Vascular Malformations of the Orbit: Classification and the Role of Imaging in Diagnosis and Treatment Strategies*

Circular RNAs in Vascular Functions and Diseases

Vascular disease is one of the top five causes of death and affects a variety of other diseases, such as heart, nervous system, and metabolic disorders. Vascular dysfunction is a hallmark of ischemia, cancer, and inflammatory diseases and can accelerate the progression of diseases. Circular RNAs (circRNAs) are a new type of noncoding RNAs with covalent bond ring structure, which have been reported to be abnormally expressed in many human diseases. circRNAs regulate gene expression through the sponging of microRNAs (miRNAs) and can also be used as disease biomarkers. Here we will summarize the functions of circRNAs in vascular diseases, including vascular dysfunction, atherosclerosis, diabetes mellitus-related retinal vascular dysfunction, chronic thromboembolic pulmonary hypertension, carotid atherosclerotic disease, hepatic vascular invasion in hepatocellular carcinoma, aortic aneurysm, coronary artery disease, and type 2 diabetes mellitus.

Image-Guided Percutaneous Bleomycin and Bevacizumab Sclerotherapy of Orbital Lymphatic Malformations in Children

PURPOSE

To evaluate the effectiveness and safety of image-guided percutaneous sclerotherapy using bleomycin for macrocystic and bevacizumab (Avastin™) for microcystic orbital lymphatic malformations in children.

MATERIALS AND METHODS

Between October 2015 and July 2018, we prospectively evaluated 10 pediatric patients who presented clinically and radiologically with lymphatic malformations and were treated with percutaneous sclerotherapy. Patients with venous malformations were excluded. Eight females and two males with ages ranging from 3 to 17 years (mean: 8.8, SD: 4.9) were included. Guided with ultrasound and fluoroscopy, macrocysts were treated with bleomycin instillation. For microcystic components in three patients, bevacizumab was injected intralesional. All patients underwent ultrasound and non-contrast MRI to evaluate response to treatment after 6 weeks.

RESULTS

The malformations were macrocystic in seven patients and complex (macro/microcystic) in three. Twenty sclerotherapy sessions were performed, (range: 1-3 sessions, mean: 2, SD: 0.8). Clinically, there was a significant reduction in the proptosis after treatment (P = 0.007) and dystopia (P = 0.018). The local radiological response showed a reduction in the maximum lesions diameters and volumes after treatment (P = 0.005 and 0.005, respectively). Two of the three patients treated with bevacizumab showed a reduction in the lesions volumes by 90.4% and 63.4%, respectively, whereas one patient did not show volume reduction. Transient periorbital edema and ecchymosis occurred following the procedure with no major complications encountered. Follow-up ranged from 9-33 months, mean: 20.3, SD: 7.4.

CONCLUSION

Bleomycin sclerotherapy is a safe and effective treatment for orbital macrocystic lymphatic malformations. Further use of bevacizumab for microcystic lesions in a larger series is required to outline its efficacy and safety.

Low-Flow Orbital Venous Malformation Masquerading as Rhabdomyosarcoma

A 15-month-old male was referred for biopsy of presumed rhabdomyosarcoma in the setting of rapidly progressing left-sided proptosis. Examination revealed left periorbital edema and left hypoglobus. MRI revealed a soft-tissue density mass within the left lateral retrobulbar space. Several days later, he developed acute periorbital ecchymosis and increasing edema. With high suspicion for a vascular lesion, a CT scan was performed with dynamic arterial and venous imaging. Central filling was noted in the lateral retrobulbar component with increased enhancement on delayed venous imaging in the middle cranial fossa component favoring the diagnosis of a low-flow orbital venous malformation. In the setting of spontaneous orbital hemorrhage and risk of future vision loss, the decision was made to proceed with a combined neurosurgical approach treating the intracranial component and debulking the orbital component. This case highlights the importance of thorough radiographic evaluation prior to proceeding with a surgical procedure in the appropriate clinical context.

