Resumption of Antithrombotic Agents in Chronic Subdural Hematoma: A Systematic Review and Meta-analysis

Updates on the diagnosis and management of subdural hematoma

ABSTRACT

Intracranial hemorrhage is a potentially life-threatening condition categorized into four main groups by the location of bleeding: epidural, subdural, subarachnoid, and intraparenchymal. Subdural hematoma (SDH) is increasingly common as the population of older adults increases. Clinicians must recognize the typical presentations and order diagnostic imaging studies to make a timely diagnosis and referral to neurosurgery for definitive treatment. Understanding the pathophysiology and risk factors for chronic or expanding SDH informs decision-making in managing anticoagulants. Emerging treatments offer potential alternatives to the traditional evacuation of SDH by craniotomy, which remains the standard of care for most symptomatic patients.

Between a rock and a hard place: resumption of oral anticoagulant therapy after intracranial hemorrhage

Intracranial hemorrhage (ICH) is the most feared and lethal complication of oral anticoagulant (OAC) therapy. Resumption of OAC after ICH has long posed a challenge for clinicians, complicated by the expanding range of anticoagulant agents available in modern clinical practice, including direct OACs and, more recently, factor XI and XII inhibitors. A review of the current literature found support for resuming OAC in the majority of patients after ICH based on pooled retrospective data showing that resumption is associated with a lower risk of mortality and thromboembolism without a significantly increased risk of recurrent hemorrhage. The optimal time to resume OAC is less clear; however, the available evidence suggests that the composite risk of both recurrent hemorrhage and thromboembolism is likely minimized, somewhere between 4 and 6 weeks, after ICH in most patients. Specific considerations to guide the optimal resumption time in the individual patient include ICH location, mechanism, and anticoagulant class. Patients with mechanical heart valves and intracerebral malignancy represent high-risk groups who require more nuanced decision making. Here, we appraise the literature with the aim of providing a practical guide for clinicians while also discussing priorities for future investigation.

Safety and Effectiveness of an Enhanced Recovery Protocol in Patients Undergoing Burr Hole Evacuation for Chronic Subdural Hematoma

BACKGROUND AND OBJECTIVES

Enhanced recovery programs may be especially useful in patients with chronic subdural hematoma or hygroma (cSDH), who frequently exhibit frailty and multimorbidity. We aim to evaluate the real-world safety and effectiveness of an enhanced recovery protocol in this population.

METHODS

From a prospective registry, burr hole evacuations for cSDH carried out under the protocol (including early thromboprophylaxis, no flat bed rest, early mobilization without drain clamping, and early resumption of antithrombotic medication) were extracted, along with those procedures carried out within the past year before protocol change. Propensity score-based matching was carried out. A range of clinical and imaging outcomes were analyzed, including modified Rankin Scale as effectiveness and Clavien-Dindo adverse event grading as safety primary end points.

RESULTS

Per group, 91 procedures were analyzed. At discharge, there was no significant difference in the modified Rankin Scale among the standard and enhanced recovery groups (1 [1; 2] vs 1 [1; 3], P = .552), or in Clavien-Dindo adverse event grading classifications of adverse events (P = .282) or occurrence of any adverse events (15.4% vs 20.9%, P = .442). There were no significant differences in time to drain removal (2.00 [2.00; 2.00] vs 2.00 [1.25; 2.00] days, P = .058), time from procedure to discharge (4.0 [3.0; 6.0] vs 4.0 [3.0; 6.0] days, P = .201), or total hospital length of stay (6.0 [5.0; 9.0] vs 5.0 [4.0; 8.0] days, P = .113). All-cause mortality was similar in both groups (8.8% vs 4.4%, P = .289), as was discharge disposition (P = .192). Other clinical and imaging outcomes were similar too (all P > .05).

CONCLUSION

In a matched cohort study comparing perioperative standard of care with a novel enhanced recovery protocol focusing on evidence-based drainage, mobilization, and thromboprophylaxis regimens as well as changes to the standardized reuptake of oral anticoagulants and antiaggregants, no differences in safety or effectiveness were observed after burr hole evacuation of cSDH.

Factors Associated With Morbidity and Retreatment After Surgical Management of Nonacute Subdural Hematomas in Elderly Patients

Background

Preoperative identification of clinical, radiographic, and surgery-specific factors associated with nonacute subdural hematomas (SDHs) may enable clinicians to optimize the efficacy of the initial surgical intervention, improve outcomes, and decrease rates of surgical recurrence.

