Venous malformations

Recent advances in nanomaterial-driven strategies for diagnosis and therapy of vascular anomalies

Nanotechnology has demonstrated immense potential in various fields, especially in biomedical field. Among these domains, the development of nanotechnology for diagnosing and treating vascular anomalies has garnered significant attention. Vascular anomalies refer to structural and functional anomalies within the vascular system, which can result in conditions such as vascular malformations and tumors. These anomalies can significantly impact the quality of life of patients and pose significant health concerns. Nanoscale contrast agents have been developed for targeted imaging of blood vessels, enabling more precise identification and characterization of vascular anomalies. These contrast agents can be designed to bind specifically to abnormal blood vessels, providing healthcare professionals with a clearer view of the affected areas. More importantly, nanotechnology also offers promising solutions for targeted therapeutic interventions. Nanoparticles can be engineered to deliver drugs directly to the site of vascular anomalies, maximizing therapeutic effects while minimizing side effects on healthy tissues. Meanwhile, by incorporating functional components into nanoparticles, such as photosensitizers, nanotechnology enables innovative treatment modalities such as photothermal therapy and photodynamic therapy. This review focuses on the applications and potential of nanotechnology in the imaging and therapy of vascular anomalies, as well as discusses the present challenges and future directions.

Anticoagulation and vascular anomalies

A State of the Art lecture titled "Anticoagulation and Vascular Anomalies" was presented at the International Society on Thrombosis and Haemostasis (ISTH) Congress in 2023. Vascular anomalies have been classified by the International Society for the Study of Vascular Anomalies into vascular tumors and vascular malformations. Although some vascular tumors, such as tufted angioma and kaposiform hemangioendothelioma, and other vascular malformations can present with coagulation aberrancies, these are not generally managed with anticoagulation. A subclassification of vascular malformations includes slow-flow vascular malformations. It is this subgroup specifically that has a high risk of venous thromboembolism (VTE) and morbidity associated with coagulopathy that may be present. In these select cases, anticoagulation may be indicated to reduce the risk of VTE, treat VTE, or manage localized thrombosis in the malformation that causes significant pain and reduced quality of life. There are established risk factors for VTE in these patients that will be reviewed. Finally, we summarize relevant new data on this topic presented during the 2023 ISTH Congress.

Management of congenital urogenital and perineal vascular malformations: correlation of clinical findings with diagnostic imaging for treatment decision

PURPOSE

 Analysis of clinical and diagnostic findings in rare urogenital and perineal vascular malformations only occurring in 2-3 % of vascular anomalies with regard to clinical symptoms and treatment decisions.

MATERIALS AND METHODS

 All 25 out of 537 patients presenting with congenital urogenital and perineal vascular malformations at our institution from 2014 to 2021 were included. Vascular anomaly classification, anatomical location, clinical symptoms at presentation, diagnostic imaging, and pain intensity were retrospectively assessed from the patient record and therapy management was evaluated.

RESULTS

 In total, 25 patients (10 females (40 %), 15 males (60 %)), aged 6 to 77 years were included. Diagnoses were: 10 (40 %) venous malformations (VMs), 5 (20 %) lymphatic malformations (LMs) and 10 (40 %) arteriovenous malformations (AVMs). Malformation manifestations were: 12 (32 %) lesser pelvis, 12 (32 %) external genitalia, and 13 (34 %) perineal/gluteal region. One AVM was located in the kidney. The leading clinical symptom was pain. The mean intensity was 6.0/10 for LM, 5.7/10 for VM, and 4.5/10 for AVM. Further major symptoms included physical impairment, local swelling, and skin discoloration. Bleeding complications or sexual dysfunction were rare findings. Patients with VM reported significantly more symptoms than patients with AVM (p = 0.0129). In 13 patients (52 %) minimally invasive therapy was indicated: 10 (77 %) sclerotherapies and 3 (23 %) transcatheter embolization procedures. Complete symptomatic remission was achieved in 9 (69 %) patients, partial response in 3 (23 %) patients, and 1 patient showed no clinical response to therapy. Follow-up appointments without the need for immediate minimally invasive therapy were significantly more common in patients with AVMs than in patients with VMs (p = 0.0198).

CONCLUSION

 To create a higher awareness of congenital urogenital and perineal vascular malformations. Awareness of this rare condition avoids misdiagnosis. Therapy decisions should be symptom-oriented. Emergency intervention is rarely required, even in fast-flow vascular malformations.

