Middle Meningeal Artery Embolization as Treatment for Chronic Subdural Hematoma: A Case Series

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.

Impact of Embolisate Penetration, Type, and Technique on Results After Standalone Middle Meningeal Artery Embolization for Chronic Subdural Hematoma

BACKGROUND AND OBJECTIVES

Middle meningeal artery embolization (MMAE) has emerged as a promising modality for chronic/subacute subdural hematoma treatment; however, consensus regarding embolization technique and embolisate has not been achieved. We thus sought to compare the efficacy of distinct MMAE techniques and embolisate.

METHODS

An institutional registry was reviewed to identify patients undergoing standalone MMAE for symptomatic chronic/subacute subdural hematoma. Surgical rescue rate and time preceding 50% hematoma resolution were evaluated across 3 technical groups: aggressive penetration (AP), nonaggressive penetration with proximal coil embolization (NP-PC), and nonaggressive penetration alone (NP). Effect sizes were adjusted for demographic, neurological and radiological features through multivariable logistic and Cox regression.

RESULTS

Among 117 procedures, 33.3% achieved AP, 36.8% had NP-PC, and 29.9% had NP. The rate of surgical rescue was 2.6% after AP, 9.3% for NP-PC, and 11.4% for NP. In patients not undergoing rescue surgery, 82.4% achieved hematoma resolution ≥50% at a median imaging follow-up of 56 days; AP or NP-PC were each statistically significantly associated with enhanced hematoma resolution as compared with NP (P = .02). Similarly, sensitivity analysis within medium-size hematoma and antiplatelet/anticoagulation-at-admission subgroups revealed a superiority of resolution after AP or NP-PC. A unique, comparative secondary analysis of liquid embolisate (Onyx vs n-butyl cyanoacrylate) revealed no impact on rate of surgical rescue or hematoma resolution.

CONCLUSION

AP was associated with the lowest rate of surgical rescue, while both AP and NP-PC were associated with improved rates of hematoma resolution.

Middle meningeal artery embolization associated with reduced chronic subdural hematoma volume and midline shift in the acute postoperative period

BACKGROUND

Middle meningeal artery (MMA) embolization for endovascular treatment of chronic subdural hematoma (cSDH) is growing in popularity. cSDH volume and midline shift were analyzed in the immediate postoperative window after MMA embolization.

METHODS

A retrospective analysis of cSDHs managed via MMA embolization from January 1, 2018 to March 30, 2021 was performed at a large quaternary center. Pre- and postoperative cSDH volume and midline shift were quantified with CT. Postoperative CT was obtained 12 to 36 hours after embolization. Paired t-tests were used to determine significant reduction. Multivariate analysis was performed using logistic and linear regression for percent improvement from baseline volume.

RESULTS

In total, 80 patients underwent MMA embolization for 98 cSDHs during the study period. The mean (SD) initial cSDH volume was 66.54 (34.67) mL, and the mean midline shift was 3.79 (2.85) mm. There were significant reductions in mean cSDH volume (12.1 mL, 95% CI 9.32 to 14.27 mL, P<0.001) and midline shift (0.80 mm, 95% CI 0.24 to 1.36 mm, P<0.001). In the immediate postoperative period, 22% (14/65) of patients had a>30% reduction in cSDH volume. A multivariate analysis of 36 patients found that preoperative antiplatelet and anticoagulation use was significantly associated with an expansion in volume (OR 0.028, 95% CI 0.000 to 0.405, P=0.03).

CONCLUSION

MMA embolization is safe and effective for the management of cSDH and is associated with significant reductions in hematoma volume and midline shift in the immediate postoperative period.

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

BACKGROUND

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

MATERIAL AND METHODS

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

RESULTS

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

CONCLUSION

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

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.

Radiological evaluation of middle meningeal artery by 3D rotational angiography

PURPOSE

This study aimed to evaluate the topographic features and branches of the middle meningeal artery (MMA) by three-dimensional rotational angiography (3DRA) and describe its variations' radiological classification based on previous clinical examples of cadaver studies and literature.

METHODS

We consecutively evaluated 87 cerebral hemispheres, including 32 females and 49 right sides between May 2020 and December 2021 who had undergone unilateral or bilateral cerebral and carotid artery 3D rotational angiography imaging by CCA injection and between 18 and 76-years-old. Maximum intensity projection images with 10-30 mm slice thickness were used for the morphological evaluations and measurements of MMA and its foramen, canal, and branches.

