Preoperative onyx embolization of meningiomas fed by the ophthalmic artery: a case series

Enhancing meningioma resection: a comprehensive study on the safety and effectiveness of Onyx™ presurgical embolization

Presurgical embolization (PE) has emerged as an interesting strategy to help turn brain tumor resection more amenable. This study aims to systematically review the safety and effectiveness of Onyx™ PE in meningioma resection. We followed Cochrane Collaboration and PRISMA for systematic review and meta-analysis, querying PUBMED, Cochrane Library, Web of Science, and Embase databases. Major complications were defined as other artery occlusion, visual deficits due to PE, or non temporary nerve damage, while minor included transitory conditions and others without clinical implications. A total of 186 patients were included, in which 120 were WHO grade I (80%), II (16%), and III (4%). Patient baseline characteristics and complications were distributed in groups without or with individual patient data analysis. Individual Patient Data Meta-Analysis (IPDMA) was performed on the last category, comprising 51 meningiomas that underwent Onyx™ PE. Among available data, 70%, 17%, and 13% were WHO grade I, II, and III, respectively. Considering all studies, tumor characteristics regarding grade underscored a certain homogeneity. Complications occurred at a rate of 9% (95% CI, 4 to 14%; I2 = 35%), with the rate of major complications significantly lower at only 1% (95% CI, 0 to 3%; I2 = 32%), whereas of minor complications was 7% (95% CI, 3 to 10%; I2 = 0%). Mean surgery blood loss was 668.7 (95% CI, 534.9 to 835.8; I2 = 0%) in IPDMA. Onyx™ PE is promising for safer surgical meningioma resection, despite limitations. Further studies are required to validate efficacy, enhance patient selection, and refine techniques.

Outcomes of Preoperative Transophthalmic Artery Embolization of Meningiomas: A Systematic Review with a Focus on Embolization Agent

BACKGROUND

Transophthalmic artery embolization of intracranial meningiomas is thought to be associated with a high complication risk.

PURPOSE

With advances in endovascular techniques, we systematically reviewed the current literature to improve our understanding of the safety and efficacy of transophthalmic artery embolization of intracranial meningiomas.

DATA SOURCES

We performed a systematic search using PubMed from inception until August 3, 2022.

STUDY SELECTION

Twelve studies with 28 patients with intracranial meningiomas embolized through the transophthalmic artery were included.

DATA ANALYSIS

Baseline and technical characteristics and clinical and safety outcomes were collected. No statistical analysis was conducted.

DATA SYNTHESIS

The average age of 27 patients was 49.5 (SD, 13) years. Eighteen (69%) meningiomas were located in the anterior cranial fossa, and 8 (31%), in the sphenoid ridge/wing. Polyvinyl alcohol particles were most commonly (n = 8, 31%) used to preoperatively embolize meningiomas, followed by n-BCA in 6 (23%), Onyx in 6 (23%), Gelfoam in 5 (19%), and coils in 1 patient (4%). Complete embolization of the target meningioma feeders was reported in 8 (47%) of 17 patients; partial embolization, in 6 (32%); and suboptimal embolization, in 3 (18%). The endovascular complication rate was 16% (4 of 25), which included visual impairment in 3 (12%) patients.

LIMITATIONS

Selection and publication biases were limitations.

CONCLUSIONS

Transophthalmic artery embolization of intracranial meningiomas is feasible but is associated with a non-negligible complication rate.

Liquid Embolic Agents for Endovascular Embolization: A Review

Endovascular embolization (EE) has been used for the treatment of blood vessel abnormalities, including aneurysms, AVMs, tumors, etc. The aim of this process is to occlude the affected vessel using biocompatible embolic agents. Two types of embolic agents, solid and liquid, are used for endovascular embolization. Liquid embolic agents are usually injectable and delivered into the vascular malformation sites using a catheter guided by X-ray imaging (i.e., angiography). After injection, the liquid embolic agent transforms into a solid implant in situ based on a variety of mechanisms, including polymerization, precipitation, and cross-linking, through ionic or thermal process. Until now, several polymers have been designed successfully for the development of liquid embolic agents. Both natural and synthetic polymers have been used for this purpose. In this review, we discuss embolization procedures with liquid embolic agents in different clinical applications, as well as in pre-clinical research studies.

