Venous malformation: update on aetiopathogenesis, diagnosis and management

Diagnostic approach to hepatic vascular lesions: a paediatric perspective

The pathological evaluation of hepatic vascular lesions in children requires special consideration. Inconsistent terminology, rarity of pathology specimens and overlapping pathological features between various lesions may pose a serious diagnostic challenge. In this review, we highlight the importance of using the International Society for the Study of Vascular Anomalies (ISSVA) classification scheme to characterise these lesions. Selected entities are discussed, including hepatic vascular tumours exclusively seen in the paediatric age group, hepatic infantile haemangioma and hepatic congenital haemangioma. Vascular malformations, with emphasis on their syndromic associations (venous malformation in blue rubber bleb naevus syndrome) and complications (hepatocellular nodules in Abernethy malformation) are also covered.

Targeted therapy for capillary-venous malformations

Sporadic venous malformations are genetic conditions primarily caused by somatic gain-of-function mutation of PIK3CA or TEK, an endothelial transmembrane receptor signaling through PIK3CA. Venous malformations are associated with pain, bleedings, thrombosis, pulmonary embolism, esthetic deformities and, in severe cases, life-threatening situations. No authorized medical treatment exists for patients with venous malformations. Here, we created a genetic mouse model of PIK3CA-related capillary venous malformations that replicates patient phenotypes. We showed that these malformations only partially signal through AKT proteins. We compared the efficacy of different drugs, including rapamycin, a mTORC1 inhibitor, miransertib, an AKT inhibitor and alpelisib, a PI3Kα inhibitor at improving the lesions seen in the mouse model. We demonstrated the effectiveness of alpelisib in preventing vascular malformations' occurrence, improving the already established ones, and prolonging survival. Considering these findings, we were authorized to treat 25 patients with alpelisib, including 7 children displaying PIK3CA (n = 16) or TEK (n = 9)-related capillary venous malformations resistant to usual therapies including sirolimus, debulking surgical procedures or percutaneous sclerotherapies. We assessed the volume of vascular malformations using magnetic resonance imaging (MRI) for each patient. Alpelisib demonstrated improvement in all 25 patients. Vascular malformations previously considered intractable were reduced and clinical symptoms were attenuated. MRI showed a decrease of 33.4% and 27.8% in the median volume of PIK3CA and TEK malformations respectively, over 6 months on alpelisib. In conclusion, this study supports PI3Kα inhibition as a promising therapeutic strategy in patients with PIK3CA or TEK-related capillary venous malformations.

Vascular Malformations

Vascular malformations are intricate anomalies of the circulatory system, presenting a diverse array of clinical manifestations, and posing significant challenges in diagnosis and treatment. The pathogenesis of vascular malformations is explored through the lens of genetic and molecular mechanisms, shedding light on the pivotal role of somatic mutations and dysregulated signaling pathways. Clinical presentations of vascular malformations are widely variable, ranging from cosmetic concerns to life-threatening complications. The utility of imaging techniques, such as magnetic resonance imaging (MRI), computed tomography (CT), and angiography, are discussed in detail, emphasizing their role in precise delineation and characterization. Therapeutic strategies for vascular malformations are multifaceted, considering factors such as lesion size, location, potential complications, and patient-specific factors. Traditional interventions, including surgical excision and embolization, are appraised alongside emerging approaches like targeted molecular therapies and minimally invasive procedures. The manuscript underscores the need for an individualized treatment approach, optimizing outcomes while minimizing risks and complications. In summation, this manuscript offers a comprehensive analysis of vascular malformations, encompassing their underlying pathogenesis, clinical nuances, diagnostic methods, and therapeutic considerations. By synthesizing current knowledge and highlighting gaps in understanding, this review serves as a valuable resource for clinicians, researchers, and medical practitioners, fostering an enhanced comprehension of vascular malformations and paving the way for improved patient care and innovative research endeavors.

Whole-lesion assessment of volume and signal changes after sclerotherapy of extremity venous malformations

PURPOSE

To investigate quantitative changes in MRI signal intensity (SI) and lesion volume that indicate treatment response and correlate these changes with clinical outcomes after percutaneous sclerotherapy (PS) of extremity venous malformations (VMs).

METHODS

VMs were segmented manually on pre- and post-treatment T2-weighted MRI using 3D Slicer to assess changes in lesion volume and SI. Clinical outcomes were scored on a 7-point Likert scale according to patient perception of symptom improvement; treatment response (success or failure) was determined accordingly.

RESULTS

Eighty-one patients with VMs underwent 125 PS sessions. Treatment success occurred in 77 patients (95 %). Mean (±SD) changes were -7.9 ± 24 cm3 in lesion volume and -123 ± 162 in SI (both, P <.001). Mean reduction in lesion volume was greater in the success group (-9.4 ± 24 cm3) than in the failure group (21 ± 20 cm3) (P =.006). Overall, lesion volume correlated with treatment response (ρ = -0.3, P =.004). On subgroup analysis, volume change correlated with clinical outcomes in children (ρ = -0.3, P =.03), in sodium tetradecyl sulfate-treated lesions (ρ = -0.5, P =.02), and in foot lesions (ρ = -0.6, P =.04). SI change correlated with clinical outcomes in VMs treated in 1 PS session (ρ = -0.3, P =.01) and in bleomycin-treated lesions (ρ = -0.4, P =.04).

CONCLUSIONS

Change in lesion volume is a reliable indicator of treatment response. Lesion volume and SI correlate with clinical outcomes in specific subgroups.

Transoral Robotic Surgery for a Rare Case of Venolymphatic Malformation in Parapharyngeal Space

Venous malformations are low flow endothelial malformations with aberrant and ectatic venous channels. They are defects in vascular growth which causes functional and cosmetic impairment. Gradual growth in size of the lesion occurs due to venous congestion or thrombosis. Venous malformations in parapharyngeal space are a rare entity and are difficult to diagnose. Case Report. 13 year old boy presented with a history of hyposmia and progressive difficulty in breathing for a duration of 2.5 years. MRI face and neck with contrast showed a 4.5 × 4.3x3.6 cm lesion in the left parapharyngeal space. CT angiogram of brain and neck demonstrated a heterogeneously enhancing mass in the left parapharyngeal region. PET scan illustrated an ill-defined mass in the left pre styloid parapharyngeal space. Biopsy from the lesion showed features consistent with venolymphatic malformation. Flexible laryngoscopy showed a bulge over the left soft palate region with narrowing of nasopharyngeal lumen. Patient underwent transoral robotic surgery for complete excision of the mass. Post-operative period was uneventful. He has been on follow up for the past 1 year with no evidence of any residual or recurrent disease. Venolymphatic malformation is a rare lesion in the parapharyngeal space which is difficult to diagnose pre operatively. Surgical excision is the preferred modality of treatment for deep seated lesions in the parapharyngeal space. The advent of transoral robotic surgery have reduced the morbidity and improved clearance for such cases.

p-AKT/VPS4B regulates the small extracellular vesicle size in venous malformation endothelial cells

OBJECTIVE

Small extracellular vesicle (sEV)-mediated intercellular communication is increasingly the key for the understanding of venous malformations (VMs). This study aims to clarify the detailed changes of sEVs in VMs.

