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

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

BACKGROUND

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Overview of peripheral arteriovenous malformations: From diagnosis to treatment methods

Based on the latest classification by the International Society for the Study of Vascular Anomalies in 2018, vascular malformations (VMs) can be categorized into simple, combined VMs of major named vessels, and VMs associated with other anomalies. Simple VMs include lymphatic, venous, capillary, and arteriovenous malformations (AVMs). AVMs represent disorders of direct arteriovenous shunts caused by the absence of a capillary bed between the involved arteries and veins. This abnormal vascular communication causes arterial blood to accumulate in the venous vessels, thus resulting in venous hypertension and characteristic clinical manifestations, such as pulsation, tremors, and elevated temperature. AVMs can occur sporadically or as manifestations of syndromic lesions and are considered among the most complex and challenging VMs. The diagnosis and treatment of AVMs can vary depending on the lesion location and associated clinical symptoms, thus complicating their management. Herein, we discuss peripheral AVMs in terms of their clinical manifestations, imaging examinations, and staging systems to provide a comprehensive reference for the treatment, evaluation methods, and follow-up procedures for this vascular anomaly.

Eradication of the nidus in arteriovenous malformations with a dominant outflow vein in the lower extremities using coils and absolute ethanol

OBJECTIVE

In the present study, we summarize our experience in locating the nidus of arteriovenous malformations (AVMs) with a dominant outflow vein (DOV) in the lower extremities and eradicating the nidus with ethanol and coils.

METHODS

Twelve patients with lower extremity AVMs who underwent ethanol embolization combined with DOV occlusion from January 2017 to May 2018 were enrolled in the present study. Selective angiography was used to locate the nidus of the AVMs, which was eradicated using ethanol and coils via the direct puncture pathway. All treated patients underwent postoperative follow-up (mean, 25.5 months; range, 14-37 months).

RESULTS

The 12 patients underwent a total of 29 procedures (mean, 2.4; range, 1-4) with 27 detachable coils and 169 Nester coils (Cook Medical Inc, Bloomington, IN). Of the 12 patients, 7 (58.3%) had a complete response and 5 (41.7%) a partial response. Three patients (25%) had minor complications such as blister and superficial skin ulcers during follow-up. However, they recovered spontaneously and completely. No major complications were recorded.

CONCLUSIONS

Ethanol embolization combined with coil-assisted DOV occlusion has the potential to eradicate the nidus of lower extremity AVMs with acceptable complication rates.

Clinical Outcome and Quality of Life of Multimodal Treatment of Extracranial Arteriovenous Malformations: The APOLLON Study Protocol

PURPOSE

Arteriovenous malformations (AVMs) as rare diseases are diagnostically and therapeutically challenging. Due to the limited evidence regarding treatment outcome, prospective data are needed on how different treatment regimens affect outcome. The aims of this prospective trial are to determine effectiveness, safety, and clinical outcome of multimodal treatment in patients with extracranial AVMs.

MATERIALS AND METHODS

After clinical and magnetic resonance imaging (MRI)-based diagnosis and informed consent, 146 patients (> 4 years and < 70 years) undergoing multimodal therapy in tertiary care vascular anomalies centers will be included in this prospective observational trial. Treatment options include conservative management, medical therapy, minimally invasive image-guided procedures (embolization, sclerotherapy) and surgery as well as combinations of the latter. The primary outcome is the patient-reported QoL 6 months after completion of treatment using the short form-36 health survey version 2 (SF-36v2) and the corresponding short form-10 health survey (SF-10) for children. In addition, clinical presentation (physician-reported signs), MRI imaging (radiological assessment of devascularization), recurrence rate, and therapeutic safety will be analyzed. Further follow-up will be performed after 12, 24, and 36 months. Moreover, liquid biopsies are being obtained from peripheral blood at multiple time points to investigate potential biomarkers for therapy response and disease progression.

DISCUSSION

The APOLLON trial is a prospective, multicenter, observational open-label trial with unequal study groups to generate prospective evidence for multimodal treatment of AVMs. A multicenter design with the potential to assess larger populations will provide an increased understanding of multimodal therapy outcome in this orphan disease.

TRIAL REGISTRATION

German Clinical Trials Register (identification number: DRKS00021019) https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00021019 .

