High-flow Vascular Malformations Research Articles

Adjunctive venous sinus stenting in transvenous embolization of vein of Galen malformations.

Vein of Galen malformations are congenital arteriovenous malformations primarily treated by endovascular embolization via transarterial or transvenous approaches. transvenous embolization can be utilized to close the malformation but may be difficult in patients with venous stenosis or blockages, which drive venous hypertension and lead to significant neurologic consequences. Here, we illustrate the atypical placement of an intracranial venous sinus stent to improve outflow after transvenous embolization in pediatric patients with the vein of Galen malformation. A retrospective review of clinical databases at two high-volume endovascular centers from January 2018 to March 2023 identified all vein of Galen malformation patients who received a venous sinus stent during transvenous embolization. Clinical data, imaging, angioarchitecture, operative details, postoperative management, and follow-up were reviewed. Three patients presented for transvenous embolization after multiple staged transarterial embolizations of their vein of Galen malformation. Transvenous access was complicated by lateral sinus stenosis, which was temporarily relieved by balloon angioplasty. After transvenous embolization by pressure cooker technique, the dural sinuses were stented using the existing venous guide catheter. Venous angiography demonstrated improved flow across the stenosed areas and post-embolization angiography demonstrated normalized venous drainage with widely patent stents. One patient experienced postoperative oculomotor nerve palsy unrelated to the stent placement. All patients demonstrated a complete cure of their vein of Galen malformations with patent venous sinus stents on follow-up. In patients with the vein of Galen malformation and venous hypertension receiving transvenous embolization, venous sinus stenting may be a safe and effective option to reduce aberrant cortical venous drainage and improve normal outflow. Further studies are warranted to investigate its benefit in high-flow vascular malformations.

Deep learning-based differentiation of peripheral high-flow and low-flow vascular malformations in T2-weighted short tau inversion recovery MRI.

Differentiation of high-flow from low-flow vascular malformations (VMs) is crucial for therapeutic management of this orphan disease. A convolutional neural network (CNN) was evaluated for differentiation of peripheral vascular malformations (VMs) on T2-weighted short tau inversion recovery (STIR) MRI. 527 MRIs (386 low-flow and 141 high-flow VMs) were randomly divided into training, validation and test set for this single-center study. 1) Results of the CNN's diagnostic performance were compared with that of two expert and four junior radiologists. 2) The influence of CNN's prediction on the radiologists' performance and diagnostic certainty was evaluated. 3) Junior radiologists' performance after self-training was compared with that of the CNN. Compared with the expert radiologists the CNN achieved similar accuracy (92% vs. 97%, p = 0.11), sensitivity (80% vs. 93%, p = 0.16) and specificity (97% vs. 100%, p = 0.50). In comparison to the junior radiologists, the CNN had a higher specificity and accuracy (97% vs. 80%, p < 0.001; 92% vs. 77%, p < 0.001). CNN assistance had no significant influence on their diagnostic performance and certainty. After self-training, the junior radiologists' specificity and accuracy improved and were comparable to that of the CNN. Diagnostic performance of the CNN for differentiating high-flow from low-flow VM was comparable to that of expert radiologists. CNN did not significantly improve the simulated daily practice of junior radiologists, self-training was more effective.

Arteriovenous fistula of the mandible: a case report

Intraosseous arteriovenous malformations (AVM) are uncommon high-flow vascular malformation that can affect the maxilla or mandible. AVM may present with aspecific and misleading signs and symptoms. The diagnosis is often accidental and bleeding may represent the first symptom. Radiographically, there are few characteristic features and misdiagnosis is easy. Here we report the case of a young male affected by arteriovenous fistula on the right side of the mandible initially misdiagnosed as a cystic lesion. The patient underwent transarterial embolization of the vascular malformation and subsequently the lesion was surgically removed. 1-year follow-up showed complete healing of the mandibular bone and absence of recurrence. Intraosseous arteriovenous malformations are rare entities. However, due to their harmfulness, both clinicians and radiologists must be aware of this type of lesion and should always consider them in the differential diagnosis of osteolytic lesions.

