{'fraction_non_alphanumeric': 0.03581267217630854, 'fraction_numerical': 0.024793388429752067, 'mean_word_length': 5.154661016949152, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 1, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
O-020 A comparison of infarct volumes in patients with large vessel occlusions based on treatment modality: a retrospective analysis

Introduction Intra-arterial (IA) therapy for large vessel occlusions (LVO) results in higher recanalization rates compared to intravenous (IV) thrombolysis. Recanalization after LVO is also a predictor of better clinical outcome. Whether IA therapy results in lower stroke infarct burden has not previously been determined. Infarct volume has been shown to have a strong correlation to 90-day clinical outcome. We hypothesized that patients treated with IA therapy will have lower post-procedure infarct volumes compared to IV thrombolysis or untreated patients. Materials and methods A retrospective chart review was performed on consecutive patients with LVO between November 2010 and December 2011 at Emory University Hospital and Grady Memorial Hospital. LVO was defined as extracranial/intracranial internal carotid artery (ICA), M1 middle cerebral artery (MCA) or M2 MCA occlusions identified by CT, MR or conventional angiography. Adults (>18 years) with LVO who presented within 8 h from time last seen normal were included and grouped as follows: those receiving intra-arterial/endovascular therapy (IA group), intravenous thrombolysis only (IV group) and no thrombolysis (Untreated group). Baseline characteristics were recorded on all patients. Infarct volume was measured using subsequent CT or MRI imaging after the first 24 h and compared using the Mann–Whitney U test. Data are represented as box plots showing the median infarct volume and the first and third IQRs for each group (Abstract O-020 figure 1A,B).Abstract O-020 Figure 1 (A) Infarct Volumes in LVO. (B) Infarct volume based on location of occlusion and treatment modality. Results 192 patients with LVO met inclusion criteria (IA: 127 patients, IV: 35 patients, Untreated: 30 patients). The mean age for the entire cohort was 66±16 years and the mean NIHSS was 19±6. Baseline clinical characteristics were comparable between the three groups. In all LVOs, median infarct volume was significantly smaller in the IA group compared to the untreated group (Abstract O-020 figure 1A, p=0.02) while infarct volume in the untreated and IV groups was similar (p=0.8). Based on level of occlusion, infarct volume was significantly smaller in the IA group compared to the untreated/IV group (Abstract O-020 figure 1B) in patients with terminal ICA (ICA-T) (p=0.005) and M1 MCA occlusions (p=0.02). Infarct volume in M2 occlusions was similar between the groups (p=0.3). Conclusions Endovascular therapy for anterior circulation LVO appears to reduce infarct volumes in patients presenting within 8 h from symptom onset especially in ICA-T and M1 occlusions but not M2 occlusions. Prospective studies are needed to replicate these findings and correlate with clinical outcomes. Competing interests None.