Development And Application Of OCT Imaging System Of Skin Blood Flow Based On Swept Frequency Laser Light Source

As the largest organ of the human body,there are various types of skin diseases,and the prevalence rate has increased year by year.The existing methods of diagnosis of skin diseases mostly use histopathological biopsy as the "gold standard",which is invasive and easy to infect.As society gradually enters aging,high-risk elderly diseases such as coronary heart disease and diabetes are prone to cause peripheral arterial disease,leading to severe limb ischemia and affecting the transportation of oxygen and nutrients,which in turn causes secondary abnormalities in skin tissue.Current clinical imaging dermatology technologies include dermoscopy,skin ultrasound imaging technology,skin computer tomography imaging technology,and skin optical coherence tomography imaging technology.The dermoscopy can non-invasively observe the subcutaneous fine structure,but can not obtain the deep structure and rely on the subjective judgment of the doctor;the skin ultrasound imaging technology can obtain the deep subcutaneous structure and tissue,which is not harmful to the human body,but the resolution is low,and the tumor can not be distinguished from the malignant;skin computer tomography imaging technology can achieve high-resolution imaging of subcutaneous tissue,but the imaging effect of uneven parts is not good.Skin optical coherence tomography imaging technology is based on the principle of low-coherence light interference,which can get real-time,non-destructive and dynamic high-resolution images of human skin tissue,and can be combined with optical coherence tomography angiography algorithm to achieve subcutaneous microcirculation imaging without the need for injection of contrast agent,This paper proposes an algorithm for extracting blood flow from biological tissues with uncorrelated standard deviations,and develops an optical coherence tomography system based on a 1310 nm skin blood flow swept laser light source.In this paper,a swept laser light source with a central wavelength of 1310nm is used as the system light source.The swept frequency is 100kHz,which can theoretically improve the detection speed and depth of skin tissue detection;through the design of MATLAB control software,the system can be quickly controlled by scanning and acquisition;the system realizes biological tissue structure and blood flow imaging.This paper conducts verification experiments on the OCT imaging system of skin blood flow scanning frequency source,including glass target experiment,human skin tissue structure imaging experiment,skin tissue 3D reconstruction experiment and subcutaneous blood flow information extraction experiment.Experimental results show that the swept-frequency source OCT system based on the decorrelation standard deviation biological tissue OCT blood flow extraction algorithm developed in this paper can achieve high-resolution imaging of the two-dimensional structure of the glass target and the skin,combined with three-dimensional reconstruction and decorrelation standard deviation blood flow.The extraction algorithm can obtain the three-dimensional reconstruction effect map and en-face of the skin tissue as blood flow images,and has the clinical application potential,which lays the experimental foundation for the early diagnosis of superficial skin lesions and peripheral microcirculation diseases.