Methods

The authors identified patients aged ≥65 years who underwent surgical treatment of chronic, subacute, or mixed-density SDH at a level-1 trauma hospital over a ten-year period (2010-2019). Pre-and postoperative clinical, radiographic, and surgery-specific data were collected. Predictors of surgical recurrence as well as morbidity, mortality, and discharge disposition were analyzed.

Results

There were 268 nonacute SDHs treated surgically; 46 were chronic, 19 were subacute, and 203 were mixed density. Of these, 179 were treated with burr hole(s), 62 with miniature craniotomy, and 27 via a large craniotomy and removal of subdural membranes. Statin use was protective (OR 0.22; 95% CI 0.08, 0.60) against recurrence requiring reoperation. Preoperative use of antithrombotic agents was not significantly associated with increased recurrence requiring reoperation. Smaller preoperative hematoma thickness was associated with significantly lower mortality risk, whereas mixed-density hematomas, patient age, change in thickness after surgery, density, and presence of cisternal effacement were significantly associated with discharge disposition. Hematoma type was also associated with hospital and intensive care length of stay.

Conclusions

Our experience suggests that, in elderly patients, premorbid statin usage is associated with lower recurrence rates and preoperative antithrombotic use does not affect recurrence when appropriately reversed before surgery. Patient age, preoperative thickness, and hematoma type contribute to postoperative outcomes such as discharge disposition and length of stay.

Schulz J, Wiesmann M, Altiok E, Höllig A. Chronic Subdural Hematoma

BACKGROUND

Chronic subdural hematoma (cSDH) is typically a disease that affects the elderly. Neurosurgical evacuation is generally indicated for hematomas that are wider than the thickness of the skull. The available guidelines do not address the common clinical issue of the proper management of antithrombotic drugs that the patient has been taking up to the time of diagnosis of the cSDH. Whether antithrombotic treatment should be stopped or continued depends on whether the concern about spontaneous or postoperative intracranial bleeding, and a presumably higher rate of progression or recurrence, with continued medication outweighs the concern about a possibly higher rate of thrombotic complications if it is stopped.

METHODS

In this article, we review publications from January 2015 to October 2020 addressing the issue of the management of antithrombotics in patients with cSDH that were retrieved by a selective search in the Pubmed and EMBASE databases, and we present the findings of a cohort study of 395 patients who underwent surgery for cSDH consecutively between October 2014 and December 2019.

RESULTS

The findings published in the literature are difficult to summarize concisely because of the heterogeneity of study designs. Among the seven studies in which a group of patients on antithrombotics was compared with a control group, four revealed significant differences with respect to the risk of thromboembolic complications depending on previous antithrombotic use and the duration of discontinuation, while three others did not. In our own cohort, discontinuation of antithrombotics (including both plasmatic and antiplatelet drugs) was associated with thrombotic complications in 9.1% of patients.

CONCLUSION

These findings imply that the management of antithrombotics should be dealt with critically on an individual basis. In patients with cSDH who are at elevated risk, an early restart of antithrombotic treatment or even an operation under continued antithrombotic therapy should be considered.

The effect of antithrombotic therapy on the recurrence and outcome of chronic subdural hematoma after burr-hole craniostomy in a population-based cohort

PURPOSE

To study the effect of antithrombotic therapy (ATT) on the outcome of operatively treated chronic subdural hematomas (CSDH).

METHODS

A retrospective population-based cohort study from Eastern Finland including all adult patients who underwent a burr-hole craniostomy (BHC) for CSDH during 2016 and 2017. The follow-up time for recurrence was 6 months and for mortality 3 years.

RESULTS

A total of 301 CSDH patients were included in the study. ATT (antithrombotic therapy; antiplatelet or anticoagulant medication) was used by 164 patients (54.5%) at the time of diagnosis. The hematoma was bilateral in 102 patients (33.9%). Forty-seven patients (15.8%) encountered hematoma recurrence. Bilateral CSDHs required reoperations more often than unilateral hematomas (12.6% vs. 22.0%; p = 0.036) regardless of the primary operation (uni- or bilateral). A bivariate logistic regression analysis showed that bilateral hematoma (OR 1.918; 95% CI 1.013-3.630; p = 0.045) and male gender (OR 2.363; 95% CI 1.089-5.128; p = 0.030) independently predicted hematoma recurrence. The overall three-year mortality was 27.9%. The use of ATT was not associated with CSDH recurrence, and the length of the temporary postoperative ATT discontinuation did not correlate with the rate of thromboembolic events.

