“Super-Microsurgical Anastomosis training using the chick embryos within the “Egg-in-Cube” system.”

Abstract

upermicrosurgery techniques are essential skills for lymphatic surgery or perforator-flap surgery. Living animal models, such as rodents, are considered to be ideal microsurgical training models. However, the use of living animal models is costly and involves bioethical considerations.The egg-in-cube, developed by Huang et al., 1 is a novel artificial eggshell with a functionalized surface, which allows high observability and accessibility for embryo manipulation to overcome the drawbacks of the chick chorioallantoic membrane models. We aimed to develop a novel, highly reproducible, and easy-to-handle supermicrosurgical anastomosis training system using the chicken embryo within the egg-in-cube. To our knowledge, this is the first report to show a supermicrosurgical anastomosis training system using a chicken embryo within an artificial eggshell. METHODSThe chicken embryo model within the egg-incube was created in accordance with previous articles. 1,2 The artificial cubic eggshell was fabricated by integrating a polycarbonate frame structure and five polydimethylsiloxane (PDMS) membranes, which have oxygen permeability. 1 In this study, fertilized chick eggs (Sakura; Gotofuranjyo Inc.) were Summary: Although supermicrosurgery techniques are essential skills for lymphatic surgery or perforator-flap surgery, an ideal training model is yet to be introduced. Living animal models, such as rodents, are considered to be ideal microsurgical training models. However, the use of living animal models is costly and involves bioethical considerations. Hence, the authors developed a novel, cost-effective, highly reproducible, and easy-to-handle supermicrosurgical anastomosis training system using the chicken embryo within the egg-in-cube system. Chick embryos were fertilized in the artificial cubic eggshell, which was fabricated by integrating a polycarbonate frame structure and five polydimethylsiloxane membranes. Seven days later, the trainees underwent supermicrosurgical training using the vitelline artery of the chick embryo. The trainees were able to perform supermicrosurgical training using all 11 surviving chicken embryos. The average diameter of the vitelline artery was 0.43 mm. Patency and pulsation were observed after the anastomosis in four of the 11 cases. The supermicrosurgical training system using the chicken embryo within the egg-in-cube system has several advantages. This system is ethically acceptable, less costly and easier to manage than other animal models, and suitable as a supermicrosurgical training model, such as for lymphovenular anastomosis, because the diameter of the vitelline artery was similar to that of the lymphatic vessels in patients with lymphedema. Moreover, the trainee can confirm patency and leakage after the anastomosis because this model has a circulation system. The trainee can practice the supermicrosurgical technique efficiently with simultaneous feedback on anastomosis results.