Orbital Venous Malformation Excision after Transcaruncular Embolization with Onyx

Orbital venous malformations are low-flow lesions resulting from vascular dysgenesis during development. Patients may present with vision loss, proptosis accentuated by Valsalva, and/or painful spontaneous thrombosis. The preferred treatment for symptomatic lesions is embolization combined with excision. A 34-year-old male presented to our institution from an outside emergency department with a diagnosis of presumed idiopathic orbital inflammation. For the prior month, he had been experiencing left orbital pressure, subjective eye bulging, and both diplopia and blurry vision when in peripheral gaze or when bending over. Despite initial improvement with steroids, his symptoms recurred with tapering. Visual acuity was reduced to 20/25, but pupils and motility remained normal. Biopsy demonstrated a vascular lesion characterized by fibroadipose tissue with histologically unremarkable blood vessels, and cerebral arteriography showed no high-flow components. A diagnosis of orbital venous malformation was made. He then underwent intraoperative angiography and Onyx embolization followed by excision via a transcaruncular approach. Two prior reports have described the use of Onyx in venolymphatic malformations. This report highlights a detailed approach to defining flow characteristics pre- and intraoperatively and expands upon our understanding of the use of Onyx for such cases.

Preoperative Devascularization of Choroid Plexus Tumors: Specific Issues about Anatomy and Embolization Technique

(1) Background: Surgical treatment of choroid plexus tumors is challenging, burdened by a notable risk of bleeding. Neoadjuvant chemotherapy and preoperative embolization have been attempted, with encouraging results; however, the consensus on these procedures is lacking. (2) Methods: We present a case of a 10-month-old girl who underwent preoperative embolization of a hemorrhagic choroid plexus carcinoma of the lateral ventricle via the anterior choroidal artery, followed by total resection. (3) Results: The endovascular procedure was successfully completed, despite the rectification of the anterior choroidal artery associated with the absence of flow proximal to the plexal point. Minimal bleeding was observed during resection and the patient remained neurologically intact. (4) Conclusions: The time from entrance to exit in the anterior choroidal artery should be monitored and regarded as a potential 'occlusion time' in this specific group of patients. Nevertheless, our case supports the feasibility and effectiveness of preoperative embolization of a choroid plexus carcinoma of the lateral ventricle via the anterior choroidal artery, without complications. Furthermore, we suggest the use of a fast-embolic agent, such as N-butyl cyanoacrylate glue, as the preferred agent for this specific pathology and patient population.

Efficacy of endovascular intratumoral embolization for meningioma: assessment using dynamic susceptibility contrast-enhanced perfusion-weighted imaging

BACKGROUND

In preoperative embolization for intracranial meningioma, endovascular intratumoral embolization is considered to be more effective for the reduction of tumorous vascularity than proximal feeder occlusion. In this study, we aimed to reveal different efficacies for reducing tumor blood flow in meningiomas by comparing endovascular intratumoral embolization and proximal feeder occlusion using dynamic susceptibility contrast-enhanced perfusion-weighted imaging (DSC-PWI).

METHODS

28 consecutive patients were included. DSC-PWI was performed before and after embolization for intracranial meningiomas. Normalized tumor blood volume (nTBV) of voxels of interest of whole tumors were measured from the DSC-PWI data before and after embolization. ΔnTBV% was compared between the cases that received intratumoral embolization and proximal feeder occlusion.

RESULTS

ΔnTBV% in the intratumoral embolization group (42.4±29.8%) was higher than that of the proximal feeder occlusion group (15.3±14.3%, p=0.0039). We used three types of embolic materials and ΔnTBV% did not differ between treatments with or without the use of each material: 42.8±42.4% vs 28.7±20.1% for microspheres (p=0.12), 36.1±20.6% vs 28.1±41.1% for n-butyl cyanoacrylate (p=0.33), and 32.3±37.3% vs 34.1±19.0% for bare platinum coils (p=0.77).

CONCLUSIONS

The flow reduction effect of intratumoral embolization was superior to that of proximal feeder occlusion in preoperative embolization for intracranial meningioma in an assessment using DSC-PWI.

Detailed Arterial Anatomy and Its Anastomoses of the Sphenoid Ridge and Olfactory Groove Meningiomas with Special Reference to the Recurrent Branches from the Ophthalmic Artery

BACKGROUND AND PURPOSE

Detailed arterial anatomy of the sphenoid ridge and olfactory groove meningiomas is complicated due to the fine angioarchitecture and anastomoses between each feeder. Herein, we present details of the arterial anatomy and the relationships of feeders in these lesions.

