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The goal was to develop a pediatric airway stent for treating tracheobronchomalacia that could be used as an alternative to positive pressure ventilation. The design goals were for the stent to allow mucus flow and to resist migration inside the airways, while also enabling easy insertion and removal. Methods: A helical stent design, together with insertion and removal tools, is presented. A mechanics model of stent compression is derived to assist in selecting stent design parameters (pitch and wire diameter) that provide the desired amount of tracheal support, while introducing the minimal amount of foreign material into the airway. Worst-case airway area reduction with stent support is investigated experimentally using a pressurized tracheal phantom matched to porcine tracheal tissue properties. The stent design is then evaluated in a porcine in vivo experiment. Results: Phantom testing validated the mechanics model of stent compression. In vivo testing demonstrated that the stent was well tolerated by the animal. Since the helical design covers only a small portion of the epithelium, mucus transport through the stented region was minimally impeded. Furthermore, the screw-like stent resisted migration, while also providing for atraumatic removal through the use of an unscrewing motion during removal. Conclusion: The proposed stent design and tools represent a promising approach to prevent airway collapse in children with tracheobronchomalacia. Significance: The proposed technology overcomes the limitations of existing airway stents and may provide an alternative to maintaining children on a ventilator. Index Terms-Tracheobronchomalacia, airway stent. I. INTRODUCTION T RACHEOBRONCHOMALACIA is the most common congenital defect of the central airways [1] and has been identified in up to 15% of infants and 30% of young children undergoing bronchoscopic examination for respiratory distress [2]. The condition arises due to intrinsic weakness of the wall and cartilaginous support. For these children, during dynamic expiration and coughing at low lung volume, pleural pressure exceeds intraluminal pressure resulting in airway collapse [3],

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