Collaborative Research: Computational Modeling, Simulation, and Validation for Tissue Transplantation

重建手术中组织移植的一个基本问题是如何确定可以在不发生坏死的情况下转移的组织瓣的大小。自体组织瓣是从同一患者的一个部位转移到另一个部位同时保持自身血液供应的组织单位。对组织血液供应的解剖结构的更好理解结合仪器和手术技术的进步，已经产生了基于单动脉和静脉转移组织的现代方法。外科医生在决定皮瓣的大小时，仍然依靠个人经验对血供是否充足进行定性评估。如果不成功，血液供应将不足以转移组织的数量，部分皮瓣将无法存活，浪费整个手术。这可能导致严重的术后并发症、额外的手术、发病率增加和医疗费用增加。因此，重要的是要开发一个实用的工具，使最可靠的皮瓣设计的基础上充分的血液供应。为了解决这个问题，该研究项目将开发强大的数学模型，允许估计穿通动脉的直径和给定其大小和形状的组织中的氧合水平。 目前的问题很复杂，需要采取真正针对患者的方法。建模和模拟是必要的，在多个尺度，即，在穿支水平、中间血管网水平和毛细血管水平。使用现有患者数据验证模型是一项挑战。供体部位和受体部位之间的血管尺寸的不匹配产生了额外的问题。基于这些问题，本研究的目标是创建复杂的计算工具，成功的皮瓣转移。为了实现这一目标，具体的研究目标是：1）创建一个数学模型来预测外科皮瓣中的血流和氧供应，2）生成血管结构中的数据驱动模拟和穿支皮瓣中基于图像的验证，以及3）基于（a）血流和氧气输送的模拟结果和（B）来自先前手术的皮瓣参数的数据聚类分析。该研究项目是数学建模，医学科学和外科手术的基础协同作用。所采用的跨学科方法将数学建模社区的专业知识与放射科医生和整形外科医生的专业知识相结合。

A fundamental problem in tissue transplantation in reconstructive surgery is how to determine the size of tissue flap that can be transferred without the development of necrosis. An autologous tissue flap is a unit of tissue that is transferred from one site to another of the same patient while maintaining its own blood supply. Improved understanding of the anatomy of tissue blood supply combined with advances in instrumentation and surgical techniques has resulted in modern methods to transfer tissue based on single arteries and veins. Surgeons still rely on personal experience to make a qualitative assessment of the adequacy of blood supply when deciding the size of the flap. If unsuccessful, the blood supply will be inadequate for the amount of tissue transferred, and portions of the flap will not survive, wasting the whole surgery. This can result in significant postoperative complications, additional surgery, increased morbidity, and increased medical costs. It is therefore important to develop a practical tool to enable the most reliable flap design based on the adequacy of blood supply. In order to address this problem, this research project will develop robust mathematical models that allow estimating the diameter of the perforating artery and the level of oxygenation in a tissue given its size and shape. The problem in hand is complicated and warrants a truly patient-specific approach. Modeling and simulations are necessary in multiple scales, i.e., at the perforator level, at the intermediate vascular network level, and at the capillary level. Validating the model with existing patient data is a challenge. The mismatch of the size of the blood vessel between the donor site and the recipient site creates additional problems. Based on these issues, the objective of this research is to create sophisticated computational tools for successful flap transfer. To achieve this goal, the specific research objectives are 1) to create a mathematical model to predict blood flow and oxygen supply in surgical flaps, 2) to generate data-driven simulation in vascular architecture and image-based validation in perforator flaps, and 3) to design the flap geometry based on (a) simulation results of blood flow and oxygen transport and (b) data clustering analysis of flap parameters from previous surgeries. The research project is a fundamental synergy of mathematical modeling, medical science, and surgery. The adopted interdisciplinary approach combines the expertise of the mathematical modeling community with that of radiologists and plastic surgeons.