MATERIALS AND METHODS

This study included 20 patients admitted to our department between April 2015 and March 2020. Conditions of subjects consisted of 16 sphenoid ridge meningiomas and 4 olfactory groove meningiomas. We mainly analyzed arterial anatomy using 3D rotational angiography and slab MIP images of these lesions. We also analyzed the anastomoses of each feeder.

RESULTS

We found that 19 (95%), 15 (75%), and 15 (75%) lesions had feeders from the ophthalmic, internal carotid, and external carotid arteries, respectively. As feeders from the ophthalmic artery, recurrent meningeal arteries were involved in 18 lesions (90%). Fifteen lesions (75%) had anastomoses between each feeder.

CONCLUSIONS

Most of the meningiomas in the sphenoid ridge and olfactory groove had feeders from the ophthalmic and internal carotid arteries. There were various anastomoses between each feeder. This is the first report to demonstrate the detailed arterial anatomy and frequency of recurrent branches from the ophthalmic artery and their anastomoses using detailed imaging techniques.

Transarterial Embolization of a Parasellar Hypervascular Tumor

Embolization of hypervascular tumors has been widely performed for over four decades, particularly for preoperative meningioma. Several benefits of preoperative embolization have been reported, including reduced blood loss, surgical time and surgical complications, and improved outcomes. However, the technical details of both embolization and surgical procedures, and lesions widely vary. Thus, the actual benefits of preoperative embolization have not been clarified by prospective randomized studies. Procedure-related complications due to embolization developed in 3%-12% in previous studies. For parasellar lesions, both surgical resection and embolization have a higher risk of complication than for lesions at other locations because of the complicated neurovascular anatomy in the parasellar area. Therefore, close attention should be paid to the detailed vascular anatomy, embolic material, and related information for embolization and resection in individual cases to improve patient outcomes.

A Case of Anterior Cranial Fossa Dural Arteriovenous Fistula with Transient Ocular Movement Disorder after Embolization

Objective

We report a case of anterior cranial fossa dural arteriovenous fistula (dAVF) in which ocular movement was impaired after Onyx embolization from the ophthalmic artery (OphA).

Case Presentation

A 76-year-old male was admitted to our hospital for treatment of an incidentally found anterior cranial fossa dAVF. Onyx was injected from the right anterior ethmoidal artery (AEA) to close the shunt. Onyx refluxed to the third portion of the OphA to make a plug, but was unable to reach the venous side beyond the shunt; therefore, a small shunt remained. Although his visual acuity and field were normal, vertical diplopia developed after embolization and disappeared 1 month later. Diplopia worsened when the patient tilted his head to the right. Neuro-ophthalmological examination confirmed right superior oblique muscle impairment. The cause of diplopia was considered to be ischemic injury of the superior oblique muscle associated with embolization of the AEA, which provides nutrients to the superior oblique muscle and trochlear nerve.

Conclusion

Embolization from the OphA beyond the third portion may cause external ophthalmoplegia, although it may heal spontaneously.

Embryology and anatomical variations of the ophthalmic artery

PURPOSE

The ophthalmic artery (OA) has one of the most complex anatomy and the most fascinating embryological development.

METHODS

The complexity of the embryologic development of the OA resides in the implication of three different embryological systems: the carotid system, the stapedial system, and the ventral pharyngeal system.

RESULTS

This explains very well the numerous variations in origin of the OA and the importance of vascular anastomoses developed with branches of the external carotid artery and with the middle meningeal artery.

CONCLUSION

In this review, authors propose a comprehensive description of different hypotheses on the embryologic development of the OA and, in a second part, explain all anatomical variations and clinical implications of this artery.

Preoperative embolization of skull base meningiomas: current indications, techniques, and pearls for complication avoidance

Skull base meningiomas are technically challenging tumors to treat because of their deep vascular supply that can preclude early devascularization during resection. Preoperative embolization of these arterial feeders is thought to decrease blood loss and facilitate resection; however, given the complex and varied anatomy of these skull base lesions, preoperative embolization is not without risk. It is essential for both endovascular and skull base neurosurgeons to understand these risks in light of the potential benefits. The authors review the vascular anatomy of skull base meningiomas, indications for preoperative devascularization, endovascular techniques, and published results regarding embolization of these lesions.