RESULTS

The diameters of the common carotid artery, internal carotid artery, and external carotid artery were significantly smaller in females than in men (p = 0.021, 0.021, and <0.001, respectively). According to the branching pattern, the most common pattern of the MMA was Type Ia (49.4%). The ophthalmic artery completely originated from MMA in the 1 (1.1%) cerebral hemisphere. The MMA arises from the ophthalmic artery in 2 cerebral hemispheres (2.3%), and the ophthalmic artery and maxillary artery in 2 cerebral hemispheres (2.3%).

CONCLUSION

It was observed that the branching pattern may show differences when compared to the cadaver studies with a radiologic evaluation with 3D-RA.

Morphometric and morphologic analysis of the foramen spinosum in the Slovenian population with clinical correlations

Background

The foramen spinosum (FS) is a pivotal passage for neurovascular structures within the skull base. We performed a detailed morphometric and morphological analysis of the FS to emphasize its clinical relevance.

Materials & Methods

The study was performed on dried skull specimens obtained from the anatomical collections of the Institute of Anatomy and Institute of Forensic Medicine of the University of Ljubljana. The morphometric and morphologic features of FS in 126 whole human skulls and 15 skull halves were analyzed, including dimensions, shape, and other anatomical variations, as well as relationships to surrounding structures. Measurements were done with a digital sliding caliper.

Results

The mean length and width of the FS were 2.45 ± 0.65 mm and 2.03 ± 0.53 mm on the right side and 2.49 ± 0.61 mm and 2.08 ± 0.48 mm on the left side. The most frequently observed shape was round (56.7%), followed by oval (28.2%), irregular (8.7%) and drop shaped (6.3%). Several anatomical variations were also noted, including FS duplication, confluences with other foramina, and FS obstruction due to marginal bony outgrowths.

Conclusion

The FS exhibits notable interindividual differences in anatomical characteristics which should be considered during neurosurgical procedures and radiological interventions in the skull base.

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.

Middle meningeal artery embolization for symptomatic chronic subdural hematoma in the setting of severe transfusion-refractory thrombocytopenia: A case study and review of literature

Background

Surgical decompression for the treatment of chronic subdural hematomas (cSDHs) is irrefutably effective; however, its utility in managing cSDH in patients with comorbid coagulopathy remains controversial. The optimal threshold for platelet transfusion in cSDH management is <100,000/mm³, according to guidelines from the American Association of Blood Banks GRADE framework. This threshold may be unachievable in refractory thrombocytopenia, though surgical intervention may still be warranted. We present a patient with symptomatic cSDH and transfusion-refractory thrombocytopenia successfully treated with middle meningeal artery embolization (eMMA). We also review the literature to identify management approaches for cSDH with severe thrombocytopenia.

Case Description

A 74-year-old male with acute myeloid leukemia presented to the emergency department with persistent headache and emesis following fall without head trauma. Computed tomography (CT) revealed a 12 mm right-sided, mixed density SDH. Platelets were <2000/mm³ initially, which stabilized to 20,000 following platelet transfusions. He then underwent right eMMA without surgical evacuation. He received intermittent platelet transfusions with platelet goal >20,000 and was discharged on hospital day 24 with resolving SDH on CT.

Conclusion

High-risk surgical patients with refractory thrombocytopenia and symptomatic cSDH may be successfully treated with eMMA without surgical evacuation. A platelet goal of 20,000/mm³ before and following surgical intervention proved beneficial for our patient. Similarly, a literature review of seven cases of cSDH with comorbid thrombocytopenia revealed five patients undergoing surgical evacuation following initial medical management. Three cases reported a platelet goal of 20,000. All seven cases resulted in stable or resolving SDH with platelets >20,000 at discharge.

Surgical techniques for evacuation of chronic subdural hematoma: a mini-review

Chronic subdural hematoma is one of the most common neurosurgical pathologies with over 160,000 cases in the United States and Europe each year. The current standard of care involves surgically evacuating the hematoma through a cranial opening, however, varied patient risk profiles, a significant recurrence rate, and increasing financial burden have sparked innovation in the field. This mini-review provides a brief overview of currently used evacuation techniques, including emerging adjuncts such as endoscopic assistance and middle meningeal artery embolization. This review synthesizes the body of available evidence on efficacy and risk profiles for each critical aspect of surgical technique in cSDH evacuation and provides insight into trends in the field and promising new technologies.

