The Study Of Blood Vessels Elasticity Based On OCE And Uniaxial Tensile Tests

Great saphenous vein(GSV)is a common alternative to coronary artery bypass grafting,whos elasticity study is beneficial to the development of artificial vessels suitable for coronary artery bypass surgery.The existing researches mainly focus on the mechanical properties of GSV in axial and circumferential direction,lacking the elasticity study in radial direction.While mechanical property of the vessels is anisotropic.Hence it is necessary to study the radial elastic of GSV.Based on optical coherence tomography(OCT)optical coherence elastography(OCE)is noninvasive with high resolution,which is an effective means of GSV radial elastic study.In this study,the elastic modulus of the GSV was measured in three perpendicular directions,axial,circumferential and radial,in combination with OCE and uniaxial tensile test methods.OCE was used to perform the elastic imaging of the GSV,and the image registration algorithm was used to register the imaging results.The displacement field before and after the compression was calculated,and the transition relation between strain and displacement was studied.The final strain field was calculated.Finally,the radial elastic modulus of GSV was calculated.The axial and circumferential elastic moduli of GSV were measured by tensile test.Tension experiments were carried out to obtain the relationship between the tensile force and the length of the vessel,and the curves of stress and strain were established.The uniaxial tensile test results of 69 slits from eight human GSV and the OCE results of same GSVs were analyzed.By comparing the results,the elastic characteristics of GSV in axial,circumferential and radial directions were studied.The range of the elastic modulus of GSV in three directions were calculated.