Middle meningeal artery patency after surgical evacuation for chronic subdural hematoma.

BACKGROUND: Chronic subdural hematoma (CSDH) often requires surgical evacuation, but recurrence rates remain high. Middle meningeal artery (MMA) embolization (MMAE) has been proposed as an alternative or adjunct treatment. There is concern that prior surgery might limit patency, access, penetration, and efficacy of MMAE, such that some recent trials excluded patients with prior craniotomy. However, the impact of prior open surgery on MMA patency has not been studied. METHODS: A retrospective analysis was conducted on patients who underwent MMAE for cSDH (2019-2022), after prior surgical evacuation or not. MMA patency was assessed using a six-point grading scale. RESULTS: Of the 109 MMAEs (84 patients, median age 72 years, 20.2% females), 58.7% were upfront MMAEs, while 41.3% were after prior surgery (20 craniotomies, 25 burr holes). Median hematoma thickness was 14 mm and midline shift 3 mm. Hematoma thickness reduction, surgical rescue, and functional outcome did not differ between MMAE subgroups and were not affected by MMA patency or total area of craniotomy or burr-holes. MMA patency was reduced in the craniotomy group only, specifically in the distal portion of the anterior division (p = 0.005), and correlated with craniotomy area (p < 0.001). CONCLUSION: MMA remains relatively patent after burr-hole evacuation of cSDH, while craniotomy typically only affects the frontal-distal division. However, MMA patency, evacuation method, and total area do not affect outcomes. These findings support the use of MMAE regardless of prior surgery and may influence future trial inclusion/exclusion criteria. Further studies are needed to optimize the timing and techniques for MMAE in cSDH management.

Therapeutic efficacy of drilling drainage combined with intraoperative middle meningeal artery occlusion in the management of chronic subdural hematoma: a clinical study.

BACKGROUND: The bone holes in the skull during surgical drainage were accurately located at the site of the MMA. The MMA was severed, and the hematoma was removed intraoperatively; furthermore, surgical drainage removed the pathogenic factors of CSDH. This study aimed to describe and compare the results of the new treatment with those of traditional surgical drainage, and to investigate the relevance of this approach. METHODS: From December 2021 to June 2023, 72 patients were randomly assigned to the observation group and the control group. The control group was treated with traditional surgical drainage, while the observation group was treated with DSA imaging to accurately locate the bone holes drilled in the skull on the MMA trunk before traditional surgical drainage. The MMA trunk was severed during the surgical drainage of the hematoma. The recurrence rate, time of indwelling drainage tube, complications, mRS, and other indicators of the two groups were compared, and the changes of cytokine components and imaging characteristics of the patients were collected and analyzed. RESULTS: Overall, 27 patients with 29-side hematoma in the observation group and 45 patients with 48-side hematoma in the control group were included in the study. The recurrence rate was 0/29 in the observation group and 4/48 in the control group, indicating that the recurrence rate in the observation group was lower than in the control group (P = .048). The mean indwelling time of the drainage tube in the observation group was 2.04 ± 0.61 days, and that in the control group was 2.48 ± 0.61 days. The indwelling time of the drainage tube in the observation group was shorter than in the control group (P = .003). No surgical complications were observed in the observation group or the control group. The differences in mRS scores before and after operation between the observation group and the control group were statistically significant (P < .001). The concentrations of cytokine IL6/IL8/IL10/VEGF in the hematoma fluid of the observation and control groups were significantly higher than those in venous blood (P < .001). After intraoperative irrigation and drainage, the concentrations of cytokines (IL6/IL8/IL10/VEGF) in the subdural hematoma fluid were significantly lower than they were preoperatively. In the observation group, the number of MMA on the hematoma side (11/29) before STA development was higher than that on the non-hematoma side (1/25), and the difference was statistically significant (P = .003). CONCLUSION: In patients with CSDH, accurately locating the MMA during surgical trepanation and drainage, severing the MMA during drainage, and properly draining the hematoma, can reduce the recurrence rate and retention time of drainage tubes, thereby significantly improving the postoperative mRS Score without increasing surgical complications.

Letter to the editor: "Therapeutic efficacy of drilling drainage combined with intraoperative middle meningeal artery occlusion in the management of chronic subdural hematoma: a clinical study".

