Objective: Obstructive sleep apnea (OSA) is a disorder with a high prevalence rate that may induce serious complications. Recent progress in the area of hypoglossal nerve stimulation has played a role as an alternative to conventional therapies though, some patients having retropalatal collapse still have not benefitted. Therefore, here we propose a new type of upper-airway stimulation, referred to as the palatal implant system, which recovers the upper-airway patency by electrically stimulating the soft palate.
Approach: The system consists of two major parts: an implant that stimulates the soft palate through electrodes and an intra-oral device that delivers power and data simultaneously to the implant via an inductive link. Evaluations of the system are conducted in bench-top, in vitro, and in vivo tests to evaluate its feasibility as an OSA treatment, and the potential development of the system is addressed in the discussion section.
Main results: In the bench-top test, the power efficiency was 12.4% at d = 5 mm and the system could operate up to 8 mm distance in a bio-medium. Data transmission was also successful at distances ranging 2 to 8 mm within an error margin of 10%. The measured CSCc and the impedance magnitude of the electrode were 62.25 mC cm-2 and 390 Ω, respectively, proving a feasibility of the electrode as a stimluator interface. The system was applied to a rabbit and contraction of the soft palate muscle was recorded via a C-arm fluoroscopy.
Significance: As a proof of concept, we suggest and demonstrate the palatal implant system as a new therapy for those undergoing treatment for OSA.