Development of a microclip for laryngeal microsurgery: Initial animal studies

Abstract

Mucosal closure following laryngeal microsurgery can be challenging due to limited access, and incisions are often left to heal without formal closure. This study explores the hypothesis that a bioabsorbable microclip can be developed as an alternative method to close mucosal incisions in laryngeal microsurgery. Animal study. In vitro studies were performed to determine if a suitable clip could be designed using bioabsorbable materials. A porcine model was used to study behavior of the clip in vivo. We initially studied poly-ϵ-caprolactone but encountered difficulty creating a small clip with the necessary material strength. Using magnesium we were able to produce a clip sufficiently small to close vocal fold incisions. Magnesium is biocompatible, bioabsorbable, and malleable, and has been used to manufacture vascular stents and sutures. The magnesium microclip could be deployed rapidly using modified 2-mm micro-laryngeal cup forceps, which enable the clip to close in a circular shape. In vitro and in vivo tests showed the clip held securely to the vocal fold mucosa. Macroscopic and histologic studies showed no significant injury to the contralateral vocal fold. There was no evidence of lower airway injury after implanting clips into the lower airway. The bioabsorbable clip could be used to close selected incisions in laryngeal microsurgery. Currently we are working to further reduce the size of the clip and modify its bioabsorption properties to enable precise control of degradation.