secondary to a slowly enlarging parapharyngeal arteriovenous malformations. She was treated with an endovascular-only approach with the proximal arteriole branches selectively undergoing embolo-sclerotherapy with an optimal radiological and clinical outcome. We also demonstrate the utility of elective tracheostomy prior to intervention.

Uterine Arteriovenous Malformation: A Pictorial Review of Diagnosis and Management

Uterine arteriovenous malformation (UAVM) is a rare condition and is classified as either congenital or acquired UAVM. Patients with UAVMs usually experience miscarriages or recurrent menorrhagia. Ultrasound is used for the initial estimation of UAVMs. Computed tomography and magnetic resonance imaging are noninvasive and valuable methods that provide good compatibility with digital subtraction angiography to support the diagnosis and treatment of UAVM. Timely diagnosis is crucial to provide appropriate treatment for alleviating complications. This article presents a pictorial and literature review of the current evidence of the diagnosis and management of UAVM.

Endovascular balloon-assisted liquid embolisation of soft tissue vascular malformations: technical feasibility and safety

Purpose

Arteriovenous malformations (AVMs) are abnormal communications between arteries and veins without an intervening capillary system. The best endovascular treatment option for these is unclear and may involve multiple staged procedures using a variety of embolic materials. We report our initial experience using a modified version of a previously published neurointerventional technique to treat soft tissue AVMs with single-stage curative intent.

Materials and methods

Soft tissue AVMs treated endovascularly using either sole arterial or combined arterial and venous balloon-assisted techniques with liquid embolic agents were retrospectively identified over a 3.5 year period (January 2017 to June 2020)) at two centres. Clinical, pre-operative radiological, procedural technical and post treatment details were recorded.

Results

Seven patients were treated for symptomatic soft tissue arteriovenous malformations. These AVMs were located in the peripheral limbs (five), tongue (one) and uterus (one). Curative treatment was achieved in 6/7 patients with one patient requiring a second treatment approximately 1 year later. A variety of liquid embolisation agents (LEAs) including sclerosants and polymers were used. Clinical success rate was 100% following treatment. One patient experienced expected temporary post-operative tongue swelling requiring tracheostomy occurred following embolisation of the lingual AVM. A minor complication in a second patient was due to an access site haematoma developed following treatment of the hand AVM requiring surgical intervention. No long-term sequelae or additional complications were observed.

Conclusion

Endovascular arterial and venous balloon assisted LEA embolization of soft tissue AVMs with curative intent is feasible. This technique may provide an alternative treatment option for achieving durable occlusion for complex soft tissue AVMs.

Management of symptomatic adult penile urethral arteriovenous malformation

We present the Case of a 23-year-old male with a history of recurrent spontaneous urethral bleeding due to an arteriovenous malformation (AVM) of his corpus spongiosum which abutted his penile urethra. AVMs are often congenital but can also be related to prior trauma. The literature on male genital AVMs is primarily limited to pediatric AVMs of the scrotum or glans penis with one report of adult urethral AVM in the setting of known trauma. We describe a novel presentation of atraumatic adult male genital AVM treated by surgical repair with resolution of bleeding.

Rare Diseases of the Orbit

This article provides an overview of rare orbital diseases. Congenital malformations, inflammatory diseases, benign and malignant neoplasias are described. Although it represents a relatively small area of the body the orbit contains multiple different tissues. Therefore, a great variety of diseases can be found within the orbital space. That is the reason, why both the completeness and the level of detail in the description of particular diseases must be somewhat limited. Nevertheless, clinical manifestations, important aspects of diagnosis, treatment strategies, and, when specific data are available, the prognosis are described. The authors tried to highlight the most characteristic aspects of the different diseases to describe their relevant aspects in spite of the brevity of the subsections.

Congenital renal arteriovenous malformation: a rare cause of visible haematuria

We report a case of renal arteriovenous malformation (AVM) and describe its angioarchitecture and endovascular management. A 28-year-old male patient presented with visible painless haematuria. CT of the abdomen showed a right renal AVM. Digital subtraction angiography of the right renal vessels showed an AVM of middle and lower pole segmental arteries with communication to a large saccular aneurysm, which was arising from the right main renal vein. Complete occlusion of the AVM was done by using glue (a mixture of n-butyl-cyanoacrylate and lipiodol), resulting in nonvisualisation of the aneurysm on angiography. His vital signs were stable during the procedure. Follow-up CT after 12 months showed no residual flow in the aneurysm, normal upper pole renal parenchyma and nonvisualisation of AVM. Early diagnosis of this clinical entity is of paramount importance for proper management as it can cause massive blood loss and rapid clinical deterioration.

Endovascular approach for arteriovenous limb malformations: a single center experience

BACKGROUND

To assess imaging findings, describe endovascular technical aspects and analyzed procedural outcomes in a population of patients underwent limb arteriovenous malformation (LAVMs).