SUBJECTS AND METHODS

Fifteen VM patients without treatment history and twelve healthy donors were enrolled in the study. sEVs were isolated from both fresh lesions and cell supernatant, and were examined by western blotting, nanoparticle tracking analysis and transmission electron microscopy. Western blot analysis, immunohistochemistry and immunofluorescence were adopted to screening candidate regulator of sEV size. Specific inhibitors and siRNA were employed to validate the role of dysregulated p-AKT/vacuolar protein sorting-associated protein 4B (VPS4B) signaling on the size of sEVs in endothelial cells.

RESULTS

The size of sEVs derived from both VM lesion tissues and cell model was significantly increased. VPS4B, whose expression level was mostly significantly downregulated in VM endothelial cells, was responsible for the size change of sEVs. Targeting abnormal AKT activation corrected the size change of sEVs by recovering the expression level of VPS4B.

CONCLUSION

Downregulated VPS4B in endothelial cells, resulted from abnormally activated AKT signaling, contributed to the increased size of sEVs in VMs.

Direct oral anticoagulants and venous malformations: literature review and retrospective study of 29 patients

Background

Venous malformations (VMs) are commonly associated with localized intravascular coagulopathy leading to elevated D-dimer and risks of hemorrhagic and thromboembolic events, particularly in extensive lesions. While low-molecular-weight heparin (LMWH) has been effective in managing coagulopathy and pain, direct oral anticoagulants (DOACs) emerge as a promising alternative.

Objectives

This study aims to evaluate the efficacy and safety of DOACs in treating VMs associated with localized intravascular coagulopathy, offering a comparative perspective to LMWH.

Methods

A retrospective study was conducted on 29 patients with VMs and secondary localized intravascular coagulopathy treated with DOACs between 2013 and 2023 in a single tertiary center specialized in vascular anomalies. Data were collected from February 24, 2023, to September 1, 2023.

Results

Patients' median age was 40 years (range, 22-76 years), with a female predominance of 66%. Descriptive statistical analysis showed that 85% of patients experienced pain improvement, and 86% showed a reduction in D-dimer by at least 25%, with a mean reduction of 57% (SD, ±32%; IQR, [38-81%]). Additionally, 37% of patients reported a bleeding event, mostly minor.

Conclusion

The study findings suggests that DOACs may serve as an alternative to LMWH for patients with VMs associated with pain management and reduced D-dimer, alongside a low observed risk of major bleeding. Tailored dosing considering the location of the malformation, bleeding and thrombotic tendencies, and laboratory abnormalities is recommended. Future studies with larger cohorts and extended follow-up are necessary for more conclusive evidence on DOACs' role in this patient population.

Comprehensive phenotypic and genomic characterization of venous malformations

Venous malformations (VMs) are the most common vascular malformations. TEK and PIK3CA are the causal genes of VMs, and may be involved in the PI3K/AKT pathway. However, the downstream mechanisms underlying the TEK or PIK3CA mutations in VMs are not completely understood. This study aimed to identify a possible association between genetic mutations and clinicopathological features. A retrospective clinical, pathological, and genetic study of 114 patients with VMs was performed. TEK, PIK3CA, and combined TEK/PIK3CA mutations were identified in 49 (43%), 13 (11.4%), and 2 (1.75%) patients, respectively. TEK-mutant VMs more commonly occurred in younger patients than TEK and PIK3CA mutation-negative VMs (other-mutant VMs), and showed more frequent skin involvement and no lymphocytic aggregates. No significant differences were observed in sex, location of occurrence, malformed vessel size, vessel density, or thickness of the vascular smooth muscle among the VM genotypes. Immunohistochemical analysis revealed that the expression levels of phosphorylated AKT (p-AKT) were higher in the TEK-mutant VMs than those in PIK3CA-mutant and other-mutant VMs. The expression levels of p-mTOR and its downstream effectors were higher in all the VM genotypes than those in normal vessels. Spatial transcriptomics revealed that the genes involved in "blood vessel development", "positive regulation of cell migration", and "extracellular matrix organization" were up-regulated in a TEK-mutant VM. Significant genotype-phenotype correlations in clinical and pathological features were observed among the VM genotypes, indicating gene-specific effects. Detailed analysis of gene-specific effects in VMs may offer insights into the underlying molecular pathways and implications for targeted therapies.

Whole mount of adult ear skin as a model to study vascular malformations

BACKGROUND

Genetic analysis in human patients has linked mutations in PIK3CA, the catalytic subunit of PI-3'Kinase, to sporadic incidences of vascular malformations.

METHODS

We have developed a mouse model with inducible and endothelial-specific expression of PIK3CAH1047R , resulting in the development of vascular malformations. Systemic induction of this mutation in adult mice results in rapid lethality, limiting our ability to track and study these lesions; therefore, we developed a topical and local induction protocol using the active metabolite of tamoxifen, 4OH-T, on the ear skin of adults.

RESULTS

This approach allows us to successfully model the human disease in a mature and established vascular bed and track the development of vascular malformations. To validate the utility of this model, we applied a topical rapamycin ointment, as rapamycin is therapeutically beneficial to patients in clinical trials. We found that the induced ear lesions showed significant attenuation after treatment, which was easily quantified.

CONCLUSIONS

These data collectively provide evidence of a new model to study vascular malformations in adult tissues, which should be particularly useful in environments lacking specialized small-animal imaging facilities.

Outcome after surgical treatment of venous malformations of the hand in childhood

OBJECTIVE

Surgical treatment of venous malformations (VMs) of the hand is challenging. The hand's small functional units, dense innervation, and terminal vasculature can be easily compromised during invasive interventions like surgery or sclerotherapy, leading to an increased risk of functional impairment, cosmetic consequences, and negative psychological effects.

METHODS

We have conducted a retrospective review of all surgically treated patients diagnosed with VMs of the hand between 2000 and 2019 and evaluated their symptoms, diagnostic investigations, complications, and recurrences.

RESULTS

Twenty-nine patients (females, n = 15) with a median age of 9.9 years (range, 0.6-18 years) were included. Eleven patients presented with VMs involving at least one of the fingers. In 16 patients, the palm and/or dorsum of the hand was affected. Two children presented with multifocal lesions. All patients presented with swelling. Preoperative imaging was done in 26 patients and consisted of magnetic resonance imaging in nine patients, ultrasound in eight patients, and both modalities in nine patients. Three patients underwent surgical resection of the lesions without any imaging. Indications for surgery were pain and restriction of function (n = 16), and when lesions were preoperatively evaluated as completely resectable (n = 11). In 17 patients, a complete surgical resection of the VMs was performed, whereas in 12 children, an incomplete resection of VM was deemed due to nerve sheath infiltration. At a median follow-up of 135 months (interquartile range, 136.5 months; range, 36-253 months), recurrence occurred in 11 patients (37.9%) after a median time of 22 months (range, 2-36 months). Eight patients (27.6%) were reoperated because of pain, whereas three patients were treated conservatively. The rate of recurrences did not significantly differ between patients presenting with (n = 7 of 12) or without (n = 4 of 17) local nerve infiltration (P = .119). All surgically treated patients who were diagnosed without preoperative imaging developed a relapse.

CONCLUSIONS

VMs in the region of the hand are difficult to treat, and surgery is associated with a high recurrence rate. Accurate diagnostic imaging and meticulous surgery may contribute to improve the outcome of the patients.

The VASCERN-VASCA Working Group Diagnostic and Management Pathways for Venous Malformations

To elaborate expert consensus patient pathways to guide patients and physicians toward efficient diagnostics and management of patients with venous malformations.

