{
  "abstract": "Introduction/Purpose Middle meningeal artery embolization (MMAE) has emerged as a promising intervention for mitigating chronic subdural hematoma (cSDH) progression and recurrence by reducing the vascular supply to inflamed dural membranes. Recently, several randomized clinical trials such as EMBOLISE provided data on MMAE efficacy. There is ongoing debate about the embolization target, specifically on how distal the liquid embolic material (e.g. Onyx LES, Medtronic) should be positioned to optimize the treatment effect. This study evaluates the association between the spatial distribution of Onyx and the degree of hematoma resolution.Materials and Methods We used the Geometric Hierarchical Opacification Scoring of MMA Embolization Therapy (GHOST) methodology to systematically assess the distribution of Onyx LES following MMAE. The score evaluates embolic penetration across 18 predefined anatomical locations. First, Onyx distribution was analyzed on unsubtracted angiographic images (GHOST-2D, figure 1a). Second, the same scoring framework was applied to reconstructed CT images (GHOST-3D, figure 1b), enabling improved visualization of distal embolic penetration. Associations between the geometric distribution of Onyx and hematoma resolution were analyzed. This study is a post-hoc analysis of EMBOLISE (NCT04402632; Medtronic sponsored), a multicenter RCT that enrolled 400 participants in whom surgical evacuation was indicated as primary cSDH treatment. Standard imaging analyses including the manual hematoma segmentations and volumetric assessment were conducted by an independent core laboratory (Eppdata, Hamburg, Germany).Results This post-hoc analysis is ongoing at the time of this writing. We initiated by analyzing the quartiles in the hematoma resolution (spectrum: from most pronounced volume decreases to smallest volume decreases and recurrences). Based on the known distribution of hematoma volume changes, we expect sufficient power for detecting an effect for the association between embolization distality and hematoma resolution. Furthermore, we will present the spatial relationship between Onyx LES distribution and hematoma location, and compare insights obtained from angiographic (2D) versus CT-based (3D) assessment.Conclusion This post-hoc analysis of the EMBOLISE RCT systematically investigates the influence of distality of Onyx LES penetration on the treatment effect in cSDH therapy. The EMBOLISE trial, including the RCT control group, provides a robust dataset for this analysis. Results to be presented at SNIS.Disclosures H. Kniep: 2; C; Eppdata. 4; C; Eppdata. Y. Gonzalez: 5; C; Eppdata. L. Meucci: None. M. Maros: 2; C; Eppdata. J. Fiehler: 1; C; Medtronic. 2; C; Medtronic. 4; C; Eppdata, Vastrax. 5; C; Eppdata.Abstract E-134 Figure 1",
  "authors": [
    {
      "affiliations": [
        "Neuroradiology, UMC Hamburg-Eppendorf, Hamburg, Germany"
      ],
      "name": "H Kniep"
    },
    {
      "affiliations": [
        "Eppdata, Hamburg, Germany"
      ],
      "name": "Y Gonzalez"
    },
    {
      "affiliations": [
        "Neuroradiology, UMC Hamburg-Eppendorf, Hamburg, Germany"
      ],
      "name": "L Meucci"
    },
    {
      "affiliations": [
        "University at Buffalo, Buffalo, NY"
      ],
      "name": "J Knopman"
    },
    {
      "affiliations": [
        "University at Buffalo, Buffalo, NY"
      ],
      "name": "JM Davies"
    },
    {
      "affiliations": [
        "University at Buffalo, Buffalo, NY"
      ],
      "name": "M Mokin"
    },
    {
      "affiliations": [
        "University of Buffalo, Buffalo, NY"
      ],
      "name": "A Siddiqui"
    },
    {
      "affiliations": [
        "Neuroradiology, UMC Mannheim, Mannheim, Germany"
      ],
      "name": "M Maros"
    },
    {
      "affiliations": [
        "Neuroradiology, UMC Hamburg-Eppendorf, Hamburg, Germany"
      ],
      "name": "J Fiehler"
    }
  ],
  "title": "E-134 Association of onyx distribution and degree of hematoma reduction in the EMBOLISE study",
  "uid": "72418eca-4133-56e6-8726-bee95b9994e1"
}