Abstract Number ‐ 104: Outcomes after middle meningeal artery embolization using n‐butyl‐2 cyanoacrylate for subdural hematomas: a case‐series
Authors: Carrion‐Penagos Julian , Carrion‐Penagos Julian , Morsi Rami Z , Tarabichi Ammar , Thind Sonam , Kothari Sachin , Desai Harsh , Coleman Elisheva R , Brorson James R , Mendelson Scott J , Kramer Christopher , Goldenberg Fernando , Prabhakaran Shyam , Mansour Ali , Kass‐Hout Tareq 
Published: April 2023

Introduction
Chronic subdural hematomas (SDH) have a higher prevalence among the elderly population and can cause significant morbidity and mortality when they recur after surgical intervention. Use of n‐butyl‐2‐cyanoacrylate (n‐BCA) has proven to be an effective and safe therapeutic agent for embolization of the middle meningeal artery (MMA). In our study, we present a retrospective analysis of 31 patients who underwent MMA embolization for chronic SDH.

Methods
In a prospectively maintained database in a single center, we retrospectively analyzed 31 patients admitted to our institution who were diagnosed with chronic SDH, acute on chronic SDH, and acute SDH, and underwent MMA embolization with n‐BCA between May 20th, 2021, and June 28th, 2022. Our primary endpoint was >50% SDH reduction on follow‐up imaging. Our secondary endpoint was all‐cause mortality. Patients were separated into outcome groups and their baseline demographic, clinical, and procedural variables were compared using t‐test, Wilcoxon rank‐sum test, chi‐squared test, and Fisher’s exact test. Through univariate logistic regression, we attempted to determine if these variables directly influenced SDH reduction and mortality.

Results
In our study, a total of 42 MMA embolizations for 31 patients were included. We found that a greater number of patients with hypertension (n = 23; p = 0.04), use of antiplatelet (AP) medication (n = 8; p = 0.02), and those who underwent MMA embolization via the radial approach (n = 18; p = 0.004) were among those with < 50% SDH reduction. We also found that MMA embolization via the femoral approach (n = 13; p = 0.004) were more likely seen in those with >50% SDH reduction. The mean fluoroscopy time was longer in patients with >50% SDH reduction compared to those with < 50% reduction (43.2 minutes vs. 28.2 minutes, respectively; p = 0.03). On linear regression analysis, history of hypertension showed a non‐significant trend towards < 50% resolution of SDH (OR 5.67; 95% CI 0.99, 32.43; p = 0.05). Femoral approach for MMA embolization was associated with >50% of hematoma reduction (OR 12.00; 95% CI 1.89, 76.38; p = 0.004). Longer fluoroscopy time showed the same association (OR 1.05, 95% CI 1.00, 1.11; p = 0.03). All‐cause mortality was seen in 6 of the 31 patients, none of them associated with the SDH or the n‐BCA embolization procedure with no significant difference between groups.

Conclusions
MMA embolization with n‐BCA appears to be an effective and safe method for management of SDH as has been shown in prior retrospective studies. Our small sample size may underestimate the effect some variables have on radiographic and clinical outcomes. Hypertension and use of AP seem to play a role in hematoma resolution; however, a bigger cohort is needed to confirm these hypotheses. Femoral approach and longer fluoroscopy time were associated with hematoma resolution, but other variables should be considered to rule out any procedure‐related confounders. Future randomized controlled trials may help establish MMA embolization as the primary method for SDH management given its safety and morbidity compared to traditional methods of SDH evacuation.