Meningeal Feeders Research Articles

Angiographic Features of Meningiomas Predicting Extent of Preoperative Embolization.

Preoperative embolization is used as an endovascular adjunct to surgical resection of meningiomas. However, there is no standardized system to assess the efficacy or extent of embolization during the embolization procedure. We sought to establish a purely angiographic grading system to facilitate consistent reporting of the outcome of meningioma embolization and to characterize the anatomic and other features of meningiomas that predict the degree of devascularization achieved through preoperative embolization. We identified patients with meningiomas who underwent preoperative cerebral angiography and subsequent resection between 2015 and 2021. Demographic, clinical, and imaging data were collected in a research registry. We defined an angiographic devascularization grading scale as follows: grade 0 for no embolization, 1 for partial embolization, 2 for majority embolization, 3 for complete external carotid artery embolization, and 4 for complete embolization. Eighty consecutive patients were included, 60 of whom underwent preoperative tumor embolization (20 underwent angiography with an intention to treat but ultimately not embolization). Embolized tumors were larger (59.0 vs 35.9 cc; P = .03). Gross total resection, length of stay, and complication rates did not differ among groups. The distribution of arterial feeders differed significantly across tumors in a location-specific manner. Both the tumor location and the identity of arterial feeders were predictive of the extent of embolization. Anterior midline meningiomas were associated with internal carotid (ophthalmic, ethmoidal) supply and lower devascularization grades (P = .03). Tumors fed by meningeal feeders (convexity, falcine, lateral sphenoid wing) were associated with higher devascularization grades (P < .01). The procedural complication rate for tumor embolization was 2.5%. Angiographic outcomes can be graded to indicate the extent of tumor embolization. This system may facilitate consistency of reported angiographic results. In addition, arterial feeders vary in a manner predicted by tumor location, and these patterns correlate with typical degrees of devascularization achieved in those tumor locations.

Exoscopic resection of a parasagittal atypical meningioma.

This video demonstrates use of the Synaptive 3D exoscope to enhance complex meningioma resection. The patient was a 58-year-old female who presented with new-onset seizures. Workup revealed a parasagittal meningioma over the bilateral cortices. She was started on 750 mg of Keppra twice daily and tapered dexamethasone and discharged. MR venography demonstrated segmental occlusion of the superior sagittal sinus. She then underwent a diagnostic angiogram and tumor Onyx embolization of the bilateral middle meningeal artery feeders. She then underwent a craniotomy for meningioma resection using 3D exoscope guidance. She awoke with a stable examination in the intensive care unit and worked with physical therapy on postoperative day 1. The video can be found here: https://stream.cadmore.media/r10.3171/2023.10.FOCVID23164.

Endovascular embolization of high-grade cerebral dural arteriovenous fistulas - assessment of long-term recurrences.

Endovascular therapy has shown to be safe and effective for the treatment of cerebral dural arteriovenous fistulas; however, recurrence after complete occlusion is not uncommon, and the timing of recurrence remains unknown. A retrospective single-center cohort study was conducted from January 2005 to December 2020. Patients with high-grade (≥Borden II-Cognard IIB) dural arteriovenous fistulas treated with endovascular therapy were included in this study. Clinical and angiographic characteristics were collected for hospitalization and at follow-up. A total of 51 patients with a median age of 61 years were studied; 57% were female. High-flow symptoms related to the high-flow fistula were the most common presentation (67%), and 24% presented with intracranial hemorrhage. Transverse-sigmoid (26%) and cavernous (26%) sinuses were the most common dural arteriovenous fistula locations. A total of 40 patients (70%) had middle meningeal arterial feeders and 4 (7%) had deep cerebral venous drainage. The mean number of embolization procedures per patient was 1.4. Transarterial access was the most frequent approach (61%). Onyx alone was the most common embolic agent (26%). Complete occlusion rate was achieved in 46 patients (80.1%). Last mean radiographic follow-up time was 26.7 months for all 57 dural arteriovenous fistulas. Dural arteriovenous fistula recurrence after radiographic resolution at last treatment was seen in six cases (6/46, 13.1%). Mean time for recurrence was 15.8 months. Mean time of last clinical follow-up was 46.1 months for the 51 patients (100%). A total of 10 (20%) experienced any procedural complications, among which two (4%) became major thromboembolic events. Endovascular therapy is safe and effective for the treatment of high-grade dural arteriovenous fistulas. Given the significant recurrence rate of embolized dural arteriovenous fistulas even after 2 years, long-term angiographic follow-up might be needed.