Vascular malformations of the orbit (lymphatic, venous, arteriovenous): Diagnosis, management and results

Vascular malformations are often found inside the orbit. Isolated venous malformations (frequently misnamed as cavernous hemangiomas) are the most frequent among these. However, also lymphatic and arteriovenous malformations can affect the orbit. The complex anatomy of the orbit and the fact that its content easily suffers from compartmental syndrome explain why treating orbital vascular malformations can be challenging and technically demanding. In this study, two institutions have retrospectively collected their cases, consisting in a total of 69 vascular malformations of the orbit. Each type of malformation has been evaluated separately in terms of diagnosis, indications for treatment, techniques and outcomes. Moreover, the authors have analyzed in detail venous malformations, identifying three different types, named orbital venous malformation (OVM) 1, 2 and 3. These behave differently from each other, and a prompt differential diagnosis is mandatory to pose correct indications, minimize risks and improve results. Overall, surgery was the technique of choice for OVM1, microcystic lymphatic malformations (LM) and arteriovenous malformations (AVM). A pure transnasal approach with mass removal and reconstruction of the medial wall with polyethylene sheets was chosen for OVM1 (intra- or extraconal) located in the medial or superomedial compartment. Sclerotherapy had a role in treating macrocystic LM and OVM3.

Vascular Anomalies of the Orbit--A Reappraisal

The recent International Society for the Study of Vascular Anomalies (ISSVA) classification of vascular anomalies can be applied to orbital lesions, dividing them into vascular tumors and vascular malformations. Orbital cavernous hemangiomas are probably best considered cavernous venous malformations under this classification. Management of symptomatic lesions can be with surgical excision or stereotactic fractionated radiotherapy in selected cases. Beta-blockers including propranolol and topical timolol maleate represent first-line therapy for infantile hemangiomas, although surgery has a role in selected cases. Orbital venous-lymphatic malformations are problematic but with improved imaging, neuroradiological intervention, and a multidisciplinary approach to management, outcomes are improving.

Classification and treatment of orbital venous malformations: an updated review

Orbital venous malformation (OVM) is a congenital vascular disease. As a common type of vascular malformation in the orbit, OVM may result in vision deterioration and cosmetic defect. Classification of orbital vascular malformations, especially OVMs, is carried out on the basis of different categories, such as angiogenesis, hemodynamics, and locations. Management of OVM is complicated and challenging. Treatment approaches include sclerotherapy, laser therapy, embolization, surgical resection, and radiotherapy. A satisfactory outcome can be achieved only by selecting the appropriate treatment according to lesion characteristics and following the sequential multi-method treatment strategy. This article summarizes the current classification and treatment advances in OVM.

Diagnosing Distensible Venous Malformations of the Orbit With Diffusion-weighted Magnetic Resonance Imaging

PURPOSE

To compare the diffusion-weighted imaging of nonthrombosed distensible venous malformations of the orbit with that of other histologically-proven orbital tumors.

DESIGN

Retrospective case-control study.

METHODS

Patients with nonthrombosed distensible venous malformations of the orbit and patients with other histologically-proven orbital tumors were selected for chart review. The main outcome measure was the apparent diffusion coefficient of these lesions.

RESULTS

Sixty-seven patients qualified for chart review; 9 patients had nonthrombosed distensible venous malformations and 58 patients had other histologically-proven tumors. Three of the 9 patients with nonthrombosed distensible venous malformations were initially misdiagnosed as having had solid orbital tumors. The mean apparent diffusion coefficient of distensible venous malformations was 2.80 ± 0.48 × 10^-3 mm²/s, whereas the mean apparent diffusion coefficient of other histologically-proven tumors was 1.18 ± 0.39 × 10^-3 mm²/s (P < .001). The mean apparent diffusion coefficient ranged from 2.42 to 3.94 × 10^-3 mm²/s in the distensible venous malformation group, whereas other histologically-proven tumors ranged from 0.53 to 2.08 × 10^-3 mm²/s. Therefore, in this single-institution series, a threshold value of 2.10 × 10^-3 mm²/s was 100% sensitive and 100% specific for distensible venous malformations.

CONCLUSION

Certain nonthrombosed distensible venous malformations can evade diagnostic suspicion and mimic solid orbital tumors on standard magnetic resonance imaging sequences. In this single-institution series, diffusion-weighted imaging effectively distinguished these nonthrombosed distensible venous malformations from other orbital tumors.

