Middle meningeal artery embolization treatment of nonacute subdural hematomas in the elderly: a multiinstitutional experience of 151 cases

Complications of Middle Meningeal Artery Embolization: A Systematic Review and Meta-Analysis

BACKGROUND

Middle meningeal artery embolization (MMAE) is an established treatment option for chronic subdural hematoma. The aim of this systematic review and meta-analysis was to establish estimates of the pooled incidence for complications following MMAE.

METHODS

PubMed, Embase, and Cochrane were searched for studies reporting complications following MMAE through January 2023. A random effects model was used to calculate the pooled incidence of complications stratified based on whether studies excluded patients with comorbidities. Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist was followed.

RESULTS

A final 34 studies containing 921 patients undergoing MMAE were included that reported 35 complications. Neurological complications were reported in 7 studies with an overall pooled incidence of 3.8% (95% confidence interval [CI]: 2.6%-5.5%). Across these studies, there was a pooled incidence of 4.9% (95% CI: 2.9%-8.0%), 3.0% (95% CI: 1.7%-5.3%), and 2.1% (95% CI: 0.4%-9.7%) in studies that did not exclude, did not mention, or excluded patients with comorbidities, respectively. Similarly, 7 studies reported cardiovascular complications with an overall pooled incidence of 3.6% (95% CI: 2.4%-5.4%), 4 studies reported infectious complications with an overall pooled incidence of 2.9% (95% CI: 1.9%-4.5%), and 3 studies reported for miscellaneous complications with an overall pooled incidence of 3.1% (95% CI: 2.0%-4.8%). Further subgroup analysis revealed the pooled incidence of cardiovascular complications was 3.2% (95% CI: 1.7%-6.1%) in studies that did not exclude patients with comorbidities, 4.1% (95% CI: 2.3%-7.1%) in studies that did not specify the exclusion of such patients, and 1.8% (95% CI: 0.2%-11.5%) in studies that excluded these patients. Similarly, the incidence of infectious complications was 3.3% (95% CI: 1.7%-6.2%), 2.7% (95% CI: 1.5%-5.0%), and 1.8% (95% CI: 0.2%-11.5%) across these groups, respectively. Miscellaneous complications were reported at 4.0% (95% CI: 2.2%-7.2%), 2.3% (95% CI: 1.1%-4.6%), and 3.1% (95% CI: 0.9%-10.1%), respectively.

CONCLUSIONS

The published literature suggests that MMAE is a generally well-tolerated procedure with a low risk of significant complications.

Middle meningeal artery embolization for recurrent subdural hematoma in an extra-intracranial anastomosis patient on anticoagulant medication: A case report

Symptomatic chronic subdural hematoma (cSDH) is amongst the most frequent neurological diseases with an upward trend due to an aging society and development in the field of anticoagulation therapies. Lately, subgaleal drainages and middle meningeal artery (MMA) embolization have been introduced to the standard armamentarium as treatment options for cSDH patients. Vascular anomalies, such as internal carotid artery (ICA) occlusion with spontaneous extra-intracranial anastomoses, usually lead to forfeiting embolization treatment from patients. This report presents a case of a 67-year-old male with a repeated recurrence of cSDH in conjunction with a history of middle cerebral artery territory stroke and consecutive platelet inhibition therapy. The patient was initially treated with a burr hole plus subgaleal and subdural drainage upon revision surgery. Due to repeated recurrence, MMA embolization was considered, even though an extra-intracranial anastomosis was present on angiography. The patient was deemed to be fully recovered three months after intervention and no further intervention was needed. We can conclude that MMA embolization is a feasible option also in patients with recurrent cSDH after territorial infarction secondary to ICA occlusion with present extra-intracranial anastomoses.

One-Stage Burr Hole Surgery and Middle Meningeal Arterial Embolization for Treating Chronic Subdural Hematoma in a Hybrid Operative Angiography Suite

BACKGROUND

Chronic subdural hematoma (CSDH) is a prevalent neurosurgical condition that is known to recur and that leads to unfavorable clinical outcomes. Middle meningeal artery embolization (MMAE) has emerged as an alternative treatment to prevent recurrence. This study investigated the efficacy of combined 2 therapies in a hybrid operative suite for high-risk patients.

METHODS

This retrospective review provides evidence for the indications and benefits of one-stage combined therapy in a hybrid neurovascular operative suite. The procedures include burr hole craniostomy, irrigation, and drainage followed by adjuvant MMAE at the lesion site. Subsequently, routine cone beam computed tomography is conducted after the whole process.

RESULTS

Five patients with symptomatic CSDH and mass effect were enrolled in this study. Among them, 3 patients had undergone burr hole surgery previously but experienced hematoma recurrence. Two patients presented with a history of recent cardiac stent placement due to coronary artery disease, precluding the cessation of antiplatelet or anticoagulant therapy. All patients experienced symptom resolution and demonstrated no evidence of CSDH recurrence during the follow-up period.

CONCLUSIONS

In our initial case experiences, one-stage burr hole surgery and adjuvant MMAE for treating chronic subdural hematoma in a hybrid operative angiography suite could be a feasible and effective treatment modality.

Newer treatment paradigm improves outcomes in the most common neurosurgical disease of the elderly: a literature review of middle meningeal artery embolization for chronic subdural hematoma

Chronic subdural hematoma (cSDH) is one of the most prevalent neurosurgical diseases, especially in the elderly. Yet, its incidence is predicted to increase further, paralleling the growth of the geriatric population. While surgical evacuation is technically straightforward, it is associated with significant morbidity and mortality. In fact, 30% of patients are expected to have hematoma recurrence and to need repeat surgical evacuation, and 20% of patients are expected to lose independence and require long-term care. A pathophysiology more complex than originally presumed explains the disappointing results observed for decades. At its core, the formation of microcapillaries and anastomotic channels with the middle meningeal artery (MMA) perpetuates a constant cycle resulting in persistence of hematoma. The rationale behind MMA embolization is simple: to stop cSDH at its source. Over the last few years, this "newer" option has been heavily studied. It has shown tremendous potential in decreasing hematoma recurrence and improving neurological outcomes. Whether combined with surgical evacuation or performed as the only treatment, the scientific evidence to its benefits is unequivocal. Here, we aimed to review cSDH in the elderly and discuss its more recent treatment options with an emphasis on MMA embolization.

Adjunct Middle Meningeal Artery Embolization Versus Surgery for Chronic Subdural Hematoma: A Systematic Review and Meta-Analysis

BACKGROUND

The procedure of middle meningeal artery embolization (MMAE) has emerged as a minimally invasive therapy for chronic subdural hematoma (CSDH). Previous studies comparing MMAE with conventional treatment for CSDH did not differentiate primary/upfront, adjunct, or rescue MMAE, and included both conservative and surgical treatment in the comparison group. We conducted a systematic review and meta-analysis to compare outcomes after adjunct MMAE (MMAE combined with surgical evacuation) versus surgery alone for CSDH.

METHODS

PubMed, Embase, Cochrane, Web of Science, and Scopus databases were searched to August 2023. Primary outcomes were treatment failure and reoperation. Secondary outcomes were complications, mortality, length of hospital stay, 30-day readmission, and follow-up modified Rankin Scale (mRS) > 2. Additional data from our institution was included.

RESULTS

12 published studies and our data yielded 57,165 patients, of whom 1,065 (1.9%) received adjunct MMAE and 56,100 (98.1%) surgery alone. Compared to surgery alone, adjunct MMAE was associated with lower rates of treatment failure (OR = 0.43 [0.23-0.83], p = 0.01), reoperation (OR = 0.45 [0.22-0.90], p = 0.02), and 30-day readmission (OR = 0.50 [0.34-0.73], p < 0.001). Length of hospital stay (MD = 2.49 [-0.51, 5.49], p = 0.10) was non-significantly longer in the adjunct MMAE group. Both groups had comparable rates of treatment-related complications (OR = 0.89 [0.52-1.53], p = 0.67), mortality (OR = 1.05 [0.75-1.46], p = 0.78), and follow-up mRS > 2 (OR = 0.91 [0.39-2.12], p = 0.83).

CONCLUSIONS

Adjunct MMAE reduces treatment failure, reoperation, and readmission rates without increasing morbidity and mortality. MMAE may be considered as an adjunct to surgical evacuation to reduce CSDH recurrence. Randomized trials will further establish the evidence for adjunct MMAE and its role in the management of CSDH.

Middle Meningeal Artery Embolization for Chronic Subdural Hematoma: A Bibliometric Analysis

BACKGROUND

Middle meningeal artery embolization (MMAE) is an endovascular technique that has been rapidly adopted in the management of chronic subdural hematoma (cSDH), with numerous positive results across the literature. This study aimed to summarize the body of original research published on MMAE for the treatment of cSDH through bibliometric methods.

METHODS

The Web of Science, Science Citation Index Expanded database was queried on October 1, 2024 for articles related to MMAE for cSDH. The title, abstract, authors, publication year, journal, keywords, institution of first author, author keywords, and citations of studies were extracted for bibliometric analysis. Bibliometric visualizations were performed using VOSviewer version 1.6.20 and other visualizations were made in Graphpad Prism version 9.4.0. Overlay visualizations depicting average year of article output were selectively constructed to further elucidate trends in authorship.

RESULTS

The study retrieved 198 publications on MMAE to be included in analysis. There was an exponential increase in both the number of published studies and the number of citations over the timeframe. The author, country, institution, and journal that contributed the most to the field were Christopher S. Ogilvy, the United States, Harvard Medical School, and WORLD NEUROSURGERY, respectively. The most recent groupings on keyword analysis as of 2023 include "subdural," "liquid embolic material," "embolic," and "hemorrhage".

CONCLUSIONS

As the popularity of MMAE and power of studies related to the technique continues to rise, we hope that this analysis can continue to guide clinicians and researchers on growing areas of interest and academic hotspots of collaboration.