Clinicopathologic Factors Associated with Tumor Necrosis after Preoperative Embolization of Meningiomas.

Preoperative embolization of meningiomas induces necrosis prior to surgery and facilitates resection. Lack of contrast enhancement on postembolization MRI correlates with pathological findings of necrosis and can be used to assess embolization efficacy. This study aimed to examine clinicopathologic factors associated with tumor necrosis after embolization. A total of 119 patients with intracranial meningioma who underwent 145 surgical resections between 2010 and 2019 at our institute were reviewed. Inclusion criteria for the study were preoperative embolization with trisacryl gelatin microspheres (Embosphere) or absorbable gelatine sponge (Gelfoam). Postembolization Gd-enhanced T1-weighted and angiographic imaging, and histopathologic examination results were reviewed to evaluate the effectiveness of embolization. In all, 66 patients satisfied the inclusion criteria. In total, 36 patients were embolized with Embosphere and 30 patients were embolized with Gelfoam. Patients embolized with Embosphere had a significantly higher necrosis rate (NR) than patients with Gelfoam (21% vs. 7.1%, P <0.01). The 36 Embosphere patients were analyzed regarding clinicopathologic factors associated with NR. Tumors in 12 patients were located in the parasagittal/falx region; these patients had a significantly lower NR compared with tumors in other locations (10.6% vs. 26.2%, P = 0.016). In all, 13 patients had feeders arising from only the middle meningeal artery (MMA), which was associated with a significantly higher NR (29.3% vs. 14.4%, P = 0.015). In total, 11 patients had meningeal feeders arising from internal carotid artery (ICA), which was associated with a significantly lower NR (9.0% vs. 26.3%, P <0.01). This study showed embolization agent, tumor location, and blood supply were important factors predicting necrosis after preoperative embolization.

Time-resolved 3D rotational angiography: display of detailed neurovascular anatomy in patients with intracranial vascular malformations

PurposeThe purpose of this pilot study was to demonstrate the applicability of time-resolved three-dimensional (3D) reconstructions from 3D digital subtraction angiography (DSA) rotational angiography (RA) datasets (four-dimensional (4D) DSA) to...

Secondary vein of Galen malformation with hydrocephalus: Treated with combined endovascular and endoscopic approach

Our goal is to describe a case of hydrocephalus in the setting of a Yasargil Type IV-C secondary vein of Galen malformation (VGM), treated with a combined endscopic and endovascular approach. We retrospectively reviewed the records of a patient admitted to the neurosurgical department hydrocephalus related to a secondary VGM. A 47 year old male, presents with 8 months of progressive headaches and gait ataxia. Imaging displays a triventricular hydrocephalus, a tectal AVM, and an aneurysmal dilation of the great vein of Galen. Angiography displays a tectal AVM supplied by bilateral posterior choroidals with drainage into the vein of Galen. In addition there were direct high-flow arteriovenous fistulas into the vein of Galen via meningeal feeders. The diagnosis of a Yasargil Type IV-C secondary VGM was made. The patient was treated via a combined endoscopic and endovascular approach. An endoscopic third ventriculostomy (ETV) was conducted for his hydrocephalus. He subsequently underwent a partial endovascular embolization of the left tentorial arterial feeder 1.5 months after his ETV. Post-operatively his hydrocephalus resolved, and his complex secondary VGM completely obliterated after a single partial embolization. Secondary VGMs with associated high-flow arteriovenous fistulas are rare. Our case provides a nice example a combined endoscopic and endovascular approach aimed at achieving cure of the hydrocephalus and the Yasargil Type IV-C secondary VGM. We were able to avoid the placement of shunt hardware via ETV treatment of the patient's hydrocephalus. Furthermore, our case displays the impact of partial embolization on control and potential cure of these complex vascular malformations.

