Magnetic airway implants for the treatment of obstructive sleep apnea syndrome

OBJECTIVE: To evaluate repelling magnetic implants to treat obstructive sleep apnea (OSA) using a canine model. STUDY DESIGN AND SETTING: Magnetic forces equivalent to effective CPAP were estimated with benchtop studies. An acute canine model was used to simulate pharyngeal collapse. Tolerance, safety, and stability of the implants were evaluated in a chronic series of 10 dogs observed over 6 months. RESULTS: Equivalence to CPAP (10-12 cm H(2)0) was achieved with low-force (<10 g/cm length), light (approximately 2 gram) implants. Magnetic implants prevented airway collapse in the acute canine. Normal behavior, swallowing, and oral intake were noted in the chronic canine over 6 months. Implant extrusion was 10%. Histology showed fibrous encapsulation without chronic inflammation. CONCLUSIONS: Repelling magnets successfully maintained a patent airway and were well tolerated in the canine. SIGNIFICANCE: Repelling magnets could represent an implantable alternative to CPAP if human studies reveal similar findings.