Methods

VASCERN-VASCA (https://vascern.eu/) is a European network of multidisciplinary centers for Vascular Anomalies. The Nominal Group Technique was used to establish the pathways. Two facilitators were identified: one to propose initial discussion points and draw the pathways, and another to chair the discussion. A dermatologist (AD) was chosen as first facilitator due to her specific clinical and research experience. The draft was subsequently discussed within VASCERN-VASCA monthly virtual meetings and annual face-to-face meetings.

Results

The Pathway starts from the clinical suspicion of a venous type malformation (VM) and lists the clinical characteristics to look for to support this suspicion. Strategies for subsequent imaging and histopathology are suggested. These aim to inform on the diagnosis and to separate the patients into 4 subtypes: (1) sporadic single VMs or (2) multifocal, (3) familial, multifocal, and (4) combined and/or syndromic VMs. The management of each type is detailed in subsequent pages of the pathway, which are color coded to identify sections on (1) clinical evaluations, (2) investigations, (3) treatments, and (4) associated genes. Actions relevant to all types are marked in separate boxes, including when imaging is recommended. When definite diagnoses have been reached, the pathway also points toward disease-specific additional investigations and recommendations for follow up. Options for management are discussed for each subtype, including conservative and invasive treatments, as well as novel molecular therapies.

Conclusion

The collaborative efforts of VASCERN-VASCA, a network of the 9 Expert Centers, has led to a consensus Diagnostic and Management Pathways for VMs to assist clinicians and patients. It also emphasizes the role of multidisciplinary expert centers in the management of VM patients. This pathway will become available on the VASCERN website (http://vascern.eu/).

Effectiveness and safety of percutaneous sclerotherapy using absolute ethanol and/or polidocanol for maxillofacial venous malformations involving the masticatory muscles: A case series

OBJECTIVE

This study evaluated the effectiveness and safety of percutaneous sclerotherapy for maxillofacial venous malformations.

STUDY DESIGN

Patients who had venous malformations involving the masticatory muscles and who underwent sclerotherapy were enrolled in this retrospective study.

RESULTS

Twenty-four patients (13 female, 11 male; mean age 21 years) were analyzed. Major clinical symptoms were swelling (100%) and intralesional pain (54%). Intramuscular lesions involved the masseter muscle only in 38% of cases, both the masseter and temporalis muscles in 33%, all masticatory muscles in 21%, and the temporalis muscle only in 8%. Extramuscular involvement was observed in 58% of patients. Absolute ethanol and polidocanol were used as sclerosants. The mean number of sclerotherapy sessions per patient was 6.6 (range, 1-32). The mean follow-up duration after the first sclerotherapy session was 64.8 months (range, 6-178). The complications included paralysis of the facial nerve (25%), intraoral ulceration (8%), and hemoglobinuria (8%). The effectiveness of treatment was rated as excellent in 33% of cases, good in 46%, and fair in 21%. Better results were obtained in patients without extramuscular involvement.

CONCLUSION

Percutaneous sclerotherapy can be effective and safe for maxillofacial intramuscular venous malformations, especially for localized lesions of the masseter muscle.

Assessment of Hormonal Contraceptive Utilization and Associated Odds of Hypercoagulopathy in Patients with Venous Malformations Using a National Claims Database

BACKGROUND

Vascular anomalies that exhibit a slow velocity of blood flow, specifically venous malformations (VM), are associated with hypercoagulability. There is limited literature on the utilization of hormonal contraceptives (HCs) and the development of clotting events in female individuals diagnosed with VM.

OBJECTIVE

We aimed to characterize HC utilization and associated odds of hypercoagulopathy in patients with VM of child-bearing age.

METHODS

Using a national administrative claims database, we identified female patients with VM aged 15-49 years and a control population, matched for age and length of insurance enrollment, from 2016 to 2021. Multivariable logistic regression was used to estimate the odds of hypercoagulation events associated with HC use.

RESULTS

Two hundred and sixty-seven (47.2%) patients with VM and 1284 (45.4%) control patients utilized HCs during the study period. Oral contraceptives were the most common HC for patients with and without VM (73.8% and 76.9% of those taking HCs, respectively), and estrogen-containing combination HCs (70.4% in patients with VM and 75.9% in controls) were more prevalent than progestin-only HCs in both populations. Despite a heightened baseline odds of hypercoagulopathy in patients with VM relative to patients without VM (odds ratio = 12.54; 95% confidence interval 7.73-20.3), HC use was not associated with an increased odds of hypercoagulation in the VM subpopulation (odds ratio = 0.82; 95% confidence interval 0.46-1.46). In contrast, tobacco use (odds ratio = 2.12; 95% confidence interval 1.09-4.12) and a history of coagulopathy (odds ratio = 3.92; 95% confidence interval 1.48-10.36) were predictive of thromboembolic events in the VM cohort.

CONCLUSIONS

These findings suggest that patients with VM may safely use HCs with careful consideration of other risk factors for thromboses.

Combined sclerotherapy followed by surgical resection of a large extracranial venous malformation in a 14-month-old child: preoperative workup and technical note

INTRODUCTION

Venous malformations affect around 2 per 10,000 newborn and are the most common type of congenital vascular malformation. They are always present at birth and are often misdiagnosed with hemangiomas. Accurate diagnosis and adequate targeted therapy through a multidisciplinary approach is advocated for a successful treatment, considering a combination of modalities in complex cases. We present here the workup and treatment of a venous malformation in a 14 month old child by combining a preoperative sclerotherapy with sodium tetradecyl sulfate (STS) followed by complete surgical excision respecting the calvarium.

CASE PRESENTATION

A large right extracranial fronto-parietal venous malformation and scalloping of the underlying calvarium, attached to the pericranium, surgically excised after preoperative sclerotherapy with STS in a 14-month-old child.

RESULTS

The patient had an uneventful postoperative course with complete resection of the lesion, satisfying cosmetic appearance and no complications. Histopathological examination confirmed a venous malformation.

CONCLUSION

We demonstrated the workup and the rationale of the combined sclerotherapy followed by surgical resection of a large growing extracranial venous malformation. Preoperative direct contrast injection and sclerotherapy allowed to rule out significative extracranial to intracranial venous inflow and reduce blood loss for the surgical procedure, respectively. Complete removal of the malformation minimized the impact on future growth of the calvarium.

Multicentered analysis of percutaneous sclerotherapies in venous malformations of the face

Objectives

To evaluate the safety and outcome of image-guided sclerotherapy for treating venous malformations (VMs) of the face.

Materials and methods

A multicenter cohort of 68 patients with VMs primarily affecting the face was retrospectively investigated. In total, 142 image-guided sclerotherapies were performed using gelified ethanol and/or polidocanol. Clinical and imaging findings were assessed to evaluate clinical response, lesion size reduction, and complication rates. Sub-analyses of complication rates depending on type and injected volume of the sclerosant as well as of pediatric versus adult patient groups were conducted.

Results

Mean number of procedures per patient was 2.1 (±1.7) and mean follow-up consisted of 8.7 months (±6.8 months). Clinical response (n = 58) revealed a partial relief of symptoms in 70.7% (41/58), 13/58 patients (22.4%) presented symptom-free while only 4/58 patients (6.9%) reported no improvement. Post-treatment imaging (n = 52) revealed an overall objective response rate of 86.5% (45/52). The total complication rate was 10.6% (15/142) including 4.2% (7/142) major complications, mostly (14/15, 93.3%) resolved by conservative means. In one case, a mild facial palsy persisted over time. The complication rate in the gelified ethanol subgroup was significantly higher compared to polidocanol and to the combination of both sclerosants (23.5 vs. 6.0 vs. 8.3%, p = 0.01). No significant differences in complications between the pediatric and the adult subgroup were observed (12.1 vs. 9.2%, p = 0.57). Clinical response did not correlate with lesion size reduction on magnetic resonance imaging (MRI).