Orbital Lymphaticovenous Malformation with Intradural Extension: Rare Case

BACKGROUND

Orbital lymphaticovenous malformations (LVMs) are congenital vascular lesions that are typically infiltrative in nature. There have been reports of orbital LVMs extending intracranially through orbital fissures, but there have been no reports of intradural extension.

CASE DESCRIPTION

We report the first case of orbital LVM extending intradurally through a bony defect in the medial orbital roof. A modified orbitozygomatic approach was used to successfully obliterate this lesion. Neurosurgical and ophthalmologic collaboration was used in the surgical management of this case.

CONCLUSIONS

This case highlights the importance of an interdisciplinary approach when managing infiltrative orbital LVMs, as both ophthalmologic and neurosurgical expertise were critical in the success of the surgery.

Orbital lymphatic-venous malformation with concomitant spontaneous orbital arteriovenous fistula: case report

The authors describe the case of an 11-year-old boy with no history of prior trauma, who experienced acute proptosis and visual loss while showering. Diagnostic carotid artery angiography revealed an orbital lymphatic-venous malformation (LVM) concomitant with an intraorbital arteriovenous fistula. The patient was treated with transvenous coil and N-butyl cyanoacrylate glue embolization, combined with direct percutaneous glue injection into the LVM followed by excision. There was good clinical and radiological response without recurrence at the 2-year follow-up. Diagnostic carotid angiography should be considered in cases of orbital LVM, as a concomitant arteriovenous fistula might be present in rare cases.

Eyelid arteriovenous malformation treated with pre-surgical embolization: A case report

Background Arteriovenous malformations are potentially serious vascular anomalies that are rarely encountered in the eyelid and require a multidisciplinary approach. Objectives We would like to describe the technical and clinical aspects related to the treatment of palpebral arteriovenous malformation with selective embolization, followed by surgical resection. Methods A 40-year-old patient presented with an isolated high-flow palpebral arteriovenous malformation. Transarterial embolization, using a liquid embolic agent (PHIL™), was performed in this patient. Results Angiographic and clinical follow-up revealed good results with clinical regression of the mass. Conclusion Although endovascular treatment of palpebral arteriovenous malformations is technically challenging, good functional and cosmetic result was achieved. Arteriovenous malformation embolization using PHIL™ seems to be very effective and makes subsequent surgical procedure safe and feasible. Level IV Evidence obtained from multiple time series with or without the intervention, such as case studies. Dramatic results in uncontrolled trials might also be regarded as this type of evidence.

Role of intralesional bleomycin sclerotherapy as the sole or adjunct treatment of superficial ocular adnexal lymphatic malformations

ObjectiveTo report the role of intralesional bleomycin as sole or adjunct therapy in the management of superficial ocular adnexal lymphatic malformations.DesignRetrospective study.ParticipantsThree patients/three eyes.MethodsRetrospective chart analysis of patients receiving intralesional bleomycin sclerotherapy as sole or adjunctive treatment for superficial ocular adnexal lymphatic malformations at a single tertiary level eye care institution.ResultsDegree of clinical regression of the lesions (graded by percentage) and resolution of symptoms and signs associated with the lesions.ConclusionsUse of intralesional bleomycin sclerotherapy appears to be an effective sole or adjunct treatment in the management of superficial ocular adnexal lymphatic malformations.

Combined approach to management of periocular arteriovenous malformation by interventional radiology and surgical excision

Periorbital arteriovenous malformations (AVMs) are congenital lesions that may cause significant morbidity such as amblyopia, cosmetic disfigurement, or chronic pain. Due to the rarity of these lesions, they are frequently misdiagnosed and treated inappropriately. We managed a 6-year-old girl with preseptal AVM by endovascular embolization followed by complete surgical excision after 2 days. She was previously diagnosed as capillary hemangioma and was being treated with intralesional steroid injections and oral propranolol. Neuroimaging revealed an AVM fed by the branches of both external and internal carotid arteries and drained by the superior ophthalmic vein. Endovascular embolization with glue followed by complete surgical excision of the lesion was done. The resultant cosmetic and functional outcome was gratifying. Diagnosis and management of periorbital AVM remain a challenge requiring a multidisciplinary approach involving interventional radiologist and trained oculoplastic surgeons. Combined endovascular embolization followed by surgical excision proved safe and effective.

