Imaging For Structure And Optical Properties Of Zebrafish Guided By Mueller Matrix OCT

The exploration of animal models in the field of biomedical research has become increasingly widespread.Currently,zebrafish has become one of the most valued vertebrate models in various research disciplines,due to its scientific advantages such as transparent embryos,easy reproduction,and high homology with human genes.Based on the research of different organs on zebrafish,it can provide a variety of valuable information for various industries.The progress of measurement technology has enriched the research direction of zebrafish’s scientific advantages.Optical coherence tomography（OCT）is a kind of optical non-destructive high-resolution three-dimensional imaging technology,which can not only provide the two-dimensional depth cross-sectional information of the sample,but also obtain the shallow three-dimensional structure of the sample,adding more detailed and complete imaging information for medical image analysis.Polarization-sensitive optical coherence tomography（PS-OCT）is a functional OCT extended from ordinary OCT,which is much sensitive to samples with birefringence properties using polarized light,and can provide further tissue-specific information carried by the polarized light after changing in biological tissues,in addition to the light intensity data that OCT can measure.Based on the transformation of Jones vector and Mueller matrix,the application of Mueller matrix analysis on zebrafish is still relatively rare.In this dissertation,we will use the Mueller matrix OCT built by our laboratory as the main experimental equipment,use zebrafish as the research sample,and perform data acquisition and quantitative analysis based on Mueller matrix for various organs of zebrafish.The specific work content and research results are as follows:1.A Mueller Matrix Optical Coherence Tomography system was used to observe the process of tail fin regeneration in zebrafish,serving as a model organism.Control and comparative groups were set up using clear water and Ecdoin solution,respectively,to observe the development of the tail fin in different solutions.Using Mueller Matrix OCT,a quantitative analysis was performed on the critical time point for growth at each stage of zebrafish tail fin regeneration.The quantification of tail fin thickness and bone tissue both confirmed that Ecdoin promotes tail fin repair and regeneration.Therefore,using the Mueller Matrix OCT system,we have provided a method for measuring the regeneration period of the tail fin.2.A method for automatically quantifying the volume of zebrafish yolk sac as a pathological model.Using Mueller matrix OCT to observe malformation and health yolk sac,approximates them as ellipsoids,and quantitatively analyzes the ellipsoid’s principal axis and volume.Finally,the results are compared with area data approximated by microscopy.The study demonstrates that Mueller matrix OCT provides the advantage of three-dimensional sample information,allowing for a more accurate reflection of sample morphology.3.Zebrafish was used as a developmental model to propose a method for quantifying organ volume changes during development,which was used to measure the growth of various organs in zebrafish.The Mueller matrix OCT was used to observe the developmental changes in zebrafish embryos from 1dpf to 19dpf.The growth of zebrafish body and four organs,including eyes,yolk sac,spine,and swim bladder,was quantified using the Mueller matrix OCT.The results showed that this method not only be used to analyze the volume changes of yolk sac absorbed and growth at critical time points during development but also successfully characterized the volume changes during the development of small organs such as swim bladder and spine.4.The Mueller matrix OCT was used to analyze the structure of zebrafish skin,including the fish scale structure and muscle structure.Based on the different sensitivity of the Mueller matrix elements to the tissue characterization of scales and muscles in the skin,the M₀₀and M₁₁ elements were used to achieve the separation and analysis of the composition of zebrafish skin at the physical property.