Conclusion

Image-guided sclerotherapy is effective for treating VMs of the face. Clinical response is not necessarily associated with size reduction on imaging. Despite the complex anatomy of this location, the procedures are safe for both adults and children.

Surgical management of bilateral thoracic outlet lymphaticovenous malformations causing recurrent cerebrovascular accidents

Lymphaticovenous malformations (LVMs) are a rare subset of congenital vascular malformations that result from the defective development of the vascular and lymphatic systems during embryogenesis. LVMs can cause pathological mass effects or lead to thrombotic complications. We present a rare case of the surgical management of bilateral LVMs arising at the junction of the brachiocephalic and internal jugular veins in a patient with a patent foramen ovale, identifying the source of previously unexplained paradoxical cerebrovascular accidents.

A histological study of vascular wall resident stem cells in venous malformations

Vascular wall resident stem cells (VW-SCs) play a key role in vascular formation and remodeling under both physiological and pathological situations. They not only serve as a reservoir to supply all types of vascular cells needed, but also regulate vascular homeostasis by paracrine effects. Venous malformations (VMs) are common congenital vascular malformations which are just characterized by the deficient quantity and abnormal function of vascular cells. However, the existence and role of VW-SCs in VMs is still unclear at present. In this study, the level and distribution of VW-SCs in 22 specimens of VMs were measured by immunochemistry, double-labeling immunofluorescence, and qPCR, followed by the Spearman rank correlation test. We found that both the protein and mRNA expression levels of CD34, vWF, VEGFR2, CD44, CD90, and CD105 were significantly downregulated in VMs compared with that in normal venules. VW-SCs were sporadically distributed or even absent within and outside the endothelium of VMs. The expression of the VW-SC-related markers was positively correlated with the density of both endothelial cells and perivascular cells. All those results and established evidence indicated that VW-SCs were more sporadically distributed with fewer amounts in VMs, which possibly contributing to the deficiency of vascular cells in VMs.

Endothelial cells induce degradation of ECM through enhanced secretion of MMP14 carried on extracellular vesicles in venous malformation

Venous malformations (VMs), featuring localized dilated veins, are the most common developmental vascular anomalies. Aberrantly organized perivascular extracellular matrix (ECM) is one of the prominent pathological hallmarks of VMs, accounting for vascular dysfunction. Although previous studies have revealed various proteins involved in ECM remodeling, the detailed pattern and molecular mechanisms underlying the endothelium-ECM interplay have not been fully elucidated. Our previous studies revealed drastically elevated extracellular vesicle (EV) secretion in VM lesions. Here, we identified increased EV-carried MMP14 in lesion fluids of VMs and culture medium of TIE2-L914F mutant endothelial cells (ECs), along with stronger ECM degradation. Knockdown of RAB27A, a required regulator for vesicle docking and fusion, led to decreased secretion of EV-carried MMP14 in vitro. Histochemical analysis further demonstrated a highly positive correlation between RAB27A in the endothelium and MMP14 in the perivascular environment. Therefore, our results proved that RAB27A-regulated secretion of EV-MMP14, as a new pattern of endothelium-ECM interplay, contributed to the development of VMs by promoting ECM degradation.

GLMN causing vascular malformations: the clinical and genetic differentiation of cutaneous venous malformations

Cutaneous venous malformations frequently present with blue-pink lesions on the skin or mucosal surfaces. They can be problematic for patients who experience pain or unsightly lesions and can also be associated with significant bleeding. A proportion of venous malformations have been noted to occur in families, in particular glomuvenous malformations (GVMs). A 'two-hit' occurrence of genetic pathogenic variants appears to explain the appearance of GVMs, with the initial change in the germline copy of GLMN followed by a second somatic hit. Here we discuss a report of siblings experiencing such lesions, which were diagnosed as GVMs by genetic testing. We include a review of the literature regarding the clinical and genetic differences between these groups of venous malformations.

Multimodality Treatment of Vascular Anomalies of The Head And Neck

Vascular anomalies affect up to 5% of children with the majority affecting the head and neck. They present at different ages as a wide variety of lesions. Careful evaluation with history, physcial examination and imaging assist in the proper diagnosis. Depending on the condition, treatment options for vascular anomalies include topical therapy, selective photothermolysis, sclerotherapy, embolization, surgical excision and targeted systemic therapy. Staged multimodal therapeutic regimens have proven to best control disease and allow for preservation of function and aesthetics. The timing, sequence and combination of therapies is best determined by a multidisciplinary vascular anomalies team. Patients and families need to be counseled on anticipated positive outcomes following a protracted course of treatment for the majority of vascular anomalies.

Treatment of venous malformations with tumescent-assisted sclero-embolic and ablative lasers (SEALs): Safe and effective long-term outcomes

Background

Perivascular infiltration of tumescent anaesthesia (TA) is an essential element of endovenous thermal ablative procedures employed to treat superficial venous disease. In addition to anaesthesia, TA is administered to achieve vessel wall approximation and to protect surrounding structures from thermal damage. However, its role in the treatment of venous malformations (VMs) has not been established.

Objectives

To assess the safety and efficacy of tumescent-assisted thermal and chemical ablative methods in the treatment of VMs.

Methods

Adult and paediatric patients presenting with VMs were treated using a combination of endovenous laser ablation, foam embolo-sclerotherapy and liquid embolisation using n-BCA. All procedures were ultrasound-guided. Treatment outcomes were assessed in early and late follow-ups. To assess the efficacy of TA in achieving vessel wall approximation, cross-sectional lesional diameters were measured by ultrasound, before and after the administration of TA during endovenous procedures.

Results

In a 12 month period, 22 patients recruited in the study presented with 27 VMs which included 23 extra-truncular lesions (16 subcutaneous and seven intramuscular) and four truncular anomalies. On average the subcutaneous lesions measured 5.5 mm (1.9–24.5 mm) in diameter, intramuscular lesions measured 9.2 mm (5.9–15.1 mm) and truncular anomalies measured 4.9 mm (1.2–12 mm) in diameter. Perivascular infiltration of TA resulted in a significant reduction in vessel calibre (90% reduction on average). Intramuscular VMs were less compressible with TA (69.2% reduction) compared to subcutaneous lesions (98% reduction). Truncular anomalies such as the embryonic marginal vein achieved complete approximation (100% reduction). Procedures were safely tolerated with no major complications such as thromboembolism, stroke, nerve damage or tissue necrosis. Most patients had significant clinical as well as ultrasonographic improvement.

Conclusion

Tumescent-assisted endovenous laser ablation and foam sclerotherapy provides safe and effective outcomes in patients with a variety of VMs.

Palmar Venous Malformation: A Case Report of a Rare Occurrence and a Treatment Algorithm

Palmar venous malformations are not well described in the surgical literature and are a therapeutic challenge due to the intricate anatomy of the hand. We present the case of a 19-year-old right-handed female patient from Mexico who was referred to us with a right palmar lesion present since birth, previously diagnosed as a venous malformation. The patient reported that she had undergone sclerotherapy 10 years before in addition to a prior aborted attempt at excision. Venous palmar malformations are rare occurrences. Although an individualized approach is important, the development of an algorithm may assist in the standardization of the treatment of this pathology to preserve the hand’s functional status.

