Comparison of adjunctive middle meningeal artery embolization using embosphere particles versus surgical drainage alone for the treatment of chronic subdural hematoma: A prospective study.

BACKGROUND: Middle meningeal artery embolization (MMAE) has emerged as a primary and adjunctive therapy for chronic subdural hematoma (CSDH) in addition to conventional treatment. However, there is a scarcity of data that explicitly compares the effectiveness of adjunctive MMAE to surgical drainage alone (SDA), as well as the use of Embosphere particles. The objective of this study was to assess the safety and efficacy of adjunctive MMAE in the treatment of symptomatic CSDH compared to SDA. METHODS: This prospective study included 43 patients with 52 CSDH sides, treated at a single institution between 2022 and 2023. The primary outcome was postoperative hematoma volume at 14, 30, 90, and 180 days after surgical drainage, which was analyzed using the generalized estimating equation. The secondary outcomes were the complications and recurrence/reoperation rate. Adjunctive MMAE was performed within 7 days following the surgery, utilizing Embosphere as the embolic material. RESULTS: The patients were assigned to either the adjunctive MMAE group (n = 20, 26 CSDH sides) or the SDA group (n = 23, 26 CSDH sides). The adjunctive MMAE group demonstrated a more significant reduction in hematoma volume (p = 0.007) and maximal hematoma thickness (p = 0.016) at all follow-up intervals. A trend towards lower recurrence and reoperation rates was observed with adjunctive MMAE; particularly, none of the patients in the adjunctive MMAE group experienced a recurrence of CSDH, compared to 19.2 % in the SDA group (p = 0.051). One procedural-related complication (3.8 %) in the adjunctive MMAE group. CONCLUSION: Our results suggested that adjunctive MMAE, compared to SDA, may enhance hematoma resolution and reduce the need for reoperation due to recurrence.

Middle meningeal artery embolization following surgical evacuation of symptomatic chronic subdural hematoma improves outcomes, interim results of a prospective randomized trial.

BACKGROUND: Outcomes after surgical treatment of chronic subdural hematoma (cSDH) remain undesirable in a significant proportion of patients. We aimed to show the role of middle meningeal artery (MMA) embolization and to demonstrate its benefits. METHODS: Thirty-five patients with symptomatic cSDH were enrolled in a prospective randomized trial following evacuation surgery. Participants were randomized to embolization or control group (expectant management following surgical evacuation without embolization). Patients were followed throughout their hospitalization and outpatient follow-ups. The main goals of this planned interim analysis were to assess neurological outcome and resource utilization. RESULTS: The groups were comparable in terms of sex, age and follow-up retention rates. Side(s) of intervention(s) and hematoma size were similar. There was no statistical difference in neurological examination improvement at discharge, but at follow-up, we observed a decline in neurologic exam in the control group (p = 0.03). Control group participants required more re-interventions (p = 0.02) and were followed in clinic and during related readmissions for longer (p = 0.02). The number of imaging studies obtained in relation to the disease management was higher in the control group (p = 0.01). CONCLUSIONS: Our results suggest a beneficial role for the addition of MMA embolization to surgical intervention in the treatment of symptomatic chronic subdural hematoma. Neurological outcomes were significantly better in the embolization group. This contributed to less need for follow-up, re-interventions, and imaging studies.

Sex differences in CGRP-induced vasodilation of human middle meningeal arteries but not human coronary arteries: implications for migraine.

BACKGROUND: Migraine prevalence and levels of calcitonin gene-related peptide (CGRP), a peptide involved in migraine pathophysiology, differ between men and women, and appear to be affected by changes in sex hormones. The present study investigated the sex-specific responses to CGRP in human isolated arteries. METHODS: CGRP-induced relaxation of 62 (28 men and 34 women) human isolated middle meningeal arteries (HMMA) and 139 (69 men and 70 women) human isolated coronary arteries (HCA) was compared between men and women in groups <50 years and ≥50 years of age as a proxy for pre- and postmenopausal status in women, as well as matched-age groups for men. RESULTS: In HCA, no differences were observed between male and female tissue, or between the different age groups. However, in HMMA, the maximum response was significantly smaller and CGRP was less potent in females <50 compared with males <50 years of age. No differences were observed between the older age groups. CONCLUSIONS: Sex differences were observed for CGRP-induced relaxation of HMMA, but not HCA. These differences could arise from differential receptor expression in the vascular beds combined with the effect of sex hormones on CGRP and subsequent receptor desensitization.

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

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

Factors Associated with Extended Hospitalization in Patients Who Had Adjuvant Middle Meningeal Artery Embolization After Conventional Surgery for Chronic Subdural Hematomas.