This letter addresses the research presented by Sun et al. on the integration of digital subtraction angiography (DSA) with conventional surgical drainage for chronic subdural hematoma (CSDH), focusing on precision in targeting the middle meningeal artery (MMA). The study demonstrates a reduction in hematoma recurrence and drainage tube indwelling times, highlighting the procedural benefits without added complications. The letter suggests further research directions, including the potential for personalized surgical approaches based on MMA anatomy variations, and emphasizes the importance of this technique in enhancing neurosurgical outcomes.

Facial nerve palsy after middle meningeal artery embolization for chronic subdural hematoma: a case report.

Middle meningeal artery embolization (MMAE) has emerged as a safe and efficacious alternative to surgery for the treatment of new or recurrent chronic subdural hematoma (CSDH). Several complications such as facial palsy may suddenly occur even in the absence of evident dangerous anastomoses in the angiogram. We herein present a case-report of left facial nerve palsy after MMAE.

Middle Meningeal Artery Embolization in Pediatric Patients.

BACKGROUND: Middle meningeal artery (MMA) embolization has been increasingly applied in adult populations for the treatment of chronic subdural hematomas (cSDH). There is a paucity of literature on the indications, safety, and outcomes of MMA embolization in the pediatric population. SUMMARY: A systematic literature review on pediatric patients undergoing MMA embolization was performed. We also report the case of successful bilateral MMA embolization for persistent subdural hematomas following resection of a juvenile pilocytic astrocytoma. Persistent bilateral subdural hematomas following resection of a large brain tumor resolved following MMA embolization in a 13-year-old male. Indications for MMA embolization in the pediatric literature included cSDH (6/13, 46.2%), treatment or preoperative embolization of arteriovenous fistula or arteriovenous malformation (3/13, 23.1%), preoperative embolization for tumor resection (1/13, 7.7%), or treatment of acute epidural hematoma (1/13, 7.7%). Embolic agents included microspheres or microparticles (2/13, 15.4%), Onyx (3/13, 23.1%), NBCA (3/13, 23.1%), or coils (4/13, 30.8%). KEY MESSAGES: Whereas MMA embolization has primarily been applied in the adult population for subdural hematoma in the setting of cardiac disease and anticoagulant use, we present a novel application of MMA embolization in the management of persistent subdural hematoma following resection of a large space-occupying lesion. A systematic review of MMA embolization in pediatric patients currently shows efficacy; a multi-institutional study is warranted to further refine indications, timing, and safety of the procedure.

[Middle meningeal artery embolization to treat acute epidural haematoma, case report and literature review]. / Akut epiduralis haematoma kezelése arteria meningea media embolisatióval, esetismertetés és irodalmi áttekintés.

The treatment of acute epidural haematoma is surgery as soon as possible, elimination of the source of bleeding and evacuation of the haematoma. In case of small epidural haematoma, strict neurological and radiological follow-up is necessary. In a significant percentage of cases, open surgery must also be performed within a few days. In case of small epidural haematomas, embolization of the middle meningeal artery is considered as an alternative solution. We review the literature on middle meningeal artery embolization and present our first treatment. Our case report is the first European report about an acute epidural haematoma which was treated by embolization of middle meningeal artery. Our case study is the first report in which a patient was treated with both open surgery and endovascular treatment for acute epidural haematoma within a year.

Angiographic classification of chronic subdural hematoma.

Background and purpose:

Chronic subdural hematoma (cSDH) is a challenging pathology with high recurrence rate after surgical treatment and may seriously affect the patient’s quality of life. Membrane formation with angiogenesis plays an important role in the evolution of the disease, providing a promising target for endovascular therapy. Our goal is to categorize angiographic patterns of chronic subdural hematoma for standardized reporting purposes.

In our retrospective analysis of prospective data collection, we analyzed angiographic properties of all high recurrence risk patients with cSDH, who were treated by embolization in our hospital between February 2019 and June 2020. Altogether 17 patients were included in the analysis. 

Based on superselective angiography of the middle meningeal artery (MMA) in the two standard, AP and lateral views, three distinct categories of dural supply were defined: normal vascular pattern (Grade I), cottonwool appearance without enlargement of the MMA branches (Grad II) and strong cottonwool like staining with dilatative remodelling of the MMA branches (Grade III).

The proposed grading system of the angiographic appearance of cSDH, representing the pathophysiological evolution of the disease should be correlated to therapeutic success rates and could be applied in future clinical studies.