Large Medically Resistant Intramuscular Fast-Flow Vascular Anomaly in a Young Adult Patient Managed With Embolization and Cryoablation

Background: Mitogen-activated protein 2 kinase (MAP2K) intramuscular high-flow vascular anomaly is a benign vascular lesion, thought to be congenital, with an indolent course. Years after initial presentation, symptoms may manifest due to abrupt growth. Case presentation: This report describes a case of a young female who presented with a MAP2K high-flow vascular anomaly with recalcitrant pain, resistant to a trial of Sirolimus and Trametinib. Significant lesion size reduction and pain resolution were achieved with a combination of preablation embolization followed by cryoablation. Follow-up of 5 years informs lesion reduction and stability. Conclusion: Using a multi-method approach (embolization then ablation) can be considered in the treatment of MAP2K high-flow vascular malformations resistant to medical therapy.

Botriomycoma on arteriovenous malformation

Botriomycoma and Arteriovenous Malformation (AVM) are two different entities. The botriomycoma or also called Pyogenic Granuloma (GP) is a vascular tumor benign of the skin and mucous membranes, often post-traumatic, whereas AVM is a high flow vascular malformation. The occurrence of GP on AVM is extremely rare. We report an original clinical image of this association. This is a 12 year old patient, without any notable pathological history, who consults for a fleshy nodule bleeding post traumatic injury to the forehead (Figure 1A). Clinical examination reveals a warm underlying mass and pulsatile which dates back to the age of 7 years. The diagnosis is suggested clinically and by Doppler ultrasound, and confirmed intraoperatively (Figure 1B) and after histological study of the specimen excision. The diagnosis was made after elimination of other causes: Isolated GP, GP on fistula arteriovenous and others.

Pregnancy with Peripheral Arteriovenous Malformation

22 years old primigravida with 37 weeks singleton gestation was admitted with profuse bleeding from swelling over left anterior superior iliac spine region. Ultrasound findings suggested a high flow vascular malformation with feeder from left common femoral artery. Bleeding was managed conservatively with pressure bandage. Delivery was uneventful. Live female baby of 2.045 kg was delivered by spontaneous vaginal delivery at 38 weeks. After 4 weeks of delivery vascular malformation was confirmed with angiography and treated successfully with endovascular embolization of the major arterial feeder. In periodic follow up until 6 months, no further complication was reported by the patient.

Approach to the Management of Vascular Malformations of Head and Neck and Its Challenges: An Institutional Experience

Abstract Background: Vascular malformations (VMs) in the region of the head and neck are a complex group of lesions that present with serious challenges in diagnosis and management. We sought to study the efficacy and safety of a therapeutic algorithm emphasizing multimodal management in the treatment of head and neck VMs. Methodology: A retrospective study was conducted reviewing all the patient information from the database who were treated for VM of the head and neck at the institution. Patients who presented during the period between January 2012 and December 2022 were included in the study. Conservative care, sclerotherapy, embolization, surgical excision, or a combination of these techniques were among the management options based on the clinical profile of the patient as well as the characteristics of the lesion. Results: 91 VMs in the region of the head and neck included 45 (49%) males and 46 (51%) females, with an age range of between 4 years and 71 years (mean 23.9 ± 14.06 years). There were 53 low-flow vascular malformations (LFVMs), of which 6 (11.9%) were managed conservatively, 26 (49.05%) were treated with sclerotherapy, 20 (37.7%) underwent excision, and 1 (1.8%) was treated with combination therapy. Of the 38 high-flow vascular malformations (HFVMs), 12 (31.5%) were treated with arterial embolization, 13 (34.2%) were primarily resected, 2 (5.2%) with excision and reconstruction, 5 (13.1%) underwent embolization and excision, and 1 (2.6%) underwent emergency external carotid artery ligation. In the LFVM group, response to sclerotherapy led to improvements in 24 (92%) patients, while surgical resection led to improvements in 20 (100%) individuals. In the HFVM group, embolization therapy improved 9 (75%), combination therapy improved 5 (100%), and surgical resection improved 15 (100%) of the patients. Conclusions: In our experience, the implementation of a multimodal management algorithm has had favorable outcomes with an acceptable complication rate in head and neck VMs.