BACKGROUND: This study aims to evaluate the length of stay (LOS) in patients who had adjunct middle meningeal artery embolization (MMAE) for chronic subdural hematoma after conventional surgery and determine the factors influencing the LOS in this population. METHODS: A retrospective review of 107 cases with MMAE after conventional surgery between September 2018 and January 2024 was performed. Factors associated with prolonged LOS were identified through univariable and multivariable analyses. RESULTS: The median LOS for MMAE after conventional surgery was 9 days (interquartile range = 6-17), with a 3-day interval between procedures (interquartile range = 2-5). Among 107 patients, 58 stayed ≤ 9 days, while 49 stayed longer. Univariable analysis showed the interval between procedures, type of surgery, MMAE sedation, and the number of complications associated with prolonged LOS. Multivariable analysis confirmed longer intervals between procedures (odds ratio [OR] = 1.52; P < 0.01), ≥2 medical complications (OR = 13.34; P = 0.01), and neurological complications (OR = 5.28; P = 0.05) were independent factors for lengthier hospitalizations. There was a trending association between general anesthesia during MMAE and prolonged LOS (P = 0.07). Subgroup analysis revealed diabetes (OR = 5.25; P = 0.01) and ≥2 medical complications (OR = 5.21; P = 0.03) correlated with a LOS over 20 days, the 75th percentile in our cohort. CONCLUSIONS: The interval between procedures and the number of medical and neurological complications were strongly associated with prolonged LOS in patients who had adjunct MMAE after open surgery. Reducing the interval between the procedures and potentially performing both under 1 anesthetic may decrease the burden on patients and shorten their hospitalizations.

Middle Meningeal Arterial Embolization Combined With Drilling in the Treatment of Acute Epidural Hematoma.

OBJECTIVE: The purpose of this study was to determine the technical feasibility and safety of middle meningeal arterial (MMA) embolization combined with drilling drainage in the treatment of acute epidural hematoma (AEDH) by comparing it with traditional craniotomy in the treatment. METHODS: One hundred seventeen patients with AEDH treated for MMA embolization combined with drilling and drainage or craniotomy hematoma removal from January 2017 to September 2020 were retrospectively analyzed and divided into a craniotomy group (n=85) and a minimally invasive group (n=32). Hematoma removal was performed in the craniotomy group, and MMA embolization combined with drilling and drainage was performed in the minimally invasive group. The general clinical data, imaging data, surgery, and follow-up of the 2 groups were compared and analyzed. RESULTS: Compared with the craniotomy group, the residual hematoma volume in the minimally invasive group was higher than in the craniotomy group. The average postoperative drainage duration in the minimally invasive group was longer than in the craniotomy group. Compared with the craniotomy group, the minimally invasive group was associated with shorter operative time, less intraoperative bleeding, and lower rates of postoperative rebleeding. In addition, the incidence of postoperative complications and length of hospitalization in the minimally invasive group were significantly shortened. CONCLUSION: Middle meningeal arterial embolization combined with drilling and drainage in the treatment of AEDH caused by MMA active bleeding is safe, effective, and more minimally invasive, and can be promoted and applied.

Modified craniotomy procedures and virtual reality technology for accurate localization of the frontal branch of MMA in revascularization surgery.

The frontal branch of middle meningeal artery (MMA) can easily be damaged during revascularization surgery. To precise locate it and minimize its injury, we propose a set of modified craniotomy procedures combined with simple virtual reality (VR) technology based on three-dimensional (3D) Slicer simply, economically, and efficiently. Patients with Moyamoya disease (MMD) and internal carotid artery occlusion (ICAO) who received revascularization from January 2015 to December 2022 were divided into two groups based on the methods used to locate the MMA: traditional methods and precise MMA locating with VR technology. Patient demographics and clinical characteristics were analyzed to compare the preservation rates of MMA. The distances between this artery and bony anatomical landmarks were also measured to better understand its localization. There was no significant difference in baseline characteristics between the two groups. The precise MMA locating group exhibited a significantly higher preservation rate of the frontal branch of MMA (p = 0.037, 91.7% vs. 68.2%). Over 77% of patients had their frontal branch of MMA partially or completely surrounded by bony structures to varying degrees. Therefore, the combination of modified craniotomy procedures, 3D Slicer, and simple VR technology represents an economical, efficient, and operationally simple strategy.

[External Carotid Artery:Essential Knowledge of the External Carotid Artery Required for Neuroendovascular Surgery, with a Focus on the Middle Meningeal Artery and Occipital Artery].

