Monitoring capillary blood flow using laser speckle contrast analysis with spatial and temporal statistics

Laser Speckle Contrast Imaging (LSCI) is a simple and powerful technique that is used for full-field imaging of blood flow. The technique analyzes fluctuations in a dynamic speckle pattern to detect the movement of particles. In this article Laser speckle contrast analysis based on spatial and temporal correlations (sLASCA and tLASCA) were used to provide a velocity map of the area of interest in real time without the need for scanning. Spatial and temporal laser speckle contrast analysis have been shown to be a viable real-time method for detecting variations in blood flow. The results of some initial experiments on volunteers are presented. Both the techniques namely sLASCA and tLASCA are able to pick up changes in blood flow, which may arise due to various physiological conditions. Further, more blood flow reflected due to less skin thickness was sensed by the tLASCA technique which can be put to good use in the follow-up of the treatment of certain diseases which may cause decreased blood flow. Thus, both the techniques can be used to compare differences in blood flow values at region in normal subjects and in diseased subjects.