KEY POINTS

  · Venous malformations cause more symptoms with higher pain intensity than arteriovenous malformations.. · Diagnosis and adequate treatment can be hampered by a lack of awareness of the clinical presentation.. · Bleeding complications are rare, even in high-flow vascular malformations.. · Pain and physical impairment are the most commonly observed symptoms in these patients..

Approach to clinically significant vascular anomalies in children

Vascular anomalies consist of tumours or malformations made up of abnormal growth or collections of blood vessels that can result in functional or cosmetic problems. While many vascular anomalies are present at birth, some do not appear until later in life, making diagnosis more challenging. Although many vascular anomalies are benign, some are associated with serious complications and may involve multiple organ systems. This article highlights the important features of clinically significant vascular anomalies to help physicians promptly identify and refer these cases to a specialised multidisciplinary team for evaluation and management. The discussion includes the various presenting complaints of vascular anomalies in children, namely, rapidly growing birthmarks, painful lesions, seizures/neurological manifestations, bleeding diathesis, cardiac/airway abnormalities and part of an overgrowth syndrome.

A nationwide cohort study on incidence and mortality associated with extracranial vascular malformations

Extracranial vascular malformations are abnormal formations of blood vessels located outside the brain (extracranial) that develop during fetal development. They are caused by errors in the formation of blood vessels in the embryo and can affect various parts of the body, such as the head, neck, face, and other regions. Some malformations may be asymptomatic and only require monitoring, while others may cause significant health issues or cosmetic concerns and may need medical intervention. There are very few studies have investigated the nationwide incidence and quantitative mortality of vascular malformations in terms of their subtypes. Thus, this study aimed to determine the nationwide incidence and mortality associated with vascular malformations. This nationwide population-based study evaluated 70,517 patients with vascular malformations from 2008 to 2021. We evaluated the incidence and mortality associated with each subtype of vascular malformation. Furthermore, Cox regression analysis was used to evaluate the association between vascular malformation and mortality. The annual incidence (per 100,000 population) of overall vascular, venous, capillary, arteriovenous, and lymphatic malformations was 9.85, 1.48, 2.31, 0.24, and 5.82 cases, respectively. Patients with vascular malformations, except those with venous malformations, had higher mortality than the matched controls. Moreover, among the vascular malformation subgroups, the adjusted hazard ratio of mortality was the highest for arteriovenous malformations. This study revealed that the overall annual incidence of vascular malformations was 9.85 cases per 100,000 population in Korea from 2008 to 2021. The mortality of the matched general population was lower than that of patients with vascular malformations, except for those with venous malformations. Additionally, the adjusted hazard ratio for mortality associated with arteriovenous malformations was the highest among the vascular malformation subgroups.

Role of UDP-glucose ceramide glucosyltransferase in venous malformation

Venous malformation (VM) results from the abnormal growth of the vasculature; however, the detailed molecular mechanism remains unclear. As a glycosyltransferase, UDP-glucose ceramide glucosyltransferase (UGCG) is localized to the Golgi body and is a key enzyme in the first step of glycosphingolipid synthesis. Here, we aimed to explore the relationship between UGCG and the development of VM. First, investigations using RT-qPCR and Western blotting on the diseased vasculature of VM patients and normal vascular tissues revealed that UGCG expression was markedly elevated in the diseased vessels. Subsequently, immunofluorescence assay showed that UGCG was co-localized with CD31, an endothelial cell marker, in tissues from patients with VM and healthy subjects. Then, we established TIE2-L914F-mutant human umbilical vein endothelial cells (HUVECs) by lentivirus transfection. Next, Western blotting revealed that UGCG expression was considerably higher in HUVECs^TIE2-L914F. In addition, we established a UGCG-overexpressing HUVECs line by plasmid transfection. With the CCK8 cell proliferation experiment, wound healing assay, and tube formation assay, we found that UGCG could promote the proliferation, migration, and tube formation activity of HUVECs, whereas the inhibition of UGCG could inhibit the proliferation, migration, and tube formation activity of HUVECs^TIE2-L914F. Finally, Western blotting revealed that UGCG regulates the AKT/mTOR pathway in HUVECs. These data demonstrated that UGCG can affect the activity of vascular endothelial cells and regulate the AKT/mTOR signaling pathway; this is a potential mechanism underlying VM pathogenesis.

