ABSTRACT NUMBER: ESOC2026A576 INCOMPLETE REPERFUSION ON FLAT-PANEL CT-AUGMENTED REPERFUSION GRADING IS ASSOCIATED WITH LARGER INFARCT VOLUME AFTER THROMBECTOMY

Abstract Background and aims Distal occlusion tracker (DOT) signs on immediate post-interventional flat-panel detector CT (FDCT) may help identify residual vessel occlusions and reduce overestimation of reperfusion after endovascular therapy (EVT). We investigated the association between FDCT-augmented reperfusion grading and tissue imaging outcomes after EVT. Methods We retrospectively analyzed EVT-treated patients achieving expanded thrombolysis in cerebral infarction (eTICI) ≥2b who had post-MT FDCT and follow-up MRI. The DOT sign was defined as punctiform or tubular hyperdensities on FDCT. Final infarct volume (FIV) was manually segmented on follow-up diffusion-weighted imaging. Reperfusion status was categorized as incomplete (eTICI 2b) or near-complete (eTICI 2c/3) based on either FDCT-augmented TICI, assessed by a core laboratory, or operator-graded TICI. Results Among 176 patients, 61 (34.7%) had incomplete and 115 (65.3%) had near-complete reperfusion according to FDCT-augmented TICI. Of cases classified as near-complete by operator-graded TICI, 13 were reclassified as incomplete on FDCT-augmented TICI; conversely, three cases deemed incomplete by operators were assessed as near-complete with FDCT-augmented TICI. Incomplete reperfusion was significantly associated with larger FIV compared with near-complete reperfusion (39.8 vs. 14.9 mL; β=32.4 mL, 95% CI 9.8–55.0). Incomplete reperfusion defined by FDCT-augmented TICI showed a directionally stronger association with FIV compared with operator-graded TICI (β=22.8 mL, 95% CI −1.9–47.4), although the bootstrap-estimated difference in coefficients was not statistically significant (Δβ=49.3 mL, 95% CI −14.5–114.3; P=0.16). Conclusions Incomplete reperfusion assessed by FDCT-augmented TICI was associated with larger infarct volumes compared with near-complete reperfusion, suggesting that adjunctive FDCT may improve tissue-level assessment after EVT. Conflict of interest All of authors. nothing to disclose.