Interventional Treatment Options in Children with Extracranial Vascular Malformations

Extracranial vascular malformations vary greatly and belong to the complex field of orphan diseases and can involve all segments of the vascular tree: arteries, capillaries, and veins, and similarly the lymphatic system. The classification according to the International Society for the Study of Vascular Anomalies (ISSVA) represents an important guidance for selecting appropriate therapy. Although many of the principles of endovascular treatment, including image-guided sclerotherapy and embolization, are similar in adult and pediatric practice, there are some distinct differences regarding the treatment of vascular malformations of children. Thus, it is crucial to involve longer-term plan about managing these chronic diseases and their impact on a growing child. This review provides a detailed overview over the clinical presentation of venous, lymphatic, and arteriovenous malformations in children and emphasizes the specifics of their interventional treatment options, including distinct pediatric dose limitations and procedure-related side effects.

Severe absence of intra-orbital fat in a patient with orbital venous malformation: A case report

BACKGROUND

The orbital venous malformation is quite common in orbital diseases. Clinically, it is usually characterized by proptosis. However, among patients with distensible venous malformations, if the lesions continuously progress, they may induce enlargement of the orbital bone or orbital lipoatrophy, which in turn leads to enophthalmos.

CASE SUMMARY

Here, we report a patient who presented with enophthalmos and had a severe absence of intra-orbital fat secondary to orbital venous malformation. The patient was a 66-year-old female with a 20-year history of enophthalmos. Hertel exophthalmometry readings in a relaxed upright position were 4 mm OD and 13 mm OS with a 97 mm base. It was determined that she had positional “proptosis”. Physical examination also revealed a bulging mass on her hard palate. Computed tomographic scan and magnetic resonance imaging showed an expansion of the right orbit with local bony defects and multiple soft-tissue masses.

CONCLUSION

Long-term lack of awareness about the presence of orbital venous malformations, persistent venous congestion could lead to compression of the orbital fat, which in turn induces atrophy or the absence of intra-orbital fat.

Identification of ACTA2 as a Key Contributor to Venous Malformation

Objectives: Proteomics and high connotation functional gene screening (HCS) were used to screen key functional genes that play important roles in the pathogenesis of venous malformation. Furthermore, this study was conducted to analyze and explore their possible functions, establish a gene mutation zebrafish model, and perform a preliminary study to explore their possible pathogenic mechanisms in venous malformation.

Methods: Pathological and normal tissues from patients with disseminated venous malformation were selected for Tandem Mass Tag (TMT) proteomics analysis to identify proteins that were differentially expressed. Based on bioinformatics analysis, 20 proteins with significant differential expression were selected for HCS to find key driver genes and characterize the expression of these genes in patients with venous malformations. In vitro experiments were then performed using human microvascular endothelial cells (HMEC-1). A gene mutant zebrafish model was also constructed for in vivo experiments to explore gene functions and pathogenic mechanisms.

Results: The TMT results showed a total of 71 proteins that were differentially expressed as required, with five of them upregulated and 66 downregulated. Based on bioinformatics and proteomics results, five highly expressed genes and 15 poorly expressed genes were selected for functional screening by RNAi technology. HCS screening identified ACTA2 as the driver gene. Quantitative polymerase chain reaction (qPCR) and western blot were used to detect the expression of ACTA2 in the pathological tissues of patients with venous malformations and in control tissues, and the experimental results showed a significantly lower expression of ACTA2 in venous malformation tissues (P < 0.05). Cell assays on the human microvascular endothelial cells (HMEC-1) model showed that cell proliferation, migration, invasion, and angiogenic ability were all significantly increased in the ACTA2 over-expression group (P < 0.05), and that overexpression of ACTA2 could improve the inhibitory effect on vascular endothelial cell proliferation. We constructed an ACTA2-knockdown zebrafish model and found that the knockdown of ACTA2 resulted in defective vascular development, disruption of vascular integrity, and malformation of micro vein development in zebrafish. Further qPCR assays revealed that the knockdown of ACTA2 inhibited the Dll4/notch1 signaling pathway, Ephrin-B2 signaling pathway, and vascular integrity-related molecules and activated the Hedgehog signaling pathway.

Conclusion: This study revealed that ACTA2 deficiency is an important factor in the pathogenesis of venous malformation, resulting in the disruption of vascular integrity and malformed vascular development. ACTA2 can be used as a potential biomarker for the treatment and prognosis of venous malformations.

Radiologic-pathologic analysis of increased ethanol localization and ablative extent achieved by ethyl cellulose

Ethanol provides a rapid, low-cost ablative solution for liver tumors with a small technological footprint but suffers from uncontrolled diffusion in target tissue, limiting treatment precision and accuracy. Incorporating the gel-forming polymer ethyl cellulose to ethanol localizes the distribution. The purpose of this study was to establish a non-invasive methodology based on CT imaging to quantitatively determine the relationship between the delivery parameters of the EC-ethanol formulation, its distribution, and the corresponding necrotic volume. The relationship of radiodensity to ethanol concentration was characterized with water-ethanol surrogates. Ex vivo EC-ethanol ablations were performed to optimize the formulation (n = 6). In vivo ablations were performed to compare the optimal EC-ethanol formulation to pure ethanol (n = 6). Ablations were monitored with CT and ethanol distribution volume was quantified. Livers were removed, sectioned and stained with NADH-diaphorase to determine the ablative extent, and a detailed time-course histological study was performed to assess the wound healing process. CT imaging of ethanol-water surrogates demonstrated the ethanol concentration-radiodensity relationship is approximately linear. A concentration of 12% EC in ethanol created the largest distribution volume, more than eight-fold that of pure ethanol, ex vivo. In vivo, 12% EC-ethanol was superior to pure ethanol, yielding a distribution volume three-fold greater and an ablation zone six-fold greater than pure ethanol. Finally, a time course histological evaluation of the liver post-ablation with 12% EC-ethanol and pure ethanol revealed that while both induce coagulative necrosis and similar tissue responses at 1-4 weeks post-ablation, 12% EC-ethanol yielded a larger ablation zone. The current study demonstrates the suitability of CT imaging to determine distribution volume and concentration of ethanol in tissue. The distribution volume of EC-ethanol is nearly equivalent to the resultant necrotic volume and increases distribution and necrosis compared to pure ethanol.

Venous Malformations in Childhood: Clinical, Histopathological and Genetics Update

Our knowledge in vascular anomalies has grown tremendously in the past decade with the identification of key molecular pathways and genetic mutations that drive the development of vascular tumors and vascular malformations. This has led us to better understand the pathogenesis of vascular lesions, refine their diagnosis and update their classification while also exploring the opportunity for a targeted molecular treatment. This paper aims to provide an overview of venous malformations (VM) in childhood. Specific entities include common VMs, cutaneo-mucosal VM, blue rubber bleb nevus syndrome or Bean syndrome, glomuvenous malformation, cerebral cavernous malformation, familial intraosseous vascular malformation and verrucous venous malformation. The clinicopathological features and the molecular basis of each entity are reviewed.

Retinal Racemose Hemangioma With Optic Neuropathy in a Child

The aim of this study is to report an unusual case of retinal racemose haemangioma (RRH) in a child resulting in optic neuropathy and its optical coherence tomography angiography (OCT-A) findings. This is a retrospective case report.