CONCLUSIONS

ATT did not affect CSDH recurrence in our study population, and the duration of the temporary postoperative ATT discontinuation was not associated with the rate of thromboembolic complications. Male gender and bilateral hematomas were more frequently associated with recurrences.

Hematoma subdural crónico: Una patología común de manejo complejo

Antecedentes:

El hematoma subdural crónico (HSDC) es una patología ampliamente estudiada, muy frecuente, sobre todo en adultos mayores; su cuadro clínico tiene una apariencia benigna y suele ir acompañado de múltiples comorbilidades asociadas a la edad, lo que resulta en un aumento de las complicaciones e incluso la muerte. Con el incremento de la expectativa de vida a nivel mundial, el uso de medicamentos antitrombóticos es cada vez más frecuente. El papel de estos fármacos en la evolución de la enfermedad como en la recurrencia, sigue siendo motivo de discusión.

Métodos:

Los autores revisaron la fisiopatología y características clínicas del HSDC. El presente artículo discute acerca de las terapéuticas actuales y las nuevas opciones de tratamiento que podrían mejorar los resultados. Este manuscrito es susceptible de cambios en el tiempo, con el desarrollo científico y tecnológico.

Resultados:

El HSDC puede ser abordado por vía quirúrgica y farmacológica; no obstante, un manejo individualizado requiere la consideracion cuidadosa de diversos factores. A pesar de los avances en el campo de la neurocirugía, la clásica trepanación craneal sigue siendo el Gold estándar en el HSDC y sobre todo en pacientes con síntomas graves. Se debe resaltar que aún hay aspectos de este procedimiento (como la localización del dren, número de drenajes, el efecto de la irrigación, la temperatura de la solución con que se irriga, etc.) que siguen siendo materia de estudio.

Conclusiones:

Entender el mecanismo de la enfermedad ha permitido explicar su historia natural y a su vez proponer nuevas alternativas de tratamiento. El manejo médico (atorvastatina, corticoides) ha generado gran interés por sus alentadores resultados preliminares. Recientemente, se ha reportado la terapia endovascular como una alternativa segura y existe gran expectativa por confirmar su efecto en estudios más grandes.

Impact of time to resumption of antithrombotic therapy on outcomes after surgical evacuation of chronic subdural hematoma: A multicenter cohort study

BACKGROUND

The decision to resume antithrombotic therapy after surgical evacuation of chronic subdural hematoma (CSDH) requires judicious weighing of the risk of bleeding against that of thromboembolism. This study aimed to investigate the impact of time to resumption of antithrombotic therapy on outcomes of patients after CSDH drainage.

METHODS

Data were obtained retrospectively from three tertiary hospitals in Singapore from 2010 to 2017. Outcome measures analyzed were CSDH recurrence and any thromboembolic events. Logistic and Cox regression tests were used to identify associations between time to resumption and outcomes.

RESULTS

A total of 621 patients underwent 761 CSDH surgeries. Preoperative antithrombotic therapy was used in 139 patients. 110 (79.1%) were on antiplatelets and 35 (25.2%) were on anticoagulants, with six patients (4.3%) being on both antiplatelet and anticoagulant therapy. Antithrombotic therapy was resumed in 84 patients (60.4%) after the surgery. Median time to resumption was 71 days (IQR 29 - 201). Recurrence requiring reoperation occurred in 15 patients (10.8%), of which 12 had recurrence before and three after resumption. Median time to recurrence was 35 days (IQR 27 - 47, range 4 - 82 days). Recurrence rates were similar between patients that were restarted on antithrombotic therapy before and after 14, 21, 28, 42, 56, 70 and 84 days, respectively. Thromboembolic events occurred in 12 patients (8.6%), of which five had the event prior to restarting antithrombosis.

CONCLUSIONS

Time to antithrombotic resumption did not significantly affect CSDH recurrence. Early resumption of antithrombotic therapy can be safe for patients with a high thromboembolic risk.

Mortality and Outcome in Patients Older Than 80 Years of Age Undergoing Burr-Hole Drainage of Chronic Subdural Hematoma

OBJECTIVE

Chronic subdural hematoma is frequently seen within the elderly population and neurosurgeons are confronted with patients older than 80 years presenting with symptomatic chronic subdural hematoma. However, data on surgical outcome are scarce. The aim of this study is to analyze the mortality and outcome after burr-hole drainage in patients older than 80 years.