Improving Forward Infusion Pressure during Brain Tumor Embolization with the Double Catheter and Coil Technique

Endovascular embolization or embosurgery of brain tumors can be used to reduce neoplasm vascularity prior to surgical resection. Two challenges with embosurgery relate to insufficient perfusion pressure into the tumor and inadvertent escape of infused agents into parenchymal branches of the adjacent brain. This report describes a multi-catheter and coil technique to improve tumor perfusion and prevent reflux into normal branches.

The maxillary artery and its variants: an anatomical study with neurosurgical applications

BACKGROUND

The maxillary artery (MA) has gained attention in neurosurgery particularly in cerebral revascularization techniques, intracranial endonasal approaches and endovascular procedures.

OBJECTIVES

To describe and illustrate the anatomy of the MA and its neurosurgical importance in a detailed manner.

METHODS

Six cadaveric heads (12 MAs) were injected with latex. The arteries and surrounding structures were dissected and studied using microsurgical techniques. The dimensions, course and branching patterns of the MA were recollected. In addition, 20 three-dimensional reconstruction CT head and neck angiograms (3D CTAs) of actual patients were correlated with the cadaveric findings.

RESULTS

The MA can be divided in three segments: mandibular, pterygoid and pterygopalatine. Medial and lateral trunk variants regarding its course around the lateral pterygoid muscle can be found. The different branching patterns of the MA have a direct correlation with the course of its main trunk at the base of the skull. Branching and trunk variants on one side do not predict the findings on the contralateral side.

CONCLUSION

In this study the highly variable course, branching patterns and relations of the MA are illustrated and described in human cadaveric heads and 3D CTAs. MA 3D CTA with bone reconstruction can be useful preoperatively for the identification of the medial or lateral course variants of this artery, particularly its pterygoid segment, which should be taken into account when considering the MA as a donor vessel for an EC-IC bypass.

Preoperative Embolization of Extra-axial Hypervascular Tumors with Onyx

OBJECTIVE

Preoperative endovascular embolization of intracranial tumors is performed to mitigate anticipated intraoperative blood loss. Although the usage of a wide array of embolic agents, particularly polyvinyl alcohol (PVA), has been described for a variety of tumors, literature detailing the efficacy, safety and complication rates for the usage of Onyx is relatively sparse.

MATERIALS AND METHODS

We reviewed our single institutional experience with pre-surgical Onyx embolization of extra-axial tumors to evaluate its efficacy and safety and highlight nuances of individualized cases.

RESULTS

Five patients underwent pre-surgical Onyx embolization of large or giant extra-axial tumors within 24 hours of surgical resection. Four patients harbored falcine or convexity meningiomas (grade I in 2 patients, grade II in 1 patient and grade III in one patient), and one patient had a grade II hemangiopericytoma. Embolization proceeded uneventfully in all cases and there were no complications.

CONCLUSION

This series augments the expanding literature confirming the safety and efficacy of Onyx in the preoperative embolization of extra-axial tumors, underscoring its advantage of being able to attain extensive devascularization via only one supplying pedicle.

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.

Safety and efficacy of medium-sized particle embolisation for skull-base meningioma

AIM

To determine the effectiveness and safety of preoperative tumour embolisation for skull-base meningiomas via external carotid artery (ECA) feeders using medium-sized (150-250 μm) polyvinyl alcohol (PVA) particles.

MATERIALS AND METHODS

This study included 114 consecutive patients with skull-base meningiomas who underwent preoperative tumour embolisation using medium-sized PVA particles from January 2004 to December 2013. Tumours were categorised according to feeding artery as follows: type 1, tumour staining at ECA angiography only; type 2, tumour staining at both the ECA and internal carotid artery (ICA) angiography; or type 3, little or no tumour staining at ECA angiography. The effectiveness was based on the percent reduction in the enhanced area: >75% was considered effective, 25-75% was considered partially effective, and <25% was considered ineffective.

RESULTS

Tumour embolisation was performed in patients with dominant feeding vessels originating from the ECA. Procedural-related complications occurred in two (1.8%) patients. Post-procedural MRI images were available for 51 patients, which revealed effective embolisation in only 13 (25.5%) patients. Identification of an ICA feeding vessel was associated with ineffective embolisation (p=0.011). Effective embolisation was associated with low estimated blood loss during surgery.

CONCLUSION

ECA embolisation using medium-sized PVA is ineffective in patients in whom a definitive ICA feeding vessel was identified, even if preprocedural angiography showed that the dominant feeder originated from the ECA. When the risks of surgical morbidity and mortality are expected to be high, ICA feeder embolisation should also be considered.