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.

Safety and radiologic clearance of chronic subdural hematoma after endovascular embolization using SQUID 18 in patients older than 80 years

The aim of the study was to evaluate radiographic clearance and clinical outcomes in patients over age 80 who undergo SQUID 18 embolization of the middle meningeal artery (MMA) for the management of chronic subdural hematoma (cSDH). From April 2020 to October 2021, data were obtained from patients with cSDH who underwent MMA embolization at our institution. Clinical and radiological data including pre-operative and last follow-up CT scans were analyzed. Six embolization procedures were performed in five patients using SQUID 18, a liquid embolic agent. The median age was 83 years, and three subjects were female. Two of the six cases were recurrent hematomas. MMA embolization was achieved in 100% of cases. The median diameter of the hematoma at admission was 20 mm and at last follow-up was 5.3 mm, demonstrating statistically significant radiographic clearance (P = 0.043). There were no intra or post-operative complications. Mortality was not noted during observation period. SQUID MMA embolization safely and significantly reduced the hematoma diameter and offers an alternative treatment in patients older than 80 years with cSDH.

A Novel Case of Deep Temporal Artery (DTA) Embolization for Recurrent Subacute-Chronic Subdural Hematoma

Subdural hemorrhage (SDH) is a common neurological disease. In past, SDHs were managed either conservatively (non-surgically) or with surgical evacuation (burr hole versus craniotomy) depending on the severity. Surgical evacuation has major challenges including high recurrence rate, stoppage and reversal of antiplatelet or anticoagulation agents, risk of general anesthesia and surgery in elderly patients with multiple comorbidities. Given the above challenges, embolization of the distal branches of the middle meningeal artery (MMA) has recently emerged as an excellent alternate to surgical evacuation or conservative management. To the best of our knowledge, there is no literature on the embolization of the deep temporal artery (DTA) for subacute-chronic SDH. We report the first case of recurrent subdural hematoma post MMA embolization that was successfully treated with embolization of DTA.

Chronic Subdural Hematoma after Craniotomy with Preoperative Embolization of Middle Meningeal Artery: A Case Report

Endovascular embolization of the middle meningeal artery (MMA) has been reported as an effective method for treating chronic subdural hematoma (CSDH); however, its preventive effect on CSDH following craniotomy is unknown. We present a case in which MMA embolization was ineffective in preventing CSDH following craniotomy. A 56-year-old man who complained of diplopia was diagnosed with sphenoid ridge meningioma with a 3-cm diameter. MMA embolization prior to the operation and total surgical removal of the tumor were performed. Two months postoperatively, the patient complained of headache and hemiparesis of the left side. CSDH with a 15-mm thickness and a midline shift was observed. MMA embolization before inflammation may not play a role in preventing CSDH development because MMA embolization is considered effective in CSDH because it is associated with the blood supply of neovessels that are newly formed due to inflammation. Therefore, MMA embolization might not be effective in preventing the occurrence of CSDH following craniotomy.

Single-cell profiling of human dura and meningioma reveals cellular meningeal landscape and insights into meningioma immune response

BACKGROUND

Recent investigations of the meninges have highlighted the importance of the dura layer in central nervous system immune surveillance beyond a purely structural role. However, our understanding of the meninges largely stems from the use of pre-clinical models rather than human samples.

METHODS

Single-cell RNA sequencing of seven non-tumor-associated human dura samples and six primary meningioma tumor samples (4 matched and 2 non-matched) was performed. Cell type identities, gene expression profiles, and T cell receptor expression were analyzed. Copy number variant (CNV) analysis was performed to identify putative tumor cells and analyze intratumoral CNV heterogeneity. Immunohistochemistry and imaging mass cytometry was performed on selected samples to validate protein expression and reveal spatial localization of select protein markers.

RESULTS

In this study, we use single-cell RNA sequencing to perform the first characterization of both non-tumor-associated human dura and primary meningioma samples. First, we reveal a complex immune microenvironment in human dura that is transcriptionally distinct from that of meningioma. In addition, we characterize a functionally diverse and heterogenous landscape of non-immune cells including endothelial cells and fibroblasts. Through imaging mass cytometry, we highlight the spatial relationship among immune cell types and vasculature in non-tumor-associated dura. Utilizing T cell receptor sequencing, we show significant TCR overlap between matched dura and meningioma samples. Finally, we report copy number variant heterogeneity within our meningioma samples.

