High Resolution Mapping Of Cortical Blood Flow By Masaicing The Laser Speckle Images

High resolution blood vascular images are considerably important in many respects. Laser speckle imaging (LSI) has high spatial-temporal resolution and is noninvasive. Besides, LSI provides both morphological and velocity information in real time. So we used LSI to image the cortical blood flow of the mouse in this paper.LSI has been used to investigate the skin capillary flow, retinal flow and cerebral blood flow (CBF). But there are still some problems. The theoretical value of laser speckle contrast analysis (LASCA) should be within [0, 1], in practice, the contrast data are usually limited in an extremely low range. We used an enhanced laser speckle contrast analysis (eLASCA) to solve this problem.Besides, LSI usually monitors CBF only in a limited cortical area. Sometimes, we need a full view of global blood flow information across the cortex, e.g. finding the location of focus, the diagnosis and therapies of some cardiovascular diseases, helping surgeon during the surgery. While in practice, only a limited field of view is available when the image is acquired through a microscope. In this paper, we used image mosaicing technique to provide a high resolution full view of the cortical vascular blood flow information.In this study, the skull of mice was intact during the experiments. So we could monitor the long-term CBF changes in the same animal. Besides, the eLASCA-based LSI mosaicing provides global anatomic details of cortical microvessels as well as the cortical vascular blood flow information. Such a high resolution CBF mapping would also be potentially useful in neuroscience study.