Hypoglossal Stimulation Device

Obstructive sleep apnea (OSA) is a common medical condition with an increasing prevalence, occurring in 9% to 25% of men and 9% to 15% of women. OSA is defined as upper airway collapse resulting in a decrease (hypopnea) or airflow loss (apnea) for at least 10 seconds. Repeated episodes of hypopnea or apnea can cause hypoxia, hypercapnia, and sleep fragmentation. As a result, patients can suffer from various symptoms, including snoring or gasping for air at night, excessive sleepiness, headache, irritability, difficulty concentrating, and decreased libido.

Traditionally, the diagnosis of OSA relied on in-lab polysomnography. However, home sleep apnea testing is now an acceptable alternative diagnostic tool. The results from either of these tests can determine the severity of OSA using the apnea-hypopnea index (AHI) defined by the American Academy of Sleep Medicine. The severity levels are categorized as follows: Mild OSA (AHI 5-15), Moderate OSA (AHI 15-30), and Severe OSA (AHI >30).

Untreated OSA is associated with numerous adverse health outcomes, including increased motor vehicle accidents, hypertension, type 2 diabetes, strokes, atrial fibrillation, coronary artery disease, heart failure, and increased overall mortality.

The gold standard for treating OSA is continuous positive airway pressure (CPAP) administered via various face or nasal masks. While this treatment improves overall sleep quality and has proven effective in reducing blood pressure and the AHI, compliance is challenging for many patients, with 29% to 83% reporting <4 hours of CPAP use per night. Compliance with treatment is especially challenging over time; noncompliance rates with long-term use range from 11% to 45%.

Hypoglossal nerve stimulation (HGNS) is a surgical option for treating OSA. During this procedure, a stimulator is connected to the hypoglossal nerve, which controls the genioglossus muscle. When the nerve is stimulated, it triggers the contraction of the muscle, effectively preventing the collapse of the upper airway. Studies have shown that HGNS significantly improves the quality of life, AHI, and oxygen desaturation index (ODI).