CONCLUSIONS

Our comprehensive investigation of both the immune and non-immune cellular landscapes of human dura and meningioma at single-cell resolution builds upon previously published data in murine models and provides new insight into previously uncharacterized roles of human dura.

Middle Meningeal Artery Embolization for the Treatment of Bilateral Chronic Subdural Hematoma

Background: Bilateral chronic subdural hematoma (bCSDH) is a frequent condition commonly linked to the need for retreatment; however, the reason for this high retreatment rate remains unclear. The middle meningeal artery (MMA) was found to have a relationship with the occurrence and development of chronic subdural hematomas. This study examines a possible method to reduce bCSDH recurrence using bilateral MMA embolization combined with bilateral burr-hole drainage.

Materials and Methods: Ten patients with bCSDH who underwent bilateral MMA embolization combined with bilateral burr-hole drainage at our hospital between June 2018 and May 2020, were retrospectively analyzed. Patients' clinical information, prognoses, imaging results, as well as surgical results were documented and analyzed.

Results: Ten patients were diagnosed with bCSDH with no comorbid brain diseases. They underwent bilateral MMA embolization combined with bilateral burr-hole drainage. We embolized the MMA immediately before burr hole drainage successfully and employed angiography to validate these results. All the patients attained relief of symptoms without adverse events, and no re-expansion or relapse was reported in the follow-up computed tomography.

Conclusion: Bilateral MMA embolization combined with bilateral burr-hole drainage is an available treatment for patients with bCSDH and may have the potential for preventing recurrence.

Perioperative prophylactic middle meningeal artery embolization for chronic subdural hematoma: a series of 44 cases

OBJECTIVE

Chronic subdural hematoma (cSDH) is a common and challenging pathology to treat due to both the historically high recurrence rate following surgical evacuation and the medical comorbidities inherent in the aging patient population that it primarily affects. Middle meningeal artery (MMA) embolization has shown promise in the treatment of cSDHs, most convincingly to avoid surgical evacuation in relatively asymptomatic patients. Symptomatic patients requiring surgical evacuation may also benefit from perioperative MMA embolization to prevent cSDH recurrence. The goal of this study was to determine the utility of perioperative MMA embolization for symptomatic cSDH requiring surgical evacuation and to assess if there is a decrease in the cSDH recurrence rate compared to historical recurrence rates following surgical evacuation alone.

METHODS

Symptomatic cSDHs were evacuated using a subdural evacuating port system (SEPS) with 5-mm twist-drill craniostomy in an intensive care unit or by performing a craniotomy in the operating room, using either a small (silver dollar, < 4 cm) or large (≥ 4 cm) craniotomy. MMA embolization was performed perioperatively using angiography, selective catheterization of the MMA, and infusion of polyvinyl particles. Outcomes were assessed clinically and radiographically with interval head CT imaging.

RESULTS

There were 44 symptomatic cSDHs in 41 patients, with 3 patients presenting with bilateral symptomatic cSDH. All cSDHs were evacuated using an SEPS (n = 18), a silver-dollar craniotomy (n = 16), or a large craniotomy (n = 10). Prophylactic MMA embolization was performed successfully in all cSDHs soon after surgical evacuation. There were no deaths and no procedural complications. There was an overall reduction of greater than 50% or resolution of cSDH in 40/44 (90.9%) cases, regardless of the evacuation procedure used. Of the 44 prophylactic cases, there were 2 (4.5%) cases of cSDH recurrence that required repeat surgical evacuation at the 1-year follow-up. These 2 cSDHs were initially evacuated using an SEPS and subsequently required a craniotomy, thereby representing an overall 4.5% recurrence rate of treated cSDH requiring repeat evacuation. Most notably, of the 26 patients who underwent surgical evacuation with a craniotomy followed by MMA embolization, none had cSDH recurrence requiring repeat intervention.

CONCLUSIONS

Perioperative prophylactic MMA embolization in the setting of surgical evacuation, via either craniotomy or SEPS, may help to lower the recurrence rate of cSDH.