For almost a year, a 13-year-old girl experienced gradual, painless, generalized blurred vision in her right eye. Visual acuity was 6/60 with a positive relative afferent pupillary defect (RAPD) in her right eye. The right-eye fundus showed enlarged and tortuous retinal vessels extending from the optic disc to all four quadrants, including the juxta foveal region. OCT analysis revealed distortion in the region of enlarged vessels with minimal retinal fluid while OCT-A of the macula area demonstrated dilated and tortuous vessels in the superficial layers of the retina. Right intra-orbital vascular channels surrounding the optic nerve with optic nerve atrophy and gliosis were detected on magnetic resonance imaging angiography/venography (MRA/MRV). The cerebral angiogram reported an abnormal tangle of small vessels within the right orbit that received supply from a dilated right ophthalmic artery indicating the presence of retro-orbital arteriovenous malformation (AVM). She was then referred to the neurosurgeon and a decision was made not to embolize or resect the dilated vessel as this might lead to occlusion of the ophthalmic artery and thus worsen her vision.

RRH may present in the paediatric age group, and optic nerve atrophy is one of the disease manifestations. OCT-A is a less invasive diagnostic option compared to fundus fluorescein angiography (FFA) for diagnosis and monitoring of disease progression.

Imaging of benign cervicofacial vascular anomalies and associated syndromes

Cervicofacial vascular anomalies can result in morbidity, pain, and cosmetic concerns in affected individuals. Each anomaly has its own unique natural history, treatment, and associations with underlying genetic syndromes. For optimal patient care, it is important for the neuroradiologist to accurately recognize and characterize these entities to ensure appropriate treatment and management. In this review, we discuss the general characteristics, classifications, and imaging features associated with the most common vascular anomalies such as hemangiomas, arteriovenous malformations and fistulas, capillary malformations, venous malformations, and lymphatic malformations in the context of associated syndromes. Additionally, we discuss novel imaging techniques that aid in identifying these vascular anomalies.

Intralesional diode laser pretreatment facilitates surgery for orbital venous malformations: initial experience with 23 consecutive patients

PURPOSE

This study aims to evaluate the efficacy and safety of intralesional diode laser pretreatment for facilitating surgery for orbital venous malformations (OVMs).

METHODS

This is a retrospective, non-comparative, interventional cohort involving 23 consecutive OVM patients undergoing intralesional laser pretreatment followed by surgical excision. The main outcome measures included volumetric changes, exophthalmometry, cosmesis, and symptom scores as well as treatment-related adverse events.

RESULTS

Following intralesional diode laser, the mean volume dropped significantly from 2366 ± 1887 to 129 ± 119 mm³ (t = 5.716; p < 0.001). After a single treatment session, a mean 90 ± 13% volume shrinkage was achieved in all 23 OVM. The mean Hertel exophthalmometry decreased significantly from 14 ± 3 to 13 ± 1 mm (t = 2.515; P < 0.02). The resolution of periocular dyschromasia and swelling were evident in 20 patients (87%). Symptom scores improved significantly from 6.5 ± 1.4 (very intense discomfort or effect on daily living) to 1.2 ± 1.0 (very mild discomfort or effect on daily living; p < 0.001). Short-term bruises and swelling were reported in 20 patients (87%).

CONCLUSION

Intralesional laser pretreatment is effective to facilitate surgery especially for the deep involving orbital venous malformations.

PIK3CA-related overgrowth spectrum (PROS): new insight in known diseases

The overgrowth syndromes related to phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K) are grouped under the concept of PROS (PIK3CA-related overgrowth spectrum). It is a heterogeneous group of diseases, considered a rare disease (ORPHA: 530313), which combines the presence of vascular malformations with segmental overgrowth of some parts of the body. All these diseases are caused by mutations in the gene that encodes for the alpha subunit of PI3K. These mutations are somatic and take place during the embryonic stage. Depending on the stage of embryonic development and the affected germ layers, the phenotype will be very different, from syndromes with extensive involvement to isolated forms. Although there are clinical criteria, identification of the mutation by biopsy, although complex, confirms the diagnosis. The objective of the present study is to review the pathophysiological, clinical, diagnostic, and therapeutic aspects of PROS, in order to optimize its identification.

A review of mechanisms of disease across PIK3CA-related disorders with vascular manifestations

BACKGROUND

PIK3CA-related disorders include vascular malformations and overgrowth of various tissues that are caused by postzygotic, somatic variants in the gene encoding phosphatidylinositol-3-kinase (PI3K) catalytic subunit alpha. These mutations result in activation of the PI3K/AKT/mTOR signaling pathway. The goals of this review are to provide education on the underlying mechanism of disease for this group of rare conditions and to summarize recent advancements in the understanding of, as well as current and emerging treatment options for PIK3CA-related disorders.

MAIN BODY

PIK3CA-related disorders include PIK3CA-related overgrowth spectrum (PROS), PIK3CA-related vascular malformations, and PIK3CA-related nonvascular lesions. Somatic activating mutations (predominantly in hotspots in the helical and kinase domains of PIK3CA, but also in other domains), lead to hyperactivation of the PI3K signaling pathway, which results in abnormal tissue growth. Diagnosis is complicated by the variability and overlap in phenotypes associated with PIK3CA-related disorders and should be performed by clinicians with the required expertise along with coordinated care from a multidisciplinary team. Although tissue mosaicism presents challenges for confirmation of PIK3CA mutations, next-generation sequencing and tissue selection have improved detection. Clinical improvement, radiological response, and patient-reported outcomes are typically used to assess treatment response in clinical studies of patients with PIK3CA-related disorders, but objective assessment of treatment response is difficult using imaging (due to the heterogeneous nature of these disorders, superimposed upon patient growth and development). Despite their limitations, patient-reported outcome tools may be best suited to gauge patient improvement. New therapeutic options are needed to provide an alternative or supplement to standard approaches such as surgery and sclerotherapy. Currently, there are no systemic agents that have regulatory approval for these disorders, but the mTOR inhibitor sirolimus has been used for several years in clinical trials and off label to address symptoms. There are also other agents under investigation for PIK3CA-related disorders that act as inhibitors to target different components of the PI3K signaling pathway including AKT (miransertib) and PI3K alpha (alpelisib).

CONCLUSION

Management of patients with PIK3CA-related disorders requires a multidisciplinary approach. Further results from ongoing clinical studies of agents targeting the PI3K pathway are highly anticipated.

Characteristics, clinical presentation, and treatment outcomes of venous malformation in the extremities

OBJECTIVE

The clinical presentation of venous malformations (VMs) is variable and not well documented. The present study was designed to determine the clinical characteristics and outcomes in association with the type and extent of VM in the extremities.

METHODS

Patients with a diagnosis of a VM using ultrasound, computed tomography, or magnetic resonance imaging were included in the present study. The VM extent and tissue involvement, signs, and symptoms were retrospectively collected. Those with arteriovenous malformations, Klippel-Trenaunay syndrome, lymphedema, and symptoms from other unrelated diseases were excluded. The VMs were classified as extensive or localized according to whether different tissues or the entire compartment was involved. The clinical outcomes and imaging studies were obtained for both the treated patients and those who had chosen to not undergo any intervention.