Pediatric Interventional Neuroradiology: Opportunities and Challenges

Pediatric interventional neuroradiology (PINR) is a relatively new field of diagnostic and therapeutic care in the pediatric population that has seen considerable advances in recent decades. However, it is still lagging behind adult interventional neuroradiology due to a variety of reasons, including the lack of evidence validating pediatric-specific procedures, the relative absence of pediatric-specific equipment, and the challenges in establishing and maintaining PINR competencies in a relatively small number of cases. Despite these challenges, the number and variety of PINR procedures are expanding for a variety of indications, including unique pediatric conditions, and are associated with reduced morbidity and psychological stigma. Continued technological advances, such as improved catheter and microwire designs and novel embolic agents, are also contributing to the growth of the field. This review aims to increase awareness of PINR and provide an overview of the current evidence base for minimally invasive neurological interventions in children. Important considerations, such as sedation, contrast agent use, and radiation protection, will also be discussed, taking into account the distinct characteristics of the pediatric population. The review highlights the usefulness and benefits of PINR and emphasizes the need for ongoing research and development to further advance this field.

Venous malformations: what do phleboliths tell us in the pediatric population?

PURPOSE

Phleboliths are often observed within Venous malformations (VM) and frequently indicated as cause of morbidity. The aim of this study is to investigate independent risk factors for phleboliths in a pediatric population and to determine if its presence influences clinical management.

METHODS

We retrospectively review data from patients diagnosed with VM in a vascular anomalies center during a 5-year period. Associations between phleboliths and potential risk factors were assessed. A multivariable analysis, was performed to assess the influence of phleboliths in the need for surgery.

RESULTS

We included 88 patients with a mean age of 10 years. Phleboliths were found in 33.0%. In univariate analysis, there were no significant differences between the two groups regarding age or gender, location, dimension or depth of the VM, pain and laboratory parameters. Multivariable analysis could not detect any independent risk factor for phleboliths. In contrast, multivariable logistic analysis revealed that when phleboliths were present, the need for surgical extirpation was more likely (p = 0.031).

CONCLUSIONS

This study showed that patients who have phleboliths within their VM seem to require surgery more frequently. This constitutes an entirely innovative thought that could raise awareness to a lower threshold for surgery in this group of patients.

Thoracic venous malformation: a particular form of a visceral variant

A teenage boy was admitted due to a thoracic mass with previous respiratory infections. The CT scan showed phleboliths in a cystic lesion with large draining channels. He also presented a mild thrombocytosis, elevated fibrinogen and D-dimer. Arteriogram revealed no abnormal arterial supply but venography proved venous draining channels as the major components of the lesion. The most important venous pedicle was embolised. However, 6 months later, CT scan showed no reduction in lesion size. Surgical resection was performed. Anatomopathological study described a venous malformation (VM) with a lymphatic component, and genetic testing found a typical mutation in PIK3CA and genetic variant in MAP3K3 This case reports a very rare pattern of thoracic vascular tumour. The authors aim to highlight the importance of genetic studies of VM with atypical presentation in order to achieve a definitive diagnosis.

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.

Venous malformations

The often inexorable growth and expansion of congenital vascular malformations can result in substantial morbidity and, in some cases, premature death of these patients. Despite this, patients suffering from such lesions are often erroneously diagnosed and/or inadequately treated, due to a lack of expertise among primary care practitioners as well as specialists. Venous malformations are the most common type of congenital vascular malformations. Over the last two decades management of these lesions has significantly improved, predominantly due to the introduction and implementation of multidisciplinary team concept as well as improvement in diagnostic and treatment modalities. Relatively recently genetic studies are providing more insights into underlying pathophysiological mechanisms responsible for the development and progression of venous malformations and pharmacotherapy is becoming extensively evaluated for safety and efficacy in the treatment of these often challenging vascular lesions.

Management of Venous Malformations

Venous malformations (VMs) are slow-flow, congenital vascular anomalies that are a result of vascular dysgenesis. Clinical presentation and morbidity depend on size, location, and association with other syndromes. VMs are the most common symptomatic vascular anomaly referred for intervention, usually due to thrombosis, swelling, mass effect, functional compromise, or cosmetic concerns. Treatment for larger lesions can be challenging and a multidisciplinary approach involving medical, interventional, and surgical input is critical for comprehensive care. This article will assist the interventional radiologist in patient assessment and will discuss current techniques for treatment, means to minimize adverse events, and expected outcomes.