Selection of an Appropriate Surgical Method for the Management of Chronic Subdural Hematoma in a Patient with Poor Physical Status

Physical status is an important factor to consider when treating patients with chronic subdural hematomas. Surgical treatment of chronic subdural hematoma is mainly by burr hole trephination. However, operative methods must be selected after careful consideration of mortality, morbidity, and recurrence rates. In the case presented here, a chronic subdural hematoma was noted in a 65-year-old patient with several comorbidities; therefore, minimally invasive burr hole trephination was performed. After thrice repetition of the burr hole trephination procedure, a craniectomy for hematoma removal and middle meningeal artery embolization was finally conducted, followed by cranioplasty to treat a subsequent epidural hemorrhage. In the case discussed here, we review the options for the treatment of chronic subdural hematoma and evaluate the factors that should be considered in determining the appropriate surgical course. Despite poor patient physical status, minimally invasive operation may not always be the best option. If the patient is at high risk for recurrent subdural hematoma, craniotomy with hematoma removal may be a better choice.

Recurrence and Coniglobus Volumetric Resolution of Subacute and Chronic Subdural Hematoma Post-Middle Meningeal Artery Embolization

Objective: To study the efficacy of middle meningeal artery (MMA) embolization for the treatment of chronic subdural hematoma (SDH) and characterize its post-embolization volumetric resolution. Methods: Ten patients diagnosed with 13 cSDH underwent MMA embolization. SDH volumes were measured from time of initial discovery on imaging to pre-operative, post-operative, short-term and long-term follow-up. Time between procedure to obliteration was also measured. Volumetric analysis was done using the coniglobus formula, and recurrence rate as well as resolution timeline was defined using best-fit models. Results: Out of 10 patients, five were recurrent lesions, three were bilateral and seven unilateral cSDH. Average and median pre-operative volumes were 105.3 cc and 97.4 cc, respectively. Embolization on average was performed 21 days after discovery. Sixty percent of patients had concurrent antiplatelets or anticoagulation use. Forty percent underwent embolization treatment as the primary therapy. Recurrence was not seen in any patients treated with embolization. There were no peri- or post-operative complications. Five patients experienced complete or near-complete obliteration, while those with partial resolution showed a composite average of 75% volumetric reduction in 45 days. Post-embolization, the volumetric resolution followed an exponential decay curve over time and was independent of initial volume. Conclusion: MMA embolization contributed to a marked reduction in SDH volume post-operatively and can be used as a curative therapy for primary or recurrent chronic SDH.

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: Anatomy and Variations

The middle meningeal artery is the major human dural artery. Its origin and course can vary a great deal in relation, not only with the embryologic development of the hyostapedial system, but also because of the relationship of this system with the ICA, ophthalmic artery, trigeminal artery, and inferolateral trunk. After summarizing these systems in the first part our review, our purpose is to describe, in this second part, the anatomy, the possible origins, and courses of the middle meningeal artery. This review is enriched by the correlation of each variant to the related embryologic explanation as well as by some clinical cases shown in the figures. We discuss, in conclusion, some clinical conditions that require detailed knowledge of possible variants of the middle meningeal artery.

Application of Absolute Alcohol in the Treatment of Traumatic Intracranial Hemorrhage via Interventional Embolization of Middle Meningeal Artery

Background: Traumatic brain injury is a common condition in neurosurgery. Traditional methods of treatment include conservative treatment and surgical evacuation using burr-holes or craniotomy; however, studies have reported problems such as high re-expansion rates after conservative treatment of epidural hematoma and high postoperative recurrence rates of subdural hematoma. Solutions to these problems are lacking, and research into new treatment methods is ongoing. Among the potential new treatments, middle meningeal arterial embolization is an option. This study involved patients with acute epidural hematoma and chronic subdural hematoma. The purpose was to evaluate the use and effects of absolute alcohol to embolize the middle meningeal artery to treat intracranial hematoma. Material and Methods: A retrospective description study was 12 cases of intracranial hematoma who treated with absolute alcohol interventional therapy from our hospital between June 2018 and October 2019. Five patients with acute epidural hematoma and seven patients with chronic subdural hematoma were treated using absolute alcohol to embolize the middle meningeal artery. Patients' clinical data, imaging results, surgical results, and prognosis were recorded and analyzed. Results: All patients underwent absolute alcohol embolization of the middle meningeal artery, in combination with burr-hole drainage. All imaging data were confirmed preoperatively. We successfully used absolute alcohol to embolize the middle meningeal artery intraoperatively and confirmed these results by postoperative angiography. All patients achieved symptomatic relief without complications, and no recurrence or re-expansion was seen with follow-up computed tomography. Our study has been registered in the Chinese Clinical Trial Registry (http://www.chictr.org.cn, ChiCTR1800018714). Conclusion: The use of absolute alcohol to embolize the middle meningeal artery could be used as an attempt to treat acute epidural hematoma and chronic subdural hematoma.