Organization of the Middle Meningeal Artery in a Sample of Black South African Population: Clinical Correlates

BACKGROUND

The middle meningeal artery (MMA) is the leading supplier of the cranial dura and serves as a donor blood channel in craniotomy and cerebrovascular bypass procedures. However, the complex embryology of the MMA and population differences give rise to several anatomic variations that are of great importance in head injuries pertaining to the petrous and squamous parts of the temporal bone. Similarly, care must be taken to protect the artery during surgical operations that involve the maxillary artery and the vidian nerve.

AIM

To evaluate the morphometry and clinical correlates of the middle meningeal artery in the black population of South Africa.

METHODS

The current study investigated the organization of the MMA in 100 adult dry human skulls (n = 50 males: n = 50 females) by tracing its grooves and measuring the length of the MMA, its frontal branch (FB), parietal branch (PB), the angle between FB and PB, and the angle of MMA from the foramen ovale (FO) bilaterally.

RESULTS

In comparison to females, males had significantly longer left PB (P = 0.003) and a considerably larger right angle of the MMA from the FO (P = 0.018). Furthermore, the PB was significantly longer on the left side than the right side in the entire sample (P = 0.002). Other parameters had no significant differences in sex and side.

CONCLUSIONS

The longer PB and the larger angle of the MMA in males could be attributed to why there is a high incidence of chronic subdural hematomas and MMA aneurysms in males. The current study is the first to propose a possible explanation for the aforementioned findings with regard to the organization of the MMA.

Penetration of Non-Adhesive Gel-like Embolic Materials During Dural Vessels Embolization According to Characteristics of Tantalum Powder

Tantalum powder is included in the composition of Non-Adhesive Gel-like Embolic Materials (NAGLEMs) for X-ray opacity. The duration of X-ray opacity during embolization is primarily associated with the particle size, which differs in the most used NAGLEMs-ONYX (Medtronic) and SQUID (Balt). NAGLEMs are widely used for the embolization of branches of the middle meningeal artery (MMA) in patients with chronic subdural hematomas (CSDHs). Considering the size (5-15 microns) of the target dural vessels, we assumed that not only the viscosity of NAGLEMs, but also the size and shape of tantalum granules may be important for the penetration of these gel-like embolic agents and determine their behavior. A notable discrepancy in size was observed. The medium-sized granules in the SQUID 18 sample (0.443 ± 0.086 microns, M ± SD) were found to be approximately ten times smaller than the tantalum granules in the ONYX 18 sample (5.2 ± 0.33 microns, M ± SD).Tantalum granules in SQUID 18 have a regular spherical shape; in ONYX 18 they have an irregular angular shape. When comparing the behavior of gel-like embolic agents of the same viscosity during MMA embolization in patients with CSDHs (an average age of 62.2 ± 14.3 years) in the group where SQUID 18 (n = 8) was used, the gel-like embolic agent in dural vessels demonstrated significantly greater penetration ability compared with the group where ONYX 18 (n = 8) was used. Accordingly, not only the viscosity of NAGLEMs, but also the size and shape of tantalum granules can have a significant effect on the penetration ability of gel compositions.

Embolic Materials' Comparison in Meningeal Artery Embolization for Chronic Subdural Hematomas: Multicenter Propensity Score-Matched Analysis of 1070 Cases

BACKGROUND AND OBJECTIVES

Multiple preferences exist for embolic materials selection in middle meningeal artery embolization (MMAE) for chronic subdural hematoma with limited comparative literature data. Herein, we compare different embolic materials.

METHODS

Consecutive patients undergoing MMAE for chronic subdural hematoma at 14 North-American centers (2018-2023) were classified into 3 groups: (a) particles, (b) Onyx, (c) n-butyl cyanoacrylate (n-BCA). The end points were unplanned rescue surgery, radiographic success (≥50% reduction in hematoma thickness at last imaging "minimum of 2 weeks"), and major complications. Initial unmatched analysis compared the 3 groups; subsequent propensity score matching (PSM) compared particles vs liquid embolics (groups b and c combined). Additional subgroup PSM analyses compared particles vs Onyx, particles vs n-BCA, and Onyx vs n-BCA. All matched analyses controlled for age, sex, concurrent surgery, previous surgery, hematoma thickness, midline shift, pretreatment antithrombotics, and baseline modified Rankin Scale.

RESULTS

Eight hundred and seventy-two patients (median age 73 years, 72.9% males) underwent 1070 MMAE procedures. Onyx was most used (41.4%), then particles (40.3%) and n-BCA (15.5%). Surgical rescue rates were comparable between particles, Onyx, and n-BCA (9.8% vs 7% vs 11.7%, respectively, P = .14). Similarly, radiographic success (78.8% vs 79.3% vs 77.4%; P = .91) and major complications (2.4% vs 2.3% vs 2.5%; P = .83) were comparable. The PSM comparing particles vs liquid generated 128 matched pairs; general anesthesia and bilateral procedures were significantly higher in particles (37.8% vs 21.3%; P = .004 and 39.8% vs 27.3%; P = .034, respectively). No differences in surgical rescue, radiographic improvement, or major complications were noted ( P > .05). Concurrently, PSM comparing particles vs Onyx, particles vs n-BCA, and Onyx vs n-BCA, resulted in 112, 42, and 40 matched pairs, respectively, without differences in surgical rescue, radiographic success, or major complications ( P > .05).

CONCLUSION

We found no differences in radiological improvement, surgical rescue, or major complications between embolic materials in MMAE. Current randomized trials are exclusively using liquid embolics, and these data suggest that future trials involving particles are likely to produce similar outcomes.

Medical management of chronic subdural hematoma with low-dose hydrocortisone: a case series

Chronic subdural hematomas (cSDH) are often managed with a burr-hole craniostomy and drainage, but surgery is associated with elevated mortality, morbidity, and recurrence. Despite reports of steroid use for such patients, its efficacy and feasibility are still debated. We present our patient series treated with low-dose hydrocortisone. We retrospectively reviewed data from patients treated with hydrocortisone between 2017 and 2023. Demographics, clinical and radiological data were collected. Of 27 patients identified, nine required a burr-hole craniotomy for an average volume of 120.23 cm3, average midline shift of 9 mm, and neurological deficits. Eighteen met the criteria for inclusion. The mean age was 78.5 years; 13 were male. None had severe symptoms requiring urgent intervention. Except for one with a Karnofsky Performance Scale score of 70, all could maintain normal activity before treatment. The mean baseline volume was 52.6 cm3. Midline shift, present in six, averaged 6.8 mm. Patients underwent treatment for an average of 5.15 months. Nine had complete resolution within 3 months, while nine required longer treatment, including one who needed 9 months for a re-bleed after a fall. Paired t-tests indicated significant reductions in hematoma volumes at the second week (p = 0.01), first month (p < 0.0001), and third month (p < 0.0001) of treatment. No complications occurred and the post-treatment Karnofsky scores ranged from 90 to 100. Treatment for cSDH should be tailored to the patient. Low-dose hydrocortisone is safe and effective in asymptomatic patients, those with mild to moderate symptoms, and those who are either unsuitable for or decline surgical intervention.

Quantifying extent of meningioma preoperative embolization through volumetric analysis: A retrospective case series

BACKGROUND

Endovascular embolization is an adjunct to meningioma resection. Isolating the effectiveness of embolization is difficult as MR imaging is typically performed before embolization and after resection, and volumetric assessment of embolization on 2D angiographic imaging is challenging. We investigated the correlation between 2D angiographic and 3D MR measurements of meningioma devascularization following embolization.

METHODS

We implemented a protocol for postembolization, preresection MRI. Angiographic devascularization was graded according to reduction of tumor blush from 1 (partial embolization) to 4 (complete embolization with no residual circulation supply). Volumetric extent of embolization was quantified as the percent of tumor contrast enhancement lost following embolization. Tumor embolization was analyzed according to tumor location and vascular supply.

RESULTS

Thirty consecutive patients met inclusionary criteria. Grade 1 devascularization was achieved in 7% of patients, grade 2 in 43%, grade 3 in 20%, and grade 4 in 30%. Average extent of embolization was 37 ± 6%. Extent of tumor embolization was low (<25%) in 40%, moderate (25%-75%) in 40%, and high (>75%) in 20% of patients. Convexity, parasagittal/falcine and sphenoid wing tumors were found to have distinct vascular supply patterns and extent of embolization. Angiographic devascularization grade was significantly correlated with volumetric extent of tumor embolization (p < 0.001, r = 0.758).

CONCLUSION

This is the first study to implement postembolization, preoperative MRI to assess extent of embolization prior to meningioma resection. The study demonstrates that volumetric assessment of contrast reduction following embolization provides a quantitative and spatially resolved framework for assessing extent of tumor embolization.

Transradial versus transfemoral access for middle meningeal artery embolization: Choice of the access route considering delirium in the elderly

Background

Treatment of chronic subdural hematoma (CSDH) with middle meningeal artery embolization (MMAE) is becoming well established. Transradial artery access (TRA) is considered less invasive than transfemoral artery access (TFA) and is increasingly indicated in the field of endovascular therapy. Therefore, this study focused on postoperative delirium and compared access routes.

Methods

This is a single-center and retrospective study. The strategy was to perform MMAE for CSDH with symptomatic recurrence at our hospital. Cases from July 2018 to September 2022, when MMAE was introduced in our hospital, were included in this study. Patients were divided into TRA and TFA groups and were compared descriptively for patient background, procedure duration, and incidence of postoperative delirium.

Results

Twenty-five patients underwent MMAE, of whom 12 (48%) were treated with TRA. The overall median age was 82 years, with no clear differences between the TRA and TFA groups in the presence or absence of preexisting dementia or antithrombotic therapy. Delirium requiring medication tended to be lower in the TRA group: 2/12 (16.7%) in the TRA group versus 6/13 (46.2%) in the TFA group, and the mean procedure time for patients undergoing bilateral MMAE was 151 min (interquartile range [IQR]: 140-173 min) in the TRA group versus 174 min (IQR: 137-205 min) in the TFA group.