CT-Guided Percutaneous Sclerotherapy for Low-Flow Retrobulbar Intraconal Venous Malformations

BACKGROUND AND AIMS

Until now, no study has focused exclusively on low-flow retrobulbar intraconal venous malformations (RIVMs) which may require treatment due to cosmetic defect, pain, and visual dysfunction. The treatment for RIVMs which surround the optic nerve remains challenging. This case series aimed to evaluate the technical feasibility, effectiveness, and safety of percutaneous sclerotherapy with polidocanol for low-flow RIVMs, using local anesthesia.

METHOD

This is a prospective, non-comparative, single-center, interventional case series. All patients signed informed consent forms. Seven patients with RIVMs were treated with percutaneous sclerotherapy with polidocanol/air foam using CT guidance. Primary endpoints are reduction in the volume of RIVMs and pain relief assessed by visual analog scale (VAS). Secondary endpoints are exophthalmos and recording adverse events obtained in clinical follow-up during outpatient visits.

RESULTS

Results revealed that the mean volume of RIVMs was decreased from 12.05 ± 6.35 cm³ preoperatively to 1.56 ± 0.43 cm³ postoperatively, (p = 0.005), with a mean decrease of 87.05%. The intraocular pressure was decreased from 14.19 ± 2.99 to 11.79 ± 1.25 mmHg, (p = 0.043). The mean VAS score was decreased from 3.43 ± 2.37 preoperatively to 1.29 ± 0.76 postoperatively, (p = 0.023). The exophthalmos score was decreased from 1.75 ± 0.27 to 1.34 ± 0.31 cm, (p = 0.005). All patients were satisfied with the treatment, which did not leave a postoperative scar.

CONCLUSIONS

The results of percutaneous intralesion injection of polidocanol for RIVMs are encouraging. The present results suggest that this method could be a safe and effective treatment option for patients with RIVMs.

Embolization of palpebral and orbito-frontal fistulas: technical and anatomical considerations in treating high-flow superficial skin lesions with liquid embolics

The treatment of palpebral and periorbital fistulas may be challenging due to the presence of multiple anastomosis with eloquent ophthalmic and intracranial vascular territories. Moreover, cosmetic and functional characteristics of this area pose unique challenges to open surgical approaches and endovascular therapy. We review the advantages and disadvantages of different liquid embolics in treating palpebral and periorbital fistulas as we describe three successfully treated cases. Moreover, we describe important anatomical landmarks that should be considered at the time of treatment of these lesions.

Arteriovenous Malformation of the Eyelid: Surgical Management and Histologic Study

A raised erythematous eyelid lesion that appeared in a 31-year-old man was diagnosed as an arteriovenous malformation (AVM), with confirmatory Doppler ultrasound demonstrating high arterial flow. Surgical excision, aided by electrocautery for extensive hemorrhage, resulted in an acceptable cosmetic result. Histopathology of the excised lesion showed collapsed capillary channels lined by endothelium. AVM is rarely encountered in the eyelid.

Urticarial reaction following endovascular embolization of an orbital arteriovenous malformation (AVM) with n-butyl cyanoacrylate (nBCA) glue

Orbital arteriovenous malformations (AVMs) are rare vascular lesions that may be managed with endovascular embolization followed by surgical resection. Embolization is often accomplished with n-butyl-2-cyanoacrylate (nBCA), which is considered to be a safe and effective liquid occlusive agent. Localized vascular inflammation has been associated with endovascular nBCA use in histopathologic studies, but reports of systemic hypersensitivity reactions following endovascular embolization with nBCA are rare. We present a case of a 26-year-old male who developed an intermittent systemic urticarial reaction without cardiopulmonary compromise beginning four weeks after nBCA embolization of an orbital AVM. Subsequent skin allergy testing performed by an allergist confirmed hypersensitivity to nBCA glue and the patient has since been successfully managed with daily oral antihistamines. Awareness of this rare potential complication of endovascular embolization with nBCA will aid in the counseling and management of patients with AVMs.

