Adjunctive middle meningeal artery embolization superior to standard care in symptomatic chronic subdural hematomas

1. In this randomized controlled trial, middle meningeal artery embolization demonstrated a decreased risk of treatment failure in patients with symptomatic chronic subdural hematoma as compared to standard care. 

2. Middle meningeal artery embolization did not increase the incidence of disabling stroke or death.

Evidence Rating Level: 1 (Excellent)

Study Rundown: Chronic subdural hematoma is a common neurosurgical disease that most frequently presents in older adults. Currently, there are no widely accepted evidence-based guidelines for the treatment of chronic subdural hematoma. For symptomatic cases, surgical evacuation is generally favored, whereas, for asymptomatic smaller collections, non-surgical management is preferred. Unfortunately, both treatment strategies are associated with a relatively high risk of treatment failure. This often leads to reoperation, surgical rescue, or complications such as stroke, myocardial infarction, or death. It has been hypothesized that chronic subdural hematoma is caused by a cycle of inflammation of the meninges, leading to neovascular growth that is susceptible to bleeding into the subdural space, which further perpetuates inflammation. Embolization of the middle meningeal artery with liquid agents can occlude the pathologic meningeal neovasculature, which may shift the balance in favor of physiologic reabsorption of the collection. This randomized controlled trial investigated the effect of adjunctive middle meningeal artery embolization with Squid, a nonadhesive liquid embolic agent, on the risk of treatment failure among patients receiving surgical or nonsurgical standard treatment for chronic subdural hematoma. Patients who met inclusion criteria were randomly assigned to undergo middle meningeal artery embolization as an adjunct to standard therapy or standard therapy alone. The primary endpoint was a composite measure of several events, including recurrent or residual hematoma, reoperation, or stroke. Results from the study found that adjunctive middle meningeal artery embolization resulted in a lower risk of treatment failure than standard therapy alone in patients with symptomatic subdural hematoma.

Click here to read the study in NEJM

In-Depth [randomized controlled trial]: This randomized controlled trial assessed the effect of middle meningeal artery embolization with Squid, a non-adhesive liquid embolic agent, on the risk of treatment failure among patients receiving surgical or non-surgical standard treatment for chronic subdural hematoma. Adult patients were eligible for this trial if they had symptomatic chronic subdural hematoma measuring greater than 10mm in thickness on imaging. Patients were excluded if they had a score greater than 1 on the modified Rankin scale before symptoms related to hematoma developed or if they had undergone craniotomy for the hematoma. A total of 310 patients were randomly assigned to undergo middle meningeal artery embolization as an adjunct to standard treatment (n = 149) or to receive standard treatment alone (n = 161). Of the patients recruited, 189 received surgical standard treatment and 121 received non-surgical standard treatment. The primary outcome was a composite of the following events: recurrent or residual chronic subdural hematoma (measuring >10 mm) at 180 days; reoperation or surgical rescue within 180 days; or major disabling stroke, myocardial infarction, or death from neurologic causes within 180 days. In the primary outcome analysis, an outcome event occurred in 19/120 (16%) of the embolization group, compared to 47/129 patients (36%) in the control group (odds ratio, 0.36; 95% confidence interval, 0.20 to 0.66; p=0.001). The primary safety outcome was a composite of major disabling stroke or death from any cause within 30 days. The primary analysis found that 4/144 patients (3%) in the embolization group and 5/166 patients (3%) in the control group had either a major disabling stroke or died within 30 days. Through the 180 days, 12 patients (8%) in the embolization group and 9 patients (5%) in the control group had died. Overall, results from this study found that adjunctive middle meningeal artery embolization resulted in a lower risk of treatment failure than standard therapy alone in patients with symptomatic subdural hematoma. Additionally, adjunctive therapy with middle meningeal artery embolization did not result in an increased incidence of disabling stroke or death in the short term.

Image: PD

©2025 2 Minute Medicine, Inc. All rights reserved. No works may be reproduced without expressed written consent from 2 Minute Medicine, Inc. Inquire about licensing here. No article should be construed as medical advice and is not intended as such by the authors or by 2 Minute Medicine, Inc.