METHODS

From January 2015 to December 2018, all consecutive patients underwent an endovascular procedure for ICD-9-CM codex for arteriovenous malformation problems were retrospective reviewed. Among these, patients with LAVMs were selected. Demographic, preoperative imaging, interventional and postprocedural data were collected for each patient and procedure. The International Society of Vascular Anomalies, the Cho-Do angiographic classification and the Schobinger clinical stage were used to describe disease type, aspect and clinical severity. Angiographic and clinical outcomes were also described.

RESULTS

During the study period, 76 intervention for AVMs were performed in 52 patients. Among these, 26 LAVMs were selected and analyzed in 21 patients (number of LAVMs per patient: 1.2±0.5), 14 affecting upper limbs, 17 lower limbs. Pain, discomfort and swelling were main symptoms reported (95%, 90% and 62%, respectively). Ultrasound scan, computed angiography tomography and magnetic resonance angiography were used - alone or in combination - as preoperative imaging in 67%, 62% and 48% of patients, respectively. Cho-Do class ≥3 was described in 70% of treated LAVMs and a Schobinger stage ≥2 in more than 90%. Ipsilateral femoral access with a 5F introducer was preferred. Selective embolization with glue was the most preferred technique (57%), in combination or not with microsphere embolization (19%) and/or direct nidus sclerotherapy (14%). Optimal and suboptimal results were achieved in 86% of cases. Further interventions were performed in 52% of cases, with more than two interventions in 29% of cases.

CONCLUSIONS

Quality of life, clinical picture and anatomical structure are items of paramount importance during preoperative LAVMs endovascular treatment planning. Treatment must be focused on LAVMs type, minimizing invasiveness and number of interventions, although secondary intervention rate remains quite high.

RhoA activation-mediated vascular permeability in capillary malformation-arteriovenous malformation syndrome: a hypothesis

Capillary malformation-arteriovenous malformation (CM-AVM) syndrome is a class of capillary anomalies that are associated with arteriovenous malformations and arteriovenous fistulas, which carry a risk of hemorrhages. There are no broadly effective pharmacological therapies currently available. Most CM-AVMs are associated with a loss of RASA1, resulting in constitutive activation of RAS signaling. However, protein interaction analysis revealed that RASA1 forms a complex with Rho GTPase-activating protein (RhoGAP), a negative regulator of RhoA signaling. Herein, we propose that loss of RASA1 function results in constitutive activation of RhoA signaling in endothelial cells, resulting in enhanced vascular permeability. Therefore, strategies aimed at curtailing RhoA activity should be tested as an adjunctive therapeutic approach in cell culture studies and animal models of RASA1 deficiency.

Treatment Outcomes of Embolization for Peripheral Arteriovenous Malformations

PURPOSE

To evaluate treatment outcomes of embolization for peripheral arteriovenous malformations (AVMs) in a tertiary referral center where ethanol is the primary agent of choice.

METHODS

A retrospective study was performed of 93 patients (median age, 31 years; range, 2-66 years) with peripheral AVMs treated with embolization (n = 442; median, 2 per patient; range, 1-82) between January 2010 and July 2016. Ethanol was used in most cases (n = 428; 97%). AVMs were classified as type I (n = 3), type II (n = 57), type IIIa (n = 5), type IIIb (n = 15), and type IV (n = 13) according to the Yakes classification system. Effectiveness of embolization was based on AVM devascularization on angiography: 100% (total), 90%-99% (near-total), 70%-90% (substantial), 30%-70% (partial), and 0%-30% (failure). Complications were graded according to the Society of Interventional Radiology classification.

RESULTS

In 69% of patients, 70%-100% devascularization was achieved. Total and near-total occlusion of the nidus were more often achieved in AVMs of types I and IIIa (both 100%) than in AVMs of types II, IIIb, and IV (56%, 67%, and 39%, respectively; P = .019). A total of 109 complications were identified: 101 minor (22.9%) and 8 major (1.8%). Major complications included wounds (n = 5), false aneurysm (n = 1), finger contracture (n = 1), and severe pain (n = 1) requiring therapy. The patient complication risk was significantly affected by the number of procedures (relative risk = 2.0; P < .001). Age, AVM location, and angioarchitecture type did not significantly affect complication risk.

CONCLUSIONS

AVM embolization resulted in 70%-100% devascularization in 69% of patients, with few major complications. This study indicates that the type of AVM angioarchitecture affects the number of procedures needed and the achievability of AVM devascularization.

Cell-free DNA as a diagnostic analyte for molecular diagnosis of vascular malformations

Purpose:

Vascular malformations (VM) are primarily caused by somatic activating pathogenic variants in oncogenes. Targeted pharmacotherapies are emerging but require molecular diagnosis. Since variants are currently only detected in malformation tissue, patients may be ineligible for clinical trials prior to surgery. We hypothesized that cell-free DNA (cfDNA) could provide molecular diagnoses for patients with isolated VM.

