The Preliminary Research On Laser Speckle Tissue Elasticity Imaging

Tissue viscoelastic coefficient is a significant parameter that reflects the metabolic andphysiological functional state of tissue and organs. Measurement of Tissue viscoelasticcoefficient is of important significance in the study of tissue physiological variation anddisease prevention. Laser speckle contrast imaging is a method using the imaging sensor(CCD or CMOS) to collect the scattered light reflected from the tissue surface, forming atwo-dimensional speckle pattern and using speckle contrast algorithm analysis to get thevelocity fluctuations of the scattering particle. Based on this imaging technique, we proposea new tissue elasticity imaging method--laser speckle tissue elasticity imaging. Comparing toother existing tissue elasticity imaging technique, our method can achieve non-contact, fullfield imaging with high sensitivity and low cost, and the result is not influenced by tissueoptical parameters. The main contents of this paper are as follows:(1) We proposed a tissue elasticity imaging method based on the principle of laserspeckle. Tissue is modulated by external pulse force and then we use laser speckle contrastimaging to measure the propagation of Rayleigh wave which is generated from the tissuesurface. Afterwards the tissue eigenfrequency and damping coefficient are calculatedthrough curve fitting data processing method.(2) We designed a tissue elasticity imaging system. For the needs of tissue elasticityimaging, we selected suitable devices and set suitable parameters for different model withdifferent components.(3) We set tissue phantom experiment to verify the imaging system, and to analyse theinfluence of tissue optical parameters to the experimental results.