Middle Meningeal Artery Embolization in Recurrent Chronic Subdural Hematoma Combined with Arachnoid Cyst

Analysis of middle meningeal artery embolization for the treatment of chronic, acute on chronic, and subacute subdural hematomas

Background

Chronic subdural hematoma (cSDH) is a common sequela of traumatic brain injury. Middle meningeal artery embolization (MMAE) has shown promising results as an emerging minimally invasive alternative treatment. The purpose of this study is to examine the safety and efficacy of MMAE performed in patients with cSDH, acute-on-chronic, and subacute SDH with a traumatic etiology.

Methods

This retrospective study included cases performed at a Level II Trauma Center between January 2019 and December 2020 for MMAE of cSDHs. Data collected included patient demographic characteristics and comorbidities, SDH characteristics, complications, and efficacy outcomes. The lesion measurements were collected before the procedure, 4-6 weeks and 3-6 months post-procedure.

Results

In our patient population, 78% (39) either had lesions improve or completely resolved. The sample included 50 patients with a mean age of 74 years old. Statistically significant reductions in lesion size were found from pre- to post-procedure in the left lesions, right lesions, and midline shifts. The left lesions decreased from 13.88 ± 5.70 mm to 3.19 ± 4.89 mm at 3-6 months with P < 0.001. The right lesions decreased from 13.74 ± 5.28 mm to 4.93 ± 7.46 mm at 3-6 months with P = 0.02. Midline shifts decreased from 3.78 ± 3.98 mm to 0.48 ± 1.31 mm at 3-6 months with P = 0.02. No complications were experienced for bleeding, hematoma, worsening SDH, pseudoaneurysm, or stroke.

Conclusion

Our pilot study from a single center utilizing MMAE demonstrates that MMAE is successful without increasing treatment-related complications not only for cSDH but also in acute-on-cSDH and SDH with a subacute component.

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.

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.

The efficacy of postoperative middle meningeal artery embolization on chronic subdural hematoma - A multicentered randomized controlled trial

Background

Middle meningeal artery (MMA) embolization has recently emerged as a potential treatment for chronic subdural hematoma (cSDH). Numerous retrospective studies have suggested that it can potentially reduce the risk of hematoma recurrence following surgical evacuation. We have conducted a randomized controlled trial to investigate the effectiveness of postoperative MMA embolization in reducing recurrence rate, residual hematoma thickness as well as improving functional outcome.

Methods

Patients aged 18 or above were recruited. Following evacuation through burr hole or craniotomy, patients were randomly allocated to undergo either MMA embolization or standard care (monitoring). The primary outcome was symptomatic recurrence requiring redo evacuation. Secondary outcomes include residual hematoma thickness and modified Rankin Scale (mRS) at 6 weeks and 3 months.

Results

Thirty-six patients (41 cSDHs) were recruited between April 2021 and September 2022. Seventeen patients (19 cSDHs) were allocated to the embolization group and 19 patients (22 cSDHs) were in the control group. No symptomatic recurrence was observed in the treatment group while 3 control patients (15.8%) underwent repeat surgery for symptomatic recurrence, however, it was not statistically significant (P = 0.234). Furthermore, there was no significant difference in residual hematoma thickness at 6 weeks or 3 months between the two groups. All patients in the embolization group had a good functional outcome (mRS 0-1) at 3 months, which was significantly higher than the 53% observed in the control group. No complications related to MMA embolization were reported.

Conclusion

Further study with larger sample size is required to evaluate the efficacy of MMA embolization.

Long-Term Middle Meningeal Artery Caliber Reduction Following Trisacryl Gelatine Microsphere Embolization for the Treatment of Chronic Subdural Hematoma

PURPOSE

Middle meningeal artery (MMA) particle embolization is a promising treatment of chronic subdural hematomas (CSDH). The main purpose of this study is to measure MMA proximal caliber and assess the visibility of the two main MMA branches as a surrogate for long-term distal arterial patency following MMA CSDH embolization with trisacryl gelatine microspheres (TAGM).

METHODS

This is a single-center retrospective study. All patients having undergone MMA TAGM only embolization for CSDH treatment between 15 March 2018 and 6 June 2020 with an interpretable follow-up magnetic resonance imaging (MRI) examination and no confounding factors were included. Patients were compared with controls matched for age, sex and MRI machine. Two independent readers analyzed the MRI images.