METHODS

This is a single-center retrospective study including patients who underwent burr-hole drainage of chronic subdural hematoma between the years 2016 and 2019. The cohort was divided into 3 age groups (80-84 years; 85-89 years; >90 years). Primary outcome was 30-day and overall mortality, whereas secondary outcome measures were recurrence rates, postoperative bleeding rates, and outcome measured by the modified ranking scale. Uni- and multivariate analysis was conducted to assess for potential risk factors for mortality, recurrence and postoperative bleeding rates.

RESULTS

In total, 107 patients with a mean age of 85.5 ± 3.9 years were included. Mortality rate was less than 10% in each group, showing no significant difference between them (P = 0.455). No significant difference in recurrence and postoperative bleeding rates was seen (P = 0.491 and P = 0.532). Modified Ranking scale score differed significantly at release, whereas at follow-up no difference was seen. After uni- and multivariate analysis, age was not correlated with higher recurrence, postoperative bleeding, or mortality rates. Preoperative midline shift was found to be an independent risk factor for recurrence.

CONCLUSIONS

In patients older than 80 years undergoing burr-hole drainage for chronic subdural hematoma, age was not directly correlated with higher recurrence, postoperative bleeding, or mortality rates.

Low-Dose Acetylsalicylic Acid in Chronic Subdural Hematomas: A Neurosurgeon's Sword of Damocles

Background: The possible influence of different antithrombotic drugs on outcome after neurosurgical treatment of chronic subdural hematoma (CSDH) is still unclear. Nowadays, no randomized clinical trials are available. A metanalysis including 24 studies for a total of 1,812 pooled patients concluded that antiplatelets and anticoagulations present higher risk of recurrences. On the other hand, several studies highlighted that antithrombotic suspension, timing of surgery, and resumption of these drugs are still debated, and patients taking these present higher risk of thromboembolic events with no excess risk of bleed recurrences or worse functional outcome. Our assumption is that the real hemorrhagic risk related to antithrombotic drug continuation in CSDH may be overrated and the thromboembolic risk for discontinuation underestimated, especially in patients with high cardiovascular risk.

Methods: A comprehensive literature review with the search terms “acetylsalicylic acid” and “chronic subdural x” was performed. Clinical status, treatment, time of drug discontinuation, complications (in particular, rebleeding or thromboembolic events), and clinical and radiological outcome at follow-up were evaluated.

Results: Five retrospective studies were selected for the review, three of them reporting specifically low-dose acetylsalicylic intake and two of them general antithrombotic drugs for a total of 1,226 patients. Only two papers reported the thromboembolic rate after surgery; in one paper, it is not even divided from other cardiac complications.

Conclusion: The literature review does not clarify the best management of low-dose acetylsalicylic in CSDH patients, in particular, concerning the balance between thromboembolic event rates and rebleeding risks. We do believe that CSDH precipitates the worsening of comorbidities with a resulting increased mortality. Further studies clearly evaluating the thromboembolic events are strongly needed to clarify this topic.

In this perspective paper, we discuss the difficult choice of low-dose acetylsalicylic acid (LDAA) management in patients suffering from chronic subdural hematoma (CSDH). The balance between hemorrhagic and thromboembolic risks often represents a sword of Damocles for neurosurgeons, especially when dealing with patients with high cardiovascular risk. No guidelines are currently available, and a survey by Kamenova et al. showed that most neurosurgeons discontinue LDAA treatment for at least 7 days in the perioperative period of surgical evacuation of CSDH, even though recent studies show that early LDAA resumption might be safe. Thrombosis prophylaxis is administered by only 60%, even though patients with CSDH are at high risk of developing thromboembolic complications. We would like to bring attention to this controversial issue.

Chronic subdural hematoma-incidence, complications, and financial impact

OBJECTIVE

To examine the population-based incidence, complications, and total, direct hospital costs of chronic subdural hematoma (CSDH) treatment in a neurosurgical clinic during a 26-year period. The aim was also to estimate the necessity of planned postoperative follow-up computed tomography (CT).

METHODS

A retrospective cohort (1990-2015) of adult patients living in Pirkanmaa, Finland, with a CSDH was identified using ICD codes and verified by medical records (n = 1148, median age = 76 years, men = 65%). Data collection was performed from medical records. To estimate the total, direct hospital costs, all costs from hospital admission until the last neurosurgical follow-up visit were calculated. All patients were followed until death or the end of 2017. The annual number of inhabitants in the Pirkanmaa Region was obtained from the Statistics Finland (Helsinki, Finland).

