{
  "abstract": "Introduction Early follow-up after flow diversion may demonstrate neck remnants rather than complete aneurysm occlusion. While Raymond-Roy class I (RR1) is traditionally considered the optimal angiographic endpoint, the natural history and clinical significance of Raymond-Roy class II (RR2) remnants remain incompletely defined. In clinical practice, these findings often prompt retreatment despite limited evidence supporting this approach. We sought to evaluate the longitudinal evolution of RR2 aneurysms following flow diversion to determine whether these lesions remain stable or progress to complete occlusion over time.Methods An IRB-approved, prospectively maintained database of the senior author’s cases was retrospectively reviewed. Patients who underwent flow diversion with a 6-month follow-up angiogram demonstrating RR2 occlusion and at least one subsequent angiographic follow-up were included. Demographic, aneurysm, and outcome data were analyzed.Results From 2019 to 2025, 31 patients who underwent flow diversion procedures had at least two follow-up angiographies with the first angiography demonstrating RR 2. The average age was 63 ± 2.3 years, with 23 of them being female (74%). Average aneurysm size was 5.5 ± 0.7 mm with the most common vessel locations being internal carotid artery (22 cases, 71%) and anterior cerebellar artery (3 cases, 10%). Of the 31 patients, 19 patients (61%) with a RR 2 on 6-month followup had a RR1 on their last followup. There were 9 patients (29%) with a stable RR 2 score between the first and second followup angiographies. The remaining 3 patients (10%) had RR 3 on last followup. Importantly, no aneurysm ruptures occurred during the follow-up period.Conclusion RR2 aneurysms following flow diversion demonstrate a strong propensity for delayed progression to complete occlusion. These findings suggest that RR2 neck remnants represent a transitional, often self-resolving state rather than a failure of treatment. Routine early retreatment may therefore be unnecessary, and a strategy of continued observation is reasonable in appropriately selected patients.Disclosures J. Collard de Beaufort: None. J. Campos: 2; C; Rapid Medical. K. Van Orden: None. M. Arthur: None. B. Polis: None. J. Hamilton: None. D.A. Zarrin: None. F. Laghari: None. N. Beaty: 6; C; Medtronic Neurovascular, Stryker Neurovascular, CMO of NeuroMedica. G. Colby: 2; C; Medtronic Neurovascular, MicroVention-Terumo, Rapid Medical, Cerenovus, Stryker Neurovascular. A.L. Coon: 2; C; Medtronic Neurovascular, MicroVention-Terumo, Stryker Neurovascular, Cerenovus, Rapid Medical, Avail MedSystems, Imperative Care, Deinde, InNeuroCo, Q’apel. 6; C; MicroVention-Termo, Stryker Neurovascular, Medtronic Neurovascular.Abstract P-029 Figure 1Illustrative case of a 55-year old female with a 5mm left clinoidal aneurysm treated with a Surpass Evolve stent. Both 6- and 12-month followup demonstrate RR2, but 36-month followup demonstrates complete (RR1) occlusion of the aneurysm",
  "authors": [
    {
      "affiliations": [
        "SUNY Upstate Medical School, Syracuse, NY"
      ],
      "name": "J Collard de Beaufort"
    },
    {
      "affiliations": [
        "Department of Neurological Surgery, University of California, Irvine, Orange, CA"
      ],
      "name": "J Campos"
    },
    {
      "affiliations": [
        "St. Joseph’s Hospital, Carondelet Neurological Institute, Tucson, AZ"
      ],
      "name": "K Van Orden"
    },
    {
      "affiliations": [
        "St. Joseph’s Hospital, Carondelet Neurological Institute, Tucson, AZ"
      ],
      "name": "M Arthur"
    },
    {
      "affiliations": [
        "Syracuse University, Syracuse, NY"
      ],
      "name": "B Polis"
    },
    {
      "affiliations": [
        "Department of Neurological Surgery, University of California, Irvine, Orange, CA"
      ],
      "name": "J Hamilton"
    },
    {
      "affiliations": [
        "Neurosurgery, University of Arizona College of Medicine, Tucson, Tucson, AZ"
      ],
      "name": "B Meyer"
    },
    {
      "affiliations": [
        "Department of Neurosurgery, Johns Hopkins University, Baltimore, MD"
      ],
      "name": "DA Zarrin"
    },
    {
      "affiliations": [
        "St. Joseph’s Hospital, Carondelet Neurological Institute, Tucson, AZ"
      ],
      "name": "F Laghari"
    },
    {
      "affiliations": [
        "Tallahassee Memorial Hospital, Florida State University, Tallahassee, FL"
      ],
      "name": "N Beaty"
    },
    {
      "affiliations": [
        "Department of Neurological Surgery, University of California, Irvine, Los Angeles, CA"
      ],
      "name": "G Colby"
    },
    {
      "affiliations": [
        "St. Joseph’s Hospital, Carondelet Neurological Institute, Tucson, AZ"
      ],
      "name": "AL Coon"
    }
  ],
  "title": "P-029 Fate of Raymond-Roy Class II aneurysms after flow diversion: experience in 31 cases",
  "uid": "c21500a6-16a0-5176-b920-7a26a6437a2b"
}