Sclerotherapy for low-flow vascular malformations of the orbital and periocular regions: Systematic review and meta-analysis

Image-Guided Percutaneous Sclerotherapy for Orbital Low-Flow Malformation: Our Experience

For a safe sclerotherapy session to be completed in the orbital low-flow malformation (namely lymphovenous malformation or venolymphatic malformation), accurate identification of the target lesion for the drug injection is crucial. Regarding the dependability and viability of the injection approach, the authors have discussed their experiences with image-guided percutaneous sclerotherapy on a few patients.

A systematic review and network meta-analysis of the effectiveness of sclerotherapy for venous malformation

OBJECTIVE

Sclerotherapy for venous malformation has been widely used; however, no guidelines are available to assess the effectiveness of different sclerotherapy agents. We conducted a systematic review and network meta-analysis to investigate the effectiveness of sclerotherapy agents for venous malformations.

METHODS

Three electronic databases were searched from their inception (1950) to April 29, 2021. Studies comparing the effectiveness of different sclerotherapy agents were included. The risk of bias within and across studies was assessed. Pairwise meta-analyses were conducted, followed by a network meta-analysis. We also assessed inconsistency and publishing bias using various approaches.

RESULTS

Seven studies with 547 patients in six arms were included in the present study. We defined the response and complete response as two separate outcomes. Significant differences were observed in four comparisons with respect to the response (ethanol vs bleomycin, ethanol vs polidocanol, ethanol vs sodium tetradecyl sulfate, polidocanol vs sodium tetradecyl sulfate). No statistically significant differences were found in the other comparisons. The evidence network revealed that for the response outcome, ethanol ranked first, followed by pingyangmycin, polidocanol, sodium morrhuate, bleomycin, and, finally, sodium tetradecyl sulfate. For the complete response outcome, pingyangmycin had the best results, followed by sodium morrhuate, polidocanol, ethanol, bleomycin, and, finally, sodium tetradecyl sulfate. Major complications, such as facial nerve palsy, serious local swelling, and necrosis, had occurred mostly in the ethanol group and rarely in the other groups. Because of the limited data, no further analysis of major complications was conducted. Our confidence in the comparisons and rankings was low. We found no verified inconsistency or publishing bias in the present study using the existing approaches.

CONCLUSIONS

Ethanol showed a significantly better response statistically compared with the other agents. However, ethanol had also resulted in the highest incidence of complications. Pingyangmycin showed the second-best response, best complete response, and a low rate of complications, respectively. Overall, pingyangmycin achieved excellent performance and balance in terms of the different outcomes. However, they could not be adequately recommended from the available data. More superior trials, especially randomized controlled trials, are needed in the future.

Intermittent Orbital Pain due to Hemodynamic Collapse of an Orbital Varix: A Case Report

Orbital varices typically present with symptoms related to dilation or thrombosis. We describe a rare presentation of an orbital varix with pain caused by hemodynamic collapse of the varix. A woman in the third decade presented with position-dependent orbital pain and enophthalmos. She was found to have an intraorbital varix and a separate pterygoid varix. The patient underwent endovascular treatment of the pterygoid varix using coils and sclerosing agents which altered the venous outflow from the orbital varix. The patient had immediate resolution of symptoms after the procedure. Our findings suggest that extraorbital venous outflow abnormalities may be the cause of symptoms in selected cases of orbital varices. By understanding the venous structures on cerebral angiography and treating the extraorbital component, orbital intervention may be avoided, reducing the risk of complications.

Polidocanol monotherapy for a superficial orbital venous malformation in a horse

OBJECTIVE

To describe the use of 1% polidocanol as the sole treatment for a superficial orbital venous malformation in a horse.

ANIMAL

A 23-year-old Welsh Cobb cross gelding with a distensible swelling affecting the left lower eyelid, and secondary palpebral margin abnormalities and superficial keratitis.

PROCEDURE

Color flow Doppler ultrasonography revealed non-pulsatile blood flow within the tortuous vascular network most consistent with a superficial orbital venous malformation appearing to involve the lateral palpebral and transverse facial veins. An intravenous catheter was placed within the lateral aspect of the venous malformation, and agitated saline was slowly injected into the vessel while simultaneously ultrasound imaging the medial aspect in which the bubbles were observed coursing across, consistent with lateral to medial flow. Contrast venography confirmed a corkscrew vessel along the ventral aspect of the orbital rim. Under standing sedation, 1% polidocanol solution was administered slowly through the intravenous catheter while manual pressure was applied on the medial and lateral aspects of the venous malformation.

RESULTS

Ultrasonography performed immediately after administration of polidocanol confirmed venous stasis, and formation of a thrombus. No adverse side effects were noted. The venous malformation and associated palpebral margin abnormalities and superficial keratitis resolved at the time of re-examination at 4 months.

CONCLUSION AND CLINICAL RELEVANCE

Polidocanol as the sole treatment for a superficial orbital venous malformation in a horse was well tolerated and led to clinical resolution. Sclerosant monotherapy may be a safe treatment option for superficial orbital venous malformations.

Severe orbital inflammation and hemorrhage complicating bleomycin sclerotherapy for orbital lymphaticovenous malformation

Percutaneous sclerotherapy is a well-recognized treatment for management of low-flow vascular malformations. It is regarded as a safe and effective procedure, and there are very few reports of sight-threatening complications in the medical literature. We describe a case of a 12-year-old girl who developed severe orbital compartment syndrome due to a combination of orbital inflammation and hemorrhage, resulting in massive proptosis, severe chemosis, optic nerve compression, severe lagophthalmos, exposure keratitis and visual loss following bleomycin sclerotherapy for a right orbital and periorbital lymphaticovenous malformation. Despite presenting to the emergency eye clinic 5 days after the onset of her symptoms, when her vision was thought to be irretrievably lost, she had a surprisingly good visual outcome after medical and surgical intervention. Although sclerotherapy for low-flow vascular malformations of the orbit is generally safe, it can be complicated by severe sight-threatening orbital inflammation and hemorrhage for which urgent intervention is usually required. However, with adequate management, visual recovery may occur even after late presentation.