Methods:

cfDNA was isolated from plasma or cyst fluid from patients with arteriovenous malformations (AVM), venous malformations (VeM), or lymphatic malformations (LM), and assayed for known pathogenic variants using droplet digital PCR (ddPCR). Cyst fluid cfDNA from an independent cohort of LM patients was prospectively screened for variants using a multiplex ddPCR assay.

Results:

Variants were detected in plasma cfDNA in patients with AVM (2/8) and VeM (1/3). Variants were detected in cyst fluid cfDNA (7/7) but not plasma (0/26) in LM patients. Prospective testing of cyst fluid cfDNA with multiplex ddPCR identified variants in LM patients who had never undergone surgery (4/5).

Conclusion:

Variants were detected in plasma from AVM and VeM patients, and in cyst fluid from patients with LM. These data support investigation of cfDNA-based molecular diagnostics for VM patients which may provide opportunities to initiate targeted pharmacotherapies without prior surgery.

Successful Percutaneous Treatment of an Arteriovenous Malformation of the Toe

Arteriovenous malformations (AVMs) of the toe are a rare entity. To the author's knowledge, there are only 2 published case reports, and both patients underwent amputation of the affected digits. Little is known about the optimal treatment of AVMs involving the toe. The authors present the case of a 20-year-old male with a large AVM of the second toe, which was successfully treated with intra-arterial sodium tetradecyl sulfate. Percutaneous treatment of these lesions is possible and should be considered before amputation.

Intraosseous Arteriovenous Malformations in the Extremities Managed with Coils and Absolute Ethanol Treatment

BACKGROUND

The extremity intraosseous arteriovenous malformations (AVMs) are rare high flow vascular lesions for which the treatment remains challenging. The aim of the study wasto assess treatment methods, interim results, and complications of coils and absolute ethanol in managing extremity intraosseous AVMs via direct puncture approach.

METHODS

From 2009 to 2017, 12 patients (mean age, 27.5 years; range, 3-54 years) with extremity intraosseous AVMs underwent staged coils and absolute ethanol treatment via the direct puncture approach. All patients were symptomatic before the procedure as per the Schobinger staging system. The mechanical detachable coils and undetachable coils were used first followed by the injection of absolute ethanol used as a sclerosant agent via a direct puncture approach. Follow-up evaluation (6 to 72 months; mean, 23.5 months), including imaging and symptoms and signs, was performed in all patients.

RESULTS

Twenty-seven absolute alcohol procedures were performed for patients with intravascular sclerosis (range: 1-3, mean: 2) with one procedure required per patient (n = 2), 2 per patient (n = 5), or 3 per patient (n = 5). The average stretched length of the total coils per patient was 843.33 cm. The amount of absolute ethanol used ranged from 10 mL to 45 mL (mean, 25.69 mL) in a single session. Nine of twelve patients (75%) exhibited complete responses, and 3 patients (25%) exhibited partial responses. One patient experienced minor complication of transient motor nerve injury and completely recovered half a month later. No major complications occurred.

CONCLUSIONS

The study provides strong evidence, suggesting that direct puncture and coils with absolute ethanol approach is an effective and safe treatment in patients with extremity intraosseous AVMs, yielding minor complications and good results.

Temporal Evolution and Management of Fast Flow Vascular Anomalies in PTEN Hamartoma Tumor Syndrome

Phosphatase and tensin homolog (PTEN) hamartoma tumor syndrome (PHTS) is characterized by formation of recurrent benign tumors described as PTEN hamartoma of soft tissue that may contain fast flow vascular anomalies (FFVA). The purpose of this study is to review the temporal evolution and management of FFVA in PHTS. A retrospective review of 22 patients (9 males), age 1 to 18 (median 9) years diagnosed with PHTS at a tertiary care pediatric hospital between October 2002 and August 2017 revealed 4 patients with FFVA. Imaging, management, and treatment complications were reviewed. During median follow-up of 8 (range: 4-13) years, ultrasound and magnetic resonance imaging performed for recurrent pain, showed progressive increase in the size of hamartomas and development of new FFVA in three-fourth patients. Medical management included pain medications, oral sirolimus, and physical and psychiatric therapy. Surgical excision of hamartoma ( n  = 1) resulted in recurrence within 3 months. Between 4 and 24 (average 1.5/year) embolizations were performed per patient. Pain related to FFVA responded well to embolization. Pain secondary to PTEN hamartoma responded poorly to percutaneous sclerosant injection, but demonstrated improvement with sirolimus. There was no correlation between serum sirolimus levels and frequency/timing of recurrence of FFVA/hamartoma. Complications included sclerosant migration into digital arteries ( n  = 1), subclavian vein stenosis due to glue migration ( n  = 1), oral mucositis ( n  = 4), and elevated triglycerides ( n  = 4). Patients with PHTS present with recurrent pain requiring life-long management with a multi-disciplinary team. Pain due to FFVA responds to embolization, and pain due to hamartoma responds to sirolimus. This improves quality of life, but does not prevent disease progression.