Traumatic middle meningeal arteriovenous fistulas (MMAVFs): an exploratory systematic review.

This study aims to systematically review case reports and case series in order to compare the postoperative course of conservative, endovascular and surgical treatments for traumatic dural arteriovenous fistulas predominantly supplied by the middle meningeal artery (MMAVFs), which usually occur following head trauma or iatrogenic causes. We conducted a comprehensive search of PubMed, Embase, Scopus, Web of Science, and Google Scholar until June 23rd, 2024. Three cohorts were defined based on the treatment modality employed. The primary outcomes were the rates of overall obliteration and postoperative complications, with all-cause mortlality considered as secondary outcome. A total of 61 studies encompassing 78 pooled MMAVFs were included in the qualitative analysis. The predominant demographic consisted of males (53.9%) with a median age of 50.5 (IQR: 33.5-67.5) years. The main etiologies for fistula formation were head trauma (75.6%), cranial neurosurgical procedures (11.5%) and endovascular embolization (8.97%). Venous drainage patterns were categorized as follows based on anatomical confluence: Class I (16.7%), II (14.1%), III (12.8%), IV (14.1%), V (7.7%), and VI (3.9%). Regarding treatment efficacy, the overall obliteration rate was 89.74%, achieved through endovascular (95.83%), surgical (64.29%) or conservative (93.75%) approaches. In terms of safety, the overall postoperative complication rate was 6.49% with an all-cause mortality rate of 8.97%, predominantly observed in the surgical group (35.71%). Our systematic review highlights the challenging management of traumatic MMAVFs, frequently associated with head injuries. Endovascular therapy has emerged as the predominant treatment modality, demonstrating markedly higher rates of fistula obliteration, reduced all-cause mortality, and fewer postoperative complications.

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.

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.

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

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

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.

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.

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.

Initial experience using middle meningeal artery embolisation for patients with recurrent and high-recurrence-risk chronic subdural haematoma.

Recurrence rates following surgical management of chronic subdural haematoma (CSDH) range from 5 to 33 %. There is growing evidence which suggests middle meningeal artery embolisation (MMAe) may reduce recurrence rates when used as surgical adjunct or standalone treatment. In this study we described our experience of this new procedure in the our UK institution. Patients with recurrent CSDH or CSDH at high risk of recurrence were selected for MMAe on a case-by-case basis following MDT discussion. A departmental database was used to identify patients treated. 26 CSDH were embolised in 20 patients; 9 CSDH were de-novo and 17 were recurrent. 10/26 CSDH were treated with MMAe only. No procedural mortality, access site or thrombo-embolic complications occurred. One patient experienced symptomatic collection growth 12 h following MMAe and required surgical drainage. 15 (75 %) of patients were living at home at follow-up (mean 14 months). On imaging follow-up 15/18 showed CSDH volume reduction or resolution, 1/18 remained stable requiring no further treatment, 2/18 patients suffered recurrent CSDH requiring treatment. In both recurrent cases incomplete embolisation was noted on procedural imaging (posterior division of MMA not embolised). Persistent posterior MMA division filling was significantly associated with collection recurrence (p = 0.002). Our results suggest MMAe as a stand-alone or adjuvant therapy can be performed safely in a UK neuroscience setting and is associated with high rates of symptomatic CSDH size reduction or resolution in problematic CSDH that have either recurred or are prone to recurrence.

[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.

[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 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.