Editorial: Embolization of meningiomas

First proposed in the 1970s, preoperative embolization of meningiomas has become an accepted adjunct to surgery. However, despite its widespread utilization, there is no strong evidence to support its effectiveness. With increasing experience, the true benefits of presurgical embolization have been questioned by some since the procedure is not devoid of potentially serious complications. Over the years, I have witnessed a wide variability among different surgeons in their utilization of preoperative embolization of meningiomas, an observation that underscores the lack of consensus about its benefits. Shah and coworkers provide a systematic review on the role of preoperative embolization of meningiomas. As they acknowledge, the quality of the information contained in their review is dependent upon the quality of the studies analyzed.1 Unfortunately, the majority of studies on this topic are single-center, retrospective series with their intrinsic biases. This, of course, limits the conclusions that we can draw from the authors’ study. Moreover, since Shah et al. strictly considered articles on presurgical embolization, some of the largest series (probably more representative of the actual complication rates) were excluded from analysis, although summarized in one of the accompanying tables. In the Discussion section, Shah and coworkers provide a thoughtful analysis of the pros and cons of preoperative meningioma embolization. I agree with the authors that preoperative embolization is safe and probably useful in the occlusion of distal meningeal feeders to selected very large or giant lesions. In these cases, preoperative embolization may “soften” the tumor and facilitate its exposure. Short of this indication, the role of presurgical embolization of meningiomas is questionable given the risk of complications and the lack of well-conducted studies to convince us about its advantages. Many of the studies analyzed by Shah et al. used polyvinyl alcohol (PVA) as the embolic agent of choice.1 At our institution, we also continue to use PVA for the very few and selected cases in which preoperative embolization is utilized. This particulate agent is not only effective in devascularizing the tumor, but also has an acceptable safety profile (as long as very small particles and “dangerous” feeders are avoided) and is much cheaper than newer agents. I don’t endorse meningioma embolization with Onyx, especially in cases like the one illustrated by Shah and coworkers in their Fig. 1. In my opinion, the risks of cranial neuropathies secondary to Onyx embolization of the ascending pharyngeal artery and proximal posterior branches of the middle meningeal artery far outweigh the potential benefits. With better understanding of the anatomy of the meningeal vessels, knowledge of “dangerous” anastomosis, and choice of right embolic agent and particle size, the overall risk of embolization is probably low but not negligible. The incidence and severity of complications are related to many factors that include the location of the lesion, its vascular supply, and the type of embolic agent utilized. Based on the data available in the literature, it is difficult to estimate the risk for the individual patient given the wide variability of these factors. Thus, the decision whether to consider preoperative meningioma embolization should be carefully pondered and the risks kept very low. (http://thejns.org/doi/abs/10.3171/2013.2.JNS121860)

新生児Dural Sinus Malformation

【目的】新生児dural sinus malformation（DSM）の１例を報告する．【症例】男児．妊娠28週にDSMと診断され，妊娠36週に帝王切開で出生した．出生時から心不全を認めたため，出生当日に血管内治療を行った．多数の髄膜動脈が後頭部の巨大なvenous pouchに動静脈シャントを形成しており，複数の流入血管を介して経動脈的塞栓術を行った．術後，心不全は改善した．その後は５ヵ月と８ヵ月時に経動脈的および経静脈的塞栓術をそれぞれ行い，動静脈シャントは著明に減少し，venous pouchも縮小した．１歳９ヵ月時点で軽度の発達遅延を認める以外に神経脱落症状なく成長している．【結語】DSMの新生児例に対し経動脈的塞栓術と経静脈的塞栓術を段階的に行い良好な結果が得られた．

Contralateral meningeal artery supply of paramedian meningiomas

Background When resecting at falcine or parasagittal portion of paramedian meningiomas, intraoperative hemostasis often is difficult despite effective management of ipsilateral meningeal arteries. We attribute such difficulties to meningeal artery blood supply from the contralateral side. We retrospectively studied feeding arteries from both sides in case of paramedian meningioma in terms of patient and tumor characteristics. Methods Forty-three patients with paramedian meningiomas underwent selective internal and external carotid angiography. We investigated how contralateral meningeal arterial feeders related to patient profiles and imaging, histopathologic, and immunohistochemical findings. Results Contralateral meningeal supply existed for 14 of 25 falcine meningiomas and 6 of 18 parasagittal meningiomas. Patients with contralateral feeders were 8.5 years younger than the others ( P = .027) and were more likely to have larger tumors ( P = .028). These were histopathologically malignant ( P = .048), while showing more proliferation followed by monoclonal antibody against the Ki-67 antigen index ( P = .012) and angiogenetic potential associated with vascular endothelial growth factor expression ( P = .0085). Conclusions Contralateral meningeal supply may reflect strong angiogenetic recruitment from rapid tumor growth followed by high expression of vascular endothelial growth factor. This angiographical feature may predict the aggressive growth of paramedian meningiomas.

