Nedrud Stacey, Fleissig Yoram, Sanjuan-Sanjuan Alba, Bunnell Anthony, Fernandes Rui
Department of Oral & Maxillofacial Surgery, Division of Head and Neck Surgery, University of Florida Health Jacksonville, FL, USA.
Faculty of Dental Medicine, Hebrew University of Jerusalem, Jerusalem, Israel.
Craniomaxillofac Trauma Reconstr. 2023 Sep;16(3):195-204. doi: 10.1177/19433875221097252. Epub 2022 May 15.
Microvascular anastomosis has traditionally been executed with a perpendicular transection through the vessel at the widest diameter to increase circumference and thus increase blood flow while decreasing resistance. In Chen's 2015 article, it was suggested that an "open Y" would improve vessel size match, and Wei and Mardini discuss angled transections of the vessels. This project aims to explore the geometric configurations feasible at the anastomotic transection and mathematically model the resulting hypothetical increases in circumference.
The mathematical models were theoretically developed by our team. The formulas model increases in circumference of the transection at different distances in relation to the bifurcation of a blood vessel, as well as changes in circumference at different transection angulations. An in vitro exploration as to the anastomotic feasibility of each geometric cut was completed on ten poultry tissue specimens.
The mathematical models demonstrated the change in vessel circumference, with multiple geometric designs calculated, best shown through diagrams. For example, if the vessel width is 1 mm, the distance from the increasing vessel diameter to the final bifurcation is 1 mm, and the bifurcation angle is 45°, the circumference of the transected vessel increases by 82.8%. Models of transections at different angulations, for instance 30°, 45°, and 60°, yield an increase in elliptical circumference of 8.0%, 22.5%, and 58.1%, respectively. Additional derivations calculate the elliptical circumference at any angle in a single vessel, and at any angle in a bifurcating vessel.
The theoretical and clinical aim of this project is to increase awareness of the anastomotic creativity and mathematically demonstrate the optimal anastomotic geometry, which has not been objectively explored to our knowledge. An in vivo study would further support clinical improvements, with the aim to map postoperative fluid dynamics through the geometric anastomoses.
传统上，微血管吻合是在血管最宽直径处进行垂直横切，以增加周长，从而增加血流量并降低阻力。在陈2015年的文章中，有人提出“开放Y形”会改善血管尺寸匹配，魏和马尔迪尼讨论了血管的斜切。本项目旨在探索吻合横切处可行的几何构型，并对由此产生的周长假设增加进行数学建模。
数学模型由我们团队理论推导得出。这些公式模拟了血管横切处周长相对于血管分叉不同距离的增加情况，以及不同横切角度下周长的变化。对十个家禽组织标本完成了每种几何切口吻合可行性的体外探索。
数学模型展示了血管周长的变化，计算了多种几何设计，通过图表能最好地呈现。例如，如果血管宽度为1毫米，从血管直径增加处到最终分叉的距离为1毫米，分叉角度为45°，横切血管的周长增加82.8%。不同角度（如30°、45°和60°）横切的模型，椭圆周长分别增加8.0%、22.5%和58.1%。额外的推导计算了单个血管中任意角度以及分叉血管中任意角度的椭圆周长。
本项目的理论和临床目标是提高对吻合创造性的认识，并从数学上证明最佳吻合几何构型，据我们所知，尚未对其进行客观探索。体内研究将进一步支持临床改进，目的是通过几何吻合绘制术后流体动力学。