Conclusion

TRA was associated with an overall shorter procedure time than TFA. MMAE through TRA tended to have a lower incidence of delirium. MMAE through TRA may be useful in recurrent CSDH with a high elderly population.

Initial experience using middle meningeal artery embolisation for patients with recurrent and high-recurrence-risk chronic subdural haematoma

Recurrence rates following surgical management of chronic subdural haematoma (CSDH) range from 5 to 33 %. There is growing evidence which suggests middle meningeal artery embolisation (MMAe) may reduce recurrence rates when used as surgical adjunct or standalone treatment. In this study we described our experience of this new procedure in the our UK institution. Patients with recurrent CSDH or CSDH at high risk of recurrence were selected for MMAe on a case-by-case basis following MDT discussion. A departmental database was used to identify patients treated. 26 CSDH were embolised in 20 patients; 9 CSDH were de-novo and 17 were recurrent. 10/26 CSDH were treated with MMAe only. No procedural mortality, access site or thrombo-embolic complications occurred. One patient experienced symptomatic collection growth 12 h following MMAe and required surgical drainage. 15 (75 %) of patients were living at home at follow-up (mean 14 months). On imaging follow-up 15/18 showed CSDH volume reduction or resolution, 1/18 remained stable requiring no further treatment, 2/18 patients suffered recurrent CSDH requiring treatment. In both recurrent cases incomplete embolisation was noted on procedural imaging (posterior division of MMA not embolised). Persistent posterior MMA division filling was significantly associated with collection recurrence (p = 0.002). Our results suggest MMAe as a stand-alone or adjuvant therapy can be performed safely in a UK neuroscience setting and is associated with high rates of symptomatic CSDH size reduction or resolution in problematic CSDH that have either recurred or are prone to recurrence.

Middle Meningeal Artery Embolization in Acute Leukemia Patients Presenting With Subdural Hematoma

Intracerebral hemorrhage is a potentially fatal complication in patients with acute leukemia and contributing factors include thrombocytopenia and coagulopathy. Patients with acute leukemia may develop subdural hematoma (SDH) spontaneously or secondary to trauma. In patients with acute leukemia and SDH, the surgical evacuation of the hematoma causes significant morbidity and mortality. New approaches and strategies to reduce the need for surgical evacuation are needed to improve outcomes in patients with acute leukemia and intracerebral hemorrhage. We report two cases of acute SDH in patients with acute leukemia successfully treated with middle meningeal artery embolization, a minimally invasive interventional radiology technique, obviating the need for a surgical intervention. The first patient with acute promyelocytic leukemia (APL) presented with coagulopathy and developed an acute SDH after a fall. The second patient with acute myeloid leukemia presented with gum bleeding and also sustained an acute SDH after a fall. Both patients underwent middle meningeal artery embolization for treating their SDHs while actively receiving induction chemotherapy for acute leukemia. Both patients had resolution of their acute SDH and are in remission from their acute leukemia. Middle meningeal artery embolization is a very effective, and within the context of this setting, a novel, minimally invasive technique for management of SDH in acute leukemia patients, which can prevent the need for surgical interventions with its associated comorbidities and high risk of fatal outcomes in patients with acute leukemia and acute SDH.

Middle meningeal artery embolization for chronic subdural hematoma: A single-center experience and predictive modeling of outcomes

BACKGROUND

Remarkable interest is rising around middle meningeal artery embolization (MMAE) as an emerging alternative therapy for chronic subdural hematoma (cSDH). The study aims to highlight a large center experience and the variables associated with treatment failure and build experimental machine learning (ML) models for outcome prediction.

MATERIAL AND METHODS

A 2-year experience in MMAE for managing patients with chronic subdural hematoma was analyzed. Descriptive statistical analysis was conducted using imaging and clinical features of the patients and cSDH, which were subsequently used to build predictive models for the procedure outcome. The modeling evaluation metrics were the area under the ROC curve and F1-score.

RESULTS

A total of 100 cSDH of 76 patients who underwent MMAE were included with an average follow-up of 6 months. The intervention had a per procedure success rate of 92%. Thrombocytopenia had a highly significant association with treatment failure. Two patients suffered a complication related to the procedure. The best performing machine learning models in predicting MMAE failure achieved an ROC-AUC of 70%, and an F1-score of 67%, including all patients with or without surgical intervention prior to embolization, and an ROC-AUC of 82% and an F1-score of 69% when only patients who underwent upfront MMAE were included.

CONCLUSION

MMAE is a safe and minimally invasive procedure with great potential in transforming the management of cSDH and reducing the risk of surgical complications in selected patients. An ML approach with larger sample size might help better predict outcomes and highlight important predictors following MMAE in patients with cSDH.

Middle meningeal artery embolization for the treatment of unilateral large chronic subdural hematoma patients with significant midline shift: A single-center experience

BACKGROUND

The amount of midline shift (MLS) considered safe for middle meningeal artery embolization (MMAE) in patients with chronic subdural hematoma (CSDH) has not been established. Whether MMAE could be used as upfront treatment for unilateral large CSDH patients with significant MLS (>1 cm) has not been reported.

OBJECTIVE

To investigate the efficacy and safety of MMAE in unilateral large CSDH patients with MLS > 1 cm.

METHODS

Eleven carefully selected CSDH patients with mild or moderate symptoms and significant MLS > 1 cm from 1 May 2021 to 31 August 2022 were included in the study. All patients were treated with MMAE using polyvinyl alcohol (PVA) particles. Outcomes were assessed clinically and with interval imaging studies at follow-up.

RESULTS

All 19 MMAs (unilateral embolization in three patients and bilateral embolization in eight patients) were successfully embolized. All 11 patients were followed for subsequent months, and there was no recurrence and enlargement of CSDH. Procedural adverse events, mortality, or complications were not observed. The average time to achieve a 50% reduction in MLS was approximately four weeks, while it took approximately eight weeks to achieve a 50% reduction in maximal volume. All 11 patients showed improvement in their neurological symptoms at three days post-operation, including four hemiplegic patients.

CONCLUSIONS

MMAE may demonstrate safety in carefully selected CSDH patients with significant midline shift (MLS > 1 cm), particularly in those who are not suitable for surgery, thus providing a potential alternative approach.

Safety and efficacy comparison of embolic agents for middle meningeal artery embolization for chronic subdural hematoma

OBJECTIVE

To perform a systematic review and meta-analysis evaluating the efficacy of middle meningeal artery embolization in terms of both clinical and radiographic outcomes, when performed with different embolic agents.

METHODS

A systematic literature review and meta-analysis was performed to evaluate the impact of embolic agents on outcomes for middle meningeal artery (MMA) embolization. The use of polyvinyl alcohol (PVA) with or without (±) coils, N-butyl cyanoacrylate (n-BCA) ± coils, and Onyx alone were separately evaluated. Primary outcome measures were recurrence, the need for surgical rescue and in-hospital periprocedural complications.

RESULTS

Thirty-one studies were identified with a total of 1,134 patients, with 786 receiving PVA, 167 receiving n-BCA, and 181 patients receiving Onyx. There was no difference in the recurrence rate (5.5% for PVA, 4.5% for n-BCA, and 6.5% for Onyx, with P=0.71) or need for surgical rescue (5.0% for PVA, 4.0% for n-BCA, and 6.9% for Onyx, with P=0.89) based on the embolic agent. Procedural complications also did not differ between embolic agents (1.8% for PVA, 3.6% for n-BCA, and 1.6% for Onyx, with P=0.48).

CONCLUSIONS

Rates of recurrence, need for surgical rescue, and periprocedural complication following MMA embolization are not impacted by the type of embolic agent utilized. Ongoing clinical trials may be used to further investigate these findings.

General Versus Nongeneral Anesthesia for Middle Meningeal Artery Embolization for Chronic Subdural Hematomas: Multicenter Propensity Score Matched Study

BACKGROUND AND OBJECTIVES

The choice of anesthesia type (general anesthesia [GA] vs nongeneral anesthesia [non-GA]) in middle meningeal artery embolization (MMAE) procedures for chronic subdural hematomas (cSDH) differs between institutions and left to care team discretion given lack of standard guidelines. We compare the outcomes of GA vs non-GA in MMAE.

METHODS

Consecutive patients receiving MMAE for cSDH at 14 North American centers (2018-2023) were included. Clinical, cSDH characteristics, and technical/clinical outcomes were compared between the GA/non-GA groups. Using propensity score matching (PSM), patients were matched controlling for age, baseline modified Rankin Scale, concurrent/prior surgery, hematoma thickness/midline shift, and baseline antiplatelet/anticoagulation. The primary end points included surgical rescue and radiographic success rates (≥50% reduction in maximum hematoma thickness with minimum 2 weeks of imaging). Secondary end points included technical feasibility, procedural complications, and functional outcomes.

RESULTS

Seven hundred seventy-eight patients (median age 73 years, 73.2% male patients) underwent 956 MMAE procedures, 667 (70.4%) were non-GA and 280 were GA (29.6%). After running 1:3 PSM algorithm, this resulted in 153 and 296 in the GA and non-GA groups, respectively. There were no baseline/procedural differences between the groups except radial access more significantly used in the non-GA group (P = .001). There was no difference between the groups in procedural technical feasibility, complications rate, length of stay, surgical rescue rates, or favorable functional outcome at the last follow-up. Subsequent 1:1 sensitivity PSM retained the same results. Bilateral MMAE procedures were more performed under non-GA group (75.8% vs 67.2%; P = .01); no differences were noted in clinical/radiographic outcomes between bilateral vs unilateral MMAE, except for longer procedure duration in the bilateral group (median 73 minutes [IQR 48.3-100] vs 54 minutes [39-75]; P < .0001). Another PSM analysis comparing GA vs non-GA in patients undergoing stand-alone MMAE retained similar associations.