Benefits of the Subdural Evacuating Port System (SEPS) Procedure Over Traditional Craniotomy for Subdural Hematoma Evacuation

Background

There remains no consensus on the optimal primary intervention for subdural hematoma (SDH). Although historically favored, craniotomy carries substantial morbidity and incurs significant costs. Contrastingly, the subdural evacuating port system (SEPS) is a minimally invasive bedside procedure. We assessed the benefits of SEPS over traditional craniotomy for SDH evacuation.

Methods

A single-center retrospective cohort study of SDH patients receiving craniotomy or SEPS between 2012 and 2017 was performed. Information regarding demographics, medical history, presentation, surgical outcomes, cost, and complications was collected. Pre- and postoperative hematoma volumes were calculated using 3D image segmentation using Vitrea software. Multivariate regression models were employed to assess the influence of intervention choice.

Results

Of 107 patients, 68 underwent craniotomy and 39 underwent SEPS. There were no differences in age, sex, blood thinner use, platelet count, INR, hematoma lateralization, age, volume, or midline shift at presentation between intervention groups. Although there was no difference in percent residual hematoma volume 24-hour postintervention (44.1% vs 45.1%, P = .894), SEPS was associated with lower hospitalization costs ($108 391 vs $166 318, *P = .002), shorter length of stay (4.0 vs 5.8 days, *P = .0002), and fewer postoperative seizures (2.6% vs 17.7%, *P = .048). Reoperation rate was higher after SEPS overall (33.3% vs 13.2%, *P = .048) but comparable to craniotomy in chronic SDH (12.50% vs 7.69%, P = 1.000).

Conclusion

In this retrospective cohort, SEPS was noninferior to craniotomy at reducing SDH hematoma volume. The SEPS procedure was also associated with decreased length of stay hospitalization costs, and postoperative seizures and demonstrated a comparable recurrence rate to craniotomy for chronic SDH in particular.

Efficacy and safety of middle meningeal artery embolization in the management of refractory or chronic subdural hematomas: a systematic review and meta-analysis

INTRODUCTION

Refractory or chronic subdural hematomas (cSDH) constitute a challenging entity that neurosurgeons face frequently nowadays. Middle meningeal artery embolization (MMAE) has emerged in the recent years as a promising treatment option. However, solid evidence that can dictate management guidelines is still lacking.

METHODS

We conducted a systematic review and meta-analysis (MA) in compliance with the PRISMA guidelines to evaluate the efficacy and safety of MMAE compared with conventional treatments for refractory or cSDH. Databases were searched up to March 2019. Using a random-effects model, meta-analyses of proportions and risk difference were conducted recurrence, need for surgical rescue, and complications.

RESULTS

Eleven studies (177 patients) were included. Majority (116, 69%) were males with a weighted mean age of 71 + -19.5 years. Meta-analysis of proportions showed treatment failure to be 2.8%, need for surgical rescue 2.7%, and embolization-related complications 1.2%. Meta-analysis of risk-difference between embolized and non-embolized patients showed a 26% (p < 0.001, 95% CI 21%-31%, I² = 0) lower risk of hematoma recurrence in MMAE. Similarly, in the embolized group, the need for surgical rescue was 20% less (p < 0.001, 95% CI = 12%-27%, I² = 12.4), and complications were 3.6% less (p = 0.008, 95% CI 1%-6%, I² = 0) compared to conventional groups.

CONCLUSIONS

Although MMAE appears to be a promising treatment for refractory or cSDH, drawing definitive conclusions remains limited by paucity of data and small sample sizes. Multicenter, randomized, prospective trials are needed to compare embolization to conventional treatments like watchful waiting, medical management, or surgical evacuation. More extensive research on MMAE could begin a new era in the minimally invasive management of cSDH.

Middle meningeal artery embolization as an adjuvant treatment to surgery for symptomatic chronic subdural hematoma: a pilot study assessing hematoma volume resorption

Background

Chronic subdural hematoma (CSDH) is a common condition requiring surgical treatment; however, recurrence occurs in 15% of cases at 1 year. Middle meningeal artery (MMA) embolization has recently emerged as a promising treatment to prevent CSDH recurrence.