The Efficiency and Safety of Ethanol Sclerotherapy for Labial Arteriovenous Malformations

BACKGROUND

AND PURPOSE: Labial arteriovenous malformations, usually with accompanying cosmetic defects, pain, and bleeding, are aggressive with characteristics of high risk of recurrence and absence of effective treatment. This study presents a technique of sclerotherapy for labial arteriovenous malformations.

METHODS

Patients with labial arteriovenous malformations were treated with percutaneous ethanol sclerotherapy with or without polyvinyl alcohol particle embolization. The efficiency, complications, and recurrence rate were analyzed with imaging and clinical follow-up data.

RESULTS

Of the 15 patients, all patients received one or more treatment sessions, from which eight realized a cure (53.3%) and five had remission (33.3%). Two patients who did not achieve an effective result await further treatment. Four (26.7%) patients treated with ethanol sclerotherapy combined with polyvinyl alcohol particle embolization developed recurrence. No recurrence occurred in patients treated with only sclerotherapy (mean ± SD follow-up 17.2 ± 8.1 months). Thirteen patients developed transient complications: swelling, mild bleeding, and blistering. One patient had a postoperative scar of about 0.5 cm.

CONCLUSIONS

Ethanol sclerotherapy appears effective as a treatment for labial arteriovenous malformations. Careful application of the treatment can reduce the occurrence of complications.

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.

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.

Musculoskeletal Interventional Radiology in the Pediatric Population: State of the Art

Interventional radiology procedures have been proven to be as effective as traditional surgery but usually are characterized by lower morbidity rates. In this article, the most diffuse IR treatments for pediatric lesions are reviewed with the aim of describing main advantages and drawbacks. Ablation procedures (in particular RFA and MRgFUS) are widely used for the management of osteoid osteoma and osteoblastoma whereas intracystic injection of methylprednisolone acetate is performed for simple bone cysts. Sclerosing agents and where possible, selective arterial embolization are used for treatment of aneurysmal bone cysts and other vascular malformations. In the management of malignant muscoloskeletal tumors, the role interventional radiology is mainly represented by percutaneous biopsies, and by adiuvant selective embolizations in presence of hypervascular lesions to be submitted to surgery.

Peripheral Arteriovenous Malformations: Imaging and Endovascular Management Strategies

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

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

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

Tratamiento de malformaciones y tumores vasculares, en un centro de referencia en Bogotá

Introducción. Las malformaciones vasculares son anomalías que están presentes desde el nacimiento, no desaparecen y pueden crecer a lo largo de la vida. Se ha demostrado en estudios retrospectivos que la terminología para clasificar las anomalías vasculares es inexacta en un 69 % de casos, por lo que se hace un diagnostico inadecuado y en un 53 % de casos se brinda al paciente y su familia una información incorrecta del tratamiento y el curso clínico. Métodos. Estudio prospectivo longitudinal, realizado entre 2016 y 2019, donde se incluyeron pacientes con anomalías vasculares, que consultaron a nuestra institución, fueron valorados por el servicio de cirugía vascular, se hizo un plan diagnóstico y manejo integral, vía endovascular, quirúrgica o mixta, de acuerdo con cada caso. Resultados. La malformación más común fue la de tipo venoso, en el 40,3 % de los casos. Se realizó manejo endovascular en el 93,1 % de casos de malformaciones vasculares y quirúrgico en el 6,9 %. La mejoría de los síntomas que motivaron la consulta fue del 100 % para los tumores vasculares y del 70,8 % para las malformaciones. Sin embargo, los resultados son heterogéneos. Discusión. Es necesario realizar un adecuado diagnóstico de las anomalías vasculares, para alcanzar un tratamiento eficaz, con mejoría de los síntomas.

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

PURPOSE

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

MATERIALS AND METHODS

Eighty-four type II AVMs in the body or extremity of 79 patients who underwent AVM treatment from 1996 to 2017 were retrospectively subclassified according to the angiographic morphology of the draining vein as type IIa (arterioles shunt to focal segment of single draining vein), type IIb (arterioles shunt to venous sac with multiple draining veins), and type IIc (arterioles shunt along long segment of draining vein). Coil and ethanol embolization of the focal or long segment of the draining vein or the venous sac was performed with direct puncture or transvenous approach according to subtype. Treatment outcomes, number of treatment sessions, and complications were analyzed.