RESULTS

In this study, 30 patients having undergone embolization procedures using TAGM of 36 MMAs were included. The follow-up MRI scans were performed after a mean delay of 14.8 ± 7.1 months (range 4.9-29.4 months). The mean diameter of TAGM embolized MMAs (1 mm; 95% confidence interval, CI 0.9-1.1) was significantly smaller than the mean diameter of paired control MMAs (1.3 mm; 95% CI 1.3-1.4) (p < 0.001). The mean proximal diameter of the embolized MMAs (0.9 mm; 95% CI 0.7-1.1) was significantly smaller than the mean diameter of the contralateral MMAs in the same patients (1.4 mm; 95% CI 1.3-1.6)(p < 0.001).

CONCLUSION

Long-term follow-up MRI demonstrated a significant impact of TAGM embolization on MMA proximal caliber as well as on the visibility of the two main MMA branches. All comparisons indicated that there was a probable lasting impact of embolization on the patency of distal branches.

Embolization as adjunctive treatment to achieve complete cure of ruptured arachnoid cyst associated with chronic subdural hematoma

INTRODUCTION

Chronic Subdural Hematoma (CSDH) is a rare but classical evolutive complication of arachnoid cysts (AC). Its management has rarely been evaluated to date. Several approaches have been proposed including conservative and surgical treatments. Endovascular treatment in such CSDH subtype remains poorly reported.

CASE PRESENTATION

We present here an original case of a 16 years-old-boy suffering from ruptured AC responsible for CSDH successfully treated with embolization.

CONCLUSION

Endovascular approach may be considered in the treatment of CSDH related to arachnoid cyst rupture.

Middle Meningeal Artery Embolization for Primary Treatment of a Chronic Subdural Hematoma in a Pediatric Patient: A Systematic Review of the Literature and Case Report

BACKGROUND

Middle meningeal artery (MMA) embolization is becoming increasingly studied as a safe, effective treatment for chronic subdural hematoma (cSDH) in adults. Among pediatric patients, however, MMA embolization for cSDH has been rarely described, and the potential benefit of this approach for pediatric patients remains unknown.

OBJECTIVE

To systematically review the literature and identify cases of pediatric MMA embolization for cSDH. We also report our experience with pediatric MMA embolization.

METHODS

A systematic review of the literature was performed to identify cases of pediatric MMA embolization for cSDH. Inclusion criteria included English language availability and pediatric age defined as less than 18 years. A pediatric patient treated with MMA embolization was also identified at our institution.

RESULTS

Five cases of pediatric MMA embolization for cSDH were identified in the literature. Two were associated with arachnoid cysts, 2 with antiplatelet/anticoagulation therapy, and 1 with abusive head trauma. There were no adverse events, and all patients demonstrated clinical and radiological improvement on follow-up. At our institution, a previously healthy 8-year-old male was found to have a right-sided acute-on-chronic SDH during a headache evaluation. A diagnostic angiogram was performed to rule out a dural arteriovenous fistula, and right-sided MMA embolization was performed concurrently. Rapid clinical and radiological improvement was observed, with complete resolution by 6 months.

CONCLUSION

MMA embolization may represent a treatment option for pediatric patients with cSDH.

[Middle meningeal artery embolization for chronic subdural haematoma. Case series and literature review]

Middle meningeal artery embolization as primary method for treatment of chronic subdural hematomas became more popular in past decade. There are few large case series (>150 patients) and literature reviews characterizing advantages and drawbacks of endovascular treatment and technical features of surgeries. In this manuscript, the authors report 11 patients with chronic subdural hematoma scheduled for middle meningeal artery embolization and review the literature data on this issue.

Endovascular Treatment of Chronic Subdural Hematomas through Embolization: A Pilot Study with a Non-Adhesive Liquid Embolic Agent of Minimal Viscosity (Squid)

OBJECTIVE

Endovascular embolization using non-adhesive agents (e.g., ethylene vinyl alcohol copolymer with suspended micronized tantalum dissolved in dimethyl sulfoxide; Squid, Balt Extrusion) is an established treatment of brain arteriovenous malformations, dural arteriovenous fistulas, and hypervascular neoplasms. Middle meningeal artery (MMA) embolization is a relatively new concept for treating chronic subdural hematomas (CSDH). This study aimed to evaluate the safety and effectiveness of the use of Squid in the endovascular treatment of CSDH.