The perfusion territory of the external carotid artery is often underestimated; however, this blood vessel forms abundant "dangerous anastomoses" with the internal carotid and vertebral arteries. An understanding of these vascular anastomoses is crucial to ensure safe cerebrovascular interventions. There are several important aspects of the middle meningeal artery that should be considered, including anastomoses with the anterior(frontal)branch and ophthalmic artery through the sphenoidal artery(recurrent meningeal artery)and meningolacrimal artery. Additionally, the blood supply to the facial nerve via branches of the petrosal branch, such as the superior tympanic artery, and the formation of the facial arcade by the superior tympanic and stylomastoid arteries, which often originate from the posterior auricular artery, is significant. The occipital artery demonstrates rich anastomoses with vessels, such as the ascending pharyngeal and vertebral arteries, forming what is known as the pharyngo-occipital system.

[The Ascending Pharyngeal Artery, Accessory Meningeal Artery, Lingual Artery, Vasa Nervorum, and Potential Anastomotic Channels].

The ascending pharyngeal, accessory meningeal, and lingual arteries branch from the proximal segment of the external carotid artery. These branches give rise to smaller branches that contribute blood supply to the pharyngeal mucosa, parapharyngeal tissue, middle ear, submandibular tissues, tongue, and dura mater of the middle and posterior fossa. These arteries may also supply the cranial nerves and have potential anastomotic channels that function with the internal carotid and vertebral arteries. M igration of embolic material into the vasa nervorum and potential anastomoses may cause complications. Therefore, knowledge of these functional anatomies is crucial for neuro-interventionalists.

Absence and Duplicate Foramen Spinosum in the Same Patient: An Extremely Rare Variation.

The foramen spinosum, one of the important openings at the base of the cranium, is the opening through which the middle meningeal artery enters the cranium. The variations of the foramen spinosum should be well known to be an important landmark in middle fossa surgeries and to understand better the clinical conditions related to the middle meningeal artery passing through it. A total of 35 bones (32 cranial base and 3 separate sphenoid bones) of individuals of unknown age, sex, and ethnicity in the Laboratory of the Department of Anatomy, Gaziantep University, Faculty of Medicine were examined bilaterally in this study. One of the 35 bones was found to have a duplicated foramen spinosum on the left side and an absence foramen spinosum on the right side. Foramen spinosum variations should be considered in middle fossa approaches and procedures involving the middle meningeal artery.

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

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

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

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

Middle Meningeal Artery Embolization for Management of Chronic Subdural Hematoma.

Chronic subdural hematoma (CSDH) is a prevalent medical condition with potentially severe consequences if left untreated. While surgical removal has traditionally been the standard approach for treatment, middle meningeal artery (MMA) embolization has emerged as a promising minimally invasive alternative to reduce recurrences. This comprehensive review provides the general radiology community with an overview of MMA embolization as a therapeutic option for managing CSDH. The authors base their insights on existing evidence and their institutional experience. This overview encompasses the pathophysiology of CSDH as well as the potential advantages and limitations, safety profile, and potential complications of MMA embolization as compared with surgical treatment. The imaging findings seen before and after MMA, as well as insights into the procedural techniques used at the authors' institution, are described. On the basis of reports in the current literature, MMA embolization appears to be a safe and effective therapeutic option for managing CSDH, especially in patients who are unsuitable for surgery or at risk for recurrence. Nonetheless, further research is needed to validate these findings. Results from ongoing clinical trials hold promise for future validation and the establishment of scientific evidence. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material. See the invited commentary by Chatterjee in this issue.

Middle meningeal artery embolization reduces recurrence following surgery for septated chronic subdural hematomas.

BACKGROUND: Septated chronic subdural hematomas (cSDH) have high rates of recurrence despite surgical evacuation. Middle meningeal artery embolization (MMAE) has emerged as a promising adjuvant for secondary prevention, yet its efficacy remains ill-defined. METHODS: This is a retrospective review of septated cSDH cases treated at our institution. The surgery-only group was derived from cases performed before 2018, and the surgery+MMAE group was derived from cases performed 2018 or later. The primary outcome was reoperation rate. Secondary outcomes were recurrence, change in hematoma thickness, and midline shift. RESULTS: A total of 34 cSDHs in 28 patients (surgery+MMAE) and 95 cSDHs in 83 patients (surgery-only) met the inclusion criteria. No significant difference in baseline characteristics between groups was identified. The reoperation rate was significantly higher in the surgery-only group (n = 16, 16.8%) compared with the surgery+MMAE cohort (n = 0, 0.0%) (p=0.006). A reduced incidence of recurrence (p=0.011) was also seen in the surgery+MMAE group. CONCLUSIONS: MMAE for septated cSDH was found to be highly effective in preventing recurrence and reoperation. MMAE is an adjunct to surgical evacuation may be of particular benefit in this patient cohort.