CONCLUSION

We found no significant differences in radiological improvement/clinical outcomes between GA and non-GA for MMAE.

In vitro comparison of middle meningeal artery embolization with Squid liquid embolic agent and Contour polyvinyl alcohol particles

BACKGROUND

Liquid embolic agents and polyvinyl alcohol (PVA) particles have been used for the embolization of the middle meningeal artery (MMA) for the treatment of chronic subdural hematomas. However, the vascular penetration and distribution of these embolic agents have not yet been compared. The current study compares distribution of a liquid embolic agent (Squid) to PVA particles (Contour) in an in vitro model of the MMA.

METHODS

MMA models were embolized with Contour PVA particles 45-150 µm, Contour PVA particles 150-250 µm, and Squid-18 liquid embolic agent (n=5 each). The models were scanned and every vascular segment with embolic agent was manually marked on the images. Embolized vascular length as a percentage of control, average embolized vascular diameter, and embolization time were compared between the groups.

RESULTS

The 150-250 µm Contour particles primarily accumulated close to the microcatheter tip, yielding proximal branch occlusions. The 45-150 µm Contour particles achieved a more distal distribution, but in a patchy segmental pattern. However, the models embolized with Squid-18 had a consistently distal, near-complete and homogenous distribution. Embolized vascular length was significantly higher (76±13% vs 5±3%, P=0.0007) and average embolized vessel diameter was significantly smaller (405±25 µm vs 775±225 µm, P=0.0006) with Squid than with Contour. Embolization time with Squid was also lower (2.8±2.4 min vs 6.4±2.7 min, P=0.09).

CONCLUSIONS

Squid-18 liquid results in a considerably more consistent, distal and homogeneous pattern of embolysate distribution than Contour PVA particles in an anatomical model of the MMA tree.

Anomalous branching of the middle meningeal artery from the basilar artery: a systematic review

Background

Anomalous origin of the middle meningeal artery (MMA) from the basilar artery is a rare congenital neurological variant that has been detected in both children and adults with diagnoses ranging from intracranial haemorrhage to ependymoma. This review aims to investigate the anatomical course of an anomalous basilar-middle meningeal artery and its clinical presentation.

Methods

A systematic search was performed in PubMed using the keywords (middle meningeal artery) and (basilar artery). Ninety-four papers were identified, of which seven were included. One paper was further identified through cross-referencing.

Results

The average age of presentation was 43 years with a male predominance (7/9). In most cases, the MMA arose between the superior cerebellar artery and the anterior inferior cerebellar artery (8/9) (versus 1 case between the anterior inferior cerebellar artery and the posterior inferior cerebellar artery). The anomaly mostly presented on the left side (6/11), but was bilateral in one case. Most of the cases showed a pontine artery branching from the basilar artery arising 5 mm to 10 mm proximal to the superior cerebellar artery, which would then assume the trajectory of the MMA. In three cases, the vessel increased in calibre near the trigeminal ganglion. Foramen spinosum absence in the anomalous side was noted in 3/6 of the patients.

Conclusion

To avoid unexpected complications during neurosurgical and neuroradiointerventional procedures, it is essential to have a clear understanding of the anomalous routes of the MMA. This is especially important when it proves to be the only available route for embolization.

Immediate procedural safety of adjunctive proximal coil occlusion in middle meningeal artery embolization for chronic subdural hematomas: Experience in 137 cases

BACKGROUND

Endovascular embolization of the middle meningeal artery (MMA) has emerged as an adjunctive and stand-alone modality for the management of chronic subdural hematomas (cSDH). We report our experience utilizing proximal MMA coil embolization to augment cSDH devascularization in MMA embolization.

METHODS

MMA embolization cases with adjunctive proximal MMA coiling were retrospectively identified from a prospectively maintained IRB-approved database of the senior authors.

RESULTS

Of the 137 cases, all patients (n = 89, 100%) were symptomatic and underwent an MMA embolization procedure for cSDH. 50 of the patients underwent bilateral embolizations, with 53% (n = 72) for left-sided and 47% (n = 65) for right-sided cSDH. The anterior MMA branch was embolized in 19 (14%), posterior in 16 (12%), and both in 102 (74.5%) cases. Penetration of the liquid embolic to the contralateral MMA or into the falx was present in 38 (28%) and 31 (23%) cases, respectively, and 46 (34%) cases had ophthalmic or petrous collateral (n = 41, 30%) branches. MMA branches coiled include the primary trunk (25.5%, n = 35), primary and anterior or posterior MMA trunks (20%, n = 28), or primary with the anterior and posterior trunks (54%, n = 74). A mild ipsilateral facial nerve palsy was reported, which remained stable at discharge and follow-up. Absence of anterograde flow in the MMA occurred in 137 (100%) cases, and no cases required periprocedural rescue surgery for cSDH evacuation. The average follow-up length was 170 ± 17.9 days, cSDH was reduced by 4.24 ± 0.5(mm) and the midline shift by 1.46 ± 0.27(mm). Complete resolution was achieved in 63 (46.0%) cases.

CONCLUSION

Proximal MMA coil embolization is a safe technique for providing additional embolization/occlusion of the MMA in cSDH embolization procedures. Further studies are needed to evaluate the potential added efficacy of this technique.

Tonetti D, Bounajem MT, Thomas A, Ogilvy CS, Moore JM, Riina HA, Tanweer O, Levy EI, Spiotta AM, Gross BA, Jankowitz BT, Cawley CM, Khalessi AA, Pandey AS, Ringer AJ, Hanel R, Ortiz RA, Langer D, Levitt MR, Binning M, Taussky P, Kan P, Grandhi R. Radiographic and clinical outcomes with particle or liquid embolic agents for middle meningeal artery embolization of nonacute subdural hematomas

BACKGROUND

Middle meningeal artery (MMA) embolization is an apparently efficacious minimally invasive treatment for nonacute subdural hematomas (NASHs), but how different embolisates affect outcomes remains unclear. Our objective was to compare radiographic and clinical outcomes after particle or liquid MMA embolization.

METHODS

Patients who had MMA embolization for NASH were retrospectively identified from a multi-institution database. The primary radiographic and clinical outcomes-50% NASH thickness reduction and need for surgical retreatment within 90 days, respectively-were compared for liquid and particle embolizations in patients treated 1) without surgical intervention (upfront), 2) after recurrence, or 3) with concomitant surgery (prophylactic).

RESULTS

The upfront, recurrent, and prophylactic subgroups included 133, 59, and 16 patients, respectively. The primary radiographic outcome was observed in 61.8%, 61%, and 72.7% of particle-embolized patients and 61.3%, 55.6%, and 20% of liquid-embolized patients, respectively (p = 0.457, 0.819, 0.755). Hazard ratios comparing time to reach radiographic outcome in the particle and liquid groups or upfront, recurrent, andprophylactic timing were 1.31 (95% CI 0.78-2.18; p = 0.310), 1.09 (95% CI 0.52-2.27; p = 0.822), and 1.5 (95% CI 0.14-16.54; p = 0.74), respectively. The primary clinical outcome occurred in 8.0%, 2.4%, and 0% of patients who underwent particle embolization in the upfront, recurrent, and prophylactic groups, respectively, compared with 0%, 5.6%, and 0% who underwent liquid embolization (p = 0.197, 0.521, 1.00).

CONCLUSIONS

MMA embolization with particle and liquid embolisates appears to be equally effective in treatment of NASHs as determined by the percentage who reach, and the time to reach, 50% NASH thickness reduction and the incidence of surgical reintervention within 90 days.

Subdural haematoma in the elderly: management and outcomes of a UK Major Trauma Centre

BACKGROUND

An estimated 40% of all traumatic brain injury (TBI) occurs in ≥70-year-olds with a high prevalence of traumatic subdural haematoma (tSDH). It is anticipated that an expanding elderly population will lead to a proportional increase in the incidence of patients with tSDH presenting to UK trauma centres, but the long-term clinical outcomes and factors influencing functional outcomes in this patient group remain poorly understood.

AIM

To examine the management and clinical outcomes for elderly (≥70 years) patients diagnosed with tSDH.

METHODS

Patient data for this single-centre, retrospective cohort study were analysed from a Major Trauma Centre (MTC) electronic patient records between January 2013 and December 2019.

RESULTS

Two hundred and eighty patients were included, 43% aged 70-79, 42% aged 80-89 and 15% >90. In total, 37% underwent a surgical intervention. The 6-month survival in the severe, moderate, and mild TBI groups was 14%, 43%, and 67%, respectively. The 6-month survival in the surgical group was 58%, vs. 60% in the conservatively managed group. Surgical intervention did not significantly impact Extended Glasgow Coma Score (GOS-E) at 6 months, regardless of injury severity. Advanced age (p = 0.04), mixed intracranial injuries (p < 0.0001), craniotomies (p = 0.03), and poor premorbid performance status (p = 0.02) were associated with worse survival and functional outcomes.

CONCLUSIONS

Our study demonstrated that increasing age, increasing severity of TBI and poorer premorbid performance status were associated with significantly poorer 6-month survival and functional outcomes in elderly patients with tSDH. Burr hole evacuation was associated with better functional outcomes compared to craniotomy, but overall, there was no significant difference in the outcomes of the surgical and non-surgical groups. We identified strong risk factors for death and poor functional outcomes at 6-months which are important to consider when counselling patients and families about the long-term prognosis of elderly patients with tSDH and can help guide clinical decision-making.

Safety of middle meningeal artery embolization for treatment of subdural hematoma: A nationwide propensity score matched analysis

OBJECTIVE

Middle meningeal artery embolization (MMAe) has burgeoned as a treatment for chronic subdural hematoma (cSDH). This study evaluates the safety and short-term outcomes of MMAe patients relative to traditional treatment approaches.