RESULTS

A total of 72 patients, of whom 26 were men, were included in the present study, with a median age of 30 years. The VM had extended into the subfascial space in 40 patients (55.6%). Patients with VM distributed on their leg had mostly experienced pain, which was more evident during physical activity (n = 40; 80.0%), with swelling worsening with prolonged standing (n = 35; 70.0%). For those with VMs in the upper extremities, the most prominent complaints were venous enlargement (n = 10; 45.5%), pain (n = 9; 40.9%), and swelling (n = 11; 50.0%). The symptoms were related to the extent of the lesion (odds ratio, 7.664; 95% confidence interval, 2.006-29.291; P = .003). Treatment was decided by the extent and depth of the lesions. Excision was performed in 15 patients (20.8%), sclerotherapy in 12 (16.7%), sclerotherapy with phlebectomy or coil embolization in 8 (11.1%), and stripping in 2 (2.8%). An excellent result was achieved with the treatment of localized VMs. For those with extensive VMs, the symptom intensity was reduced or controlled after multiple treatments.

CONCLUSIONS

VMs of the extremities affect patients' quality of life significantly owing their appearance and the resulting pain. The VM extent was associated with symptom severity. The clinical outcomes have been excellent for localized VMs; however, extensive VMs will require multiple treatments to reduce the symptom intensity.

Imaging features and enhancement technique to diagnose and classify intrathoracic Lymphatic-venous malformations: A case report and literature review

The diagnosis and treatment of pediatric intrathoracic lymphatic-venous malformations (LVM) can be complex due to their rarity, variable presentation and confusing nomenclature in the literature. The International Society for the Study of Vascular Anomalies (ISSVA) has recently (2018) updated their classification to help guide the correct diagnosis, nomenclature and management of such cases. We present the case of a 12-month-old Caucasian female with a lymph-venous malformation (LVM) classified in the updated ISSVA classification as a combined vascular malformation (CLVM) defined as two or more vascular malformations found in one lesion, associated with an underlying “malformation of an individual named vessel”. The patient presented with tachypnea, tachycardia and fever. While all the previous cases underwent surgical treatment, our patient was successfully treated with rapamycin and sclerotherapy. Appropriate imaging can aid in the diagnosis of vascular anomalies and in the proper ISSVA classification, saving the patient the need for a biopsy and allow for proper referral to Multidisciplinary Vascular Anomalies centers. The accurate classification can identify cases that can be treated through Interventional Radiology with sclerosing agents and medical therapy as opposed to surgery.

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.

Vascular endothelial cell specification in health and disease

There are two vascular networks in mammals that coordinately function as the main supply and drainage systems of the body. The blood vasculature carries oxygen, nutrients, circulating cells, and soluble factors to and from every tissue. The lymphatic vasculature maintains interstitial fluid homeostasis, transports hematopoietic cells for immune surveillance, and absorbs fat from the gastrointestinal tract. These vascular systems consist of highly organized networks of specialized vessels including arteries, veins, capillaries, and lymphatic vessels that exhibit different structures and cellular composition enabling distinct functions. All vessels are composed of an inner layer of endothelial cells that are in direct contact with the circulating fluid; therefore, they are the first responders to circulating factors. However, endothelial cells are not homogenous; rather, they are a heterogenous population of specialized cells perfectly designed for the physiological demands of the vessel they constitute. This review provides an overview of the current knowledge of the specification of arterial, venous, capillary, and lymphatic endothelial cell identities during vascular development. We also discuss how the dysregulation of these processes can lead to vascular malformations, and therapeutic approaches that have been developed for their treatment.

A Xenograft Model for Venous Malformation

Xenograft models allow for an in vivo approach to monitor cellular functions within the context of a host microenvironment. Here we describe a protocol to generate a xenograft model of venous malformation (VM) based on the use of human umbilical vein endothelial cells (HUVEC) expressing a constitutive active form of the endothelial tyrosine kinase receptor TEK (TIE2 p.L914F) or patient-derived EC containing TIE2 and/or PIK3CA gene mutations. Hyperactive somatic TIE2 and PIK3CA mutations are a common hallmark of VM in patient lesions. The EC are injected subcutaneously on the back of athymic nude mice to generate ectatic vascular channels and recapitulate histopathological features of VM patient tissue histology. Lesion plugs with TIE2/PIK3CA-mutant EC are visibly vascularized within 7-9 days of subcutaneous injection, making this a great tool to study venous malformation.

Monomelic Maffucci syndrome

Maffucci syndrome is a rare congenital, non-hereditary condition characterised by presence of multiple enchondromas and haemangiomas. Enchondromatous lesions affecting epiphysial growth plates can lead to angular deformities and leg-length discrepancy in the lower limb. We describe a 12-year-old girl with monomelic Maffucci syndrome affecting her left lower limb. She presented with progressive genu valgus deformity of her left knee. This caused her to limp during her gait and was a cosmetic dissatisfaction. The deformity affected her quality of life. She underwent a supracondylar distal femoral corrective osteotomy with a successful clinical outcome and restoration of her gait and cosmetic deformity.

Fluoroscopy-guided endoscopic sclerotherapy: a novel hybrid approach for symptomatic rectosigmoidal venous malformation (with video)

BACKGROUND AND AIMS

Recommendations for the treatment of lower GI bleeding do not include bleeding from venous malformations (VMs). The aim of this study was to delineate the usefulness of a novel hybrid intervention (fluoroscopy-guided endoscopic sclerotherapy) for the treatment of symptomatic VMs in the rectosigmoidal colon with bleeding.

METHODS

The magnetic resonance images of 421 patients with VM, referred to multicenter vascular anomaly centers from 2009 to 2017, were analyzed retrospectively. Treatment was performed for all patients who experienced bleeding from rectosigmoidal VMs using fluoroscopy-guided endoscopic sclerotherapy with polidocanol foam as a novel approach.

RESULTS

A total of 27 patients displayed VM in the rectosigmoidal area. Eleven of these presented with acute or previous bleeding and received treatment. Active bleeding was observed in 8 patients (72.7%), whereas 3 patients (27.3%) had signs of previous bleeding. Six of the 11 patients had anemia (54.5%). There were no adverse events within 24 hours of the intervention. In a 2-year follow-up period, only 1 patient (9.1%) presented with recurrent bleeding after 13 months and was successfully treated again with fluoroscopy-guided endoscopic sclerotherapy.

CONCLUSIONS

Fluoroscopy-guided endoscopic sclerotherapy was shown to be a safe and effective treatment of symptomatic VMs of the rectosigmoidal area. Thus, fluoroscopy-guided endoscopic sclerotherapy should be considered for patients with bleeding from VMs of the rectosigmoid after a comprehensive workup and interdisciplinary case discussion.

Analyzing coagulation dynamics during treatment of vascular malformations with thromboelastography

BACKGROUND/OBJECTIVES

Slow-flow vascular malformations are abnormal vessels that can lead to activation and consumption of coagulation factors and thrombosis, known as localized intravascular coagulopathy (LIC). Most clinical and research evidence of vascular malformation hemostasis relies on conventional coagulation studies, which may not provide a complete picture. Thromboelastograpy (TEG) is a tool that can provide real-time assessment of a patient's coagulation dynamics, and may allow for a more individualized treatment approach. We hypothesized that patients with slow-flow vascular malformations will have changes in TEG parameters peri-procedure that will help predict blood product or medication administration.

DESIGN/METHODS

Institutional Review Board approved prospective study of patients with slow-flow vascular malformations undergoing a sedated, minor procedure. TEG and conventional coagulation studies were obtained preprocedure, 15 min, and when possible, at 30 min after the start of the procedure.