Normalization of Congenital Venous Stasis Retinopathy Following Sclerotherapy of a Macrocystic Lymphatic Malformation

The authors describe, for the first time to their knowledge, a case of a congenital macrocystic lymphatic malformation of the orbit with associated venous stasis retinopathy that acutely normalized after drainage and sclerotherapy of the lesion. Prenatal ultrasound revealed prominence of the left orbital soft tissue, and at birth, the patient was noted to have unilateral proptosis, tortuous retinal vessels, and intraretinal hemorrhages in all 4 quadrants in the left eye. MRI demonstrated a primarily intraconal, multiloculated, T2-hyperintense mass consistent with a lymphatic malformation. Ultrasound-guided cyst aspiration and sclerotherapy was performed, with subsequent improvement of the proptosis and resolution of the vessel tortuosity and intraretinal hemorrhages. Although venous stasis retinopathy is usually related to central retinal vein occlusion or carotid artery occlusive disease, any entity that increases orbital venous resistance can generate retinal venous dilation and intraretinal hemorrhages, including an orbital lymphatic malformation.

Cavernous venous malformation (cavernous hemangioma) of the orbit: Current concepts and a review of the literature

The cavernous venous malformation of the orbit, previously called cavernous hemangioma, is the most common primary orbital lesion of adults. Cavernous venous malformation occurs more often in women and typically presents in the fourth and fifth decades of life. It is a benign vascular malformation characterized by a well-defined capsule and numerous large vascular channels. The most common sign of cavernous venous malformation is progressive axial proptosis from the preferential involvement of the intraconal orbital space. Optic nerve damage and other signs of orbital pathology may be present, with a variable degree of visual impairment. The combination of ultrasound, computed tomography, and magnetic resonance imaging leads to an accurate diagnosis in the vast majority of cases. Surgical and nonsurgical treatments are required in case of symptomatic lesions, with a characteristic multidisciplinary management influencing optimal outcome. Orbitotomy represents the traditional surgical approach. Recently, the endoscopic transnasal approach to the orbital cavity has gained interest, representing a feasible and safe, less-invasive surgical technique for the management of cavernous venous malformation.

Low-Flow Arterialized Venous Malformations of the Orbit

PURPOSE

Orbital vascular malformations are classified by their hemodynamic properties, either high or low flow. Low-flow lesions may be simple venous, lymphatic, or combined lymphaticovenous malformations. The authors report a series of cases in which predominantly low flow, venous lesions were unexpectedly noted to have arterial feeders.

METHODS

A retrospective chart review of patients identified by the authors as having orbital varices with arterial components was conducted. The authors identified 7 such cases. After careful review, 2 cases were excluded due to inconclusive neuroradiographic findings. The authors review the clinical, radiologic, histopathologic, and surgical information from the remaining 5 cases and discuss their clinical significance.

RESULTS

All 5 cases were most consistent with variceal lesions: 3 as clinically distensible lesions and 2 as thrombosed lesions. Additional arterial feeder vessels were noted by angiography (3) or intraoperative visualization (2). The arterial contribution varied from faint vessels to distinct branches of the ophthalmic artery. Ages ranged from 13 to 61 years without predilection for gender. Treatments consisted of excision, embolization, and observation. Two poignant cases are highlighted: the first illustrating that an angiogram in isolation of its clinical picture can be misleading and result in treatment intervention with undue risk, and the second illustrating that inadequate treatment of unrecognized arterial components may contribute to recurrences.

CONCLUSIONS

Low-flow orbital variceal lesions may have less prominent, arterial components. This type of combined arterialized venous malformation is largely unrecognized in the ophthalmic literature. Correct identification of these lesions is critical in providing safe, effective, and durable treatment.

Management of Orbital and Periocular Vascular Anomalies

PURPOSE

To review the treatment modalities available to clinicians who treat orbital and periocular vascular anomalies, with a focus on newer approaches.

METHODS

The authors' experience, along with a literature review, was used to provide a concise summary of the available approaches to the treatment of periocular vascular anomalies. Emerging diagnostic tools and therapies are highlighted.