The Influence of Coagulopathy on Radiographic and Clinical Outcomes in Patients Undergoing Middle Meningeal Artery Embolization as Standalone Treatment for Non-acute Subdural Hematomas.

Middle meningeal artery embolization (MMAE) is emerging as a safe and effective standalone intervention for non-acute subdural hematomas (NASHs); however, the risk of hematoma recurrence after MMAE in coagulopathic patients is unclear. To characterize the impact of coagulopathy on treatment outcomes, we analyzed a multi-institutional database of patients who underwent standalone MMAE as treatment for NASH. We classified 537 patients who underwent MMAE as a standalone intervention between 2019 and 2023 by coagulopathy status. Coagulopathy was defined as use of anticoagulation/antiplatelet agents or pre-operative thrombocytopenia (platelets <100,000/µL). Demographics, pre-procedural characteristics, in-hospital course, and patient outcomes were collected. Thrombocytopenia, aspirin use, antiplatelet agent use, and anticoagulant use were assessed using univariate and multivariate analyses to identify any characteristics associated with the need for rescue surgical intervention, mortality, adverse events, and modified Rankin Scale score at 90-day follow-up. Propensity score-matched cohorts by coagulopathy status with matching covariates adjusting for risk factors implicated in surgical recurrence were evaluated by univariate and multivariate analyses. Minimal differences in pre-operative characteristics between patients with and those without coagulopathy were observed. On unmatched and matched analyses, patients with coagulopathy had higher rates of requiring subsequent surgery than those without (unmatched: 9.9% vs. 4.3%; matched: 12.6% vs. 4.6%; both p < 0.05). On matched multivariable analysis, patients with coagulopathy had an increased odds ratio (OR) of requiring surgical rescue (OR 3.95; 95% confidence interval [CI] 1.68-9.30; p < 0.01). Antiplatelet agent use (ticagrelor, prasugrel, or clopidogrel) was also predictive of surgical rescue (OR 4.38; 95% CI 1.51-12.72; p = 0.01), and patients with thrombocytopenia had significantly increased odds of in-hospital mortality (OR 5.16; 95% CI 2.38-11.20; p < 0.01). There were no differences in follow-up radiographic and other clinical outcomes in patients with and those without coagulopathy. Patients with coagulopathy undergoing standalone MMAE for treatment of NASH may have greater risk of requiring surgical rescue (particularly in patients using antiplatelet agents), and in-hospital mortality (in thrombocytopenic patients).

Tumor Embolization via the Meningohypophyseal and Inferolateral Trunk in Patients with Skull Base Tumors Using the Distal Balloon Protection Technique.

BACKGROUND AND PURPOSE: Tumor embolization through the meningohypophyseal trunk and inferolateral trunk is known to be effective in skull base tumors; however, microcatheter cannulation into these arteries is difficult, and the number of cases that can be safely embolized is limited. In this study, we present a novel embolization procedure for the meningohypophyseal trunk and inferolateral trunk using the distal balloon protection technique and detail its clinical efficacy and complication risks. We developed this procedure to allow safe embolization in patients who cannot be adequately cannulated with microcatheters into these arteries. MATERIALS AND METHODS: Patients who underwent meningohypophyseal trunk or inferolateral trunk embolization using the distal balloon protection technique for skull base tumors at our institution between 2010 and 2023 were included. In this procedure, the ICA was temporarily occluded with a balloon at the ophthalmic artery bifurcation, the microcatheter was guided to the meningohypophyseal trunk or inferolateral trunk vicinity, and embolic particles were injected into the arteries. The balloon was deflated after the embolic particles that had refluxed into the ICA were aspirated. RESULTS: A total of 25 meningohypophyseal trunks and inferolateral trunks were embolized during 21 operations. Of these 25 arteries, only 9 (36.0%) were successfully cannulated with microcatheters. Nevertheless, effective embolization was achieved in all cases. Permanent complications occurred in only 1 case (4.8%) in which the central retinal artery was occluded during inferolateral trunk embolization, resulting in a visual field defect. No permanent complications resulting from the embolic cerebral infarction were observed. Of 16 cases that underwent MR imaging within a week after embolization, however, 11 (68.8%) demonstrated embolic cerebral infarctions. CONCLUSIONS: In patients with skull base tumors with meningohypophyseal trunk or inferolateral trunk feeders that cannot be catheterized directly, embolization using the distal balloon protection technique for tumor supply can be considered as a salvage technique.