Development of Endoscopic Arytenoid Adduction Using Cricoid Implant

Abstract

Objectives: We sought to develop a less-invasive alternative to conventional arytenoid adduction using a cricoid implant. Methods: We performed a preliminary study with excised human and canine larynges. A nail-shaped stainless steel rod and an insertion device were designed for an in vivo animal trial. After unilateral recurrent laryngeal denervation surgery in 5 adult mongrel dogs, the implants were inserted endoscopically through a small mucosal incision over the cricoarytenoid joint. Acoustic and aerodynamic data were obtained from each animal before serial euthanasia followed by examination of the excised larynges. Results: The canine cricoid cartilage demonstrated adequate marrow space for implantation. We found that the arytenoid cartilage was successfully medialized and tightly fixed over a sufficient period of time just by inserting an implant in the cricoid cartilage. The animal study showed that the implantation procedure was relatively easy and relatively safe. Acoustic and aerodynamic studies confirmed the functional improvement of the voice. Histopathologic study revealed a favorable tissue response to the implant. Conclusions: Endoscopic arytenoid adduction using a cricoid implant is feasible and could be a noninvasive surgical option for the treatment of unilateral vocal fold paralysis.