Dynamic study on the perfusion process of liver blood vessels with defects under multiple coupling / 医用生物力学

ABSTRACT

Objective Based on the previous researches of hepatic blood vessel perfusion, using dynamic methods to study and simulate the dynamic behavior of fluid and mechanical properties of vascular wall during perfusion of defected liver (blocked or with foreign matter), and investigate the variation patterns and influencing parameters during liver perfusion. Methods On the basis of medical image data, both the liver straight and bend vessel models were constructed. A mathematics method was proposed to estimate the perfusion speed and simulate the flow of intravascular perfusion liquid. Under the condition of fluid-solid coupling, the mechanical properties of vascular wall were analyzed, and the optimization of perfusion parameters under multiple-coupling condition was suggested. Results When the vascular diameter of the liver changed (such as vascular spasm) or in the case of vascular thrombosis, the hydrodynamic behaviors in blood vessel during liver perfusion were as following (1) The deformation in the first half part was much more serious than that in the second half part of blood vessel with different blocked degrees. (2) Under the same perfusion condition, the deformation in bend vessel was much larger than that in straight vessel. Conclusions The simulation results show that the proposed estimation method for perfusion speed is feasible, and the results of liquid-solid coupling analysis on both hydrodynamic behavior of fluid inside blood vessel and mechanical properties of vascular wall during simulated liver perfusion accord with the medical practice. The parameters influence vascular wall differently as follows the blocked degree of blood vessels＞ the shape of blood vessels ＞ the location of foreign matter. The optimal parameter values during liver perfusion are also obtained under the condition of fluid-solid-heat coupling field.