Timing of adjunctive middle meningeal artery embolization relative to surgical evacuation for chronic and subacute subdural hematomas

ABSTRACT

BACKGROUND AND PURPOSE:

Recent randomized trials have suggested that middle meningeal artery embolization (MMAE) is an effective treatment for preventing the recurrence of subacute and chronic subdural hematoma (SDH). As such, MMAE is increasingly being adopted as the standard of care worldwide, and it is projected to become the most common neuro-interventional procedure by 2029. While MMAE is an effective surgical adjunct, the optimal timing of MMAE relative to surgical evacuation remains unclear. This study evaluated whether the timing of MMAE influences clinical and healthcare utilization outcomes.

MATERIALS AND METHODS:

We conducted a retrospective cohort study using the 2019–2022 Nationwide Readmissions Database. Non-electively hospitalized SDH patients who received both surgical evacuation and MMAE were included. Patients were stratified into three groups based on MMAE timing: before, same-day (concurrent), or after surgery. Outcomes included discharge disposition, in-hospital complications and mortality, 180-day treatment failure and surgical rescue, hospitalization cost, and length of stay (LOS). Multivariable adjustments were made for baseline characteristics that were different between study groups (p<0.10).

RESULTS:

Of 1,518 patients, 325 (21.4%) received concurrent MMAE+surgery, 149 (9.8%) MMAE first, and 1,043 (68.7%) surgery first. There were no significant differences in discharge disposition, in-hospital complications, mortality, or 180-day outcomes across timing groups (all p>0.05). However, concurrent MMAE+surgery was associated with shorter LOS (median 5 days) compared to MMAE first (8 days, adjusted p<0.001) and surgery first (8 days, adjusted p<0.001). Moreover, concurrent MMAE+surgey was associated with significantly lower hospitalization costs (median 42,147 USD) compared to MMAE-first (53,536 USD, adjusted p=0.014) and surgery-first (median 53,941 USD, adjusted p<0.001).

CONCLUSIONS:

Clinical outcomes were comparable across timing strategies for MMAE as an adjunct to surgery. However, concurrent MMAE+surgery was associated with significantly reduced LOS and hospitalization costs, suggesting logistical and economic advantages for same-day treatment. ABBREVIATIONS: MMAE= middle meningeal artery embolization; SDH= subdural hematoma; LOS= length of stay.