Implantation of the nyxoah bilateral hypoglossal nerve stimulator for obstructive sleep apnea

This report describes the surgical implantation of a novel bilateral hypoglossal nerve stimulator (Genio system®, Nyxoah S.A., Belgium) and the successful treatment of a patient with moderate obstructive sleep apnea (OSA).

Surgical technique description and case study report.

The bilateral implantable stimulator (IS) simultaneously stimulates both genioglossus (GG) muscles to reduce airway obstruction. At night, patients wear an activation chip under their chin that wirelessly transmits energy to the implant and enables the nerve stimulation. Surgical implantation of the IS is performed under general anesthesia by making a small incision above the hyoid bone and dissecting through the platysma, mylohyoid, and geniohyoid muscles to the GG muscle. The hypoglossal nerve branches are then identified, followed by suturing the IS in place. The system was evaluated in an otherwise healthy, 60-year-old woman with moderate OSA (apnea hypopnea index (AHI): 25/hr, nadir O₂ saturation: 78%). Appropriate stimulation settings were determined at 2-, 3-, and 6-months post implantation during polysomnography (PSG) and changes in apnea and hypopnea events and oxygen desaturation recorded.

The surgery was well tolerated by the patient with an uneventful recovery. The PSG at 6 months showed that AHI per hour, obstructive apnea events per hour, hypopnea events per hour, and oxygen desaturation index have been reduced by 88%, 92%, 88%, and 97%, respectively, and nadir O₂ saturation improved to 91%.

The absence of complications and considerable reduction of apnea and hypopnea events in this case study help demonstrate the potential safety and efficacy of the bilateral hypoglossal nerve stimulator.

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