BG09 RASA1 exon deletion in a neonate with vascular malformations

Abstract A full-term infant was noted to have a large, macular, pale-pink vascular birthmark across the left side of the chest, extending to the upper arm. Three smaller pale-pink irregular birthmarks on the elbow, thigh and flank were noted, as was an enlarged left upper arm. He had an oxygen dependency shortly after birth for which he required admission to the neonatal unit. A detailed history revealed that his father, paternal grandmother and aunt had similar birthmarks. His paternal aunt had an episode of bleeding from a spinal arteriovenous malformation (AVM) in her teens, which had been investigated with genetic testing by Sanger sequencing, but this did not identify a variant in RASA1. Following involvement from the dermatology, neonatology, genetics and radiology teams, investigations were organized. Findings included a high-flow vascular malformation with arteriovenous shunting on magnetic resonance imaging (MRI) of the left arm, normal MRI head and spine, and normal cardiac anatomy. Genetic testing by next-generation sequencing detected a heterozygous exon 21–23 deletion in RASA1. A diagnosis of capillary malformation–AVM syndrome (CM–AVM) was confirmed. Results of genetic testing of the father are awaited. Referral to a tertiary centre for consideration of management of AVM is underway. CM–AVM is a rare autosomal dominant condition. Pathogenic variants in RASA1 result in a lack of functional p120-RasGAP protein, which leads to abnormalities in angiogenesis, although this pathway is not well understood (Wooderchak-Donahue W, Johnson P, McDonald J et al. Expanding the clinical and molecular findings in RASA1 capillary malformation-arteriovenous malformation. Eur J Hum Genet 2018; 26:1521–36). Cutaneous vascular malformations, classically pink–red with a pale halo, are the most consistent cutaneous manifestation, but they may be subtle and can mimic other vascular birthmarks such as segmental infantile haemangioma, salmon patches or port wine stain. In our patient, pale halos were not apparent until 4 months of age. Identification is important as life-threatening complications from cutaneous vascular arteriovenous fistulas can occur (Wooderchak-Donahue et al.). This case highlights the importance of clarifying a family history, classifying vascular birthmarks and working with the multidisciplinary team. Genetic testing should be considered, even with previous negative analysis, as test sensitivity has improved and will now include analysis of EPHB4, which has also been associated with CM–AVM.

Spinal Pial Arteriovenous Fistulas: Angioarchitecture and Management

Spinal pial arteriovenous fistulas (spAVFs) are rare, high-flow vascular malformations consisting of a single dilated pial artery connecting directly to an enlarged draining vein. This article describes the anatomic, clinical, and diagnostic features of spAVFs, to help clinicians to select the best treatment option. Both surgical and endovascular treatments are effective; microsurgery has a higher success rate. To maximize the exclusion rate, a multidisciplinary approach and adequate preoperative study are mandatory.

Intraosseous resection of mandibular arteriovenous malformations: A mandible sparing multi-disciplinary case series

Mandibular arteriovenous malformations (AVMs) are high flow vascular malformations that can cause pain, hypertrophy, deformity, malocclusion, jaw asymmetry, bone destruction, tooth loss, and severe bleeding [1]. Although general principles apply, the rarity of mandibular AVMs limits definitive agreement on the best course of treatment. Current treatment options include embolization, sclerotherapy, surgical resection, or some combination of techniques [2]. [3]. An alternative multidisciplinary technique of embolization with mandibular-sparing resection is presented. This technique aims to mitigate bleeding with effective removal of the AVM, while preserving mandibular form, function, dentition, and occlusion.