RESULTS

AVM cure (ie, complete embolization) rates were 95%, 76%, and 65% in types IIa, IIb, and IIc AVMs, respectively. The cure rate of type IIa AVMs was significantly better than that of type IIc AVMs (P = .015). Median numbers of treatment sessions were 1 in types IIa and IIb AVMs and 2.5 in type IIc AVMs, with a significant difference between type IIc and the other 2 types (P < .05). Minor complications occurred in 20% of patents and major complications occurred in 7%.

CONCLUSIONS

The cure rate of type IIa AVMs was significantly better than that of type IIc AVMs, which also required significantly more treatment sessions than the other 2 types.

Arteriovenous Malformations: Syndrome Identification and Vascular Management

PURPOSE OF REVIEW

Vascular malformations represent a poorly understood set of conditions that create considerable diagnostic and therapeutic confusion. Historically, extensive surgical resections yielded poor results. More recently, the treatment paradigm has shifted to endovascular therapy such that embolization and sclerotherapy are now considered the first line of treatment. Although there is still a role for traditional surgical techniques, it is now most commonly integrated with endovascular therapies in a hybrid fashion. The goal of this review is to provide a greater understanding of the diagnosis and treatment of vascular malformations.

RECENT FINDINGS

Vascular malformations can be high-flow (arteriovenous shunting) or low-flow (venous or lymphatic). Clinical presentation and treatment is different for each. Treatment of high-flow lesions must be directed at reducing or eliminating the nidus, usually via super-selective catheterization and embolization. Low-flow lesions are usually treated by direct injection of sclerosing agents under fluoroscopic or ultrasound guidance. The cornerstone of managing patients with vascular malformations is making the proper diagnosis, which is often challenging. Even after a diagnosis is made, therapy itself may be challenging and generate frustration among patients and providers. Frequently, the treatment of vascular malformations is characterized by only slow and incremental improvements without complete lesion eradication. By combining a thorough understanding of the vascular malformation disease process with an array of endovascular techniques, vascular interventionalists may contribute greatly to the care of these patients.

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

PURPOSE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Angioarchitecture of Hereditary Arteriovenous Malformations

This article describes three hereditary conditions known to be associated with arteriovenous malformation (AVM), along with their clinical and imaging features and angiographic angioarchitecture. Hereditary hemorrhagic telangiectasia, capillary malformation-AVM (CM-AVM), and PTEN tumor hamartoma syndrome are conditions with autosomal dominant inheritance, caused by mutations in different molecular pathways, which frequently present with symptomatic AVMs. Imaging biomarkers, including sites of predilection, angioarchitecture, and tissue overgrowth patterns, are helpful in identifying these patients and selecting appropriate treatment.

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

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

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

PURPOSE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Salvage treatment of hemorrhagic arteriovenous malformations in jaws

OBJECTIVE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Treatment of tongue cavernous haemangioma with direct puncture and sclerotization with ethanol

BACKGROUND

Haemangiomas of tongue are rare type of malformations. They can be treated mostly conservatively but in some cases they need more aggressive treatment with preoperative intra arterial embolization and surgical resection. Lesions of tongue that are localized superficially can also be treated with direct puncture and injection of sclerosing agent (absolute ethanol).

CASE REPORT

We present a case of a 48 years old female patient, where we performed embolization of cavernous haemangioma with mixture of absolute ethanol and oil contrast. After the procedure the patient received analgetics and antioedematous therapy. After the sclerotization the planed surgery was abandoned. Control MRI examinations 6 and 12 months after the procedure showed only a small remnant of haemangioma and no signs of a larger relapse.

CONCLUSIONS

In our case the direct puncture of haemangioma and sclerotherapy with ethanol proved to be a safe and effective method to achieve preoperative devascularization of the lesion. Direct puncture of the lesion is not limited by the anatomy of the vessels or vasospasm, which can occur during the intra-arterial approach.

Early symptoms and long-term clinical outcomes of distal limb's cutaneous arterio-venous malformations: a retrospective multicentre study of 19 adult patients

INTRODUCTION

Cutaneous arterio-venous malformations (AVM) are high-flow vascular malformations made up of a direct link between arteries and veins without intermediary capillary space. 'Distal limb's AVM', which mean involving hands or feet, are rare and their functional prognosis is often poor. Little is known about their early clinical symptoms. The objectives of this study were to identify early clinical symptoms of distal limb's cutaneous AVMs and to determine their long-term clinical outcome.

