High resolution mapping of cortical blood flow by mosaicing the laser speckle images

Laser speckle imaging (LSI) has been implemented as a tool of acquiring two dimensional blood flow information. Using vascular segmentation techniques, we are able to obtain the cortical vascular blood flow distribution. Nevertheless, the conventional LSI methods have limitations of small imaging area and low dynamic range of contrast due to the ambient background field, dark current and anomalies in the circuits of CCD camera. In this study, we introduced an enhanced laser speckle contrast analysis (eLASCA) to improve the dynamic range of LASCA, then a high resolution of cerebral blood flow (CBF) was obtained by image mosaicing technique, including image registration and image fusion. The eLASCA-based LSI mosaicing provides global anatomic details of cortical microvessels as well as the cortical vascular blood flow information.