[Az arteria meningea media embolisatio szerepe a krónikus subduralis haematoma kezelési algoritmusában, legújabb evidenciák és saját tapasztalataink]. / Az arteria meningea media embolisatio szerepe a krónikus subduralis haematoma kezelési algoritmusában, legújabb evidenciák és saját tapasztalataink.

Chronic subdural hematoma is one of the most common diseases requiring a neurosurgical operation that affect elderly and fragile patients. In addition to standard neurosurgical operations (trepanation and craniotomy), embolization of the meningeal artery media is an alternative solution. Several review aerticles have confirmed the very high rate of success and safety of the endovascular treatment. We present the technical details and results of our 10 consecutive selective media meningeal artery embolization procedures for residual chronic subdural hematomas. Our interventions were performed without complications and all resulted in complete recovery. 

Middle Meningeal Artery Embolization in the Management of Chronic Subdural Hematoma: a Comprehensive Review of Current Literature.

PURPOSE OF REVIEW: Chronic subdural hematoma (cSDH) is a common intracranial hemorrhagic disorder with a high incidence rate among the elderly. While small, asymptomatic cSDH may resolve spontaneously, surgical intervention has been the treatment of choice for larger, symptomatic cases. Surgical evacuation of cSDH may be associated with high rates of recurrence, and even asymptomatic cSDH cases tend to progress. Over the last few years, middle meningeal artery (MMA) embolization has proven to be a safe non-invasive treatment of choice with favorable outcomes and a low recurrence rate. The ensuing paper discusses current treatment modalities for cSDH and reviews existing literature on the anatomy of MMA and its embolization as a treatment option for cSDH. RECENT FINDINGS: Recent studies show that traumatic head injury leading to subdural hemorrhage can induce neovascularization that may initiate a cycle of recurrent subdural hematoma. Distal branches of MMA supply blood to the dural layers. Several studies have revealed that embolization of the MMA can stop the neovascularization process and blood flow. In addition, patients who underwent MMA embolization had a significantly quicker brain re-expansion and lower recurrence rate. Although the management of cSDH is still very much a dilemma, recent research findings bring MMA embolization to light as a promising treatment alternative and adjunctive therapy.

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.

Grading Embolization of Middle Meningeal Artery for Chronic Subdural Hematoma.

BACKGROUND AND PURPOSE: Embolization of middle meningeal artery (EMMA) is a relatively new treatment for chronic subdural hematoma (CSDH). To date, an objective method that assesses or describes the extent of EMMA for the treatment of CSDH does not exist. Recently, the concept of a novel grading scale for EMMA in patients with CSDH has emerged. However, this has not been applied to a clinical case setting and inter-rater reliability has not yet been studied. The purpose of this study was to validate the grading scale in clinical practice and to assess for inter-rater reliability. MATERIALS AND METHODS: We retrospectively examined consecutive patients who underwent EMMA for CSDH. Patients were included if the whole head angiogram from common carotid as well as external carotid arteries before and after EMMA were available in the arterial, capillary as well as venous phases. Two independent readers, each with more than 5 years of experience in independent practice, assessed the angiograms for the grading of EMMA and assigned a score ranging between 0 and 3. The grading score between the two readers were compared using Cohen's Kappa score to assess the inter-rater reliability. RESULTS: In 19 patients, we found that EMMA had no periprocedural morbidity and mortality. The number of cases in each EMMA grading score category are as follows: 0 n =1; 1 n =3; 2 n =1; and 3 n =10. There was substantial inter-rater reliability for the assessment of grading of EMMA (Kappa = 0.74). CONCLUSIONS: The novel EMMA grading scheme demonstrated substantial inter-rater reliability and appears promising.

Ophthalmic artery arising from the external carotid artery system: the middle meningeal artery in South African patients.

BACKGROUND: The ophthalmic artery is the first branch of the internal carotid artery. It arises from the supraclinoid segment of the internal carotid artery within the subarachnoid space and enters the orbit via the optic canal. However, due to complex embryogenesis, the ophthalmic artery can arise from different parts of the internal carotid artery or the distal branches of the external carotid artery. This is usually associated with a variation in the course of the ophthalmic artery through the superior orbital fissure instead of coursing through the optic canal. The ophthalmic artery and its branches vascularise the eyeball and its contents. Consequently, information about its morphologic variation is essential for treating clinical conditions such as central retinal artery occlusion, retinoblastoma chemoembolization, and ophthalmic artery aneurysm. CASE PRESENTATION: We report on two cases of the ophthalmic artery arising from the middle meningeal artery in one adult (33-year-old Indian female) and one pediatric (2-year-old African male) South African patient examined by digital subtraction angiography. The patients were diagnosed with arteriovenous malformations and bilateral retinoblastoma, respectively. CONCLUSIONS: The ophthalmic artery plays a vital role in vision generation. Thus, its anatomy is of clinical interest to neurosurgeons, ophthalmologists, and interventional radiologists.