RESULTS

The treatment of orbital and periocular vascular anomalies, including vascular malformations and tumors, increasingly utilizes a multidisciplinary team and a combination of endovascular, percutaneous, and open surgical techniques.

CONCLUSIONS

A growing reliance on new instrumentation and tools in a team-oriented approach to treatment may lead to better results with improved visual function and cosmesis and with reduced risk of complications.

Vascular Steal Syndrome, Optic Neuropathy, and Foreign Body Granuloma Reaction to Onyx-18 Embolization for Congenital Orbito-Facial Vascular Malformation

A 34-year-old patient presented with a right orbito-facial mass since childhood, consistent with a congenital arteriovenous (AV) malformation. Prior to presentation, she had multiple incomplete surgical resections and embolizations with N-butyl acetyl acrylate and Onyx-18. The patient reported gradual, progressive vision loss shortly after Onyx-18 embolization. Five months after embolization, she presented with decreased vision, disfigurement and mechanical ptosis relating to a large subcutaneous mass affecting the medial right upper eyelid and forehead. Significant exam findings included a visual acuity of 20/400 (20/60 prior to embolization), an afferent pupillary defect, and optic disc pallor. MRI and angiography revealed a persistent AV malformation with feeders from the ophthalmic artery and an absent choroidal flush to the right eye. Pathology from surgical resection showed a significant foreign body giant cell reaction to the embolization material adjacent to the vessels. We suggest that an incomplete embolization with Onyx-18 may have caused vascular steal syndrome from the ophthalmic artery.

Anatomy of the Ophthalmic Artery: A Review concerning Its Modern Surgical and Clinical Applications

Anatomy of ophthalmic artery has been thoroughly studied and reviewed in many anatomical and surgical textbooks and papers. Issues of interest are its intracranial and extracranial course, its branches, its importance for vision, and its interaction with various intracranial pathologies. Improvement of our understanding about pathophysiology of certain diseases like aneurysm formation, central retinal artery occlusion, and retinoblastoma and also invention of new therapeutic modalities like superselective catheterization, intra-arterial fibrinolysis, and intra-arterial chemotherapy necessitate a reappraisal of its anatomy from a clinical point of view. The aim of this review is to examine clinical anatomy of ophthalmic artery and correlate it with new diagnostic and therapeutic applications.

Hybrid procedure for orbital venous malformation in the endovascular operation room

PURPOSE

To describe a hybrid procedure for orbital venous malformation in the endovascular operating room (EVOR).

METHODS

Five consecutive patients with venous malformation in the periocular and orbital region were included. All patients received a one-stage direct puncture venogram, image-guided glue injection, and surgical resection in the EVOR equipped with a biplane digital subtraction angiography system (BDSAS).

RESULTS

The mean age at the time of operation was 37.4 years (range, 22-69 years). The mean operative time was 193 min (range, 138-324 min). No intraoperative complications were noted. The mean follow-up duration was 18.8 months (range, 10-24 months). Three patients had complete removal of the vascular lesions. At the latest follow-up, no recurrence of symptoms related to the lesions was noted. All patients had an uneventful recovery and satisfactory outcome.

CONCLUSIONS

The hybrid procedure of orbital venous malformation in the EVOR is a novel application in ophthalmology. It is a safe and well-controlled procedure with real-time high-quality BDSAS surveillance to facilitate surgical resection. Its success requires collaboration between the interventional radiologist, the surgeon, and the ophthalmologist.

Immediate Reconstruction After Combined Embolization and Resection of Orbital Arteriovenous Malformation

Orbital arteriovenous malformations are rare congenital vascular anomalies that can cause eyelid distortion, proptosis, diplopia, and vision loss. The current treatment paradigm involves endovascular embolization followed by resection, with delayed reconstruction. The authors report 2 young adult patients with orbital arteriovenous malformations, who underwent embolization followed days to months later by resection with immediate soft tissue reconstruction. For both patients, the immediate outcome provided good functionality and cosmesis. The authors conclude that immediate reconstruction after embolization-resection of orbital arteriovenous malformations may facilitate early return of form and function for patients, improve quality of life, and potentially reduce the need for further reconstructive procedures.