Development of surgical protocol for implantation of tracheal prostheses in sheep

Abstract

Abstract-This article documents experiments performed in ewes to design an artificial larynx. The artificial larynx is composed of a hollow, porous tube that elongates the trachea and is capped with a valve that acts as a laryngeal sphincter. Through an industrial collaboration, our team developed a porous biomaterial that can be colonized by cervical tissues. This biomaterial has been used in animals to replace part of the trachea, but it is meant to eventually substitute for laryngeal cartilage. The tracheal prosthesis is a hollow cylindrical tube composed of titanium microbeads. We performed a study in large animals to establish an optimal surgical protocol for tracheal replacement in humans. The study included 11 sheep (n = 11) and compared 5 methods of implantation. We successfully established an optimal three-step surgical protocol to make the porous-titanium tracheal prosthesis functional: (1) large lumen endoprosthetics, (2) colonization by the peripheral tissues, and (3) endoprosthetic epithelialization. This study is the first step in developing an artificial larynx because it successfully identifies a biomaterial capable of extending the trachea to allow it to open at the junction of the upper aerodigestive tracts.

Laryngeal replacement with an artificial larynx after total laryngectomy: The possibility of restoring larynx functionality in the future

“…3,[13][14][15][16][17] This prosthesis comprises a nonremovable tracheal ring and a removable part. 3,[13][14][15][16][17] This prosthesis comprises a nonremovable tracheal ring and a removable part.…”

“…3,4 The removable part, also made of pure medical-grade titanium, is comprised of a concentric valve system with double openings that allow air to be inhaled and exhaled. A temporary silicone tube is inserted into the tracheal prosthesis' lumen, offering support by calibrating the junction between tracheal prosthesis and proximal trachea, thereby preventing the development of a stenotic granuloma during wound healing.…”

“…The tracheal prosthesis' safe use is derived from experimental studies on animals, such as sheep and New Zealand rabbits. 3,4 The removable part, also made of pure medical-grade titanium, is comprised of a concentric valve system with double openings that allow air to be inhaled and exhaled. This removable part must be implanted via endoscopy.…”

Tissue-Engineered Larynx: Future Applications in Laryngeal Cancer

“…A more rudimentary example of a mechanical larynx has been trialed using a titanium prosthesis with a concentric valve system that opens to allow respiration and closes to avoid aspiration during swallowing. Pre-clinical studies were encouraging in terms of prosthetic integration [71, 72], although in the single human case reported, the patient was still tracheostomy dependent and due to the absence of a glottic sphincter phonation was poor [73]. Long-term follow-up of this case and a clinical trial involving this technology has not yet been published.…”

Multi-Scale Modification of Metallic Implants With Pore Gradients, Polyelectrolytes and Their Indirect Monitoring <em>In vivo</em>

“…All the necessary committee approvals should be taken for animal experimentation according to the governing rules for each country 21 . In our case the Guide for the Care and Use of Laboratory Animals (National Research Council, 2010) is followed and the approval of the University of Strasbourg ethic committee is obtained.…”