METHODS

Embolization was offered to patients with CSDH with minimal or moderate neurological deficits and patients who had previously undergone open surgery to evacuate their CSDH without a significant effect. Distal catheterization of the MMA was followed by embolization of the hematoma capsule with Squid 12 or Squid 18. Safety endpoints were ischemic or hemorrhagic stroke and any other adverse event of the endovascular procedure. Efficacy endpoints were the feasibility of the intended procedure and a ≥ 50% reduction of the maximum depth of the CSDH confirmed by follow-up computed tomography (CT) after >3 months.

RESULTS

Between November 2019 and July 2021, 10 patients (3 female and 7 male, age range 42-89 years) were enrolled. Five patients had bilateral hematomas, and five patients had previously been operated on with no significant effect and recurrent hematoma formation. The attempted embolization was technically possible in all patients. No technical or clinical complication was encountered. During a post-procedural follow-up (median 90 days), 10 patients improved clinically. A complete resolution of the CSDH was observed in 10 patients. The clinical condition of all enrolled patients during the so-far last contact was rated mRS 0 or 1.

CONCLUSION

A distal catheterization of the MMA for the endovascular embolization of CSDH with Squid allowed for the devascularization of the MMA and the dependent vessels of the hematoma capsule. This procedure resulted in a partial or complete resolution of the CSDH. Procedural complications were not encountered.

Efficacy and mid-term outcome of middle meningeal artery embolization with or without burr hole evacuation for chronic subdural hematoma compared with burr hole evacuation alone

BACKGROUND

Chronic subdural hematoma (CSDH) is a common neurosurgical condition with high recurrence rates. Repeated microbleedings from fragile neo-vessels supplied by peripheral branches of the middle meningeal artery (MMA) are believed to be responsible for the growth and recurrence of CSDH. Thus, MMA embolization might be a promising method to prevent re-bleedings and recurrences. This study aims to assess the efficacy, complication rates, and mid-term outcome of MMA embolization with or without burr hole irrigation compared with burr hole irrigation alone.

METHODS

Patients diagnosed with CSDH who underwent MMA embolization and/or surgical treatment were retrospectively recruited to this single-center study. The outcome variables were defined as treatment-related complications, clinical outcome at discharge, rate of revision surgery, and CT findings during the follow-up period.

RESULTS

A total of 132 patients with CSDH were included in the study. The use of antiplatelet/anticoagulant medication was significantly higher in the combined treatment and embolization group (p<0.001). A trend towards fewer revision surgeries was found in the group of patients who received MMA embolization combined with burr hole irrigation (p=0.083). Follow-up was available for 73 patients (55.3%) with a mean follow-up period of 3.4±2.2 months. Eight patients (15.1%) of the surgery group showed hematoma re-accumulation and needed surgical rescue, whereas only one patient (5.0%) of the combined treatment group needed revision surgery. In all patients treated with only MMA embolization, complete hematoma resolution was found.

CONCLUSION

MMA embolization is a safe and efficacious minimal invasive adjuvant and/or alternative procedure for the treatment of CSDH with a reduced recurrence rate.

Surgical occlusion of middle meningeal artery in treatment of chronic subdural haematoma: anatomical and technical considerations

BACKGROUND

The primary aim of chronic subdural haematoma (CSDH) treatment is to relieve pressure to improve neurological symptoms. The secondary aim is to avoid recurrence. The blood supply from the middle meningeal artery (MMA) to the haematoma membranes has recently become a research target, to enhance our understanding of the processes leading to growth and re-growth of a CSDH. Several studies indicate that endovascular embolization of the MMA (eMMA) reduces recurrence rates, but this effect must be confirmed in a randomized controlled setting. Endovascular embolization is an advanced and costly procedure carrying a significant risk of embolism in the elderly. The aim of this study was to assess anatomical and technical aspects of surgical occlusion of the MMA (soMMA) via a single same-procedure burr hole, as an alternative to eMMA.

METHOD

Technical aspects of soMMA were assessed using cadaver head dissection. MMA anatomy was examined by mapping the branching pattern and distribution of MMA in dry skulls, and CSDH position was investigated by analysis of computed tomography (CT) of CSDHs. Finally, we evaluated the possibility of CT-guided navigation to mark the branching point of the anterior MMA division on the skin.

