Research On Blood Flow And Oxygen Imaging System Of Lipopolysaccharide-induced Brain Edema Model In Mice

Cerebral blood flow(CBF)and cerebral blood oxygen are important physiological parameters reflecting the metabolism of nervous system.It is significant to detect cerebral blood flow and cerebral blood oxygen.In this paper,optical intrinsic signal imaging(OIS)and laser speckle blood flow imaging(LSI)are combined to build a set of real-time monitoring system for cerebral blood flow and cerebral blood oxygen in brain injury model of small animals.The main work of this paper includes:1.The existing optical imaging technology is analyzed,and the optical intrinsic signal imaging technology is determined as the detection method of oxyhemoglobin.Considering the chromophores in biological tissue,the modified Lambert-Beer law is used as the data analysis model.By analyzing the existing blood flow imaging methods,the blood flow imaging experiment was carried out by using laser speckle contrast imaging technology,and the blood flow image processing and analysis algorithm is proposed.2.Analyze the performance of key components and select the type of components,then finally complete the integration and construction of the system.The optical intrinsic signals imaging system mainly includes halogen lamp,filter and filter wheel,optical tube and CCD camera.The blood flow imaging system consists of 632.8 nm He-Ne laser,beam expander,attenuator and reflector.The two systems are effectively integrated,and the same CCD camera is used to constitute the same field of view imaging.3.Based on the Labview and Matlab,the algorithm of blood flow and blood oxygen imaging and system control are compiled.The software functions include the processing of blood flow image and ROI analysis,as well as the processing of six chromophores and ROI analysis,such as hemoglobin oxyhemoglobin.4.The stability and reliability of the laser speckle blood flow imaging system are verified by the in vitro calibration experiment.The abnormal changes of cerebral blood flow induced by lipopolysaccharide are verified by blood flow imaging experiments.Finally,hypertonic saline and mannitol are used to treat the brain injured mice,and the consistency and difference between the two drugs are evaluated.At the same time,the experimental results also verify the stability of the control software and the accuracy of the data analysis software.The results show that the hardware system can accomplish the simultaneous measurement of cerebral blood flow and cerebral blood oxygen in mice,and the software system can accomplish the effective processing and analysis of experimental data.Meanwhile,the relevent experimental reflects the clinical application value and significance of the lipopolysaccharide brain injury model.