Preoperative Embolization of Intracranial Meningiomas with Embosphere® Microspheres

To reduce intraoperative bleeding and to facilitate surgery by inducing tumor softening, a preoperative embolization of meningiomas is commonly recommended. We report on our experience with non-resorbable microspheres (Embosphere) in the preoperative endovascular embolization of 17 intracranial meningiomas. After adding contrast media to the particles sized 40-500 micron, the embolization process was followed under fluoroscopy. There was a good passage of microcatheters if high concentrations of particles were avoided. The obstruction of the tumor feeders by particles was accompanied by a regression of tumor blush in DSA. CT controls showed a diminished contrast accumulation of the tumors already 1-2 days after embolization. Histologically, Embosphere microspheres were easy detectable with all commonly used staining methods. Embolization triggered, microscopically detectable necrosis was found in 77 % of the tumors. The mean interval between embolization and tumor extirpation was 2.5 days. The average time required for tumor extirpation was 244 minutes, while the average blood loss was 749 ml. Our experiences show that Embosphere microspheres are effective embolic agents in obstructing meningeal feeders of preoperatively treated meningiomas.

脳動静脈奇形の塞栓術におけるｐｉｔｆａｌｌとその対策

As the embolization of AVMs is often an adjuvant therapy combined with surgical extirpation or radiosurgery, the goal is to optimize the outcome of the following procedure. As the natural history of AVMs predicts a relatively low rate of neurological injury, the combined therapeutic modalities should have a low complication rate. We report the perisurgical complications of 66 AVMs and discuss techniques to avoid complications. Of the 66 patients treated with endovascular embolization, 14 subsequently underwent surgical resection and 43 had radiosurgery. Four patients obtained total occlusion of their AVM by embolization alone and required no further treatment. In 48 patients, more than 70% of the nidus was occluded with embolization. We observed 3 permanent and 9 temporary complications. Four complications occurred immediately after embolization, due to overembolization or thromboembolism. Seven delayed complications occurred, possibly due to retrograde thrombosis or a chemical reaction to the glue. In 4 of the 14 cases without AVM obliteration following embolization and radiosurgery, meningeal feeders developed or recanalized after the treatment with absorbable particles. We recommend embolization prior to radiosurgery to treat all fistulous and meningeal feeders and packing of the nidus with non-absorbable embolic materials. In 10 cases, repeat embolization achieved further nidus reduction prior ro repeat radiosurgery. Intranidal aneurysms that pose a high risk of bleeding were also embolized. To avoid complications with embolization, the AVM angioarchitecture, hemodynamics and functional location should be well recognized. Complications can be reduced with preoperative functional imaging, superselective angiograms, appropriate selection of embolic materials, and appropriate selection of embolization targets. The priority of vessels to be embolized is dictated by the subsequent treatment. Agressive embolization of high-risk vessels or those that will cause abrupt hemodynamic changes should be avoided.

Embolization of Arteriovenous Malformations Prior to Radiosurgery

Embolization prior to radiosurgery is useful to reduce the AVM nidus for adequate planning for radiosurgery. In 37 cases we encountered, patients with the least radiosurgical effects had diffuse type nidus, where the feeders embolized with absorbable embolic materials had the possibility of recanalization. The main purpose of embolization is to prevent bleeding while the radiosurgical effects are being fully obtained. Thus, nidus embolization and the occlusion of fistulous feeders, meningeal feeders and intranidal aneurysms using permanent embolic materials are essential, since effective and successful embolization can increase the occlusion rate and shorten the period until complete occlusion following radiosurgery.

Embolisation of cerebral arteriovenous malformations to assure successful subsequent radiosurgery

This study investigated the angiographic changes in embolised arteriovenous malformations (AVMs) pre- and post-embolisation and preradiosurgery to clarify the usefulness of embolisation as a pretreatment for radiosurgery and the strategy of embolisation for the radiosurgical success. A total of 37 patients with cerebral AVMs treated over a period of 4 years was investigated. All the AVMs were embolised with N-butyl cyanoacrylate and 2 months later they were treated by radiosurgery. The size of AVM nidus reduced just following the embolisation (mean 21.9 ml to 3.9 ml). The angiogram taken in preparation for radiosurgery showed a further size reduction in the nidus of 16 AVMs, no change in 10 and regrowth in 11. In all the cases where size was reduced, the nidus was densely packed, while all the regrown AVMs were of the diffuse type. Five AVMs disappeared following radiosurgery, all of which were size-reduction or no-change cases. In conclusion, to achieve success in subsequent radiosurgery, nidus embolisation and the occlusion of fistulous and meningeal feeders are mandatory. Imprudent proximal feeder occlusion and the use of embolic materials with a risk of recanalisation should be avoided to prevent regrowth of the nidus, which may lead to errors in planning the radiosurgery to follow.