RESULTS

The incidence of CSDH among the population 80 years or older has increased among both operatively (from 36.6 to 91/100,000/year) and non-operatively (from 4.7 to 36.9/100,000/year) treated cases. Eighty-five percent (n = 978) underwent surgery. Routine 4-6 weeks' postoperative follow-up CT increased the number of re-operations by 18% (n = 49). Most of the re-operations (92%) took place within 2 months from the primary operation. Patients undergoing re-operations suffered more often from seizures (10%, n = 28 vs 3.9%, n = 27; p < 0.001), empyema (4.3%, n = 12 vs 1.1%, n = 8; p = 0.002), and pneumonia (4.7%, n = 13 vs 1.4%, n = 12; p = 0.008) compared with patients with no recurrence. The treatment cost for recurrent CSDHs was 132% higher than the treatment cost of non-recurrent CSDHs, most likely because of longer hospital stay for re-admissions and more frequent outpatient follow-up with CT. The oldest group of patients, 80 years or older, was not more expensive than the others, nor did this group have more frequent complications, besides pneumonia.

CONCLUSIONS

Based on our population-based study, the number of CSDH patients has increased markedly during the study period (1990-2015). Reducing recurrences is crucial for reducing both complications and costs. Greater age was not associated with greater hospital costs related to CSDH. A 2-month follow-up period after CSDH seems sufficient for most, and CT controls are advocated only for symptomatic patients.

Predicting Chronic Subdural Hematoma Resolution and Time to Resolution Following Surgical Evacuation

Background: Growing evidence suggests that chronic subdural hematoma (CSDH) may have long-term adverse effects even after surgical evacuation. Hematoma recurrence is commonly reported as a short-term, postoperative outcome measure for CSDH, but other measures such as hematoma resolution may provide better insight regarding mechanisms behind longer-term sequelae. This study aims to characterize postoperative resolution times and identify predictors for this relatively unexplored metric. Methods: Consecutive cases (N = 122) of burr hole evacuation for CSDH by a single neurosurgeon at Columbia University Irving Medical Center from 2000 to 2019 were retrospectively identified. Patient characteristics, presenting factors, and date of hematoma resolution were abstracted from the electronic health record. Outcome measures included CSDH resolution at 6 months, surgery-to-resolution time, and inpatient mortality. Univariate and multivariate analyses were performed to determine predictors of outcome measures. Results: Hematoma resolution at 6 months was observed in 58 patients (47.5%), and median surgery-to-resolution time was 161 days (IQR: 85-367). Heavy drinking was predictive of non-resolution at 6 months and longer surgery-to-resolution time, while increased age was predictive of non-resolution at 6 months. Antiplatelet agent resumption was associated with non-resolution at 6 months and longer surgery-to-resolution time on univariate analysis but was not significant on multivariate analysis. Conclusion: Postoperative resolution times for most CSDHs are on the order of several months to a year, and delayed resolution is linked to heavy drinking and advanced age. Subsequent prospective studies are needed to directly assess the utility of hematoma resolution as a potential metric for long-term functional and cognitive outcomes of CSDH.

Influence of Antithrombotic Medication on the Risk of Chronic Subdural Hematoma Recurrence after Burr-Hole Surgery

OBJECTIVE

Chronic subdural hematoma (CSDH) is one of the most common intracranial hemorrhages. It can be managed with a simple surgical treatment such as burr-hole trephination and drainage. However, it has a relatively high recurrence rate. The mechanisms and risk factors for the recurrence have not yet been clearly identified and studies have reported varying results.

METHODS

We analyzed 230 patients with CSDH who were treated with burr-hole trephination and drainage at our institution from March 2011 to March 2016. The patients were divided into recurrence and non-recurrence groups and the medical records of each group were used to analyze the risk factors associated with CSDH recurrence.

RESULTS

After burr-hole trephination and drainage, CSDH recurrence was observed in 49 (21.3%) of the 230 patients. In univariate analysis, none of the factors showed statistical significance with respect to CSDH recurrence. In multivariate analysis, preoperative antithrombotic medication was the only independent risk factor for CSDH recurrence (odds ratio, 2.407; 95% confidence interval, 1.047-5.531).

CONCLUSION

The present study found that preoperative antithrombotic medication was independently associated with CSDH recurrence.

