报告题目：Design of the Next Generation of Bioresorbable Implants
邀请人：金属材料与表面工程研究所 胡晓君 教授
Jingzhe PAN is professor of Mechanics of Materials in the Department of Engineering, University of Leicester. Prof. Pan is the deputy head of department and head of mechanics of materials research group. The group hosts an EPSRC Doctor Training Centre on metal processing, a joint Material Innovation Centre with TWI Ltd and an Advanced Microscopy Centre. He was awarded the 2018 Verulam Medal from the British Institute of Materials, Minerals and Mining (IoM3) in recognition for his distinguished contributions to ceramics. Professor Pan has published one book and more than 100 papers.
A Holy Grail for clinical cardiology was to develop a scaffold for balloon treated coronary arteries that resorbed once no longer required. Unfortunately, Abbott announced in Sep 2017 that sale of Absorb BVS, the only bioresorbable coronary scaffoldapproved in Europe and US, would end. Despite initial enthusiasm by cardiologists and the devices being implanted in many thousands of patients, clinical evidence of high rates of very late scaffold thrombosis (VLST) led to concerns of the physician community and discontinued use. This is a major setback for patients and a new industry built around BVSs. This talk will presents a review of this setback and a computer modelling strategy to address the problem. A mathematical framework for computer simulation of biodegradation of bioresorbable medical implants, such as the coronary stents, is outlined. The mathematical equations can be solved using the finite element method and used for the design of the bioresobable implants. The material parameters in the equations can be obtained through “reverse engineering” of existing devices for which degradation data exit. The data and equations can then be used to predict the degradation rate of new devices that are made of the same polymer. It has been shown that the mathematical model is able to fit all the available degradation data for PLAs and PGA in the literature. A series of demonstration examples are presented here. In particular the model is extended to predicting drug release from degrading polymeric devices as well as change in mechanical properties, such as Young’s modulus, during degradation. The mathematic model offers a powerful tool for the design of the next generation of bioresorbable implants.