Abstract: A static pressure was applied in the artery. The displacement and strain distributions of artery wall tissue were estimated using high frequency intravascular ultrasound imaging and two-dimensional motion estimation. The authors obtained "real" elasticity distribution images of different strain vascular tissues for the first time in the world by the reconstructive methods proposed in this paper. When arteries are in the small strain condition, the regions and boundaries of clear elasticity distribution variation are roughly identified. The vascular tissue elasticity distributions are reconstructed by using stress equlibrium equations. When arteries are in the large strain and nonlinear condition, the Newton-Raphson method is used to minimizes the least square error between experimentally estimated and theoretically predicted displacement fields so as to reconstruct elasticity distribution. The vitro experimental results of porcine artery demonstrates that the linear and nonlinear elasticity reconstructive methods are reasonable. The artifacts in the strain imaging can be reduced. Experimental research of vascular mechanics can be advanced to 2D or 3D sub-millimeter microstructure levels. These studies are of great importance in fundamental research of vascular mechanics and in the monitoring and evaluation of PTCA process.

Key words: vascular mechanics, intravascular ultrasound, reconstruction,percutaneous transluminal coronary angioplasty, microscopic elasticity imaging