Recurrence of Distensible Orbital Venous-dominant Venolymphatic Malformations After Sclerotherapy Versus Embolization With Excision

PURPOSE

Treatment for orbital venolymphatic malformations (VLMs) commonly includes 3 major options: sclerotherapy, surgery, and embolization followed by surgical excision. Each has certain advantages, although it is not clear whether all are effective. The authors characterize the clinical course for a series of patients with distensible orbital venous-dominant VLM treated with sclerotherapy and/or embolization with excision.

METHODS

In this cross-sectional cohort study, patients affected by distensible orbital venous-dominant VLM presenting to the orbital and ophthalmic plastic surgery service from 2014 to 2020 were identified. Patients were included if they presented with a moderate-flow, distensible venous-dominant malformation associated with Valsalva-related symptoms (e.g., pain, proptosis, and diplopia).

RESULTS

Six cases were treated with sclerotherapy. Four underwent multiple treatments, with a mean ± SD of 3.5 ± 2.3 (range 1-7). All patients in this group failed to improve or experienced recurrence of symptoms after sclerotherapy. Twelve cases were treated with embolization and excision. Resolution of symptoms in all 12 cases was noted and maintained for a mean of 3.4 ± 2.1 years. There have been no cases of recurrence. Patients treated with sclerotherapy were more likely to experience recurrence of symptoms compared to those treated with embolization and excision (p < 0.001).

CONCLUSIONS

Treatment of distensible venous-dominant moderate-flow orbital VLM with sclerotherapy may provide temporary improvement in some cases. However, in the medium to long term, recurrence was universal in this series. Embolization with excision appears to provide more definitive management, avoiding recurrence in all cases for a mean follow-up of 3 years.

Clinical Assessment and Lesion-Specific Management of Orbital Vascular Malformations

The systematic classification of vascular disease as proposed and refined by the International Society for the Study of Vascular Anomalies (ISSVA) divides vascular pathology first into tumors and malformations. Malformations are described as simple and complex, where simple malformations contain a single vascular system and complex malformations comprised of multiple vascular systems. Arteriovenous malformations are considered in terms of inflow characteristics which are primarily responsible for the key management challenges. Management utilizing endovascular embolization and/or surgical resection is often employed; however, recurrence can occur, particularly in diffuse cases. There may be an increasing role for systemic antiangiogenic therapy in such cases. Lymphaticovenous malformations are divided into the principle components on the lymphatic and venous sides for clarity of discussion. Lymphatic malformations are described morphologically as macrocystic and microcystic, and physiologically in terms of the processes responsible for growth. In both cases, surgical options are challenging and local therapeutics intended to close large luminal spaces in the case of macrocystic and to slow biological signaling for growth in microcystic. Venous malformations are described physiologically in terms of flow and distensibility, as volume plays a critical role in the limited space of the orbital cavity. Combined embolic-surgical approaches can be effective for management. More complicated, combined lesions can be managed by dividing the lesion into principal components and treating each appropriately.

AKT/FOXO1 axis links cross-talking of endothelial cell and pericyte in TIE2-mutated venous malformations

Background

Venous malformations (VMs), most of which associated with activating mutations in the endothelial cells (ECs) tyrosine kinase receptor TIE2, are characterized by dilated and immature veins with scarce smooth muscle cells (SMCs) coverage. However, the underlying mechanism of interaction between ECs and SMCs responsible for VMs has not been fully understood.

Methods

Here, we screened 5 patients with TIE2-L914F mutation who were diagnosed with VMs by SNP sequencing, and we compared the expression of platelet-derived growth factor beta (PDGFB) and α-SMA in TIE2 mutant veins and normal veins by immunohistochemistry. In vitro, we generated TIE2-L914F-expressing human umbilical vein endothelial cells (HUVECs) and performed BrdU, CCK-8, transwell and tube formation experiments on none-transfected and transfected ECs. Then we investigated the effects of rapamycin (RAPA) on cellular characteristics. Next we established a co-culture system and investigated the role of AKT/FOXO1/PDGFB in regulating cross-talking of mutant ECs and SMCs.

Results

VMs with TIE2-L914F mutation showed lower expression of PDGFB and α-SMA than normal veins. TIE2 mutant ECs revealed enhanced cell viability and motility, and decreased tube formation, whereas these phenotypes could be reversed by rapamycin. Mechanically, RAPA ameliorated the physiological function of mutant ECs by inhibiting AKT-mTOR pathway, but also facilitated the nuclear location of FOXO1 and the expression of PDGFB in mutant ECs, and then improved paracrine interactions between ECs and SMCs. Moreover, TIE2 mutant ECs strongly accelerated the transition of SMCs from contractile phenotype to synthetic phenotype, whereas RAPA could prevent the phenotype transition of SMCs.

Conclusions

Our data demonstrate a previously unknown mechanistic linkage of AKT-mTOR/FOXO1 pathway between mutant ECs and SMCs in modulating venous dysmorphogenesis, and AKT/FOXO1 axis might be a potential therapeutic target for the recovery of TIE2-mutation causing VMs.