METHODS

In this retrospective large database study, adult patients in the National Inpatient Sample from 2012-2019 with a diagnosis of cSDH were identified. Cost of admission, length of stay (LOS), discharge disposition, and complications were analyzed. Propensity score matching (PSM) was utilized.

RESULTS

A total of 123,350 patients with cSDH were identified: 63,450 without intervention, 59,435 surgery only, 295 MMAe only, and 170 surgery plus MMAe. On PSM analysis, MMAe did not increase the risk of inpatient complications or prolong the length of stay compared to conservative management (p>0.05); MMAe had higher cost ($31,170 vs. $10,768, p<0.001) than conservative management, and a lower rate of nonroutine discharge (53.8% vs. 64.3%, p=0.024). Compared to surgery, MMAe had shorter LOS (5 vs. 7 days, p<0.001), and lower rates of neurological complications (2.7% vs. 7.1%, p=0.029) and nonroutine discharge (53.8% vs. 71.7%, p<0.001). There was no significant difference in cost (p>0.05).

CONCLUSIONS

MMAe had similar LOS and decreased odds of adverse discharge with a modest cost increase compared to conservative management. There was no difference in inpatient complications. Compared to surgery, MMAe treatment was associated with decreased LOS and rates of neurological complications and nonroutine discharge. This nationwide analysis supports the safety of MMAe to treat cSDH.

Middle meningeal artery embolization for chronic subdural hematoma: a systematic review

Background

Chronic subdural hematoma (cSDH) is one of the most common diseases in neurosurgery. Middle meningeal artery embolization (MMAE) is reportedly an option to prevent recurrence or avoid surgery in patients with cSDH. This study was performed to review the evidence on MMAE for cSDH and evaluate its safety, efficacy, indications, and feasibility.

Methods

We systematically reviewed the literature according to the PRISMA guidelines using an electronic database. The search yielded 43 articles involving 2,783 patients who underwent MMAE.

Results

The hematoma resolution, recurrence, and retreatment rates in the MMAE-alone treatment group (n = 815) were 86.7%, 6.3%, and 9.6%, respectively, whereas those in the prophylactic MMAE with combined surgery group (n = 370) were 95.6%, 4.4%, and 3.4%, respectively. The overall MMAE-related complication rate was 2.3%.

Conclusion

This study shows that MMAE alone is, although not immediate, as effective as evacuation surgery alone in reducing hematoma. The study also shows that combined treatment has a lower recurrence rate than evacuation surgery alone. Because MMAE is a safe procedure, it should be considered for patients with cSDH, especially those with a high risk of recurrence.

Volumetric resolution of chronic subdural hematomas treated with surgical evacuation versus middle meningeal artery embolization during immediate, early, and late follow up: propensity-score matched cohorts

BACKGROUND

Literature on volumetric resolution and recurrence over time between surgical evacuation alone (SEA) and standalone middle meningeal artery embolization (MMAE) in comparable chronic subdural hematoma (cSDH) patients is limited.

METHODS

A retrospective database analysis of cSDH patients managed with either SEA or MMAE was conducted. Propensity-score matching was performed for axial and coronal lengths, maximum diameter, and midline shift. Volumetric measurements at multiple time intervals and recurrence were compared between the groups.

RESULTS

48 matched hematoma pairs in patients with similar demographics, comorbidities, medications, and symptoms were obtained. Median volume was significantly lower at 24 hours in the SEA group (12.6 mL vs 52.7 mL, p<0.001) but not at remaining intervals. Median volume reduction was significantly greater in the SEA group at 24 hours (39.1 mL vs 8.8 mL in the MMAE group, p<0.001) and at 3-12 weeks (50.8 mL vs 23.7 mL, p<0.001), but not at remaining intervals. The SEA group had a significantly greater median hematoma resolution rate at 24 hours (39.1 mL/day vs 8.8 mL/day, p<0.001) and 3-12 weeks (1 mL/day vs 0.4 mL/day, p<0.001), but not at remaining intervals. Near-complete resolution at 3-12 weeks and 12-60 weeks was not significantly different between groups. Overall, the recurrence rate was significantly higher in the SEA group (22.9% vs 4.2%, p=0.01).

CONCLUSIONS

In comparable cSDH patients, SEA resulted in better volumetric outcomes in immediate postoperative and early follow-up periods, as expected. However, this difference was not significant at more distant follow-up intervals. Furthermore, surgical patients experienced a significantly higher rate of recurrence.

A systematic review of middle meningeal artery embolization for minimally symptomatic chronic subdural haematomas that do not require immediate evacuation

Introduction

Embolization of the Middle Meningeal Artery (EMMA) is an emerging treatment option for patients with Chronic Subdural Haematoma (CSDH).

Questions

(1) Can EMMA change the natural history of untreated minimally symptomatic CSDH which do not require immediate evacuation? (2) What is the role of EMMA in the prevention of recurrence following surgical treatment? (3) Can the procedure be performed under local anaesthetic?

Material and methods

Systematic literature review. No randomised clinical trials available on EMMA for meta-analysis.

Results

Six unique large cohorts with more than 50 embolisations were identified (evidence: 3b-4). EMMA can control the progression of surgically naïve CSDH in 91.1-100% of the patients, in which haematoma expansion is halted, or the lesion decreases and resolves. Treatment failure requiring surgery occurs in 0-4.1% of the patients having EMMA as the primary and only treatment. Treatment failure requiring surgery goes up slightly to 6.8% if post-surgical patients are included. When EMMA is used as postsurgical adjunctive the risk of recurrence is 1.4-8.9% compared to 10-20% in surgical series. EMMA has minimal morbidity and it is feasible under local anaesthesia or slight sedation in the majority of cases.

Conclusion

There is cumulative low-quality evidence in the literature that EMMA may be able to modify the natural course of the disease. It appears effective in controlling progression of CSDHs in patients having it as a primary standing alone treatment and it reduces the risk of recurrence and the need for surgical intervention in refractory postsurgical cases or as a postsurgical adjunctive treatment with minimal morbidity (recommendation: C).

Middle Meningeal Artery Embolization with Liquid Embolic Agents for Chronic Subdural Hematoma: A Systematic Review and Meta-analysis

PURPOSE

To assess the efficacy and safety of middle meningeal artery (MMA) embolization with liquid embolic agents and the outcomes of patients following this procedure.

MATERIALS AND METHODS

A review of the literature was conducted to identify studies investigating the efficacy and safety of MMA embolization with liquid embolic agents in patients with chronic subdural hematoma (cSDH) in PubMed, Scopus, Embase, and Web of Science. The keywords "liquid embolic agent," "middle meningeal artery," "cSDH," and "embolization" as well as their synonyms were used to build up the search strategy. The R statistical software and random-effects model were used for analysis. Heterogeneity was reported as I2, and publication bias was calculated using the Egger test.

RESULTS

Of 628 articles retrieved, 14 studies were eligible to be included in this study. Data of 276 patients were analyzed. n-Butyl cyanoacrylate and ethylene vinyl alcohol copolymer were the most commonly used embolic agents. This study revealed a pooled mortality rate of 0% (95% confidence interval [CI], 0.00%-100%), recurrence and failure rate of 3% (95% CI, 1%-10%), reoperation/reintervention rate of 4% (95% CI, 2%-12%), rate of size decrease of 94% (95% CI, 79%-98%), technical success rate of 100% (95% CI, 76%-100%), and adverse event rate of 1% (95% CI, 0.00%-4%).

CONCLUSIONS

With low mortality, recurrence, reoperation, and adverse event rates and a remarkable decrease in the size of hematomas, MMA embolization with liquid embolic agents may be considered a safe and effective treatment option in patients in whom surgical intervention has previously failed and as an alternative to conventional treatments.

Extensive Roles and Technical Advances of Middle Meningeal Artery Embolization for Chronic Subdural Hematoma

Chronic subdural hematoma (CSDH) is a common pathology that typically affects the elderly in Japan, an aging society. Burr-hole irrigation is the standard treatment, but middle meningeal artery (MMA) embolization is a minimally invasive alternative. MMA embolization for CSDH has frequently been reported in recent years, and many technical innovations to improve clinical outcomes have been described. Embolic materials reaching more distally are found to avoid recurrences after MMA embolization. As a result, various studies have described the superiority of embolizing the anterior and posterior branches of the MMA, the advantages of embolic materials reaching beyond the midline, and a high degree of distal penetration using a "sugar rush technique" in which 5% soluble glucose is injected through an intermediate catheter during MMA embolization. Radiographically, reports have described the importance of a "bright falx" sign obtained by infiltrating embolic material beyond the midline and post-embolization enhancement of the dura, capsular membrane, septations, and subdural hematoma fluid as indicators of the spread of embolic materials. This review provides an overview of the current status and future challenges in MMA embolization for CSDH, focusing on technical aspects to improve clinical outcomes.

Awake transradial middle meningeal artery embolization and twist drill craniostomy for chronic subdural hematomas in the elderly: case series and technical note

BACKGROUND

Due to prohibitive perioperative risk factors, optimal treatment for chronic subdural hematomas (cSDH) in the elderly remains unclear. Minimally invasive techniques are a viable option and include bedside subdural evacuation port system (SEPS), as well as prevention of recurrence with middle meningeal artery (MMA) embolization. We present a case series of elderly patients undergoing combined transradial MMA embolization and bed-side craniostomy as primary treatment for cSDH.

METHODS

Patients 70 years and older from 2019 to 2020 that underwent single setting, awake transradial MMA embolization with concurrent SEPS placement under local anesthesia were included. Those with prior treatments, interventions performed under general anesthesia, or with less than 60-day follow-up were excluded. Descriptive analyses of baseline characteristics, radiologic parameters, comorbidities, and outcome measures were completed.