METHODS

A retrospective study was carried out including adult patients who had distal limb's AVM, who were followed up between January 2000 and November 2013 in two regional tertiary care centres. The information was collected from patients' clinical records and completed by a structured telephone questionnaire.

RESULTS

Nineteen patients were included in the study: four (21%) with foot AVM and 15 (79%) with hand AVM. The first clinical symptoms were as follows: swelling (47%), pain (47%), one or several venous dilatations (37%) and rarely abnormal skin colour, hyperthermia and pulsating sensation. The median diagnosis delay was 9 years after the onset of first manifestations. Amongst the 17 patients who underwent a treatment, 53% had embolotherapy session(s), 12% surgery and 35% had both. After an average follow-up of 57.6 months, 31% of the 13 patients contacted who were receiving treatment were in complete remission; 31% had partial remission; 15% had relapse after initial improvement and 23% had treatment failure. Overall, 74% of patients had a serious development of the AVM: 37% had digital or hand amputation, and 42% remained symptomatic and/or unstable.

CONCLUSION

This study suggests that initial manifestations of distal limb's AVMs are discreet and non-specific, leading to a diagnosis delay of about 10 years, with poor prognosis. Doctors should evoke the diagnosis earlier, when these symptoms are shown: pain and/or swelling, sometimes with a large vein.

Vascular anomalies: classification, imaging characteristics and implications for interventional radiology treatment approaches

The term vascular anomaly represents a broad spectrum of vascular pathology, including proliferating vascular tumours and vascular malformations. While the treatment of most vascular anomalies is multifactorial, interventional radiology procedures, including embolic therapy, sclerotherapy and laser coagulation among others, are playing an increasingly important role in vascular anomaly management. This review discusses the diagnosis and treatment of common vascular malformations, with emphasis on the technique, efficacy and complications of different interventional radiology procedures.

[Potential and limitations of modern embolization therapy]

Correct clinical and angiographic classification of vascular anomalies, including consideration of their flow pattern (high-flow versus low-flow), is the basis of accurate indications for minimally invasive therapy modalities such as embolization. Technical advancements and miniaturization of catheter materials (including steerable microwires, flow-directed microcatheters and detachable tips) gained access for embolotherapy to lesions anywhere in the body. The aim of embolization, which is mainly indicated for therapy of high-flow arteriovenous malformations, is the complete, permanent occlusion of the lesion nidus. Nowadays, embolotherapy is performed using permanent liquid embolization agents, in multiple staged sessions. This technique reduces complications such as ischemic necrosis and peripheral nerve lesions compared to alcohol embolization. Sole occlusion of the arterial inflow by surgical resection or interventional coil application is considered obsolete. The size of the lesion and the high treatment costs limit the use of embolotherapy.

Head and neck arteriovenous malformations: results of ethanol sclerotherapy

BACKGROUND AND PURPOSE

Peripheral AVM is a locally aggressive disease with a high tendency to recur; its treatment is complex, especially in the anatomically delicate head and neck area. Here, we report results of ethanol sclerotherapy for head and neck AVM and discuss its potential use for peripheral AVM.

MATERIALS AND METHODS

We retrospectively assessed degree of AVM eradication, complications, and clinical or imaging signs of recurrence for 19 patients treated with ethanol sclerotherapy for head and neck AVM (1 intraosseous, 18 soft-tissue AVMs).

RESULTS

Of the 19 patients, 11 had complete eradication of arteriovenous shunting at DSA, with 1 recurrence (mean follow-up 15 months), and for 7 patients, treatment is ongoing. During 59 treatment sessions, 12 patients experienced 14 complications, 1 leading to permanent functional damage.

CONCLUSIONS

Ethanol sclerotherapy has potential for complete eradication of head and neck AVM with low recurrence within the first year after completion of treatment. Complete eradication may require several treatment sessions during which complications should be minimized with careful techniques.

PERMANENT ULNAR NERVE PALSY AFTER EMBOLOTHERAPY OF ARTERIOVENOUS MALFORMATION AROUND THE ELBOW

Permanent nerve palsy is an extremely rare but critical complication after embolotherapy of arteriovenous malformations of the extremities. The authors present a case of permanent ulnar nerve palsy after embolotherapy of an arteriovenous malformation around the elbow, and caution that transcatheter embolotherapy of arteriovenous malformations located close to major neurovascular structures must be carefully planned and individualized.

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

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