To do or not to do; dilemma of intra-arterial revascularization in acute ischemic stroke

Background: There has still been lack of evidence for definite imaging criteria of intra-arterial revascularization (IAR). Therefore, IAR selection is left largely to individual clinicians. In this study, we sought to investigate the overall agreement of IAR selection among different stroke clinicians and factors associated with good agreement of IAR selection. Methods: From the prospectively registered data base of a tertiary hospital, we identified consecutive patients with acute ischemic stroke. IAR selection based on the provided magnetic resonance imaging (MRI) results and clinical information were independently performed by 5 independent stroke physicians currently working at 4 different university hospitals. MRI results were also reviewed by 2 independent experienced neurologists blinded to clinical data and physicians' IAR selection. The Alberta Stroke Program Early Computed Tomography Score (ASPECTS) was calculated on initial DWI and MTT. We arbitrarily used ASPECTS differences between DWI and MTT (D-M ASPECTS) to quantitatively evaluate mismatch. Results: The overall interobserver agreement of IAR selection was fair (kappa = 0.398). In patients with DWI-ASPECTS >6, interobserver agreement was moderate to substantial (0.398-0.620). In patients with D-M ASPECTS >4, interobserver agreement was moderate to almost perfect (0.532-1.000). Patients with higher DWI or D-M ASPECTS had better agreement of IAR selection. Conclusion: Our study showed that DWI-ASPSECTS >6 and D-M ASPECTS >4 had moderate to substantial agreement of IAR selection among different stroke physicians. However, there is still poor agreement as to whether IAR should not be performed in patients with lower DWI and D-M ASPECTS.