RESULTS

Twenty elderly patients (mean age of 81.0 years) with multiple comorbidities underwent 28 MMA embolization+SEPS procedures as primary treatment for cSDH. Mean cSDH thickness was 1.8cm±0.6 cm with 7.3±3.9 mm midline shift. All patients tolerated the procedure well. 1/20 (5.0%) patients died within 30 days of the procedure. A majority of patients were discharged to home (12/20; 60.0%). There was an average of 3.6-month follow-up and one patient (5.0%) developed recurrence in the follow-up period requiring further intervention.

CONCLUSIONS

In select elderly patients with high perioperative risk factors, primary treatment of cSDH using awake transradial MMA embolization+SEPS placement is a minimally invasive, feasible, and safe option. Further comparative studies are warranted to evaluate efficacy of the treatment.

Middle meningeal artery embolization for treatment of chronic subdural hematomas: does selection of embolized branches affect outcomes?

OBJECTIVE

Middle meningeal artery (MMA) embolization (MMAE) is a new therapeutic modality for chronic subdural hematoma (cSDH). There is limited evidence comparing various MMAE procedural techniques, resulting in significant variations in technique and procedural planning. The objective of this study was to compare outcomes of MMAE by the number and location of MMA branches that were embolized.

METHODS

A single-center retrospective study of patients with cSDH treated by MMAE was conducted. Clinical outcomes, need for re-intervention, and changes in hematoma size were compared between different MMAE techniques.

RESULTS

Ninety-four cSDHs in 78 patients were included. Embolization of the proximal trunk only, distal branches only, or proximal trunk plus distal branches resulted in similar rates of need for rescue surgery (7.4%, 13.0%, and 6.8%, respectively; p = 0.66) and rates of reducing the volume of the hematoma by at least 50% (74.1%, 80.0%, and 77.5%, respectively; p = 0.88). Embolization of only one branch had similar outcomes to embolization of more than one branch, as rescue surgery rates were 9.3% and 7.8% (p = 0.80), and rates ≥ 50% volume reduction were 75.6% and 78.3% (p = 0.76), respectively. Selective embolization of the dominant MMA branch was not associated with significantly different outcomes.

CONCLUSIONS

Outcomes of distal, proximal, or combined proximal and distal MMAE in cSDH are not significantly different. Embolization of more than one branch is not associated with improved treatment efficacy. Arguably, targeting any location in the MMA provides sufficient flow restriction to enable spontaneous hematoma resolution. Accordingly, a technical planning algorithm for cSDH MMAE is suggested.

Embolization of the middle meningeal artery vs. second surgery-treatment response and volume course of recurrent chronic subdural hematomas

BACKGROUND

Despite multiple studies on the embolization of the middle meningeal artery, there is limited data on the treatment response of recurrent chronic subdural hematomas (CSDH) to embolization and on the volume change.

METHODS

We retrospectively compared the treatment response and volume change of recurrent CSDHs in a conventional group (second surgery) with an embolization group (embolization as stand-alone treatment) during the time-period from August 2019 until June 2022. Different clinical and radiological factors were assessed. Treatment failure was defined as necessity of treatment for second recurrence. Hematoma volumes were determined in the initial CT scan before first surgery, after the first surgery, before retreatment as well as in an early (1 day-2 weeks) and in a late follow-up CT scan (2-8 weeks).

RESULTS

Fifty recurrent hematomas after initial surgery were treated either by second surgery (n = 27) or by embolization (n = 23). 8/27 (26,6%) surgically treated and 3/23 (13%) of the hematomas treated by embolization needed to be treated again. This leads to an efficacy in recurrent hematomas of 73,4% in surgically treated and of 87% in embolized hematomas (p = 0.189). In the conventional group, mean volume decreased significantly already in the first follow-up CT scan from 101.7 ml (SD 53.7) to 60.7 ml (SD 40.3) (p = 0.001) and dropped further in the later follow-up scan to 46.6 ml (SD 37.1) (p = 0.001). In the embolization group, the mean volume did decrease insignificantly from 75.1 ml (SD 27.3) to 68 ml (SD 31.4) in the first scan (p = 0.062). However, in the late scan significant volume reduction to 30.8 ml (SD 17.1) could be observed (p = 0.002).

CONCLUSIONS

Embolization of the middle meningeal artery is an effective treatment option for recurrent CSDH. Patients with mild symptoms who can tolerate slow volume reduction are suitable for embolization, whereas patients with severe symptoms should be reserved for surgery.

Short-term follow-up pilot study of sole middle meningeal artery embolization for chronic subdural hematoma: influence of internal architecture on the radiological outcomes

PURPOSE

To identify prognostic factors with emphasis on chronic subdural hematoma (CSDH) architecture that determines short-term outcome of middle meningeal artery embolization (MMAE).

METHODS

Consecutive CSDH patients treated by MMAE (November 2019 and March 2022) were retrospectively analyzed. Four architectures were analyzed: homogeneous, laminar, separated, and trabecular types. Predictor variables from baseline CT were correlated with radiological endpoint (≥ 50% of hematoma volume reduction), time to reach the endpoint, and rate of volume reduction.

RESULTS

Study included 50 patients with 56 CSDHs (median age [first quartile, Q1; third quartile, Q3] 70.5 [60, 78.3] years; 36 were men). Separated type reached the endpoint at a lower rate on both bivariate (p = 0.02) and multivariate Cox model (0.034). Kaplan-Meier curves demonstrated that the median [Q1, Q3] time for 50% of the hematomas to reach the endpoint was 5 [4, 8], 4 [3, 5], 15 [15, 15], and 11 [4, 19] weeks for homogeneous, laminar, separated, and trabecular types, respectively. Linear mixed-effect model demonstrated a significant variation in the slope of hematoma volume reduction that was - 4.16 (95% confidence interval [CI] - 5.4, - 2.9), - 6.7 (95% CI - 8.35, - 5.1), - 2.03 (95% CI - 4.14, 0.08), and - 5.06 (95% CI - 6.8, - 3.32) ml per week for homogeneous, laminar, separated, and trabecular subtypes, respectively.

CONCLUSION

Separated CSDH is a poor prognostic type in achieving radiological endpoint and a slower rate of volume reduction. While, homogeneous and laminar types reached the endpoint faster than separated and trabecular types on short-term follow-up.

Outcomes of Particle versus Liquid Embolic Materials Used in Middle Meningeal Artery Embolization for the Treatment of Chronic Subdural Hematoma

BACKGROUND

Early evidence suggests that middle meningeal artery (MMA) embolization is an efficacious minimally invasive neuroendovascular technique for the management of chronic subdural hematoma (cSDH). Particle and liquid embolic materials are commonly used to embolize the MMA; however, studies comparing the safety and outcomes between these 2 materials are limited.

METHODS

Patients ≥18 years old who had MMA embolization for cSDH between July 15, 2020 and May 1, 2022 were retrospectively identified from a single-center database. The primary safety, radiation dosage, fluoroscopy time, and radiographic and clinical outcomes were compared between particle and liquid embolization.

RESULTS

In a cohort of 116, 48 (41.38%) were treated with liquid embolic material and 68 (58.62%) were treated with particle. The median age of the cohort was 73 years in the particle group and 73.5 years in the liquid embolic group. There was no significant difference in radiation dose or duration among both groups. There was no reported mortality associated with the procedure. One patient experienced nondisabling ischemic stroke in the particle group. Based on imaging follow-up, 3 patients in the particle group and 1 in the liquid embolic group had asymptomatic recurrence. One patient in each group had symptomatic recurrence requiring hematoma evacuation. The index median size of hematoma was 12 mm in the particle group and 11 mm in the liquid embolic group. At approximately 1 month follow-up, the median size of hematoma reduced to 6 mm in both groups.

CONCLUSIONS

Our series shows that liquid embolic and particle embolization are equally safe and effective among patients undergoing MMA embolization for management of cSDH.

Usage of Tranexamic Acid for Treatment of Subdural Hematomas

The collection of blood in the subdural layer within the cranium is classified as a subdural hematoma. Prevalence of subdural hematomas is most common among older populations with the current standard of treatment being invasive surgical evacuation for patients presenting with acute subdural hematomas with a midline shift greater than 5 mm on computed tomography (CT).Tranexamic acid (TXA) has been identified as an alternative, non-invasive option to treat patients presenting with subdural hematoma who are not suitable for surgical intervention. The presenting case involves a 90-year-old female who arrived with a code stroke with the chief complaint of right lower extremity weakness. A stroke series CT panel revealed a left frontal multiloculated subdural hematoma, measuring 130 mL with mass effect and a midline shift of 7 mm. The patient was recommended a craniotomy for hematoma evacuation or access to hospice for comfort care. A second opinion resulted in the administration of TXA. After the full completion of a TXA course, the patient achieved baseline mobility. The final measurements revealed a final hematoma volume of 10 mL and a midline shift of less than 2 mm. Current literature, as well as the case described, has begun demonstrating the efficacy of the usage of TXA in the reabsorption of subdural hematomas and should encourage further exploration into society guidelines for the usage of TXA as a non-invasive alternative to treat subdural hematomas.

Cost Comparison for Open Surgery versus Middle Meningeal Artery Embolization in Patients with Chronic Subdural Hematomas: A Propensity Score-Matched Analysis

BACKGROUND

Chronic subdural hematoma (cSDH) can be treated with conventional surgery or middle meningeal artery embolization (MMAE). The cost profiles of open surgery versus MMAE have never been studied. Therefore, we sought to compare the costs of surgical and MMAE treatment of cSDH.

METHODS

Patients treated with open surgery (2006-2019) and MMAE (2018-2020) were identified from the institutional database. Propensity score matching analysis was used to assemble a balanced group of subjects. Detailed hospitalization costs in each group were collected and compared.

