Direct hypoglossal nerve stimulation in obstructive sleep apnea

Area of Science:

• Neurology
• Sleep Medicine
• Otolaryngology

Background:

• Obstructive sleep apnea (OSA) is a common disorder characterized by upper airway collapse during sleep.
• Current treatments for OSA have limitations, necessitating novel therapeutic approaches.
• The hypoglossal nerve (HG) plays a crucial role in maintaining upper airway patency through tongue muscle control.

Purpose of the Study:

• To investigate the motor responses elicited by direct electrical stimulation of the hypoglossal nerve (HG).
• To assess the impact of HG nerve stimulation on upper airway patency during sleep in patients with OSA.

Main Methods:

• Electrical stimulation of the main trunk and genioglossus branch of the HG nerve was performed in patients under anesthesia and during wakefulness.
• Polysomnography was used to evaluate changes in airflow during sleep in response to HG nerve stimulation.
• Stimulation was delivered using a half-cuff tripolar electrode.

Main Results:

• Stimulation of the genioglossus branch of the HG nerve resulted in tongue protrusion and contralateral deviation.
• Stimulation of the main HG nerve trunk led to slight ipsilateral deviation and retrusion of the tongue.
• Inspiratory airflow significantly increased (184.5 +/- 61.7 mL/s) during HG nerve stimulation (P = .02).

Conclusions:

• Direct electrical stimulation of the hypoglossal nerve can induce specific tongue movements.
• HG nerve stimulation, applied below the arousal threshold, effectively improves airflow.
• This method presents a potential therapeutic strategy for managing obstructive sleep apnea.