Assessment of Recanalization after Intra-Arterial Thrombolysis in Patients with Acute Ischemic Stroke : Proposed Modification of the Qureshi Grading System

OBJECTIVE: We aimed to investigate the correlation between the success of recanalization and a modified version of the Qureshi grading system in acute ischemic stroke patients. METHODS: We retrospectively analyzed the intra-arterial thrombolysis (IAT) records of 37 patients who were evaluated by Thrombolysis in Myocardial Infarction (TIMI) and a modified version of the Qureshi grading systems as follows : 1) post-IAT Qureshi grade, 2) modified Δ Qureshi grade : pre-IAT group grade - post-IAT group grade (grade 1 : Qureshi grades 0-2 and grade 2 : Qureshi grade 3-5) and 3) Δ Qureshi grade (post-IAT Qureshi grade - pre-IAT Qureshi grade). Successful recanalization was defined as follows : 1) post-IAT TIMI grades 2 and 3, 2) post-IAT Qureshi grade 0-2, 3) modified Δ Qureshi grade=1, and 4) Δ Qureshi grade of ≥2 and/or post-IAT Qureshi grade=0. We investigated the correlation between the post-IAT TIMI grade and the modified Qureshi grade and also compared the various grading systems with modified Rankin Scale scores for evaluating the clinical outcome at 3 months. RESULTS: The post-IAT Qureshi grade and Δ Qureshi grade and/or post-IAT Qureshi grade were significantly correlated with the TIMI grade (γ=0.976 and, 0.942, respectively). Further, post-IAT Qureshi grade and Δ Qureshi grade and/or post-IAT Qureshi grade showed a significantly stronger association with clinical outcome than did the post-IAT TIMI grade (p=0.001 and, 0.000 vs. 0.083, respectively). CONCLUSION: Our preliminary results suggest that the modified Qureshi grading system is a useful tool for assessing the success of recanalization after IAT.