RESULTS

A total of 341 conventionally treated and 52 MMAE cases were identified. After propensity score matching, 33 patients were included in each group, for a total of 66 patients for analysis. Direct procedural cost was significantly greater in the MMAE group compared with the open surgery group ($38,255 ± $11,859 vs. $11,206 ± $7888; P < 0.001). Medication cost also was greater in the MMAE group ($6888 ± $6525 vs. $4291 ± $3547; P = 0.048). No significant difference was found in costs for intensive care unit care, pharmacy, therapy, laboratory values, and the emergency department. Imaging costs and other miscellaneous costs (e.g., wound care, preoperative, and postanesthesia care unit) were greater in the open surgery group (P < 0.05). Total hospitalization cost was not significantly different between the 2 groups ($60,598 ± 61,315 vs. $71,569 ± $37,813 for open surgery and MMAE respectively, P = 0.385). No significant differences in number of follow ups or total costs for follow up were found (P > 0.05).

CONCLUSIONS

Open surgery and MMAE offer an overall equivalent cost-profile for cSDH treatment when matching for potential cost confounders. Direct procedural costs are greater in MMAE; however, total hospitalization costs and follow up costs are not significantly different.

Republished: Resolution of an enlarging subdural haematoma after contralateral middle meningeal artery embolisation

A man in his 50s presented 1 month after an automobile accident with worsening headaches and an enlarging chronic left subdural haematoma (SDH). He underwent left middle meningeal artery (MMA) embolisation. Due to tortuosity at its origin, we were unable to catheterise the MMA distally. Only proximal coil occlusion at the origin was performed. Follow-up interval head CT showed an increase in the size of the SDH with new haemorrhage, worsening mass effect and midline shift. However, he remained neurologically intact. Contralateral embolisation of the right MMA was performed with a liquid embolic agent. His headaches improved, and a follow-up head CT 3 months later showed near-complete resolution of the SDH.

Middle meningeal artery embolisation: The review of a new treatment for chronic subdural hematomas

Background

This is a literature review aiming to provide an update about the recent findings related to the efficacy of middle meningeal artery embolization (MMAE) in the treatment of chronic subdural hematomas (cSDHs), comparison with conventional therapy and deduction of the current recommendations and indications.

Methods

The literature is reviewed using a search through the PubMed index using keywords. Studies are then screened, skimmed, and thoroughly read. 32 studies fulfilled the inclusion criteria and are included in the study.

Results

Five indications for the application of MMA embolization (MMAE) are deducted from the literature. The usage as a preventive measure after surgical treatment of symptomatic cSDHs in patients with a high risk of recurrence and the usage as a standalone procedure has been the most common reasons for indication of this procedure. Rates of failures for the aforementioned indications have been 6.8% and 3.8%, respectively.

Conclusion

The safety of MMAE as a procedure is regarded as a general theme in the literature and can be considered for future applications. Usage of this procedure in clinical trials with more patient segregation and timeframe assessment relative to surgical intervention are recommendations of this literature review.

Predictors of Subsequent Intervention After Middle Meningeal Artery Embolization for Treatment of Subdural Hematoma: A Nationwide Analysis

BACKGROUND

Middle meningeal artery (MMA) embolization has recently emerged as an effective technique to treat subdural hematomas (SDHs). Studies to date have been limited, largely, to single-center studies with limited follow-up and have not assessed subsequent surgical interventions and factors associated with these interventions.

OBJECTIVE

To evaluate rates of retreatment for SDH after MMA embolization and patient-specific factors that may be important predictors for these interventions.

METHODS

Using an all-payer claims database, Mariner, patients who underwent MMA embolization between January 2010 and October 2020 after the diagnosis of SDH were identified. Rates of post-MMA embolization surgical interventions, including craniotomy and burr hole drainage, were accessed within 5 years following. Patient-specific contributors to the rates of these interventions were studied using Gaussian logistic regression models.

RESULTS

A total of 322 patients were included. Of this cohort, 55 (17.1%) required subsequent intervention within 5 years, with 36 (11.2%) receiving burr hole evacuation and 19 (5.9%) receiving craniotomy. Factor Xa inhibitor use was independently associated with subsequent interventions after MMA embolization procedures (odds ratio: 1.20 [95% CI: 1.02-1.40]). Of the other patient factors evaluated, including age, sex, comorbidity status, and use of vitamin K antagonists, antiplatelets, and factor Xa inhibitors, none were found to be significantly associated with future interventions.

CONCLUSION

Although previous literature has shown MMA embolization to be safe and successful in preventing recurrent SDH, patients undergoing this procedure still carry a risk of future interventions. Patients taking factor Xa inhibitors are at especially high risk of subsequent intervention after MMA embolization.

Middle Meningeal Artery Embolization for the Management of Chronic Subdural Hematomas: A New-Old Treatment

Chronic subdural hematoma (cSDH) is defined as a subdural collection of blood on CT imaging that tends to persist and gradually increase in volume over time, with components that are hypodense or isodense compared to the brain. There are no proven guidelines for the management of patients with cSDH. Surgical approaches included burr hole, twist drill hole, and craniotomy-based evacuations. Outcomes after surgical removal is generally favorable, but cSDH tends to recur after the initial evacuation.Middle meningeal artery (MMA) embolization has been gaining increasing popularity among the treatments of cSDH. This is largely due to a growing population of patients with cSDH who are refractory to other treatments or in patients who present with multiple comorbidities or who are taking antiplatelet and anticoagulant medications. The goal of middle meningeal artery (MMA) embolization is to devascularize subdural membranes associated with SDH so that the balance between continued leakage and reabsorption is shifted toward reabsorption.We discuss our clinical and technical approach to cSDH treated with perioperative embolization of the MMA.

Onyx Versus Particles for Middle Meningeal Artery Embolization in Chronic Subdural Hematoma

BACKGROUND

Middle meningeal artery (MMA) embolization has recently emerged as a treatment option for chronic subdural hematoma (cSDH). It is considered a simple and potentially safe endovascular procedure.

OBJECTIVE

To compare between 2 different embolic agents; onyx (ethylene vinyl alcohol) and emboparticles (polyvinyl alcohol particles-PVA) for endovascular treatment of cSDH.

METHODS

A retrospective analysis of all patients who underwent MMA embolization for cSDH treatment in 2 comprehensive centers between August 2018 and December 2021. Primary outcomes were failure of embolization and need for rescue surgical evacuation.

RESULTS

Among 97 MMA embolizations, 49 (50.5%) received onyx and 48 (49.5%) received PVA. The presence of acute or subacute on cSDH was higher in the PVA group 11/49 (22.5%) vs 30/48 (62.5%), respectively, P < .001. There were no significant differences between both groups regarding failure of embolization 6/49 (12.2%) vs 12/48 (25.0%), respectively, P = .112, and need of unplanned rescue surgical evacuation 5/49 (10.2%) vs 8/48 (16.7%), respectively, P = .354. Hematoma thickness at late follow-up was significantly smaller in the PVA group 7.8 mm vs 4.6 mm, respectively; P = .017.

CONCLUSION

Both onyx and PVA as embolic agents for cSDH can be used safely and have comparable clinical and surgical outcomes.

Management of Chronic Subdural Hematoma: A Systematic Review and Component Network Meta-analysis of 455 Studies With 103 645 Cases

BACKGROUND

Chronic subdural hematoma (CSDH) is a common neurosurgical condition with a high risk of recurrence after treatment.

OBJECTIVE

To assess and compare the risk of recurrence, morbidity, and mortality across various treatments for CSDH.

METHODS

A systematic review and meta-analysis was performed. PubMed/MEDLINE, EMBASE, SCOPUS, and Web of Science were searched from January 01, 2000, to July 07, 2021. The primary outcome was recurrence, and secondary outcomes were morbidity and mortality. Component network meta-analyses (CNMAs) were performed for surgical and medical treatments, assessing recurrence and morbidity. Incremental risk ratios (iRRs) with 95% CIs were estimated for each component.

RESULTS

In total, 12 526 citations were identified, and 455 studies with 103 645 cases were included. Recurrence occurred in 11 491/93 525 (10.8%, 95% CI 10.2-11.5, 418 studies) cases after surgery. The use of a postoperative drain (iRR 0.53, 95% CI 0.44-0.63) and middle meningeal artery embolization (iRR 0.19, 95% CI 0.05-0.83) reduced recurrence in the surgical CNMA. In the pharmacological CNMA, corticosteroids (iRR 0.47, 95% CI 0.36-0.61) and surgical intervention (iRR 0.11, 95% CI 0.07-0.15) were associated with lower risk. Corticosteroids were associated with increased morbidity (iRR 1.34, 95% CI 1.05-1.70). The risk of morbidity was equivalent across surgical treatments.

CONCLUSION

Recurrence after evacuation occurs in approximately 10% of cSDHs, and the various surgical interventions are approximately equivalent. Corticosteroids are associated with reduced recurrence but also increased morbidity. Drains reduce the risk of recurrence, but the position of drain (subdural vs subgaleal) did not influence recurrence. Middle meningeal artery embolization is a promising treatment warranting further evaluation in randomized trials.

Subdural evacuation port system and middle meningeal artery embolization for chronic subdural hematoma: a multicenter experience

OBJECTIVE

Middle meningeal artery (MMA) embolization and the Subdural Evacuation Port System (SEPS) are minimally invasive treatment paradigms for chronic subdural hematoma (cSDH). Although SEPS offers acute decompression of local mass effect from a cSDH, MMA embolization has been shown to reduce the rate of cSDH recurrence. In combination, these procedures present a potentially safer strategy to a challenging pathology. The authors present a multi-institutional retrospective case series that assessed the safety, efficacy, and complications of SEPS and MMA embolization for cSDH.

METHODS

A retrospective review was performed of patients who underwent SEPS placement and MMA embolization for cSDH between 2018 and 2021 at three institutions.