RESULTS

We established anatomical landmarks to locate the MMA and found that particularly the anterior MMA branch can be occluded through a single burr hole at the pterion during the same procedure as haematoma decompression. CT of 1454 CSDHs in 1162 patients showed that the CSDH was anteriorly located in 57.5% compared with posteriorly in only 3%. This correlated with the anterior branch of the MMA being dominant in 58% of dry skull samples examined. We further confirmed that the MMA can be localized by neuronavigation as an alternative to using anatomical landmarks and average measurements.

CONCLUSION

A CSDH is mainly anteriorly located and supposedly primarily supplied by the anterior MMA branch. In a simulated setting, soMMA can be performed during the same procedure as haematoma decompression. A few reservations notwithstanding, we find that soMMA may be a viable alternative to eMMA in most CSDH cases and that soMMA should be further evaluated in a clinical setting.

A propensity-adjusted comparison of middle meningeal artery embolization versus conventional therapy for chronic subdural hematomas

OBJECTIVE

Middle meningeal artery (MMA) embolization is a promising treatment strategy for chronic subdural hematomas (cSDHs). However, studies comparing MMA embolization and conventional therapy (surgical intervention and conservative management) are limited. The authors aimed to compare MMA embolization versus conventional therapy for cSDHs using a propensity-adjusted analysis.

METHODS

A retrospective study of all patients with cSDH who presented to a large tertiary center over a 2-year period was performed. MMA embolization was compared with surgical intervention and conservative management. Neurological outcome was assessed using the modified Rankin Scale (mRS). A propensity-adjusted analysis compared MMA embolization versus surgery and conservative management for all individual cSDHs. Primary outcomes included change in hematoma diameter, treatment failure, and complete resolution at last follow-up.

RESULTS

A total of 231 patients with cSDH met the inclusion criteria. Of these, 35 (15%) were treated using MMA embolization, and 196 (85%) were treated with conventional treatment. On the latest follow-up, there were no statistically significant differences between groups in the percentage of patients with worsening mRS scores. Of the 323 total cSDHs found in 231 patients, 41 (13%) were treated with MMA embolization, 159 (49%) were treated conservatively, and 123 (38%) were treated with surgical evacuation. After propensity adjustment, both surgery (OR 12, 95% CI 1.5-90; p = 0.02) and conservative therapy (OR 13, 95% CI 1.7-99; p = 0.01) were predictors of treatment failure and incomplete resolution on follow-up imaging (OR 6.1, 95% CI 2.8-13; p < 0.001 and OR 5.4, 95% CI 2.5-12; p < 0.001, respectively) when compared with MMA embolization. Additionally, MMA embolization was associated with a significant decrease in cSDH diameter on follow-up relative to conservative management (mean -8.3 mm, 95% CI -10.4 to -6.3 mm, p < 0.001).

CONCLUSIONS

This propensity-adjusted analysis suggests that MMA embolization for cSDH is associated with a greater extent of hematoma volume reduction with fewer treatment failures than conventional therapy.

CTA-Based Patient-Tailored Femoral or Radial Frontline Access Reduces the Rate of Catheterization Failure in Chronic Subdural Hematoma Embolization

BACKGROUND AND PURPOSE

Chronic subdural hematoma embolization, an apparently simple procedure, can prove to be challenging because of the advanced age of the target population. The aim of this study was to compare 2 arterial-access strategies, femoral versus patient-tailored CTA-based frontline access selection, in chronic subdural hematoma embolization procedures.

MATERIALS AND METHODS

This was a monocentric retrospective study. From the March 15, 2018, to the February 14, 2019 (period 1), frontline femoral access was used. Between February 15, 2019, and March 30, 2020 (period 2), the choice of the frontline access, femoral or radial, was based on the CTA recommended as part of the preoperative work-up during both above-mentioned periods. The primary end point was the rate of catheterization failure. The secondary end points were the rate of access site conversion and fluoroscopy duration.