NOTCH4 Single-Nucleotide Polymorphism Is Associated with Brain Arteriovenous Malformation in a Chinese Han Population

Introduction: Brain arteriovenous malformations (BAVMs) are high-flow intracranial vascular malformations characterized by the direct connection of arteries to veins without an intervening capillary bed. They are one of the main causes of intracranial hemorrhage and epilepsy, although morbidity is low. Angiogenesis, heredity, inflammation, and arteriovenous malformation syndromes play important roles in BAVM formation. Animal experiments and previous studies have confirmed that NOTCH4 may be associated with BAVM development. Our study identifies a connection between NOTCH4 gene polymorphisms and BAVM in a Chinese Han population. Methods: We enrolled 150 patients with BAVMs confirmed by digital subtraction angiography (DSA) in the Department of Neurosurgery, Zhujiang Hospital, Southern Medical University from June 2017 to July 2019. Simultaneously, 150 patients without cerebrovascular disease were confirmed by computed tomography angiography/magnetic resonance angiography/DSA. DNA was extracted from peripheral blood and NOTCH4 genotypes were identified by PCR-ligase detection reaction. The χ² test or Fisher’s exact test was used to evaluate the differences in allele and genotype frequencies between the BAVM group, control group, bleeding group, and other complications. Results: Two single-nucleotide polymorphisms (SNPs), rs443198 and rs438475, were significantly associated with BAVM. No SNP genotypes were significantly associated with hemorrhage or epilepsy. SNPs rs443198_AA-SNP and rs438475_AA-SNP may be associated with a lower risk of BAVM (p = 0.011, odds ratio (OR) = 0.459, 95% confidence interval (CI): 0.250–0.845; p = 0.033, OR = 0.759, 95% CI: 0.479–1.204). Conclusion: NOTCH4 gene polymorphisms were associated with BAVM and may be a risk factor in a Chinese Han population.

Early follow-up quality of life and mental health of patients with congenital vascular malformations cared for in a multi-disciplinary specialist centre.

The study aimed to evaluate the early follow-up quality of life (QoL), pain and mental health of patients with congenital vascular malformation (CVM) from a variety of treatment options. All patients with CVM who received care and had follow-up between February 1st 2018 and January 31st 2020 were included. The health-related QoL, pain, and mental health were assessed with RAND Health Care 36-Item Short Form Survey (SF-36), visual analogue score for pain (VAS-P) and Hospital Anxiety and Depression Scale (HADS). Paired t-test was used for all analyses. p < .05 were considered significant. In total, 110 patients with a mean age of 36.9 years were included in this study. In all patients following care, significant improvement was found in the bodily pain domain of SF-36 and VAS-P (both p = .01). This was largely driven by high-flow vascular malformation patients who responded better to embolo-sclerotherapy, which revealed significant improvement in the bodily pain domain of SF-36 (p = .002) and VAS-P (p = .02). Patients who received supportive treatment only reported significant improvement in mental health (p = .004) and social functioning (p = .03) domains of SF-36. Meanwhile, patients treated with embolo-sclerotherapy reported significant improvement only in VAS-P (p = .02). This study concluded that the effects of care on early follow-up QoL, pain and mental health of patients with CVM were heterogenous. Future research should therefore, include larger sample size and longer term follow-up to understand the various factors that affect the QoL and mental health of these patients, as well as the holistic approaches to manage them.

Combining superselective catheterization and electrochemotherapy: A new technological approach to the treatment of high-flow head and neck vascular malformations.

The study aims to demonstrate a combination of superselective catheterization and electrochemotherapy as a feasible and effective new technological approach in treating high-flow vascular malformations of the head and neck region. In the patient with high-flow arteriovenous malformation of the lower lip, superselective catheterization was performed under general anesthesia. The microcatheter was used to administer 750 IU BLM intra-arterially into the feeding vessel. The whole malformation surface was then covered with 15 applications of electric pulses using the plate electrode. Excellent response, without functional or aesthetic deficits, was obtained in 10 weeks. During this period, debridement and necrectomy were performed regularly on follow-up visits. The pain was managed with oral paracetamol and sodium metamizole. Combining electrochemotherapy using bleomycin with superselective catheterization and arteriography is a feasible treatment option for high-flow vascular malformations in the head and neck region and could play a significant role in managing these challenging lesions.

