Effect of Thinned-Skull Cranial Window on Monitoring Cerebral Blood Flow Using Laser Speckle Contrast Imaging

Studies on laboratory animals are a crucial step in a wide range of fundamental and applied scientific investigations. In addition to ensuring that research methods are chosen correctly, it is also necessary to use them properly in order to obtain the maximum amount of reliable information. In this study, we analyze and compare laser speckle contrast imaging (LSCI) data obtained simultaneously from the intact skull area and from the thinned skull area of the young laboratory rat (1.5-months-old), while additionally introducing a physiological challenge in the form of blood loss. We describe the experimental setup and materials used and also outline the signal processing approach. Finally, we present the results obtained and provide a discussion comparing our findings with studies conducted by other researchers, as well as addressing both the highlights and limitations of the study. In summary, the investigations conducted indicate that a cranial preparation is needed to record reliable LSCI data for cerebral perfusion, and it is also found that moderate blood loss does not reduce cerebral blood flow to the level of its autoregulation impairment.