RESULTS

During the study period, 124 patients (with 143 chronic subdural hematomas) underwent an embolization procedure (mean age, 74 [SD, 13] years). Forty-eight chronic subdural hematomas (43 patients) were included during period 1 and were compared with 95 chronic subdural hematomas (81 patients) during period 2. During the first period, 5/48 (10%) chronic subdural hematoma embolizations were aborted due to failed catheterization, significantly more than during period 2 (1/95, 1%; P = .009). The rates of femoral-to-radial (P = .55) and total conversion (P = .86) did not differ between the 2 periods. No significant difference was found regarding the duration of fluoroscopy (P = .62).

CONCLUSIONS

A CTA-based patient-tailored choice of frontline arterial access reduces the rate of catheterization failure in chronic subdural hematoma embolization procedures.

Spontaneous rupture of middle fossa arachnoid cysts: surgical series from a single center pediatric hospital and literature review

PURPOSE

Arachnoid cysts may present with symptoms deriving from cyst rupture, usually causing intracystic hemorrhage and subdural hematoma or hygroma. Rupture is usually caused by minor trauma, spontaneous rupture is an exceptional event, and 57 cases have been described in literature. We here present and discuss the largest series of spontaneously ruptured middle fossa arachnoid cysts in order to investigate clinical presentation and best treatment available.

METHODS

We report a retrospective series of 17 pediatric patients surgically treated for middle fossa arachnoid cyst with signs of cyst rupture without a history of trauma in the previous 90 days. We describe clinical presentation, treatment, and outcome at follow-up discussing our results with a literature review including all reported cases of spontaneous rupture of middle fossa arachnoid cysts.

RESULTS

In our experience patients most frequently presented with subdural hygroma, in literature, a chronic hematoma was most frequently reported. Headache is the most reported symptom at presentation. Neurological deficits and consciousness alterations are rare. Surgical treatment may resolve brain compression only or reduce rupture recurrence risk. Conservative treatment has also been proposed. Different treatments are reported and discussed focusing on indications, contraindications, risks, and expected benefits.

CONCLUSION

We propose, when safely possible, microsurgical cyst fenestration in skull base cisterns as the treatment of choice for these patients as long as it addresses both immediate decompression and risk of rupture recurrence. We report good outcomes and low incidence of complications from our series with a mean postoperative follow-up of 30 months.

Middle Meningeal Artery Embolization for Chronic Subdural Hematoma

Chronic subdural hematoma (cSDH) is a common disease process associated with significant morbidity that occurs most often in elderly patients. Asymptomatic patients are typically treated conservatively, with surgical intervention reserved for patients with symptomatic and/or large hematomas that cause brain compression. However, conservatively managed cSDH cases frequently progress, and surgical evacuation of cSDH is associated with high rates of complication and recurrence. Recently, successful treatment of cSDH via middle meningeal artery (MMA) embolization has been reported in small case series and case reports. This article reviews the existing literature on MMA embolization for cSDH and discusses the need for randomized control trials and/or large prospective studies to establish the efficacy of MMA embolization for this disease.

Middle meningeal artery embolization for chronic subdural hematoma: an institutional technical analysis

BACKGROUND

Recently, middle meningeal artery (MMA) embolization has emerged as a potentially safe and effective method of treating chronic subdural hematoma (cSDH).

OBJECTIVE

To report a single-center experience with MMA embolization and examines the type of embolic material used, the extent of penetration, and the number of MMA branches embolized.

METHODS

A retrospective analysis of all patients with MMA embolization from 2018 through 2019 was performed. A failed outcome was defined as either surgical rescue and/or greater than 10 mm of hematoma residual or reaccumulation following embolization.

RESULTS

Of 35 patients, surgery had failed for 9 (26%) and initial conservative treatment had failed for 6 (17%). Of 41 MMA embolizations, including those in six patients with bilateral cSDH who underwent bilateral MMA embolization, 29 (72%) were performed using ethylene vinyl alcohol copolymer (Onyx), 7 (17%) using particles, and 5 (12%) using n-butyl cyanoacrylate. Both the anterior and posterior MMA divisions were embolized in 29 cases (71%); distal penetration of these branches was achieved in 25 embolizations (61%). Twenty-six (63%) cSDHs completely resolved. Complete resolution was seen in 22 of 29 hematomas (76%) in which both anterior and posterior MMA branches were occluded versus 4 of 12 (33%) following single-branch embolization (p=0.014). Embolization of one cSDH (2%) failed.

