OCT Based Application Of Non-invasive Blood Glucose Monitoring Biological Tissue Model And Quantitative Evaluation Of Image Enhancement

As a ubiquitous functional disease,diabetes is a long-term hazard to human health,coming with a lot of complications.Tens of thousands of people die from the complications of diabetes every year.In the measurement and prevention of diabetes,invasive and time-consuming methods such as taking blood or taking venous blood are generally adopted.So we need a non-invasive,fast,real-time detection method.Optical Coherence Tomography（OCT）technology is a new imaging technology with high resolution,real-time,non-invasive features.It can achieve tomography in the depth direction of the sample by detecting changes in light intensity from the sample backscattered.By measuring the biological tissue’s scattering information in the depth direction to predict the change of the blood glucose by the change of the scattering coefficient.However,there are many external factors in the measurement process.Therefore,it is necessary to quantify the influence of these factors by designing tissue simulation phantom.The biological tissue simulation phantom is applied to non-invasive blood glucose detection in this paper,and the optical coherence tomography is applied to study the influencing factors in non-invasive blood glucose detection.The model in this paper mainly simulates the dermis layer in the human body because there is a high exchange rate of glucose in this region.Firstly,some materials are choosed as the tissue simulation phantom,Indian ink as the absorber,silk fibroin as the scattering,and polyacrylamide gel as the matrix.Among them,polyacrylamide gel is easy to be prepared and bubbles are not easy to occur.Silk fibroin powder is composed of natural collagen fibers and has more biological characteristics.In the experiment,OCT technology is used to measure optical parameters such as refractive index and light attenuation coefficient of the model under different temperatures and pressures.The experimental results show that the concentration of matrix,scatterer and absorbent in the model is fixed at the wavelengthλ=1310nm.With the increase of glucose concentration,the light attenuation coefficient of the homogeneous skin tissue phantom shows a decreasing trend.In addition,by changing the pressure applied to the surface of the phantom,it was found that as the pressure gradually increased,the light attenuation coefficient in the gel showed a change of 0.0731 mm^-1/N.At the same time,as the temperature increases,the light attenuation coefficient changes by0.0043-0.0048mm^-1/°C.In the data processing,By using the blood glucose calibration algorithm,what we obtained is not only the change of the attenuation coefficient of the whole region,but also the added information of the depth direction in the model,and it verified the theoretical knowledge of the non-invasive blood glucose calibration algorithm.The OCT image enhancement algorithm is studied to reduce the attenuation of the OCT signal in the depth direction and enhance the structural information of the tissue edge by proposing the differentiation of the depth direction of the OCT image.We verified the feasibility of the algorithm through human skin and tissue model experiments,and proposed a quantization algorithm to quantitatively calculate the enhancement effect.Finally,the application of the algorithm was prospected.