{
  "abstract": "Introduction/Purpose Randomized trials failed to show benefit of endovascular treatment (EVT) in patients with distal/medium vessel occlusion (DMVO) over standard therapy. Vascular anatomical features may identify subgroups at great risk of harm and reduced recanalization success from EVT.Materials/Methods Patients with distal middle/anterior cerebral artery (MCA/ACA) occlusion from two centers who received EVT (2018-2025) were retrospectively included. Nine centerline-derived descriptors (including length, tortuosity index [TI], and diameter) of the MCA/ACA segment, i.e., from internal carotid artery bifurcation to occlusion site, were semi-automatically extracted from baseline CTA. The primary study endpoint was Failed EVT (eTICI 0/2B and/or SAH/PH2). TI was identified as the strongest predictor over the primary endpoint. TI’s overall effect on the primary endpoint was evaluated by fixed-effects linear regression, using the number of EVT passes (1 vs. >1) as an interaction variable. Ordinal regression evaluated impact over 90-day functional outcomes (mRS).Results The study sample comprised 248 patients (79 years IQR 70-86, 51.2% female; 2% proximal M2, 87.2% distal M2, 4.8% M3, 4.8% A2, 1.2% A3). Failed EVT occurred in 44% of cases; eTICI 2C/3 was achieved in 68.5% of interventions, while 23.4% of patients suffered SAH/PH2. In 43.5% of patients, multiple EVT passes were performed. TI (0.36, IQR 0.27-0.43) was associated with Failed EVT (OR per 0.1 TI increase 1.35 [95%CI 1.07-1.70], p=0.012). Interaction analysis showed a trend towards Failed EVT with higher TI in the multi-pass group (OR 1.59 [0.95-2.66], p=0.079), but no effect for 1-pass (OR 1.20 [0.89-1.62], p=0.220). Risk-benefit analysis identified patients with unfavorable anatomical profile at TI>0.40. TI was associated with worse mRS only when multiple passes were needed (1 pass: OR 0.95 [0.74-1.21], p=0.666; >1 pass: OR 1.76 [1.16-2.66], p=0.008). Patients with favorable anatomy (63.3%, 157/248) had comparable outcomes regardless of number of passes (OR 1.13 [0.65-1.98], p=0.659; 52% had mRS 0-2). Patients with unfavorable anatomy and one pass maintained similar outcomes (52% mRS 0-2), while worse outcomes were observed multiple passes were needed (OR 2.66 [1.11-4.54], p=0.011; 33% mRS 0-2).Conclusions In DMVO patients receiving EVT, TI is strongly associated with treatment failure beyond the first pass. Our findings suggest robust functional outcomes are achievable in patients with favorable anatomy, regardless of number of passes, and in patients with unfavorable anatomy who achieve first pass reperfusion. High risk of hemorrhage with diminishing probability of complete recanalization may hinder the effect of successive thrombectomy attempts in patients with high intracranial vascular tortuosity.Disclosures P. Canals: 1; C; AHA. 5; C; Stanford University. L. Fernández-Espigares: None. X. Li: None. M. Rodrigo-Gisbert: None. J. González-Riveros: None. J. Mayol: None. A. García-Tornel: 2; C; AptaTargets. M. Requena: 2; C; Philips, iVascular. A. Murillo-Olaizola: None. A. Tomasello: None. E. Zapata-Arriaza: None. F. Moniche: None. M. Ribo: None.Abstract E-352 Figure 1(A) Interaction plot, displaying the probability of Failed EVT (eTICI 0/2B and/or SAH/PH2) with increasing MCA/ACA TI, for patients who received one EVT pass (blue) and multiple passes (red). (B) Grotta bars showing the mRS distribution of patients with favorable/unfavorable anatomy who received one pass (top) and multiple passes (bottom). On the left, the prevalence for each endpoint (Failed EVT: black; eTICI 0/2B: blue; SAH/PH2: red) is shown for each group. EVT: endovascular treatment. MCA/ACA: middle/anterior cerebral artery. Tl: tortuosity index. SAH: sub-arachoid hemorrhage. PH2: parenchymal hematoma type 2",
  "authors": [
    {
      "affiliations": [
        "Radiology, Stanford University, Stanford, CA"
      ],
      "name": "P Canals"
    },
    {
      "affiliations": [
        "Neurology, Hospital Universitario Virgen del Rocío, Sevilla, Spain"
      ],
      "name": "L Fernández-Espigares"
    },
    {
      "affiliations": [
        "Neurology, Stanford University, Palo Alto, CA"
      ],
      "name": "X Li"
    },
    {
      "affiliations": [
        "Neuroradiology, Hospital Vall d’Hebron, Barcelona, Spain"
      ],
      "name": "M Rodrigo-Gisbert"
    },
    {
      "affiliations": [
        "Neurology, Hospital Vall d’Hebron, Barcelona, Spain"
      ],
      "name": "J González-Riveros"
    },
    {
      "affiliations": [
        "Neurology, Hospital Vall d’Hebron, Barcelona, Spain"
      ],
      "name": "J Mayol"
    },
    {
      "affiliations": [
        "Neurology, Hospital Vall d’Hebron, Barcelona, Spain"
      ],
      "name": "A García-Tornel"
    },
    {
      "affiliations": [
        "Neuroradiology, Hospital Vall d’Hebron, Barcelona, Spain"
      ],
      "name": "M Requena"
    },
    {
      "affiliations": [
        "Neurology, Hospital Vall d’Hebron, Barcelona, Spain"
      ],
      "name": "A Murillo-Olaizola"
    },
    {
      "affiliations": [
        "Neuroradiology, Hospital Vall d’Hebron, Barcelona, Spain"
      ],
      "name": "A Tomasello"
    },
    {
      "affiliations": [
        "Neuroradiology, Hospital Universitario Virgen del Rocío, Sevilla, Spain"
      ],
      "name": "E Zapata-Arriaza"
    },
    {
      "affiliations": [
        "Neuroradiology, Hospital Universitario Virgen del Rocío, Sevilla, Spain"
      ],
      "name": "F Moniche"
    },
    {
      "affiliations": [
        "Interventional Neuroradiology, Stanford University, Stanford, CA"
      ],
      "name": "J Heit"
    },
    {
      "affiliations": [
        "Neurology, Hospital Vall d’Hebron, Barcelona, Spain"
      ],
      "name": "M Ribo"
    }
  ],
  "title": "E-352 Intracranial vascular tortuosity predicts failed recanalization and hemorrhagic events in patients with a distal/medium vessel occlusion beyond one pass: a multicenter study",
  "uid": "5f083297-1133-5b75-b5e9-53baa587f921"
}