Spatiotemporal changes of cerebral blood flow following hemorrhagic stroke by laser speckle imaging

Hemorrhagic stroke accounts for more than 15% of all stroke hospitalization with much higher mortality than ischemic stroke. In this study, we investigated the spatiotemporal changes of the cerebral blood flow (CBF) following intracerebral hemorrhagic (ICH) stroke by laser speckle imaging. Adult male C57BL/6 mice were divided into ICH group (n=7) and saline group (n=4). CBF images were recorded before injury, 30 minutes, 24, 48, and 72 hours after stroke. Results showed that both ipsilateral CBF and contralateral CBF significantly reduced in two groups, which suggested that the mass effect was the dominant factor in the early stage of hemorrhagic brain injury. In ICH group, although the lesion was mainly around the injection location at first, hematoma could last for a long period of time and cause a secondary brain injury. The preliminary results showed that laser speckle imaging demonstrated its reliability with high spatiotemporal resolution in imaging mouse CBF with hemorrhagic stroke.