{
  "abstract": "Background Middle meningeal artery embolization (MMAE) has emerged as a disease-modifying therapy for chronic subdural hematoma (cSDH), yet the comparative effectiveness of embolic agents remains uncertain. We performed a comprehensive meta-analysis to evaluate clinical, radiological, safety, and economic outcomes across embolic strategies.Methods We conducted a PRISMA-compliant systematic review of randomized and observational studies evaluating MMAE for cSDH through October 2025. The primary outcome was recurrence/progression. Secondary outcomes included surgical rescue, radiological response, functional outcome, mortality, complications, and cost. Random-effects models were applied, with prespecified subgroup analyses by embolic agent and treatment strategy (primary vs adjuvant).Results Sixty-eight cohorts encompassing 5,574 patients and 6,260 procedures were included. The pooled recurrence/progression rate was 6.8% (95% CI, 6.0-8.0%; I 2 = 17.9%), without significant differences across embolic agents (p = 0.72) or embolic class (particles 7.0% vs liquid agents 6.6%; p = 0.76). Recurrence was similar between primary and adjuvant MMAE (7.0% vs 6.0%; p = 0.43). Surgical rescue occurred in 6.0% (95% CI, 5.0-7.0%; I2 = 7.3%). This was the only outcome demonstrating a significant subgroup difference: rescue was higher following primary compared with adjuvant MMAE (7.8% vs 4.1%; p = 0.0097). No significant differences in surgical rescue were observed across embolic agents or classes (p = 0.60). Favorable radiological outcomes occurred in 86% (95% CI, 79-91%), and stable/improved functional status in 94% (95% CI, 91-96%), without differences between embolic materials. The pooled complication rate was 3.0% (95% CI, 2-5%), and mortality was 1.06% (95% CI, 0.57-1.98%), with no significant class-level differences. Economic data, though limited, consistently demonstrated lower per-procedure material costs for particle-based embolization compared with liquid embolics, without evidence of outcome superiority for higher-cost agents.Conclusions Across more than 6,000 procedures, embolic agents demonstrated comparable efficacy and safety profiles in MMAE for cSDH. Surgical rescue was lower when MMAE was performed as an adjuvant strategy. In the absence of demonstrated clinical superiority, embolic selection may reasonably prioritize anatomical considerations and cost, supporting scalable adoption as cSDH incidence rises globally.Disclosures N. Vasconcellos de Oliveira Souza: None. A. Hamouda: None. A. Khalid Abdallah: None. M. Seifuldin: None. F. Atieh: None. R. Hamdy: None. S. Hossameldin: None. R. Kadrivel: None.Abstract O-024 Figure 1",
  "authors": [
    {
      "affiliations": [
        "Neurology, Thomas Jefferson University Hospital, Philadelphia, PA"
      ],
      "name": "N Vasconcellos de Oliveira Souza"
    },
    {
      "affiliations": [
        "Neurosurgery, Mayo Clinic Rochester, Rochester, MN"
      ],
      "name": "A Hamouda"
    },
    {
      "affiliations": [
        "Neurology, Faculty of Medicine, Menofia University, Menofia, Egypt, Menofia Governorate, Egypt"
      ],
      "name": "A Khalid Abdallah"
    },
    {
      "affiliations": [
        "Medicine, College of Medicine, Alfaisal University, Riyadh, Saudi Arabia, Riyadh, Saudi arabia"
      ],
      "name": "M Seifuldin"
    },
    {
      "affiliations": [
        "Medicine, School of Medicine, Royal College of Surgeons in Ireland, Bahrain, Bahrain, AL"
      ],
      "name": "F Atieh"
    },
    {
      "affiliations": [
        "Medicine, Faculty of medicine, Tanta university, Egypt, Tanta QISM /First Tanta, Egypt"
      ],
      "name": "R Hamdy"
    },
    {
      "affiliations": [
        "Neurology, Yale University School of Medicine, New Haven, CT"
      ],
      "name": "S Hossameldin"
    },
    {
      "affiliations": [
        "Mayo Clinic, Rochester, MN"
      ],
      "name": "S Ghozy"
    },
    {
      "affiliations": [
        "Radiology, Mayo Clinic, Rochester, MN"
      ],
      "name": "W Brinjikji"
    },
    {
      "affiliations": [
        "Neurosurgery, Mayo Clinic Rochester, Rochester, MN"
      ],
      "name": "R Kadrivel"
    },
    {
      "affiliations": [
        "Radiology, Mayo Clinic, Rochester, MN"
      ],
      "name": "D Kallmes"
    },
    {
      "affiliations": [
        "Thomas Jefferson University Hospital, Philadelphia, PA"
      ],
      "name": "P Jabbour"
    }
  ],
  "title": "O-024 Comparative effectiveness of embolic agents in middle meningeal artery embolization for chronic subdural hematoma: a systematic review and meta-analysis",
  "uid": "b8b4e7c0-5c4d-5bbc-9a05-b45627f34ca1"
}