Prefabrication of a Free Flap for Tracheal Reconstruction: An Experimental Study. Preliminary Report

Abstract

The development of a prefabricated free flap that could have potential for tracheal reconstruction has been investigated in the goat model. Through a staged procedure, a composite cutaneous-chondromucosal premolded, prevascularized flap was obtained by prefabrication techniques. The procedure comprised three surgical stages. In the first stage, on day 0, the cartilaginous frame-work was constructed, along with the vascular pedicle (implantation of an arteriovenous fistula as a vascular carrier). In the second stage, on day 50, the inner surface of the neotrachea was lined with nasal mucosa. In the third stage, on day 60, the flap was elevated and free transferred to reconstruct a 15-cm circumferential defect in the cervical trachea. Ten animals were operated on, and the results were one infection, three early deaths, one free-flap failure with early tracheal stenosis, and five long-term survivors without significant stenosis. The structure of the neotracheal flap closely resembled that of the native trachea: internal respiratory epithelial lining, cartilage rings, and fibrovascular tissue. Fiberoptic bronchoscopy was done to all the animals at 10 and 60 days, revealing no significant stenosis in the long-term survivors.

Prefabricated tracheal prosthesis with partial biodegradable materials: a surgical and tissue engineering evaluation in vivo

“…We have isolated the vascular-bundle prosthesis with a latex sheet to determine the amount of tissue deposition around the prosthesis coming from the vascular pedicle only, without contribution by the surrounding tissue. This is a technique commonly used in reconstructive surgery to realize prefabricated flaps and it could be use either for prosthesis formed by autologous tissue [11] or for composite prosthesis [10], promoting the growth of a layer of neoformed fibrovascular connective tissue through the prosthesis. The presence of fibrous connective tissue is considered the base to elicit ingrowth of a functional respiratory epithelium [15 -17].…”

Flap Prefabrication and Prelamination with Tissue-Engineered Cartilage

“…Prefabrication of a flap has the advantage of generating a free flap independent of anatomic limitations. [22][23][24][25][26] One promising method in flap prefabrication is to implant an arteriovenous axial vessel loop into a random-pattern area. 23,24,27 In 1969, Schechter et al 28 were the first to described revascularization in the thigh regions of adult mongrel dogs using arteriovenous communications or arterial punctures.…”

Tissue Engineered Trachea Using Decellularized Aorta

“…However, this established method is not appropriate for the repair of extensive lesions. Therefore, for these types of lesions other replacement methods, such as autografts [2,3], allografts [4,5], prosthetics materials [6][7][8] and tissue engineering [9][10][11][12] have been studied and developed. Some partial successes have been announced with some of these methods, butso far not one of them has archived a completely satisfactory long-term tracheal replacement for extensive lesions of the trachea.…”

“…With different approaches, both groups were trying to recreate the cylindrical shape of the trachea, combining material and cells to make a more biocompatible tracheal replacement. Our group believes that the requirements for an ideal TET are: (1) easy,less-invasive harvest procedure that yields sufficient cells in a relatively short time, (2) abiocompatible and biodegradable scaffolding that avoids inflammatory responses, (3) proper flexibility and stiffness, (4) air tightness, (5) neovascularization, (6) epithelial regeneration and (7) growth on the insert, which is especially important in the treatment of pediatric patients [15].…”