Reconstruction after ablative treatment of arteriovenous malformations of the head and neck.

Arteriovenous malformations are high-flow congenital vascular malformations that are characterized by abnormal connections between arteries and veins across an abnormal capillary bed. The head and neck region is the most common location for extracranial arteriovenous malformations. Due to their highly invasive, aggressive, and locally destructive nature, arteriovenous malformations are difficult to treat, and management through a multimodal, multidisciplinary approach is recommended. The mainstay of treatment is embolization and surgical excision. With the advent of genetic research, adjuvant targeted medical therapy is starting to play a larger role. Successful surgical treatment with or without embolization requires removal of the nidus. Large, focal, or diffuse lesions involving multiple anatomic areas usually necessitates surgical reconstruction. Free tissue transfer has many advantages over more conservative methods with restoration of function and contour. Herein, the authors describe the surgical treatment and reconstruction in head and neck arteriovenous malformations.

A study of duplex ultrasound examination in peripheral vascular malformations

Vascular malformations belong to wide spectrum of disease involving all vascular segments- arteries, veins as well as lymphatics. Being Ultrasound as the primary diagnostic modality, all peripheral vascular malformation diagnosis can be made by clinical examination and duplex ultrasound examination.A study of 50 patients was carried over a period of 1 year from 1 May 2021 to 1 May 2022 on the patient who came with complain of slow growing, superficial swelling which is painless in nature. The machine used is Affinity Philips 70 G.With help of duplex ultrasound, various types of vascular malformations were diagnosed with incidence such as Slow Flow Venous malformation (60%- 30 patients), High flow Arterio-venous malformations (16%- 8 patients), Capillary malformations (12%- 6 patients) and Lymphatic malformations (12%- 6 patients).Vascular malformations have been classified into venous, arterial, capillary, combined and lymphatic malformations types. Besides age presentations, detailed history and clinical examination, ultra-sound imaging plays an important role in correct diagnosis and classification of vascular malformations. It assesses exact flow dynamics in order to differentiate between Slow flow v/s High flow vascular malformations. MRI is most valuable diagnostic tool for comprehensive assessment of vascular malformationsUltrasound are first imaging modality in peripheral vascular malformations. It has plays crucial role in proper treatment planning of the lesion as it describes the extent, type, flow pattern within the lesion.

Clinical and Radiological Correlation of Low Flow Vascular Malformation Treated With Percutaneous Sclerotherapy.

Objective: To retrospectively correlate imaging findings post-sclerotherapy of low-flow vascular malformations with clinical outcome. Materials and Methods: We retrospectively evaluated 81 pediatric patients who had sclerotherapy in our department over a 14-year period. Patients with a diagnosis of low-flow vascular malformation, pre and post-treatment ultrasound (US) and clinical follow-up evaluation were included in the study. Exclusion criteria were coexisting high-flow vascular malformations, history of additional surgical or medical treatment to their malformation and large infiltrative lesions difficult to measure on US. Pre and post-treatment sonographic volumes of the malformation were assessed. Changes in volume were categorized into 6- increased volume, stable and volume decrease of 1-25%/26-50%/51-75%/75-100%. Clinical outcomes were categorized into 4 - worse, no change, improved and symptom free. In cases where pre-treatment MRI was available, the estimated malformation volumes in both modalities were correlated using Spearman's rank correlation. The change in sonographic volume was correlated with clinical outcome using Spearman's rank correlation. P-values < .05 were considered significant. Results: Twenty-nine patients were included in the study; 13 with venous malformation (VM), and 16 with lymphatic malformation (LM). Nineteen patients had both pre-treatment US and MRI, showing correlation in volume between the 2 modalities (P < .001). Post-treatment change in volume correlated with clinical outcome for combined venous and LMs (rho = .44, P = .02). No correlation was found when venous (rho = .48, P = .09) and lymphatic (rho = .33, P = .21) malformations were considered separately. Conclusion: Ultrasound can potentially be used as an objective tool in evaluating sclerotherapy treatment response of low-flow vascular malformations in the pediatric population.

