Abstract WP56: Volume of Contrast Staining After Intra-arterial Thrombectomy is Predictive of Stroke Volume

Introduction: Intra-arterial thrombectomy (IAT) has become the standard of care for large vessel ischemic stroke. Contrast staining seen on CT scan (CT-CS) obtained immediately after IAT has been well described as a result of contrast leakage/ extravasation into the brain parenchyma. Imaging typically shows deep contrast staining (DCS) or cortical contrast staining (CCS). There is very little data describing the relationship between DCS, CCS, and final MRI DWI stroke volume (DWI-SV). Hypothesis: Immediate post-IAT contrast staining on noncontrast CT head can predict final DWI-SV Methods: Charts were reviewed for sixty-five patients who underwent IAT between 07/01/10 and 06/30/15. Thirty-six subjects with immediate post-IAT CT, and MRI were included in the analysis. Patients were categorized into subgroups according to CT-CS: 1) absent CT-CS (n=4); 2) present CCS (n=27); 3) present DCS/absent CCS (n=5); Pearson correlation was used to evaluate the association between CT-CS and final DWI-SV. Results: Mean age was 66.5±14.28 (41% female, 58% male; 44% Caucasian, 11% African-American, 25% Hispanic and 19% Asian). Infarct territories included MCA (85%), ICA (11%), and basilar artery (3%). In the entire cohort, total contrast volume was associated with final DWI-SV (R 2 = 0.5045); There was significant correlation between CCS and final DWI-SV (R2 = 0.87236, P 2 = 0.36547). . Absence of contrast staining does not translate to absence of stroke. Conclusions: Cortical contrast staining on immediate post-IAT noncontrast CT head can reliably predict final DWI stroke volume