Study On The Method Of Laparoscopic Laser Speckle Blood Flow Imaging

Laser speckle contrast imaging(LSCI)has the advantages of simple structure,high temporal and spatial resolution,fast speed,and real-time full-field imaging.It has great development potential in the blood flow monitoring of biological tissues.But it is limited by the penetration depth of optical imaging.Blood flow imaging based on this technology is limited to the surface of the tissue.When it is necessary to monitor the blood flow distribution and changes in deep tissues or intracavitary tissues in vivo in real time,the combination of LSCI and laparoscopic imaging technologies is an effective way to solve the LSCI imaging depth.However,in the previous research,it lacks a comprehensive analysis of the influencing factors of the laparoscopic LSCI imaging system.The blood flow measurement is often limited to qualitative measurement.Therefore,this article chooses to carry out research on laparoscopic LSCI quantitative blood flow measurement,and builds a commercial laparoscopic LSCI imaging system.Through a combination of phantom experiment and animal experiment,the blood flow imaging of deep tissues is realized.The research results are as follows:The system analyzes the key parameters that affect the LSCI quantitative measurement,corrects the effects of static scattering and camera noise on the speckle contrast,and determines the correlation of the electric field autocorrelation function through the multi-exposure speckle imaging(MESI)method to achieve quantitative measurement of laparoscopic LSCI blood flow.Aiming at the problem of long sampling time in MESI,the effect of static scattering is corrected by spatial speckle contrast and temporal speckle contrast,and the quantitative measurement of laparoscopic LSCI blood flow is achieved under a single exposure time,which solves the problem of poor quantitative analysis ability in LSCI.It combines the commercial laparoscopy with LSCI to achieve quantitative monitoring of MESI blood flow in the rabbit's ears;it conducts vivo block reperfusion experiments on the large intestine blood vessels in the abdominal cavity of rabbits,based on single exposure LSCI to obtain real-time large intestinal blood flow changes.