Comparative outcomes of middle meningeal artery embolization with statins versus embolization alone in the treatment of chronic subdural hematoma: a systematic review and meta-analysis.

Chronic subdural hematoma (cSDH) is common among the elderly, with surgical evacuation as a prevalent treatment, facing recurrence rates up to 30%. Recently, middle meningeal artery embolization (MMAE) has emerged as a promising approach, offering reduced treatment failures and recurrence rates. Additionally, statins, known for their anti-inflammatory properties, have been considered as a potential adjunctive or sole treatment for cSDH. However, the combination of MMAE with statins remains understudied. This systematic review and meta-analysis aims to evaluate the comparative outcomes of MMAE with statins versus MMAE alone in the treatment of cSDH. A comprehensive systematic search of the PubMed, Web of Science, and SCOPUS databases was conducted. Inclusion criteria were: studies published in English between the dates of inception of each database and August 2023, studies comparing the treatment of cSDH with either MMAE + statin or MMAE alone were included. Main outcome measures were complete resolution of the hematoma at follow-up and the recurrence rates. Two studies comprising 715 patients were included; 408 patients underwent MMAE + statin; and 307 underwent MMAE alone. MMAE + statin was not significantly superior to MMAE alone in achieving complete resolution of the hematoma at follow-up (RR: 0.99; CI: 0.91 to 1.07, P = 0.84), nor was it a significant difference in rates of recurrence (RR: 1.35; CI: 0.83 to 2.17, P = 0.21) between the two groups. MMAE + statin did not demonstrate significant superiority over MMAE alone for achieving complete resolution and decreasing the recurrence rates in cSDH patients. Further research with larger, randomized studies may be required to fully elucidate the potential synergistic effects of MMAE and statins in this patient population.

Middle meningeal artery embolization and pediatric chronic subdural hematoma: a systematic review of the literature.

Chronic subdural hematoma (CSDH) is a disease commonly found in the elderly and not a typical finding in pediatric population. History of shunt surgery, child abuse, and blood disorder are some of the common causes of pediatric CSDH (pCSDH). There is growing evidence about the role of middle meningeal artery embolization (MMAE) to manage CSDH in the elderly population with a high risk of rebleeding. However, the evidence in the pediatric population is still sparse. A systematic literature search was conducted on PubMed, Scopus, and Web of Science database from January, 2023, to March, 2023. Search strings were generated based on the combination of modified search terms, such as CSDH, MMA embolization, and child. Risk of bias was assessed using the Cochrane Risk of Bias in Nonrandomized Study for Intervention. Nine articles were included in this review. The success rate of MMA embolization in pediatric CSDH was 88.8%. Histories of ventriculoperitoneal shunt, blood coagulation disorder, and trauma were the causes of CSDH. Time to achieve success was varied from 2 to 9 months. No study with low risk of bias was found. This systematic review found no high-quality evidence regarding the role of MMA embolization in the management of pCSDH. However, due to its high success rate, MMAE could be a promising approach to treat pCSDH.

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.

Non-surgical management of chronic subdural hematoma: insights and future perspectives from an international survey including neurosurgeons from 90 countries worldwide.

BACKGROUND: Chronic subdural hematoma (cSDH) is one of the most common neurosurgical conditions. Although surgical evacuation is still the gold standard for treatment, recent advances have led to the development of other management strategies, such as medical therapies and endovascular middle meningeal artery (MMA) embolization. Through this international survey, we investigated the global trends in cSDH management, focusing on medical and endovascular treatments. DESIGN AND PARTICIPANTS: A 14-question, web-based, anonymous survey was distributed to neurosurgeons worldwide. RESULTS: Most responders do not perform MMA embolization (69.5%) unless for specific indications (29.6%). These indications include residual cSDH after surgical evacuation (58.9%) or cSDH in patients on antiplatelet medications to avoid surgical evacuation (44.8%). Survey participants from teaching versus non-teaching hospitals (p = 0.002), public versus private hospitals (p = 0.022), and Europe versus other continents (p < 0.001) are the most users of MMA embolization. A large number of participants (51%) declare they use a conservative/medical approach, mainly to avoid surgery in patients with small cSDH (74.8%). CONCLUSIONS: This survey highlights the current trends of cSDH management, focusing on conservative and MMA embolization treatment strategies. Most responders prefer a conservative approach for patients with small cSDHs not requiring surgical evacuation. However, in higher-risk scenarios such as residual hematomas after surgery or patients on antiplatelet medications, MMA embolization is regarded as a reasonable option by participants. Future studies should clarify the indications of MMA embolization, including appropriate patient selection and efficacy as a stand-alone procedure.