RESULTS

One hundred patients with 136 cSDHs and a median age of 73 years underwent both SEPS placement and MMA embolization. Initial Glasgow Coma Scale scores were between 14 and 15 in 81% of patients and between 9 and 13 in 14%. The median initial midline shift (MLS) was 7 mm, with subdural hematoma (SDH) in the left hemisphere (lh) in 30% of patients, right hemisphere (rh) in 34%, and bilateral hemispheres in 36%. Follow-up was available for 86 patients: 93.4% demonstrated decreased MLS, and all patients with lhSDH and rhSDH demonstrated progressive decrease in SDH size. The overall complication rate was 4%, including 1 case of facial palsy and 3 cases of iatrogenic acute SDH. Two subjects (2%) required craniotomy for hematoma evacuation. The rate of good functional outcomes, with modified Rankin Scale (mRS) score < 2, was 89% on final follow-up and the overall mortality rate was 2%. A good mRS score on admission was associated with increased odds of functional improvement at follow-up (p < 0.001).

CONCLUSIONS

SEPS placement with MMA embolization for cSDH can be done safely and effectively reduces cSDH size with minimal perioperative morbidity.

Swedish trial on embolization of middle meningeal artery versus surgical evacuation in chronic subdural hematoma (SWEMMA)—a national 12-month multi-center randomized controlled superiority trial with parallel group assignment, open treatment allocation and blinded clinical outcome assessment

Background

Chronic subdural hematoma (cSDH) is one of the most common neurosurgical disorders and the incidence is rising. The routine treatment is neurosurgical hematoma evacuation, which is associated with recurrence rates up to 10–25%. In recent years, endovascular embolization of the middle meningeal artery (eMMA) has garnered much attention due to recurrence rates as low as < 5%. Several randomized controlled trials are planned or ongoing. In most of these trials, conventional neurosurgical treatment with or without adjunctive endovascular embolization is compared. The proposed trial aims to conduct a head-to-head comparison between neurosurgical and endovascular treatment as stand-alone treatments.

Methods

The trial is academically driven and funded within existing public healthcare systems and infrastructure. Patients with uni- or bilateral cSDH, presenting with mild-to moderate symptoms, and admitted to neurosurgery on clinical grounds will be offered participation. Subjects are randomized 1:1 between conventional neurosurgical treatment (control) and endovascular embolization of the middle meningeal artery (intervention). Primary endpoint is reoperation due to clinically and/or radiologically significant recurrence within 3 months. Secondary endpoints include safety, technical success rate, neurological disability, and quality of life.

Discussion

There are mounting retrospective data suggesting eMMA, as sole treatment or as an adjunctive to neurosurgery for cSDH, is safe and effective with a reoperation rate lower than neurosurgical hematoma evacuation alone. If randomized controlled trials confirm these findings, there is a potential for a paradigm shift in the treatment of cSDH where a minimally invasive procedure can replace open surgery in a large and oftentimes old and fragile patient cohort.

Trial registration

ClinicalTrials.gov, ClinicalTrials.gov Identifier NCT05267184. Registered March 4, 2022.

Middle Meningeal Artery Embolization with Isolated Use of Coils for Treatment of Chronic Subdural Hematomas: A Case Series

BACKGROUND

Middle meningeal artery embolization (MMAE) is a novel approach for treatment of chronic subdural hematoma (cSDH). Studies comparing different procedural techniques for MMAE are lacking. It is unclear whether isolated use of coils results in suboptimal outcomes compared to when particle embolization is also performed. The objectives of this study are to describe the outcomes of coil-only MMAE and compare them with those of combined use of coils and particles.

METHODS

A single-institution retrospective study of cSDH cases treated by MMAE was performed. Clinical outcomes, need for rescue surgery, and changes in hematoma's size were compared between the coil-only and coil + particle groups.

RESULTS

Ninety-four hematomas in 78 patients were included. Twelve cases were treated by a coil-only MMAE procedure, often due to presence of dangerous ophthalmic collaterals. No treatment-related complications were observed in the coil-only group. There was no significant difference between the coil-only and coil + particle groups in baseline hematoma axial thickness, volume, midline shift, and duration of follow-up. The rate of need for rescue surgery was similar between the 2 groups (8.3% vs. 8.5%; P = 0.98). Coiling alone resulted in a similar percentage of reduction in cSDH volume (68.3% vs. 71.8%; P = 0.8) and rate of achieving ≥50% reduction in volume (81.8% vs. 76.3%; P = 0.68) compared to coils + particles.

CONCLUSIONS

Isolated use of coils for endovascular treatment of cSDHs can be as effective as adjunct use of particle embolization. This method eliminates the risks of cranial nerve and visual complications associated with MMAE, can prevent procedural abortion due to presence of dangerous anastomoses, and reduces the technical complexity of the procedure.

In-hospital mortality rates, complication rates, length of stay, and total costs of >14,000 chronic subdural hematomas treated in the U.S. between 2016 and 2020: Query of the premier health-care database

Background:

With the drastically aging population in the U.S., chronic subdural hematomas (cSDHs) are projected to represent the most common neurosurgical diagnosis requiring treatment within the next two decades. There is lack of contemporary outcome data in patients treated for nontraumatic and nonacute subdural hematoma. We aim to portray current mortality rates, complication rates, length of stay, and costs associated with inpatient cSDH care.

Methods:

The Premier Health-care Database, Premier Inc., Charlotte/NC was queried for encounters October 2016–December 2020 with the ICD-10 diagnoses of nontraumatic nonacute subdural hematoma as the principal diagnosis among patients age ≥40 years. Per database in-hospital mortality is defined as mortality in an inpatient who is not discharged. Complications represent medical conditions not present on admission that affects mortality, length of stay, and costs within the database.

Results:

The query identified 14,136 inpatient encounters. Between October 2016 and December 2020, in-hospital mortality rates averaged 10.9% in the medical group (MG) and 3.6% in the surgical group (SG) (P < 0.001). Complication rates averaged between 8.9 % in the MG and 19.9% in the SG (P < 0.001). LOS averaged 3.0 days in the MG and 5.7 days in the SG (P < 0.001). Total costs averaged $ 10,233 in the MG and $ 26,658 in the SG.

Conclusion:

The standardized outcomes presented represent an objective benchmark of contemporary cSDH treatment outcomes in the U.S. With the projected substantial increase of cSDH cases within the next decades, new treatment strategies such as middle meningeal embolization need to be explored and outperform current outcome metrics.

Recent Advances and Future Directions in Middle Meningeal Artery Embolization for Chronic Subdural Hematomas

PURPOSE OF REVIEW

The purpose of this review is to present a brief background on chronic subdural hematomas (cSDH), middle meningeal artery (MMA) embolization, and its role in decreasing recurrence of cSDH. A review of the most up-to-date literature should demonstrate the efficacy of this procedure.

RECENT FINDINGS

The latest data shows that MMA embolization is a safe procedure, with low complication rates and low recurrence rates. While cSDH managed with surgical evacuation can have a recurrence rate upwards of 30%, MMA embolization alone or as an adjunct to surgery decreases recurrence to less than 5% in most studies. MMA embolization can be especially useful in high-risk populations such as the elderly, patients on anti-platelet medication, and those with coagulopathies. It can also be done awake, done without general anesthesia, and is significantly less invasive than traditional surgical techniques. In reviewing the literature on MMA embolization, it is clear that there are numerous retrospective studies and systematic reviews demonstrating its safety and efficacy, and some prospective dual-arm studies that present novel information. The numerous clinical trials that are currently underway should help to further establish MMA embolization as standard of care in the management of cSDH.

Embolization of the Middle Meningeal Artery for the Treatment of Chronic Subdural Hematoma: A Path Less Travelled So Far

Introduction  Chronic subdural hematoma (CSDH) is relatively common and usually encountered in elderly population. With steady increase in life expectancy, incidence of CSDH also is bound to increase proportionately. Though surgery is the treatment of choice and relatively a simpler procedure, recurrence is a cause of concern. Embolization of the middle meningeal artery (MMA) is a newly evolving treatment modality in CSDH and offers hope in some of the recently published case series. Materials and Methods  Five cases of CSDH were subjected to embolization of MMA over a period from October 2019 to July 2020. Among them, it was employed for treatment in four cases after at least two recurrences following surgery, and in one case, it was done as the patient was not fit for surgery. All procedures were done under general anesthesia and polyvinyl alcohol (PVA) particles were used for embolization. Follow-up of the patients were done with computed tomography brain at 4 weeks and after 6 months of the procedure. Results  There was no incidence of recurrence in our series. Furthermore, embolization per se did not cause any complication or side effect which could be directly attributable to the procedure itself. Conclusion  In carefully selected patients based on clinical profile and angiographic findings, MMA embolization can be an effective modality for the treatment in CSDH.

Management of Chronic Subdural Hematoma in Patients Requiring Therapeutic Anticoagulation

INTRODUCTION

A common risk factor of chronic, nontraumatic subdural hematoma (SDH) is anticoagulation therapy. Anticoagulation is generally held in patients who develop SDH, but this can lead to thromboembolic events. While prior studies have reported the clinical outcomes of patients with anticoagulation-related SDH, there remains little evidence regarding ongoing anticoagulation treatment.

CASE REPORT

We report the management of 2 patients who developed anticoagulation-related SDH and underwent middle meningeal artery (MMA) embolization and successful reinitiation of anticoagulation therapy. In both patients, we conservatively managed anticoagulation with heparin and/or enoxaparin as a bridge to warfarin after MMA embolization. Follow-up computed tomography head revealed interval decrease of SDH and stable neurological status.

CONCLUSIONS

These cases provide anecdotal evidence of a challenging clinical scenario where there is a necessary indication for therapeutic anticoagulation (ie, venous sinus thrombosis or atrial appendage thrombus) and comorbid SDH. Endovascular MMA embolization may be an effective adjunct therapy for clinical scenarios in patients with SDH and an urgent indication for anticoagulation. Longer follow-up, prospective series, and future randomized clinical trials are needed to objectively assess outcomes in this clinically challenging patient population.