CONCLUSION

MMA embolization of cSDHs appears to be both safe and efficacious. Furthermore, embolization of both the anterior and posterior MMA branches may be associated with increased odds of complete resolution.

Middle meningeal artery embolization to treat progressive epidural hematoma: a case report

Progressive epidural hematoma is a form of acute epidural hematoma that gradually expands from a small initial hematoma; in cases that are clinically aggravated due to the presence of a mental illness or neurological condition, patients should be surgically treated for evacuation of the hematoma, but poorer outcomes are expected if the patient has several medical co-morbidities for surgery. We experienced two cases of progressive epidural hematoma which were successfully managed by endovascular treatment: an 85-year-old male with medical co-morbidities and a 51-year-old female with a poor-grade subarachnoid hemorrhage resulting from the rupture of a dissecting aneurysm of the vertebral artery. In both cases, a middle meningeal artery embolization was performed and contrast leakage was observed and controlled using cerebral angiography, halting the progression of their epidural hematomas. Thus, endovascular embolization of a middle meningeal artery may play a useful role in salvage therapy in certain complicated situations that limit treatment of the hematoma by surgical evacuation.

Middle meningeal artery embolization reduces the post-operative recurrence rate of at-risk chronic subdural hematoma

BACKGROUND

Embolization of the middle meningeal artery (MMA) has emerged as a potential treatment of chronic subdural hematomas (CSDHs).

OBJECTIVE

To evaluate the impact on recurrence rate of postsurgical embolization of CSDH in patients with a higher than average risk of recurrence.

METHODS

A monocentric retrospective study was performed on retrospectively collected data. From March 2018 to December 2019, embolization of the MMA was proposed as an adjunct postoperative treatment after burr-hole surgery in patients operated for a recurrent CSDH or a CSDH with an independent recurrence risk factor, including antiplatelet therapy, full anticoagulation therapy, coagulation disorder, hepatopathy, or chronic alcoholism. Patients who had undergone postoperative embolization were compared with a historic group of patients operated between March 2016 and March 2018, selected based on the same inclusion criteria.

RESULTS

During the study period, 89 patients (with 74 unilateral and 15 bilateral CSDHs) were included and underwent an embolization procedure, leading to 91 out of a total of 104 MMA being embolized (88%). These were compared with 174 patients (138 unilateral and 36 bilateral CSDH) in the historic control group. One major procedure-related adverse event was registered. Four of the 89 patients (4%) required surgery for a CSDH recurrence in the embolization group, significantly less than the 24 of 174 patients (14%) in the control group (OR=0.28, 95% CI 0.07 to 0.86, p=0.02).

CONCLUSIONS

Postsurgical embolization of the MMA may reduce the recurrence rate of CSDHs with a risk factor of recurrence.

Embolization of the middle meningeal artery in patients with chronic subdural hematoma-a systematic review and meta-analysis

BACKGROUND

Chronic subdural hematoma (CSDH) remains a neurosurgical condition with high recurrence rate after surgical treatment. The primary pathological mechanism is considered to be repeated microbleedings from fragile neo-vessels within the outer hematoma membrane. The neo-vessels are supplied from peripheral branches of the middle meningeal artery, and embolization of MMA (eMMA) has been performed to prevent re-bleeding episodes and thereby CSDH recurrence.

OBJECTIVE

To evaluate the published evidence for the effect of eMMA in patients with recurrent CSDH. Secondarily, to investigate the effect of eMMA as an alternative to surgery for primary treatment of CSDH.

METHOD

A systematic review of the literature on eMMA in patients with recurrent CSDH was conducted. PubMed, Embase, and Cochrane databases were reviewed using the search terms: Embolization, Medial Meningeal Artery, Chronic Subdural Haematoma, and Recurrence. Furthermore, the following mesh terms were used: Chronic Subdural Haematoma AND embolization AND medial meningeal artery AND recurrence. Eighteen papers were found and included. No papers were excluded. The number of patients with primary CSDH and the number of patients with recurrent CSDH treated with eMMA were listed. Furthermore, the number of recurrences in both categories was registered.

RESULTS

Eighteen papers with a total of 191 included patients diagnosed with CSDH treated with eMMA for primary and recurrent CSDH were identified. Recurrence rate for patients treated with eMMA for recurrent CSDH was found to be 2.4%, 95% CI (0.5%; 11.0%), whereas the recurrence rate for patients treated with eMMA for primary CSDH was 4.1%, 95% CI (1.4%; 11.4%).

