Comparison of Laser Speckle Contrast Imaging and Laser Doppler Imaging

The microcirculation plays a fundamental role in metabolic reactions and has been shown as an essential determinant in many clinical scenarios such as shock states, chronic and cardio-metabolic diseases. Microcirculation can be assessed directly using laser-based techniques and intravital microscopes. When combined with provocation tests, microvascular monitorization can be used to assess microvascular function. Laser-based techniques are consist of two different methods named laser doppler imaging (LDI), laser speckle contrast imaging (LSCI). LSCI is a technique based on speckle contrast analysis that provides an index of blood flux. No need for skin contact, continuous and real-time assessment of the microcirculation led the LSCI to be broadly used in clinical practice. LDI is also a non-invasive diagnostic method used to measure the blood flux of tissue. The technique is based on measuring the doppler shift induced by moving red blood cells to the illuminating coherent light. Iontophoresis is one of the most commonly used provocation tests to study the endothelium in terms of endothelium-dependent and endothelium-independent vasodilation. Simultaneously with LDI and LSCI are used to follow and assess the skin blood flux during iontophoresis. Therefore, it provides a state to make a comparison between two different laser-based techniques in terms of flux characteristics. The accurate assessment of burn depth is a critical step in the management of the burn-injured patient. Currently, LDI is the most widely used non-invasive measurement tool for assessing burn wounds and the only technique approved by the U.S. Food and Drug Administration. However, the LDI device is rather costly, cumbersome, and has a poor spatial resolution. LSCI measures perfusion in a similar way, but it provides high-quality images with a much higher spatial resolution. In addition, LSCI is much quicker, maneuverable, and able to assess larger skin areas. In order to use the LSCI technique i