Transarterial Onyx Embolization of an Orbital Solitary Fibrous Tumor

Solitary fibrous tumor (SFT) is an uncommon mesenchymal neoplasm sometimes found in the orbit. We report a case of an aggressive orbital SFT with enlarged feeding vessels that was successfully resected immediately after transarterial embolization with Onyx (ethylene vinyl alcohol copolymer). To our knowledge, this is the first report showing the histopathology of Onyx embolization material in an orbital SFT.

Controversies in the role of preoperative embolization in meningioma management

The role of preoperative embolization in meningioma management remains controversial, even though 4 decades have passed since it was first described. It has been shown to offer benefits such as decreased blood loss and "softening of the tumor" during subsequent resection. However, the actual benefits remain unclear, and the potential harm of an additional procedure along with the cost of embolization have limited its use to a small proportion of the meningiomas treated. In this article the authors retrospectively reviewed their experience with preoperative embolization of meningiomas over the previous 6 years (March 2007-March 2013). In addition, they performed a MEDLINE search using a combination of the terms "meningioma," "preoperative," and "embolization" to analyze the indications, embolizing agents, timing, and complications reported during preoperative embolization of meningiomas. In this retrospective review, 18 cases (female/male ratio 12:6) were identified in which endovascular embolization was used prior to resection of an intracranial meningioma. Craniotomy for tumor resection was performed within 4 days after endovascular embolization in all cases, with an average time to surgery of 1.9 days. The average duration of surgery was 4 hours and 18 minutes, and the average blood loss was 574 ml, with a range of 300-1000 ml. Complications following endovascular therapy were identified in 3 (16.7%) of 18 cases, including one each of transient hemiparesis, permanent hemiparesis, and tumor swelling. The literature review returned 15 articles consisting of a study population greater than 25 patients. No randomized controlled study was found. The use of small polyvinyl alcohol particles (45-150 μm) is more effective in preoperative devascularization than larger particles (150-250 μm), but is criticized due to the higher risk of complications such as cranial nerve palsies and postprocedural hemorrhage. Time to surgery after embolization is inconsistently reported across the articles, and conclusions on the appropriate timing of surgery could not be drawn. The overall complication rate reported after treatment with preoperative meningioma embolization ranges from as high as 21% in some of the older literature to approximately 6% in recent literature describing treatment with newer embolization techniques. The evidence in the literature supporting the use of preoperative meningioma embolization is mainly from case series, and represents Level III evidence. Due to the lack of randomized controlled clinical trials, it is difficult to draw any significant conclusions on the overall usefulness of preoperative embolization during the management of meningiomas to consider it a standard practice.

Contemporary endovascular embolotherapy for meningioma

Preoperative endovascular tumor embolization has been used for 40 years. Meningiomas are the most common benign intracranial tumor in which preoperative embolization has been most extensively described in the literature. Advocates of embolization report that it reduces operative blood-loss, and softens the tumor, thus making surgery safer and easier. Opponents suggest that it adds additional risk and cost for patients without controlled studies showing conclusive benefit. The literature suggests a 3 to 6% neurological complication rate related to embolization. The combined external and internal carotid artery blood supply and complex anastomoses of the meninges can make embolization challenging. Positive outcomes require thorough knowledge of the pertinent vascular anatomy, familiarity with the neurovascular equipment and embolics, and meticulous technique. There remains debate on several aspects of embolization, including tumors most appropriate for embolization, embolic agent of choice, ideal size of embolic, and the choice of vessel(s) to embolize. This detailed review of pertinent vascular anatomy, embolization technique, results, and complications should allow practitioners to maximize treatment outcomes in this setting.

Preoperative embolization of choroid plexus papilloma with Onyx via the anterior choroidal artery: technical note

INTRODUCTION

Total surgical resection is the treatment of choice for choroid plexus tumors. However, the hypervascular nature of such lesions imposes challenges to the surgical treatment. Preoperative embolization for intracranial tumors has been widely used in an attempt to reduce blood loss, but rarely with choroid plexus tumors.

CASE REPORT

We describe the first case of preoperative embolization of choroid plexus papilloma with Onyx via the anterior choroidal artery. The procedure underwent without any complications and surgical treatment was possible with minimal blood loss.

DISCUSSION

Embolization of choroid plexus tumors via anterior choroidal artery is potentially dangerous, but following a meticulous technique, it can be used as a safe and effective preoperative procedure.