CONCLUSION

eMMA is a minimally invasive procedure for treatment of CSDH. Although this study is limited by publication bias, it seems that this procedure may reduce recurrence rates compared with burr hole craniostomy for both primary and recurrent hematomas. A controlled study is warranted.

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.

Safety and Effectiveness of Embolization for Chronic Subdural Hematoma: Systematic Review and Case Series

INTRODUCTION

Embolization of the middle meningeal artery (MMA) has emerged as a minimally invasive means of managing subdural hematoma. The purpose of this study was to systematically review the literature on the safety and effectiveness of this treatment and to share our clinical experience.

METHODS

This review was registered with PROSPERO. PubMed, CINAHL, EMBASE, and the Cochrane Library were searched using MeSH (Medical Subject Headings) terms for MMA embolization and chronic subdural hematoma (CSDH) from January 2000 to November 2018. All articles in the English language literature describing MMA embolization for CSDH were included, irrespective of study design. Consecutive patients who underwent MMA embolization at our hospital between January 2017 and June 2018 comprised our clinical experience.

RESULTS

Fifteen studies with 193 procedures were included in the review. Ninety-five cases (49.2%) involved primary MMA embolization; 88 embolizations (45.6%) for recurrent CSDH and 10 (5.2%) for prophylaxis after surgical evacuation were performed. Recurrence after MMA embolization requiring further treatment occurred in 7 cases (3.6%). All other patients had symptomatic relief with no further recurrence. No procedure-related complications were reported. Polyvinyl alcohol was the most commonly used material. Our series included 8 patients treated with Onyx. All had symptom relief and significant reduction in hematoma size; no recurrences or procedure-related complications were observed.

CONCLUSIONS

MMA embolization of CSDH is safe and effective for CSDH treatment based on a documented recurrence rate of 3.6% and lack of reported complications.

Middle meningeal artery embolization for the management of chronic subdural hematoma

Chronic subdural hematoma (cSDH) is one of the most common neurosurgical diagnoses in adults. The disease is fundamentally a disorder of the meningeal blood vessels, and options exist for the minimally invasive neuroendovascular management. We review the potential role for the endovascular management of cSDH within the context of a discussion of the epidemiology, pathophysiology, and conventional management of this disease.

Trifurcated external carotid artery and complete gamma-loop of its maxillary branch

The external carotid artery (ECA) normally bifurcates terminally with the superficial temporal artery (STA) and the maxillary artery (MA). From the horizontally coursing, mandibular segment of the MA leaves the middle meningeal artery (MMA). We hereby report a previously unknown anatomic possibility, incidentally found during an angio-CT scan in an adult female patient. Unilaterally, the ECA was terminally trifurcated, sending off the MA, STA, and MMA. On that side, the mandibular segment of the MA had a gamma-loop and the contralateral one had a U-loop; both these loops were inferior to the lateral pterygoid muscle, closely approaching the respective lingula of the mandible. These findings are relevant during surgery of the parotid gland and infratemporal fossa, approaches of the MMA, and inferior alveolar nerve blocks. The modified origin of the MMA could be explained by an altered development of the primitive stapedial artery.

Middle Meningeal Artery Embolization for Chronic Subdural Hematoma: A Series of 60 Cases

BACKGROUND

Chronic subdural hematoma (SDH) is a particularly challenging pathology due to high recurrence rates (2%-37%) and complex medical comorbidities that tend to afflict the patient population. Recently, there have been several case series published describing the use of middle meningeal artery (MMA) embolization as an alternative to surgery for treatment of new or recurrent chronic SDH.

OBJECTIVE

To describe our first 60 cases of MMA embolization for chronic SDH.

METHODS

MMA embolization was performed using angiography, selective microcatheterization of the MMA, and infusion of polyvinyl alcohol particles. Outcomes were assessed clinically and with interval imaging studies at 1 d, 2 wk, and 6 wk postprocedure, and additional intervals as indicated.