Endovascular Management of Brain Arteriovenous Malformation (AVM) Presenting with Contralateral Morbid Tinnitus: A Case Report

Brain arteriovenous malformations are type of intracranial high-flow vascular malformation that can present with incidental finding in asymptomatic patients, seizures, headache, ischemic events due to vascular steal from normal brain, hemorrhage. Pulsatile tinnitus is the result of blood flow related sounds transmitted to the inner ear and coincides with heartbeat. AVMs are a rare cause of pulsatile tinnitus which contributes to less than 1% of published cases in the literature. We report a case of morbid tinnitus due to brain AVM which was resolved completely by endovascular embolization of the lesion. J Bangladesh Coll Phys Surg 2022; 40: 128-131

Somatic activating BRAF variants cause isolated lymphatic malformations.

SummarySomatic activating variants in PIK3CA, the gene that encodes the p110α catalytic subunit of phosphatidylinositol 3-kinase (PI3K), have been previously detected in ∼80% of lymphatic malformations (LMs).1,2 We report the presence of somatic activating variants in BRAF in individuals with LMs that do not possess pathogenic PIK3CA variants. The BRAF substitution p.Val600Glu (c.1799T>A), one of the most common driver mutations in cancer, was detected in multiple individuals with LMs. Histology revealed abnormal lymphatic channels with immunopositivity for BRAFV600E in endothelial cells that was otherwise indistinguishable from PIK3CA-positive LM. The finding that BRAF variants contribute to low-flow LMs increases the complexity of prior models associating low-flow vascular malformations (LM and venous malformations) with mutations in the PI3K-AKT-MTOR and high-flow vascular malformations (arteriovenous malformations) with mutations in the RAS-mitogen-activated protein kinase (MAPK) pathway.3 In addition, this work highlights the importance of genetic diagnosis prior to initiating medical therapy as more studies examine therapeutics for individuals with vascular malformations.

Hydrocephalus in Vein of Galen Malformations.

Vein of Galen malformation (VOGM) is a fistulous arteriovenous malformation presenting in the early childhood. Hydrocephalus with VOGM develops in one half of patients during the course of the disease. The concept of hydrodynamic disorders is the key to understand the development of hydrocephalus. VOGM results in venous hypertension that secondarily disturbs cerebrospinal fluid (CSF) absorption leading to hydrocephalus and occurs frequently in infants and young children. The medullary veins are thought to be the main pathway for absorption of CSF by the cerebrofugal gradient act as the driving force. In neonates, the cavernous sinus is poorly developed and brain does not use it for venous drainage along with poor jugular bulb maturation results in poor venous drainage reserve. The presence of high flow vascular malformation with poor venous drainage reserve leads to hydrodynamic disorder, poor CSF absorption, and hydrocephalus. Apart from this, hydrocephalus secondary to intraventricular hemorrhage and physical obstruction of the enlarged VOGM at the aqueduct has been proposed. The management strategy is to perform timely endovascular treatment to correct the hydrodynamic disorder and avoid ventricular shunting. Trans-arterial embolization is the effective way, as it decreases flow in the malformation, secondarily the venous hypertension, and thereby improving the clinical symptoms related to hydrodynamic disorder. Ventricular diversion procedure is indicated in symptomatic hydrocephalus after exhausting our effort to reduce hydrodynamic pressure by endovascular embolization.

The cerebrofacial metameric syndromes: An embryological review and proposal of a novel classification scheme.

The cerebrofacial metameric syndromes are a group of congenital syndromes that result in vascular malformations throughout specific anatomical distributions of the brain, cranium and face. Multiple reports of patients with high-flow or low-flow vascular malformations following a metameric distribution have supported this idea. There has been much advancement in understanding of segmental organization and cell migration since the concept of metameric vascular syndromes was first proposed. We aim to give an updated review of these embryological considerations and then propose a more detailed classification system for these syndromes, predominately incorporating the contribution of neural crest cells and somitomeres to the pharyngeal arches.