{
  "abstract": "Introduction/Purpose Subdural hematomas (SDH) commonly result from acceleration-deceleration forces causing bridging vein injury, followed by an inflammatory response and formation of outer and inner membranes with fragile neocapillaries, leading to hematoma expansion. A much rarer cause of traumatic SDH is intradural traumatic aneurysm rupture, particularly in the absence of subarachnoid hemorrhage. Cerebral aneurysms more commonly manifest as subarachnoid hemorrhage, which prompts further investigation leading to discovery of vascular anomalies. These two case reports from our institution highlight traumatic pseudoaneurysms causing subdural hematoma without subarachnoid hemorrhage.Materials and Methods Two patients with SDHs underwent middle meningeal embolization (MMAE). During diagnostic cerebral angiogram, distal middle cerebral artery (MCA) aneurysms were discovered within the vicinity of the subdural hematomas. Clinical, imaging, and treatment modalities were reviewed.Results Case 1: A 69-year-old male with history of prior left 5 mm subdural hematoma after ground-level fall and alcoholic cirrhosis presented after another ground level fall. CT head without contrast revealed a mixed density bilateral subdural hematoma. The patient did not require surgical evacuation and was referred for MMAE. Prior to the procedure, the patient had a brief worsening in his neurologic exam thus prompting a repeated CTH, which revealed an interval larger acute component to the SDH. CTA head with contrast demonstrated no vascular anomalies. During the MMAE procedure, a 3.5 mm left MCA aneurysm arising from the M4 segment was identified within the acute component of the SDH. Bilateral MMAE along with embolization of the aneurysm were achieved with Onyx (Medtronic, Irvine, CA, USA). Postoperatively, the patient recovered with no new neurological deficits.Case 2: An 87-year-old female with prior history of dementia presented with headache and dizziness after a ground-level fall. Non-contrast CT head revealed a 10 mm mixed density left sided subdural hematoma with a prominent acute component. Initially, she did not require surgical evacuation. She underwent left sided MMAE with N-butyl cyanoacrylate (NBCA) glue. Dedicated internal carotid artery runs obtained pre- and post-embolization revealed a 4.3 mm left MCA aneurysm arising from the M4 segment. MRI brain did not show a subarachnoid bleed. Due to the feasibility of the surgical approach with the superficially located aneurysm and the plan to perform surgical evacuation of the hematoma, she underwent open surgical treatment. Upon manipulation of the dura, there was active bleeding from the aneurysm. Parent M4 vessel sacrifice was performed with clipping. The patient did not have any additional neurological deficits following treatment.Conclusion These cases illustrate a rare etiology for subdural hematomas. Intradural peripheral MCA aneurysms can present with spontaneous SDHs even in the absence of subarachnoid hemorrhage. Recognition of this correlation is important for early intervention and prevention of rebleeding. Additionally, these cases serve as a comparison of endovascular versus surgical approach for management. It highlights the feasibility of both approaches and their safety when addressing such aneurysms. There currently is a gap in literature regarding standardized management of traumatic pseudoaneurysms.Disclosures H. Malik: None. S. Bagdadi: None. Y. Radaideh: None. D. Qaryouti: None.",
  "authors": [
    {
      "affiliations": [
        "Neurology, University of Florida – Jacksonville, Jacksonville, FL"
      ],
      "name": "H Malik"
    },
    {
      "affiliations": [
        "Neurology, University of Florida – Jacksonville, Jacksonville, FL"
      ],
      "name": "S Bagdadi"
    },
    {
      "affiliations": [
        "Neurology, University of Florida – Jacksonville, Jacksonville, FL"
      ],
      "name": "Y Radaideh"
    },
    {
      "affiliations": [
        "Neurology, University of Florida – Jacksonville, Jacksonville, FL"
      ],
      "name": "D Qaryouti"
    }
  ],
  "title": "E-246 Beyond bridging veins: traumatic intradural pseudoaneurysms as an underrecognized cause of isolated subdural hematoma",
  "uid": "bd4a2024-5882-5ba3-b548-68cd802bc917"
}