Effectiveness and Pitfall of Embolization of Cerebral Arteriovenous Malformations

We studied the course ofperisurgical complications of 66 AVMs and discussed the approapriate precautions. Of 66 patients with AVMs, 14 underwent postembolization surgical removal, and 43 underwent radiosurgery. Four patients were cured with total occlusion of their AVM by embolization alone. 48 patients achieved a more than 70% occlusion of the nidus. We observed 12 complications including 3 permanent and 9 temporary. Four complications occurred immediately after the embolization due to overembolization or thromboembolism, and 7 were observed several hours later which might have been caused by retrograde thrombosis or a chemical reaction to the glue. While presurgical embolization deepseated feeders must be embolized along with fistulous or high-flow feeders, 4 cases of 2nd embolization following radiosurgery showed that meningeal feeders developed or recanalized in cases embolized with absorbable particles. Thus, preradiosurgically, fistulous and meningeal feeders should be treated, and the nidus must be packed with embolic materials with no risk of recanalization. Successful nidus packing performed in 10 AVMs yielded a further nidus reduction before radiosurgery. The intranidal aneurysms which pose a high risk of rebleeding were also embolized. In order to avoid complications in the embolization of AVM, the angioarchitecture, hemodynamics and the relationship to brain function should be well recognized by preoperative functional imaging and superselective angiograms, and adequate embolic materials should be properly injected. As an embolization strategy, the priority of the target feeders should depend on the treatment to follow, and aggressive embolization of risky feeders or causing abrupt hemodynamic change should be avoided.

Embolization of Cerebral Arteriovenous Malformations to Enhance the Success of Subsequent Radiosurgery

We studied angiographic changes in embolized arteriovenous malformations (AVMs) by comparing pre- and postembolization angiograms and angiograms preceding radiosurgery. This study sought factors determining the usefulness of embolization as a pretreatment to enhance the success of subsequent radiosurgery. Thirty patients with cerebral AVMs treated in this manner over 4 years were studied. In these cases AVMs were embolized with cyanoacrylate and were treated with Gamma-knife radiosurgery. The mean size of the AVM nidus was reduced by a fraction of seven following embolization. The subsequent angiogram for planning radiosurgery showed further nidus reduction in 10 AVMs, no change in 12, and regrowth in 8. In all size-reduction cases the nidus was sufficiently packed, and 2 AVMs had thrombosed completely before radiosurgery. All the regrowing AVMs were of diffuse type; 6 were associated with already-developed leptomeningeal channels, and the remaining 3 were fed by newly sprouted meningeal feeders. Five AVMs disappeared following radiosurgery, all representing size-reduction or nochange cases. Analysis of cases with regrowth showed increased risk of that event with feeder occlusion of a multi-axially supplied AVM, lack of reduction of shunt flow, or remaining meningeal feeders. On the other hand, when embolization as pretreatment prior to radiosurgery succeeds in producing a small, compacted, plexiform nidus with slow shunt flow, it furthers the likelihood of successful radiosurgery. Nidus embolization and occlusion of fistulous and meningeal feeders are mandatory, while proximal feeder occlusion and use of embolic materials which risk recanalization should be avoided to prevent nidus regrowth.

Contribution of meningeal arteries to cerebral arteriovenous malformations

We studied 52 patients with cerebral arteriovenous malformations (AVMs) by selective angiography and found that half received supply from meningeal branches of the external carotid artery. The frequency of meningeal arterial contribution was significantly higher in superficial AVMs, especially in the temporal, parietal and occipital regions. Larger lesions and higher shunt with steal phenomena on angiography were other factors favouring a meningeal arterial contribution. Diffuse AVMs with pial arterial networks around the nidus commonly received meningeal blood supply. In the past, meningeal feeders have been thought to be congenital, but this study suggests that they may develop during growth of the AVM.

Atypical xanthoastrocytoma presenting as a meningioma

A 15-year-old boy was admitted to excision of a large exophytic right parietal tumor, which, on computed tomography scans and angiograms, revealed marked contrast-medium enhancement in infusion studies. Angiographic studies showed meningeal feeders, which suggested a meningioma. Computed tomography scans demonstrated extensive erosion of the skull, which indicated a slowly growing process. Pathologically it shared many features with pleomorphic xanthoastrocytomas, suggesting that neoplasia of the glia limitans may have a wide range of clinicopathological manifestations, including a favorable long-term prognosis.