EAGER: Topological Optimization Methods for Designing Patient-Specific Large Craniofacial Segmental Bone Replacements

这个早期概念探索性研究（EAGER）项目的目标是应用拓扑优化方法为颅面重建中的大节段性缺陷创建可行的骨替代形式。在因爆炸或肿瘤切除导致的大面积面部损伤并骨丢失后，如何恢复其正常的功能和外观仍然是颅面重建手术中尚未解决的重要问题。目前的方法在本质上是启发式的，骨置换的特别设计是由外科医生在手术时完成的。在给定的由伤口定义的空间内，骨替代物的设计必须满足结构功能，永久保持特定的三维形状，并支持软组织和假体器具。一种多层次的拓扑优化方法将被应用和定制，以创造新的骨替代形式，不仅满足承重要求，而且将组织元素定位在空间的适当位置，以支持软组织和假体器具。将在畸形区域整合替换形式，并验证使用定制颅面设计形状的可行性。该研究项目是组织工程研究、临床外科和计算力学的协同作用。采用跨学科的方法，将中面部的生物力学与拓扑优化技术和有限元方法相结合，建立了一种为颅面重建创建患者特异性拓扑优化骨替代方案的技术。如果成功，这项研究将有可能改善骨缺损患者的生活质量。该项目可以为组织工程设计一种优化的、针对患者的治疗方案提供一种全球方法，在其他解剖缺陷的临床应用中获得最大的治疗效果。阐明颅面骨骼的结构和功能之间的关系将推动组织工程、假肢设计和方法的进步，以鼓励假肢固定和工程材料系统的设计。通过使用工程概念和工具来研究生物和医学问题，将利用多学科方法来研究这些问题，作为培养本科生和研究生批判性思维技能的工具。

The objective of this Early-concept Grant for Exploratory Research (EAGER) project is to apply topological optimization methods to create feasible bone replacement forms for large segmental defects in craniofacial reconstruction. Restoring normal function and appearance after massive facial injuries due to blast or tumor removal with bone loss still remains an important unresolved problem in craniofacial reconstruction surgery. The current methods are heuristic in nature and ad hoc design of bone replacements is done by the operating surgeon at the time of surgery. Within a given space defined by the wound, bone replacements have to be designed to meet structural functions, to maintain permanently a specific three-dimensional shape, and to support soft tissues and prosthetic appliances. A multi-level topological optimized method will be applied and tailored to create new bone replacement forms that not only meet requirements for load-bearing, but also position tissue elements in the proper locations in space to support soft tissues and prosthetic appliances. The integration of the replacement forms in the deformity regions and validation of the feasibility of using the tailored craniofacial design shapes will be carried out.The research project is a synergy of tissue engineering research, clinical surgery and computational mechanics. The adopted interdisciplinary approach combines the biomechanics of the mid-face with topological optimization techniques and finite element methods to build a technique for creating patient-specific topologically optimized bone replacement alternatives for craniofacial reconstruction. If successful, this research has the potential to improve the quality of life for individuals with large bone defects. The project can contribute to a global methodology for designing an optimized, patient-specific treatment protocol for tissue engineering with maximum treatment outcome in clinical applications in other anatomical defects. Elucidating the relationship between the structure and function of the craniofacial skeleton will enable advances in tissue engineering, prosthetics design and approaches to encourage prosthetics fixation, and design of engineered material systems. A multidisciplinary approach to study such problems will be exploited as a tool to develop undergrad and graduate student's critical thinking skills by using engineering concepts and tools to study biological and medical problems.