Rapid Processing of Perfusion and Diffusion for Ischemic Strokes in the Extended Time Window: An Indian Experience

BACKGROUND: Endovascular treatment of acute ischemic stroke with large-vessel occlusion is the standard of care now. Initially restricted to 6 h after onset, the treatment can now be offered to selected patients up to 24 h based on clinical and imaging criteria. OBJECTIVE: Perfusion imaging can help in identifying patients who may benefit from endovascular treatment in the extended time window. Manual analysis of perfusion images is time and skill intensive. Rapid processing of perfusion and diffusion (RAPID) is an automated image analysis system that analyzes perfusion maps. We report our initial experience of using this system in selection of patients for endovascular stroke treatment. METHODS: All patients who presented with acute stroke underwent baseline imaging with computed tomography (CT) and CT angiogram or magnetic resonance imaging (MRI) and MR angiogram. Patients presenting between 6 and 24 h after onset underwent perfusion imaging, which was analyzed by RAPID. The results were used to select the patients who then underwent mechanical thrombectomy. RESULTS: RAPID results identifying ischemic core and hypoperfused tissue were available within 5 min in each of the three cases. At 3 months, all patients showed improvement in the modified Rankin Scale. CONCLUSION: In extended time windows, RAPID provides a fast and reliable estimate of salvageable brain tissue to help select patients for endovascular treatment.