Objective

To investigate the effect of MMA embolization on hematoma volume resorption (HVR) after surgery in symptomatic patients.

Methods

From April 2018 to October 2018, participants with CSDH requiring surgery were prospectively randomized in a pilot study, and received either surgical treatment alone (ST group) or surgery and adjuvant MMA embolization (ST+MMAE group). The primary outcome was HVR measured on the 3 month CT scan compared with the immediate pre-embolization CT scan. Secondary outcomes were clinical recurrence of CSDH and safety measures.

Results

46 patients were randomized and 41 of these achieved a 3 month follow-up . Twenty-one patients received MMA embolization. At 3 months, the HVR from postsurgical level was higher in the ST+MMAE group (mean difference 17.5 mL, 95% CI 3.87 to 31.16 mL; p=0.015). Two participants presented a CSDH recurrence (one in each group). One patient died (ST group). No MMA embolization-related adverse events were reported.

Conclusion

The addition of MMA embolization to surgery led to an increase in CSDH resorption at 3 months. One recurrence of CSDH was reported in each group, and there were no treatment-related complications.

Ultrasonographic assessment of the maxillary artery and middle meningeal artery in the infratemporal fossa

PURPOSE

To investigate with Doppler ultrasonography the maxillary and middle meningeal arteries in the infratemporal fossa, and describe their hemodynamic characteristics.

METHODS

We included 24 female and 11 male volunteers without vascular diseases, with a median age of 43 years. We used the acoustic window, enlarged by subjects half-opening their mouth, located below the zygomatic arch, in front of temporo-mandibular joint, to reach the maxillary and middle meningeal arteries.

RESULTS

In the 35 subjects, 112 arteries were visualized successfully: 60 maxillary (85.7%), and 52 middle meningeal arteries (74.3%), at a depth of 2.40 and 2.50 cm, respectively. Their blood flow was directed anteriorly and away from the probe. While all the measured hemodynamic characteristics differed significantly between the maxillary and the middle meningeal artery (P < 0.001), there was no significant difference between male and female subjects, nor between the left or the right side.

CONCLUSIONS

The maxillary and middle meningeal arteries can be insonated in the infratemporal fossa through the easily accessible acoustic window below the zygomatic arch, when the patient holds his mouth half open. They can be differentiated by their ultrasonographic characteristics and blood flow features.

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.

Contrast enhancement of chronic subdural hematomas after embolization of the middle meningeal artery

Chronic subdural hematomas are a common neurosurgical presentation. They are difficult to treat, and current interventions - namely surgical evacuation - are not without complications or recurrences. Embolization of the middle meningeal artery is a promising new treatment option for this pathology. We have noted an interesting phenomenon in our patients following endovascular embolization, which is that the subdural hematoma is stained with contrast following the procedure. This ties into the basic physiology of chronic subdurals, which parasitize the middle meningeal artery during the process of membrane formation and neovascularization, which has previously been reported.

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.

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: Endovascular technique and radiographic findings

Background and purpose Embolization of the middle meningeal artery (MMA) has recently been proposed as an alternative to surgery for treatment of chronic subdural hematoma (SDH), and several case reports have been published supporting its efficacy. It has been suggested that the primary pathologic process in chronic SDH is repeated microhemorrhaging into the subdural collection from fragile neovasculature within the SDH membrane that arises from distal branches of the MMA. Embolization could thus provide a means of eliminating this chronic rebleeding. Materials and methods Images were selected from MMA embolization procedures performed at our institution in order to illustrate the technique and theory behind its efficacy for treatment of chronic SDH. Results Images from MMA angiograms demonstrate the variability of MMA anatomy and help illustrate the importance of avoiding potential ophthalmic collaterals and branches supplying cranial nerves. The findings of irregular wispiness of the distal MMA vasculature, contrast outlining of the SDH membrane on angiography, and homogenous increased density within the SDH on postembolization head computed tomography are described. Conclusion MMA embolization may provide a safe alternative for treatment of chronic SDH, but careful angiographic assessment of MMA anatomy should be performed to avoid potential complications. The findings illustrated here lend support to the theory that the pathologic process of chronic SDH is repeated leakage of blood products from an inflamed, abnormal arterial neovasculature within the SDH membrane that arises from the MMA, and thus selective embolization could provide an effective treatment.