Historical collection · First published Nov 20, 2024; added to EM Weekly Oct 27, 2026. This retrospective summary may be superseded by later evidence or guidance.
← All articlesMiddle Meningeal Artery Embolization for Nonacute Subdural Hematoma
Summary
MAGIC-MT randomized 722 patients in China with symptomatic nonacute subdural hematoma and mass effect to middle meningeal artery embolization or usual care after the treatment plan had been assigned to burr-hole drainage or nonsurgical management. The 90-day primary outcome of symptomatic recurrence or progression was 6.7% with embolization versus 9.9% with usual care (difference -3.3 percentage points, 95% CI -7.4 to 0.8; P=0.10), so the primary efficacy endpoint was not significantly improved. Serious adverse events were lower in the embolization group (6.7% vs 11.6%; P=0.02).
Why it matters
This large trial tempers a blanket assumption that MMA embolization improves all clinically important outcomes in nonacute subdural hematoma. ED disposition still centers on clinical status and neurosurgical evaluation; embolization is a downstream selected-patient strategy rather than a universal addition.
Study at a glance
- Design
- Randomized trial
- Population
- Adults with symptomatic nonacute subdural hematoma producing mass effect; patients requiring craniotomy or emergency hematoma evacuation were excluded.
- Sample size
- 722
- Intervention
- Middle meningeal artery embolization with liquid embolic material added to the preselected surgical or nonsurgical management strategy.
- Comparator
- Usual care with the preselected surgical or nonsurgical management strategy.
- Primary endpoint
- Symptomatic recurrence or progression of subdural hematoma within 90 days after randomization.
Main findings
- Symptomatic recurrence or progression at 90 days was 6.7% with embolization versus 9.9% with usual care (difference -3.3 percentage points, 95% CI -7.4 to 0.8; P=0.10).
- The primary efficacy endpoint therefore did not show a statistically significant benefit.
- Serious adverse events occurred in 6.7% versus 11.6% (P=0.02), a secondary safety finding.
- Burr-hole drainage was performed in 78.3% of participants and occurred after embolization in 99.6% of those undergoing drainage.
Limitations
The primary efficacy endpoint was not statistically significant, and the lower serious-adverse-event rate was a secondary safety result. The trial was open-label, conducted in China, excluded patients requiring craniotomy or emergency evacuation, and 78.3% underwent burr-hole drainage, limiting generalization to other subdural populations.
Read the primary source
Full text: Abstract available; full text paywalled.
Original sourcePMID: 39565989
Material reviewed: abstract.
Source retrieved Oct 27, 2026. NEJM publisher metadata verifies publication online on 2024-11-20; PubMed verifies DOI 10.1056/NEJMoa2401201 and PMID 39565989. The publisher abstract and PubMed abstract were reviewed; the full article was not reviewed end-to-end. This negative primary efficacy result is important context for the simultaneously published positive EMBOLISE and STEM trials and for later MMA embolization guidance. No retraction was identified in the targeted cross-check.
Corrections & review history
No corrections recorded. Human review: not yet human-reviewed.