Imaging hemodynamic response after distal middle cerebral artery occlusion with combined laser speckle imaging and visible-light optical coherence tomography

Abstract

Monitoring hemodynamic responses in the rodent stroke model is important in the study of ischemic stroke. However, it is hard for a single imaging modality to comprehensively explore these changes. In this study, we implemented laser speckle imaging (LSI) and visible-light optical coherence tomography (Vis-OCT) to detect cerebral blood flow (CBF), angiography and oxygen saturation (sO 2 ) in the mouse model of distal middle cerebral artery occlusion (dMCAO). LSI provides full-field, real-time cerebral blood flow (CBF) map to guide the Vis-OCT imaging. Vis-OCT offers angiography and sO 2 measurements. The results showed the detailed CBF and vasculature changes before and after dMCAO. After dMCAO, sO 2 changed little in arteries and arterioles, while sO 2 decreased in veins and venules. We also showed that larger veins had a higher decrease in sO 2 value in consecutive vein branches after dMCAO. It is suggested that the combination of LSI/Vis-OCT provides a promising tool for the rodent stroke model study.