RESULTS

MMA embolization was performed successfully on 60 total SDHs in 49 patients. This includes upfront treatment for new (not previously treated) SDH in 42, for recurrence in 8, and prophylaxis (soon after surgical evacuation) in 10. There were 3 mortalities (unrelated to the procedure), and no procedural complications. Of the 50 nonprophylactic cases, there were 4 (8.9%) cases of recurrence requiring surgical evacuation, and 31 (68.9%) that had resolution or reduction in size >50% of SDH at longest follow-up. Overall, 41 (91.1%) were stable or decreased in size and able to avoid surgery.

CONCLUSION

MMA embolization may represent a minimally-invasive alternative to surgery for new or recurrent chronic SDH, or as prophylaxis to reduce the risk of recurrence after surgery. Given our encouraging results with a 91% long-term success rate, a large scale clinical trial is warranted.

Middle Meningeal Artery Embolization for Chronic Subdural Hematoma

Purpose To evaluate the effect of middle meningeal artery (MMA) embolization on chronic subdural hematoma (CSDH) and compare the treatment outcomes of MMA embolization and conventional treatment. Materials and Methods All consecutive patients 20 years or older with CSDH were assessed for eligibility. CSDHs with a focal location, a thickness of 10 mm or less, no mass effect, or underlying conditions were excluded. Seventy-two prospectively enrolled patients with CSDH underwent MMA embolization (embolization group; as the sole treatment in 27 [37.5%] asymptomatic patients and with additional hematoma removal for symptom relief in 45 [62.5%] symptomatic patients). For comparison, 469 patients who underwent conventional treatment were included as a historical control group (conventional treatment group; close, nonsurgical follow-up in 67 [14.3%] and hematoma removal in 402 [85.7%] patients). Primary outcome was treatment failure defined as a composite of incomplete hematoma resolution (remaining or reaccumulated hematoma with thickness > 10 mm) or surgical rescue (hematoma removal for relief of symptoms that developed with continuous growth of initial or reaccumulated hematoma). Secondary outcomes included surgical rescue as a component of the primary outcome and treatment-related complication for safety measure. Six-month outcomes were compared between the study groups with logistic regression analysis. Results Spontaneous hematoma resolution was achieved in all of 27 asymptomatic patients undergoing embolization without direct hematoma removal. Hematoma reaccumulation occurred in one (2.2%) of 45 symptomatic patients receiving embolization with additional hematoma removal. Treatment failure rate in the embolization group was lower than in the conventional treatment group (one of 72 patients [1.4%] vs 129 of 469 patients [27.5%], respectively; adjusted odds ratio [OR], 0.056; 95% confidence interval [CI]: 0.011, 0.286; P = .001). Surgical rescue was less frequent in the embolization group (one of 72 patients [1.4%] vs 88 of 469 patients [18.8%]; adjusted OR, 0.094; 95% CI: 0.018, 0.488; P = .005). Treatment-related complication rate was not different between the two groups (0 of 72 patients vs 20 of 469 patients [4.3%]; adjusted OR, 0.145; 95% CI: 0.009, 2.469; P = .182). Conclusion MMA embolization has a positive therapeutic effect on CSDH and is more effective than conventional treatment. ^© RSNA, 2017.

Clinical importance of the middle meningeal artery: A review of the literature

The middle meningeal artery (MMA) is a very important artery in neurosurgery. Many diseases, including dural arteriovenous fistula (DAVF), pseudoaneurysm, true aneurysm, traumatic arteriovenous fistula (AVF), moyamoya disease (MMD), recurrent chronic subdural hematoma (CSDH), migraine and meningioma, can involve the MMA. In these diseases, the lesions occur in either the MMA itself and treatment is necessary, or the MMA is used as the pathway to treat the lesions; therefore, the MMA is very important to the development and treatment of a variety of neurosurgical diseases. However, no systematic review describing the importance of MMA has been published. In this study, we used the PUBMED database to perform a review of the literature on the MMA to increase our understanding of its role in neurosurgery. After performing this review, we found that the MMA was commonly used to access DAVFs and meningiomas. Pseudoaneurysms and true aneurysms in the MMA can be effectively treated via endovascular or surgical removal. In MMD, the MMA plays a very important role in the development of collateral circulation and indirect revascularization. For recurrent CDSHs, after burr hole irrigation and drainage have failed, MMA embolization may be attempted. The MMA can also contribute to the occurrence and treatment of migraines. Because the ophthalmic artery can ectopically originate from the MMA, caution must be taken to avoid causing damage to the MMA during operations.