Impact of antithrombotic therapy on surgical treatment in patients with chronic subdural hematoma

OBJECTIVE

The effects of antithrombotic therapy on chronic subdural hematoma (CSDH) are controversial. Herein, we investigated the association of antithrombotic therapy with surgical complications and outcomes in patients with CSDH.

METHODS

We retrospectively analyzed 323 consecutive patients with CSDH who underwent single burr-hole craniostomy.

RESULTS

One hundred and eight patients (33%) underwent preoperative antithrombotic therapy. Hemorrhagic and thromboembolic complications were detected in 6 and 8 patients, respectively, which peaked at 3 and 4.5 days after CSDH surgery, respectively. CSDH recurrence was detected in 62 cases, and reoperation was required in 16 cases. Discontinuance of antiplatelet therapy for >2 weeks was significantly associated with thromboembolic complications (43%; p = 0.005). Postoperative use of multiple antithrombotic agents was significantly associated with CSDH recurrence (40%; p = 0.03). Further, earlier recurrence within 2 weeks was significantly associated with the following reoperation (62%; p = 0.006).

CONCLUSIONS

To reduce morbidity and minimize the risk of CSDH reoperation, the optimal timing for resumption of antithrombotic agents is approximately 3 days after CSDH surgery. Postoperative use of multiple antithrombotic agents can increase CSDH recurrence, while earlier recurrence may be a predictor for the following reoperation.

Reinitiation of Anticoagulation After Surgical Evacuation of Subdural Hematomas

BACKGROUND

Chronic subdural hematoma (cSDH) is an increasingly common condition due to the growing use of anticoagulation. Currently, there remains a lack of evidence to guide the optimal timing of anticoagulant reinitiation for stroke prevention in atrial fibrillation after cSDH evacuation. We aimed to better understand the perceived risks of hemorrhagic and embolic complications along with current practice patterns on restarting anticoagulation after surgical evacuation of cSDH.

METHODS

We conducted a survey of Canadian neurosurgeons and stroke neurologists using a novel self-administered questionnaire using clinical cases that included questions on clinical experience, practice setting, practice patterns, and perceptions on stroke/bleeding risk with anticoagulation reinitiation after cSDH evacuation. The instrument was evaluated for clinical sensibility by 5 neurosurgeons, neurologists, and intensivists.

RESULTS

The response rate after 4 mailings was 40% for neurosurgeons (55/136) and 21% for stroke neurologists (26/122). Almost all participants would restart anticoagulation for stroke prevention in atrial fibrillation after cSDH evacuation (91.8% in low-risk patients, 98.6% in high-risk patients). Time to reinitiation of anticoagulation varied considerably, particularly for high-risk patients where 36% of participants would restart anticoagulation within 1 week of surgery, 44% between 1 and 4 weeks after surgery, and 19% after 4 weeks postoperatively. The perceived risk of stroke and SDH reaccumulation varied considerably among participants and was dependent on timing of anticoagulation reinitiation.

CONCLUSIONS

There is considerable variation in current practice patterns and perceived risks of embolic and hemorrhagic complications with anticoagulation reinitiation after cSDH evacuation. These results demonstrate clinical equipoise that warrant further targeted investigation in large-scale randomized controlled trials.

Embolization of the Middle meningeal artery in chronic subdural hematoma - A systematic review

Chronic subdural hematomas (cSDH) are one of the most frequent reasons for consultation in neurosurgery. Multiple authors have proposed middle meningeal artery embolization (MMAE) as an option in cSDH patients to manage recurrence or avoid surgery altogether. Although many articles have been published on the matter, the current body of evidence still has to be evaluated before MMAE is integrated into clinical practice. The goal of this study was to review the evidence on MMAE in cSDH to assess its safety, feasibility, indications and efficacy. We performed a systematic review of the literature according to PRISMA guidelines using multiple electronic databases. Our search yielded a total of 18 original articles from which data were extracted. A total of 190 patients underwent MMAE from which 81.3% were symptomatic cSDH. Over half (52.3%) of the described population were undergoing antithrombotic therapy. Most (83%) procedures used polyvinyl alcohol (PVA) particles and no complications were reported regarding the embolization procedures. Although the definition of resolution varied among authors, cSDH resolution was reported in 96.8% of cases. MMAE is a feasible technique for cSDH, but the current body of evidence does not yet support its use as a standard treatment. Further studies with a higher level of evidence are necessary before MMAE can be formally recommended.