A case of meningioma originating from the lateral wall of the cavernous sinus.

Meningioma originating from the lateral wall of the cavernous sinus is rare with only two reported cases. A 67-year-old man presented with recent memory disturbance and partial seizure. Magnetic resonance imaging revealed a well-demarcated and homogeneously enhanced mass lesion originating from the lateral wall of the left cavernous sinus. Total tumor removal was performed through a combined epi- and intradural approach. Histological diagnosis was transitional meningioma. Postoperative course was uneventful. This combined approach was helpful for cranial nerve preservation, total tumor removal, and bleeding control from the feeder of the tumor.

Posterior inferior cerebellar artery originating from the posterior meningeal artery mimicking dural arteriovenous fistula.

PURPOSE: Many variations in the origin of the posterior inferior cerebellar artery (PICA) have been reported. To our knowledge, only one case of a PICA originating from the posterior meningeal artery (PMA) has been reported. METHODS: We describe a case with a PICA that was supplied retrograde from the distal segment of the PMA, mimicking a dural arteriovenous fistula on magnetic resonance angiography (MRA). RESULTS: A 31-year-old man was admitted to our hospital with a sudden occipital headache and nausea. MRA showed a hyperplastic left PMA, continuing to an abnormal vessel that was suspicious for venous drainage. Digital subtraction angiography revealed the left PMA originated from the extradural segment of the vertebral artery and then connected to the left PICA near the torcula. The cortical segment of the PICA flowed retrograde, which appeared as venous reflux on MRA. A second PICA originated from the extradural segment of the left vertebral artery and perfused the tonsillomedullary and televelotonsillar segment of the left PICA territory. CONCLUSION: We present an anatomical variant of the PICA mimicking a dural arteriovenous fistula. Digital subtraction angiography is useful for diagnosis of the cortical segment of the PICA flowing retrograde from the distal segment of the PMA because signal intensity in MRA of retrograde flow tends to decrease and diagnosis may be difficult. During endovascular treatment and open surgery, we should note that ischemic complications may occur due to the potential anastomosing channels between cerebral and dural arteries.

Migraine attacks are of peripheral origin: the debate goes on.

BACKGROUND: Despite the pervasiveness of migraine, the underlying pathophysiological mechanisms initiating migraine attacks are far from well understood and are matter of scientific debate. OBJECTIVE: In this narrative review, we discuss key evidence for that suggest a peripheral origin or central origin and provide directions for future studies that may provide further clarification. DISCUSSION: Migraine pathogenesis is considered to involve the trigeminovascular system, a term that encompasses the trigeminal nerve and its axonal projections to the intracranial blood vessels. Beyond any doubt both peripheral and central mechanisms are involved in migraine pathogenesis, but an unresolved question is the how the initial activation occurs in a migraine attack. Evidence favoring a peripheral origin of migraine attacks, i.e., initial events occur outside of the blood-brain barrier, include the importance of sensitization of perivascular sensory afferents early on in a migraine attack. Evidence favoring a central origin include the occurrence of prodromal symptoms, migraine aura, and activation of structures within the central nervous system early in and during a migraine attack. CONCLUSIONS: Both peripheral and central mechanisms are likely involved in a migraine attack, e.g., peripheral nociceptive input is necessary for pain transmission and cortical activity is necessary for pain perception. Yet, the debate of whether migraine attacks are initiated a peripheral or central site remains unresolved. The increased focus on prodromal symptoms and on the development of a human model of migraine aura will possibly provide key arguments needed to answer this question in the near future. Until then, we cannot draw firm conclusions and the debate goes on. VIDEO LINK: Video recording of the debate held at the 1st International Conference on Advances in Migraine Sciences (ICAMS 2022, Copenhagen, Denmark) is available at: https://www.youtube.com/watch?v=NC0nlcKohz0 .

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.