RESULTS

Twenty-five patients were enrolled. Median age was 15 years (range 3-47 years). Procedures included laser and/or sclerotherapy. There were no changes in TEG parameters from baseline to 15 min or 30 min. The following decreased from baseline to 15 min: fibrinogen 313 to 287 mg/dL (P = .001), D-dimer 1.3 to 1.1 mg/L (P = .02), hemoglobin 12.8 to 11.8 g/dL (P = .001), and platelet count 272 000 to 256 000 (P = .006). No patient had a bleeding/thrombotic complication during or within 1 week postprocedure.

CONCLUSION

We saw no change in TEG parameters or bleeding or clotting complications despite significant numerical changes in conventional coagulation profiles, suggesting that conventional studies may not be as useful in determining risks of bleeding or thrombotic complications peri-procedure for minor procedures.

Genetic syndromes with vascular malformations - update on molecular background and diagnostics

Vascular malformations are present in a great variety of congenital syndromes, either as the predominant or additional feature. They pose a major challenge to the clinician: due to significant phenotype overlap, a precise diagnosis is often difficult to obtain, some of the malformations carry a risk of life threatening complications and, for many entities, treatment is not well established. To facilitate their recognition and aid in differentiation, we present a selection of notable congenital disorders of vascular system development, distinguishing between the heritable germinal and sporadic somatic mutations as their causes. Clinical features, genetic background and comprehensible description of molecular mechanisms is provided for each entity.

Use of percutaneous foam sclerotherapy with 1.5% sodium tetradecyl sulfate for treatment of a pelvic limb venous malformation in a dog

CASE DESCRIPTION

A 6-year-old 17-kg (37.4-lb) spayed female mixed-breed dog was evaluated because of swelling and intermittent lameness of the right pelvic limb and perianal and vulvar bleeding caused by a suspected arteriovenous malformation.

CLINICAL FINDINGS

The right pelvic limb had a diffuse, raised, cobblestone-like appearance with lameness, edema, and multifocal ulcerations. The abdominal skin had multifocal circular erythematous lesions, the perianal region was erythematous, and the vestibule had superficial distended vessels. Ultrasonography and CT did not reveal the presence of an arteriovenous malformation; however, digital subtraction venography confirmed the presence of a venous malformation (VM) throughout the limb.

TREATMENT AND OUTCOME

A mixture of foam sclerosant (1.5% sodium tetradecyl sulfate) and contrast medium was agitated with air and injected percutaneously into the VM. The dog received an injection of corticosteroid solution, and a soft-padded bandage was applied to the limb for 3 days. Six weeks later, the dog would intermittently hop when running, and the limb was mildly edematous with ecchymotic lesions; the swelling and lameness had improved considerably. Perianal and vulvar bleeding and dilation of the vestibular vessels had resolved. At 21 months after the procedure, examination revealed no right pelvic limb lameness related to the VM; only small cyst-like lesions and edema around the tarsus remained.

CLINICAL RELEVANCE

The favorable clinical outcome for this dog for a 21-month period after treatment of a pelvic limb VM with foam sclerotherapy has suggested that foam sclerotherapy may be used to successfully treat limb VMs in some dogs.

Venous malformations: Coagulopathy control and treatment methods

Venous malformations (VMs) are ectatic channels which arise as a result of vascular dysmorphogenesis, commonly caused by activating mutations in the endothelial tyrosine kinase receptor (TIE2)/phosphatidylinositol 3-kinase (PI3Kinase) pathway. With a prevalence of 1% in the general population, and a diverse clinical presentation depending on site, size and tissue involvement, their treatment requires a personalised and multidisciplinary approach. Larger lesions are complicated by local intravascular coagulopathy (LIC) causing haemorrhagic and/or thrombotic complications which can progress to disseminated intravascular coagulopathy (DIC).

METHODS

We performed a literature review using a PubMed® search and identified 15 articles to include. References of these texts were examined to further expand the literature review.Principle findings: Several treatment options have been explored, including compression, sclerotherapy, laser therapy, cryoablation and surgery in addition to the management of LIC with low-molecular-weight-heparin (LMWH) and other anticoagulants. Targeted molecular therapies acting on the phosphatidylinositol 3-kinase (PI3Kinase)/Protein Kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway are newly emerging.

CONCLUSION

Despite a wealth of literature, larger, multi-centric, randomised and prospective trails are required to offer further clarification on the therapeutic management of coagulopathy control and to provide symptomatic benefit to patients with VMs. There should be efforts to provide long term follow up and to use standardised risk stratification tools and quality of life (QOL) questionnaires to aid comparison of agents and treatment protocols.

Vascular anomalies: special considerations in children

The diagnosis and treatment of vascular anomalies are a large part of the caseload for paediatric interventional radiologists. Although many of the principles of sclerotherapy and embolisation are the same in adult and paediatric practice, there are some key differences in the approach for children, including some longer term thinking about managing these chronic diseases and their impact on a growing child. Vascular tumours are not often seen in adult IR practice and the rarest can be life threatening; knowledge of the commonest types and the role IR can play in their management can be instrumental in ensuring that children get appropriate treatment in a timely manner. Vascular anomalies also encompass some conditions associated with complex overgrowth, a subject that often causes confusion and uncertainty for interventional radiologists. This paper presents a simplified and practical approach to this spectrum of disease.

Image-guided percutaneous sclerotherapy of venous malformations of the head and neck: Clinical and MR-based volumetric mid-term outcome

Objective

To report the clinical and MRI-based volumetric mid-term outcome after image guided percutaneous sclerotherapy (PS) of venous malformations (VM) of the head and neck.

Methods

A retrospective analysis of a prospectively maintained database was performed, including patients with VM of the head and neck who were treated with PS. Only patients with available pre- and post-interventional MRI were included into this study. Clinical outcome, which was subjectively assessed by the patients, their parents (for paediatric patients) and/or the physicians, was categorized as worse, unchanged, minor or major improvement. Radiological outcome, determined by MRI-based volumetric measurements, was categorized as worse (>10% increase), unchanged (≤10% increase to <10% decrease), minor (≥10% to <25% decrease), intermediate (≥25% to <50% decrease) or major improvement (≥50% decrease).

Results

Twenty-seven patients were treated in 51 treatment sessions. After a mean follow-up of 31 months, clinical outcome was worse for 7.4%, unchanged for 3.7% of the patients, while there was minor and major improvement for 7.4% and 81.5%, respectively. In the volumetric imaging analysis 7.4% of the VMs were worse and 14.8% were unchanged. Minor improvement was observed in 22.2%, intermediate improvement in 44.4% and major improvement in 11.1%. The rate of permanent complications was 3.7%.

Conclusion

PS can be an effective therapy to treat the symptoms of patients with VMs of the head and neck and to downsize the VMs. MRI-based volumetry can be used to objectively follow the change in size of the VMs after PS. Relief of symptoms frequently does not require substantial volume reduction.

Vascular anomalies of the head and neck

The head and neck are the most common site of involvement for vascular tumors and malformations, with more than half of all vascular anomalies seen in this region. Lesions in this location can cause significant disfigurement and can be associated with airway obstruction, impairment in vision or hearing, swallowing disorders and hemorrhage. Accurate diagnosis is critical in determining treatment, and interdisciplinary care is essential for optimal management. We review clinical and imaging features that are key to establishing the correct diagnosis, and review treatment modalities, with emphasis on interventional and surgical procedures.